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MG TD TF 1500 - Cooling Systems
|Reference my thread about driving in a parade. Thanks for the advice, but now I have another question regarding cooling that arose from some of the responses. |
There really are three issues involved, and they may get technical: heat transfer from the engine block to the coolant, boiling point of the coolant, and the interaction of these two to produce an optimal cooling capability. We all know that the proper antifreeze/water mixture raises the boiling temperature of the coolant solution. My first question is, does this coolant solution transfer the heat better than pure water, or a mixture of water and Water Wetter? (don’t know what this stuff is, anyway) My thought on this one is, if the heat transfers quicker into the coolant and then out through the radiator, then the coolant may not get as hot (heat is a physical entity…think of the cooling system as a conveyer belt carrying sand from one spot to another). Second, while the water/antifreeze mixture has a higher boiling temperature, if it doesn’t transfer heat as well, then the engine could get hotter because the heat isn’t being removed as quickly. Last, is this irrelevant, given that the TD has an unpressurized cooling system?
If this has your head spinning, then you’re probably not the type that likes to ponder where the universe ends! Sorry…I’m an engineer.
|It seems to me that the physical intereactions of coolant is thus.|
Adding Ethylene Glycol to H2O does at twofold job, it increases the boiling point of the liquid and lowers it freezepoint. In heat transfer it is however irrelevant in a closed cooling system which is thermostatically controled to a temp. below 212 deg F.
and in the case of most vehicles about 175 deg F. approx. You can use H2O or a mix. The fluid will not boil away if the heat/cooling transfer rate is in equilibrum between the engine block and radiator. As for "water wetter", it is nothing more than a liquid surficant. Does it lead to better heat transfer rates? Maybe, but not of much significance.
A clean block and radiator/thermostat is all you need.
|Last weekend I was reading the instructions on the back of my unopened bottle of Water Wetter. It states that a less than 50/50 mix of antifreeze provides better heat transfer. I don't believe it specifies what ratio is best. So far I have had no overheating problems here in Florida but the PO claimed the car overheated from time to time. Its time for a coolant change so I am going to go 40/60 and use Water Wetter. I will relate the change, if any since I keep a close eye on the temp.|
|J. M. Haskins|
|I just read back through the archives - someone mentioned that their bottle of Red Line Water Wetter mentioned a 15% addition of antifreeze to the water to act as a lubricant. Plain water transfers heat better than any water/antifreeze mixture. The best heat transfer would occur with a mixture of water wetter and plain water.|
|Plain water is the best coolant and will transfer heat from the engine the best. Mixing anti freeze in the water depresses the freezing point and raises the boiling point, but it makes the resultant coolant less efficient at transfering heat from the engine. The ideal situation would be to use plain water as a coolant. This, however, would lead to rapid corrosion (rusting) of the water passages, which would lead to a less efficient transfer of heat to the coolant (kind of a "Catch 22" situation). In addition to the increased boiling point and depressed freezing point, anti freeze has anti corrosives and water pump lube added to stop rust formation and keep the seal in the water pump from wearing excessively. A person could run with plain water in the cooling system and just add an anti corrosive/water pump lube additive to the system and theoretically have the "best of both worlds", however nothing comes without a trade off. Anything added to plain water is going to reduce it's efficiency as an ideal coolant, so you pays your fee and takes your chances. I have always started with a thoroughly cleaned block and radiator and run with a 50% solution of anti freeze and have never had any problems, even traveling in Southern California in the summer. But, then I am not bothered by seeing the temp gauge creep towards the 100° C mark, since I know that an engine is not overheating as long as it is not boiling while the car is moving (modern cars have temp gauges that do not move into the HOT range until the temp is at 260° F) Cheers - Dave|
|I agree with Dave about the corrosion and lubrication functions of the coolant. It would not take long to cause problems with straight water.|
Don't forget the other factor in the cooling question. Air flow across the radiator is just as critical as the water side relative to cooling.
|Using Watter Wetter and pure water reduced my running temp (on hot days in Georgia and Florida) as much as 15 degrees C. The Water Wetter I use has the anti-corrosion stuff in it. I have also used the stuff without corrosion inhibitor and lubricant, and added Prestone Inhibitor and Water Pump Lubricant with the same results.|
The surfactant effect is to give much better heat transfer between the hot spots in the head and the water and better transfer from the coolant to the metal of the radiator. Using pure water helps the heat transfer thru the liquid because of the much greater heat capacity of water vrs ethylene glycol.
I have been using this in my TF and my B-GT with air conditioning. The GT would boil over in heavy traffic in a few minuites with AC on and 50/50. No more after switching to water and Water-Wetter.
The TF 1500 can do parades with ease. Since switching the temp is never above 85 degrees C under the worst circunstances.
|The use of additives to improve high temperature cooling peformance (modern cars have temp gauges that do not move into the HOT range until the temp is at 260° F)is ONLY relevant when the cooling system is pressurised (and for 260 degrees, a relatively high pressure)For TD's with a non pressurised cooling system you don't get a lot more. Given that the temp guage measures the water after it has left the engine, and that the engine produces the same latent heat under the same load conditions the coolant will be released at the same temperature if the thermostat is working. A 15 degree difference would only be noticeable when using a non thermo system where the system naturally runs in equilibrium due to the lack of a control valve in the system.|
I'm afraid I don't understand what you said. Was it that Water Wetter won't work unless the system is pressurized?
If so, I don't agree because it does work - my car is living proof. I've noticed a minimum of 10 degrees Centigrade on my temperature gauge since adding Water Wetter. Where the car used to run at 85 degrees it now runs at 75. Same radiator, same water pump, same thermostat, same speed, same ambient outdoor temperature. It's not my imagination because I can still make it go up by getting stuck in traffic - just not as quickly and not as high.
If that wasn't what you said, what were you saying?
the idea is not to make the car run as cold as you can (as this leads to unnecessary wear and loss of engine efficiency) but to maintain the engine temperature at the designed level (i.e. at about 85 degrees.) Additives are added to modern engine to further increase the operating temperature over that provided by the increase in pressure generated by the radiator cap.
If you can see a difference between plain water and water with additive using the same thermostat, your thermostat may be U/S as it should remain closed until its correct opening temp is reached, and I believe this should be greater than 75 degrees. In my TD I could actually see the temp guauge change a little as the thermostat opens and closes (Unless driving in ambient temperatures above 90F when the whole lot increases in temp to about 100F and stays there)
|What is the correct operating temp for a TD?|
I was running too hot and recently made some changes to correct the situation. I flushed the radiator and added the MG plastic fan (works great).
Now I run at 75 degrees C instead of 95-100 C. I believe my thermostat is a 75 C model.
Should I switch to 85 C thermostat to maintain a higher operating temp?
Thanks for the explanation.
I'm not sure about that 85 degree C operating temperature though. When mine was running consistently there it didn't take much at all to make it hit 100 degrees C when in heavy traffic down around the beach or in a Cruise-In. With it operating normally at 75 C it is much more tolerant of slow speeds and long stops. Oh, and our weather here is typically in the high 80's, low 90's during the spring, summer, and fall (or so it seems).
|53td with 1800 b powertrain i have a problem with it running very hot almost unbareable are there any solutions thanks|
On your B engine, first a good flush, then fill with water and "Water-Wetter". I bet it will help. Be sure your fan is working effectively.
If not, have your radiator recored with a high efficiency core ( has more and thinner tubes). The racing guys do yhis all the time. Pressurize the radiator ( not easy but can be done)
|It is simple to pressurize the cooling system. Get a filler neck from a radiator shop.Solder a cap on the bottom of the neck, add a pipe to the cap that you just added.Attach a hose from the overflow of the radiator to this. I used a 3/8 drill bracket attached to the bearer plate near the carb overflow pipes. Done. The drill bracket looks like a magnifing glass w/ handle. #7 cap works well.|
|Pressurising a T Type system is not a good idea as the radiator tank is not designed as a pressure tank and will blow up like a balloon when hot then shrink when cold. The long term work hardening of the tank material will lead to fatigue failure (and leakage) longer term. If you want to run a pressure system then a new radiator is a must.|
|I thought there also was an issue about the water pump seals not being designed for a pressurized system.|
true with a T type engine but Warrens query was with a B type engine which always ran a pressurised coooling system.
|Thanks for all the great feedback from around the world. However, getting back to my original concern over what coolant does the best job of transferring heat from the engine, someone gave me another factor to consider. Could there be localized hot spots in the engine that could cause pure water to boil, creating a pocket of steam, which ultimately could cause the pump to cavitate? With the proper water/antifreeze mixture, the higher boiling point might prevent steam from forming. Short of instrumenting the engine with temperature sensors, it probably would be very difficult to determine if such hot spots exist. With this as an unknown, and given that I know my coolant only heats up to 185F after driving in first gear at idle for one mile, would I be better sticking with the antifreeze mixture with its higher boiling temperature?|
|Chaps, This month's "Safety Fast" has an article about cooling. It describes the use of electric water and booster pumps (with electronic controller) and electric fans. The electric pumps are of course independent of engine speed, so would ensure that water circulates well even at idle speed. The main pump capable of pumping 90 litres per minute, and can be made variable from 90 - 20 lpm using the smart controller. Booster runs at 13 lpm. These can be used on older MGs, apparently, running in conjunction with the existing water pump.. Manufacturer is Davies, Craig Pty Ltd of Oz, distributed in the UK by MAW solutions. Hope this helps, AB|
|Steve, the local hot spots do not cause cavitation, cavitation is caused by the lack of a restriction, i.e. a missing thermostat. The local hot spots, or steam pockets are prevented by a pressurized cooling system & antifreeze.The engines should be run hotter, not cooler to be more efficent. I understand the concerns of the radiator under pressure, & vapor lock, but a 4# cap, & temp. under 220 F.w/ anti freeze,. along with isolating the carbs. & floats, is better than a colder engine, w/ no antifreeze, & no pressure cap. All cars have been doing this since the TD, for thermal effiency & to prevent head gaskets blowing out, & cracked heads, along with preignition/ detonation from the hot spots.[These steam pockets can form well before boiling in the entire cooling system at well below 212 F.|
If memory serves (and it is not all that great) I believe the original owners manual says 80 to 90 degrees C is the normal operating temperature range. I was really happy since mine stays around 85 except in slow traffic on a very hot day. Now I can start to worry about steam pockets. Thanks Len!
|J. M. Haskins|
|It is intended that steam bubbles form in the coolant at high heat areas (over the exhaust valves, remember it is 1800 degrees just a 1/4 inch of iron away)). This is the most efficient way to transfer heat to the coolant because of the extremely high heat of vaporization of water. the bubbles then radiate their heat to the surrounding liquid and condense. This happens long before the bulk coolant is at boiling. However the steam bubbles themselves are a poor conductor of heat, so if the bubbles stick to the surface and get too big and create a thick layer then heat transfer from the head to the coolant suffers. "Water Wetter" changes the surface tension of the coolant and makes the steam bubbles break loose sooner (and much smaller), resulting in a faster heat transfer to the liquid.|
Remember our T-cars were designed when you used water as coolant except in winter when you added anti-freeze (methyl alcohol)
Folks, "Water Wetter" works great! For those having heating problems.. Try IT!
|Don, (and/or ?),|
I have been running a 60/40 mix of H2O & Antifreeze with Water Wetter added to the mix in my TF1500. Recently another owner pointed out that Water Wetter should be added only to pure water. Any feelings / advise on adding "wetter" to an H2O/Antifreeze mix?
Not having any overheating problems.
David 55 TF1500 #7427
|See Red Lines web site for the details but it says you can use it with Glycol based Anti-Freeze.|
|As Peter says, You can (and should) use it with glycol mixtures. It will run cooler. It's just that you get the most effect with plain water. The other owners comment that it should be used "only with pure water" is incorrect.|
If your car is running cool enough for your driving, you have the correct mixture!
Everyone who is interested should view the RedLine site given above.
|Our 1954 TF has a clean block, radiator and hoses. This car sat in storage for 20 years with the same coolant in it. When I originally drained and flushed the system it was very clean. I refilled with 50/50% solution of distilled H2O and orange Prestone anti freeze plus a small amount to water pump lube.|
Never have I had a problem with overheating even driving in 95 deg weather at 4500 rpm.
What's with this water wetter stuff. If you have a closed cooling system how can it reduce the the coolant temp by 10 deg. Correct me if I'm wrong, but the thermostat controls the operating temperature not the coolant. It "may" improve heat transfer rates but thats about all.
"overheating even driving in 95 deg weather at 4500 rpm" @ 4500 rpm you have to be going 60/75 MPH regardless of what rear end you have! If you check the first posting...this all got started regarding "driving in a parade"...quite a different enviroment than blasting down the roadway at full speed! Also Steve's question was more aimed at the TD that does does not have a pressurized system like the TF does. I will aggree that "clean block and radiator/thermostat" is, with out a doubt, the best place to start!....but sputtering along a mile or so of stop & go traffic for an hour or more could be a bit taxing on the old cooling system of just about any auto...(worse if he has the air-cond up full!)
Safety Fast...not Safety Slow!
David 55 TF1500 #7427
|The purpose of the thermostat is to get the engine "warmed up" as quickly as possible to some minimum operating temperature. Then the heat transfer rates from head to coolant to radiator to air determine the temperature. but always kept above the minimum by the thermostat (as on a cold day). Unlike our modern systems the T- Series engines were not designed to work in "Tropical" climates ( ie. anyplace warmer than the UK or above 80 degrees F). With age and corrosion our 40+ year old systems are somewhat reduced in efficiency. |
The standard was a 160 deg F (71 deg C) thermostat or a 180 F (82 C). If your engine runs about 80-85 on a good hot day (95 F) you are OK. If not a clean, flushed system and "Water Wetter" with or without glycol may be the answer.
It improves the rate of heat transfer from the metal to the coolant and from the coolant to the metal of the radiator.
|I really got a great string of comments going on this one, and didn't get trashed too badly! I checked the Water Wetter web site as Peter Moore suggested a few comments back. It has great info on the dynamics of a cooling system. Perhaps a little too technical for most, but a great amount of info to help make decisions for specialized applications, which is what I was looking for in my original note a few weeks ago. Did this one set a record for the number of replies?|
|Okay, you guys win. I just drained eight quarts of 50/50 mix out of my radiator and replaced it with distilled water to which I added 2 ounces of Redline Water Wetter. That's some expensive stuff, US$10.99 for a 12 ounce bottle. This should give me just about an 80/20 mix of water to glycol. |
I'll let you know what happens in the Fourth of July parade. But I'm going to miss that water temperature reading on the oil pressure scale.
|Still planning on driving in the 4th of July parade (assuming it doesn't rain that day) and will leave my coolant as is. Will let everyone know afterward how well it worked.|
|Eight PINTS, not quarts. Ah, these senior moments.|
Been sooooo long ago (long thread)....don't forget the
"snap cold" packs & bundgie cords for carb cool down!
This really does work! Don't put em on....but if you have them with you and have a vapor-lock problem you will look really cool if you open the bonnet and get the car running again in seconds flat! If you don't need/use them...they are great for a quick hot summer day cool down on back of the neck!
Cheers & Best regards...see you in Dayton @ Brits show?.....I'm comming armed with a "soaker squirt gunn" ...gonna get that "T" wet ....if I think I can outrun ya! :-) !!!!
Sir David of "wet-T"
|In our region we have actualy, from 4 weeks, a temperature outside around 35 degree C each day. I was a little bit afraid to run my TD in such a climate. We are in a region of mountains, autoroutes etc.|
I was surprised to see that the TD was excellent in this situation, the max temperature I reached was 85 degree C. Lastyear it was not the case. After I have nanalysed the situation, I was happy to see that the work I have done , last winter, was the right one.
First I have modified the water cooling in changing the radiator with a modern grill, more efficient, I fit again a thermostat(74 degree C),I have suppressed the by pass sytem in the cooling, and I have fit a oil cooler under the apron. That works!!
|To all who have contributed to this Cooling thread,|
Most of us in the East are experiencing high temps this week. I just checked my bedroom thermometer which is in the shade and it indicates 36 which I think is some where between 95 and 100 degrees in the old system.
So I thought today would be a good day to put my new electric fan to the extreme test, as I too have entered my TF along with 9 others in the MMGCC, in our Canada Day (July 1st) parade in Montral. I was able to climb Smugglers Notch at GOF 74 and the fan came on and did its job, but the ambient temp that day was a lot cooler than today. So I'm off for a little "toodle" admidst the 250-yr-old arched maples and covered bridges of Rockburn.
Most of those in our club installed 12" fans in their TDs, but the TF rad is a little more restrictive and I had to settle for a 10" (Pep Boys - $70). ... looks OK so far.
I am grateful to all of you for your contributions, especially from Don Hammer. I am an electrical engineer and don't know diddly-squat about heat transfer, etc. I have indeed, learned a lot.
But I'm still uncertain if I can benefit with the addition Water Wetter to my present 50/50 mix of Dupont Dex-Cool Prestone, or if there's any chemical incompatability.
In any event, if I don't return from the regular Wednesday British Car evening at the local Irish Pub, conside one of two things a) the TF over-heated or b) ... you figure! In either case, my results may be a little late in coming. In the meantime ...
Grateful for the good advice. Stand By.
Gord Clark #100
|Gordon A. Clark|
Please tell us more about the fan. Is this something that I can add temporarily when I think the situation warrants, then remove the rest of the time?
|OK. After last years heating debacle I tore out my radiator and took it down to the shop for a look see. The core was in generally good shape and it had three sets of tubes but there was some solder in a number of the ports and the radiator guy sold me on a new core that had 1/3 more tubes. Supposed to be more efficient.|
I checked with him on the Redline and he stated 50/50 with Redline and to use distilled H2O.
Its 104 here today and I am sure we will have a number more of these hot days so in about a month when I get everything back together and painted I will be able to give it a try.
|Due to the extreme temps we get in the St Louis, MO area in summertime, I installed a seven bladed plastic fan from an MGB. The hole pattern is the same as on my TD but the bolts are smaller in diameter than those used on a B. A simple aluminum bushing cut to length fills the holes in the fan hub and fits very nicely. The banana yellow color was a bit too much so I painted it with flexible bumper primer and flex gloss black paint. Hardly anyone notices that it is not the original.|
There is not much difference in the engine temperature at speed but in slow traffic, it really helps pull the air through the radiator. I can normally see a reduction of about 5 C in traffic or at slow speeds.
|It will be interesting to see where this thread goes after the 4th of July! Looks as though quite a few will be "parading" then. Looking forward to the reply's to see what worked/didn't work for everybody!|
Cheers to all have a great holiday....I have to work...so no "fun" for me.
David 55 TF1500 #7427
|I too installed the "yellow plastic" seven bladed MGB fan. |
What a difference!!! I tried the water wetter route and got modest success, but The fan keeps me at least 10c degrees cooler. So much so, I now know I have a 75c themostat. Before I would shoot right past 75c straight to 100c while slowed in traffic on a hot day.
I didn't paint it however, I like to see the little yellow thing moving and keeping me cool.
|RESULTS OF RAD-MOUNTED ELECTRIC FAN|
Well, our Canada Day Parade (July 1st in Canada ) is over and I learned a lot. I had previously entered my TF into a little local parade and all seemed to work well.
However the July 1st parade was indeed an acid test.
My newly-installed 10" puller fan worked when it was supposed to, but I wouldn't do it again the same way. (There is more room in a TD for a 12" fan - same price)
My first mistake was mounting the temp. sensor (thermo-switch) high into the header tank because it was recommended that I do so (and against my wanting to mount in the bottom header). This meant that unless the sensor was fully covered with liquid (which was NEVER), it would only measure the temp. of the vapour in the header. The result of this was that in order to engage the thermo switch, the vapour would have to be at 96ºC, which in turn, meant that the liquid itself was at least at that temp. In turn, this tended to boil-off a very small amount of liquid.
In a better situation, a thermo switch should be mounted directly in the liquid, or to use one of the sensors that fixes directly to the outside of the core.
The second mistake was the selection of the temp. range of the thermo-switch. This is an ELTH switch from Luxembourg, and I took what was offered by the Volkswagen dealer - on at 96º, off at 68º. I went to the ELTH web-site and it appears that they are bankrupt, so getting a sensor with lower settings, may be a problem..
My biggest mistake however, was in trying to get too fancy by trying to ‘automate' the system, with a rad-mounted sensor, etc. Most of the others in the parade (including a J2) had simply hard-wired a manual switch which they engaged as needed, or left it on all the time - no sensor!. My next move is to wire-in an "Man-Off Auto" switch under the dash, and that should put the issue to bed!
However, I must say that I am almost satisfied, as the engine did not overheat even at ambient air temps. of 30ºC+, and most of the time, the gauge cycled between 85º and 96º.
|Gordon A. Clark|
|Since this thread started about parades, I wound up in a 4th parade at the last minute.|
I use "Water Wetter" and pure water in my TF1500.
The air temperature was 86 F and humidity 96%. The parade route was about 2 1/2 miles and we move at about 1.5 - 2 MPH with lots of standing for no apparent reason.
The engine temp started out with the needle on the low side of the 85 degree C mark and at the extreme high ( just at the end of the parade) was just above the high side of the mark.
The TF is a pressurized system at 4 lbs/sq.in. but in the olden days, I would have been steaming by the end of the parade (110 deg. C or more) with only 50/50 mixture.
Folks, the "Water Wetter" works as advertised. I use it in my T and my MGB-GT (with air conditioning) no overheating even in stop and go traffic.
|I have a 53 TD that I am just getting on the road. The few short trips I have made, 15-20 minutes, have produced 90 degree plus readings. I am waiting for Antique plates and cant take a long ride yet. What is normal operating temp?|
|Since I'm the one that started this thread a few months ago, I'm happy to report that the TD ran great in the parade. Outside temp was about 75 deg F, and the parade route was straight into a light breeze. I shut the engine off while we waited to enter the parade, then drove in first gear the entire way. I shifted between first and nuetral a lot, and had to ride the clutch a few times, but not as much as I feared. Temp gradually made it up to 175 (normal for my car is about 160) by the end of the parade (about 1 1/2 miles). A longer route might have been a problem...may never know. Despite all the great advice I received, I wound up doing nothing special to keep the engine from overheating. Only problem was that the antique cars followed too closely behind the Budweiser beer wagon pulled by Clydsdale horses...fortunately TDs maneuver quickly!|
Thanks to all my MG friends from all over the world for all the advice and info! Sounds like we've all had unique problems and experiences with our cars.
Glad to hear all went well for you!
"Clydsdale horse poo"...yikes...you would have had to drive her in the rain to get rid of that!
Just "yankin' ya a bit" here...all in fun!
Still hope to see ya in Dayton if I can make it!
Cheers, (first of them "on me")
David 55 TF1500 #7427
|... just when we thought it was dead!|
It seems that cooling is a seasonal topic, interspersed with parade projects and those who just can't seem to keep a cool head!
I am glad we have all reported on the various successes (mostly) of various modifications, and just as this thread was about to sink to the bottom, up pops something new!
For those of you fortunate enough to receive Safety Fast, the organ of the MGCC, you will undoubtedly have noticed an article in June's issue on pages 12 & 13 entitled "Keep it Cool".
This article sheds light on an interesting pair of new products that will be of interest to those with vintage cars like F/D/PA/PB/J2 MGs, etc. in which cooling of the medium is by convection. While this may work just diddly-sqaut in the coolish highlands of Scotland, it don't cut the mustard on the sunny flats of New Mexico, or for tha matter, in a parade.
An Australian company Davis, Craig Pty. Ltd are manufacturing small 12V DC circulating pumps for automotive applications.. For years, I tried to locate just this pump in the process control circles, but always came up empty-handed. The pump is available in 2 sizes - a variable speed pump of 20 to 90 litres/min and a much smaller one at 13 litres/min . They also manufacture a controller that uses coolant temperature to activate the pump.
These pumps are made of glass-impregnated Nylon (hmmmm ....). Good technical data and pricing can be found at their web-site :-
If anyone wants a copy of the article, please let me know and I'll scan it and e-mail it.
|Gordon A. Clark|
|Here are my thoughts on adding an auxiliary water pump. |
First, lets assume that MGs operated at the correct temperature when they were new, and could tolerate a situation such as driving in a parade or idling for an extended time (remember…I said lets assume!). That means they had adequate flow for the coolant to remove the heat from the engine, and adequate heat exchange in the radiator to remove the heat from the coolant.
Now, if a car starts overheating, something in the above process isn’t working properly. For the sake of argument, lets assume the thermostat is operating properly. Now, here are several possibilities:
1. Poor heat exchange from the coolant to the radiator, caused by scale or crud buildup that slows the heat exchange between liquid and metal, or by buildups that blocks off portions of the radiator. In the former, the scale actually can act as an insulator, slowing the heat transfer.
2. Poor heat exchange from the engine into the coolant. This also could be caused by the buildup of scale or other crud in the engine, as in #1 above.
3. Poor coolant flow rate. In this case, heat exchange is taking place, but hot coolant just isn’t getting to the radiator at a fast enough rate to prevent a temperature buildup.
Certainly there are various fixes we can attempt. Since most of us lack the sophisticated diagnostic tools found in many shops, lets start with the simplest and least expensive steps first. If it works, then we fixed the problem. If not, then go on to the next step. The first “fix” might be a cooling system flush. This will clean out crud and scale, and hopefully improve the radiator’s cooling capability. Of course there are risks…this crud probably keeps many old radiators from leaking! Also, check the exterior for a layer of rust. The rust particles trap air, and also makes another insulator. The next step might be a bigger fan or an auxiliary electric fan (the 5-blade MGB fan might be the next thing I try…fairly simple to install and easily removed for a concours show). I would reserve the auxiliary water pump for last. It’s probably more expensive, cannot be easily removed if desired, and, most important, if the engine or radiator are filled with crud, probably won’t make much difference.
As I said, my $.02 worth.
|The adventure continues.........OK, my 53 TD has always seemed to run hot, I have seen the temp gauge needle indicate the oil pressure "100" on several occasions. My fix was the following four things, 1) opened ( read bent ) the grill slats for optimum air flow, 2)added water wetter, 3) blocked off the small hose going to the thermistat housing except for a 1/8 inch hole in the baffle and 4)added the MGB yellow fan. All is well now, on the hottest days she runs between 85 and 93. Hope this helps someone. Now if I can get the second click on the doors. Tom|
|I am still convinced there is something in the US with the unleaded fuels we have been burning. Up until about 15 years ago I could run in 100+ F temps without getting overly hot. Now it seems to run about 100 whenever the temp gets that hot too.|
Just got through painting my radiator and will install over the next week or so after I repaint the grill slats (that ought to cool it :-). Then I can test out my new core. We have been running 100-106 F temps for the last few weeks and I am sure we have just begun. A real hot summer. Add to this our mountain roads and you have a great test bed. I am also going to try regular gas just to see if there is any difference as I have always run premium.
<I am still convinced there is something in the US with the unleaded fuels we have been burning.>....
Curious...have your heads/valves been modified for "unleaded"? Do you use a lead additive (do they even sell that in "Clean Green Cally"?) When I purchased my TF there were several empty bottles of lead additive in the car....so I do continue to use this. (subject of much debate on this BBS in the past!)
I do live very near a drag strip that sells "leaded hi test"....but have never tried this in the XPEG. Anybody ever try using such a fuel in their LBC?
David 55 TF1500 #7427
|What an interesting tread. Cooling.|
On my 1951 TD I fit an electric kenlowe fan which it seems for me just enough for normal outside temperature. Since 7 weeks we have a daily temperature, outside normal average, around 35 degrees C each day, the TD runs perfectaly well except when I climb the mountains around, it seems that the fan is too small. I am interested to see how we can fit on the td an MGB fan, do we have enough space between the radiator and the water pump? On my TD the mechanical fan is away.
Your comment: " am still convinced there is something in the US with the unleaded fuels we have been burning....." is on the mark. The additives for "oxygenation" make it burn hotter. I don't think they nuse the same stuff in Europe or GB. This does add to our heating problems. Ask any VW Bug owner, most have burnt a hole in piston #3 if they run at expressway speeds for several hours. My son burnt up three engines, 2 in the camper, 1 in the Thing. The engine rebuilder confirmed that the new mix fuels were giving him lots of business.
|Dave and Don: Yes I have experienced the heating with both the new and old valves. Also have tried the lead additives. Only thing I have not tried is regular gas.|
Anyway may be moot with new raditor but we will see.
|The MGB fan fits well with no modifications to it. You will have to make some bushings to adapt the MGTD/TF fan mounting bolts. The original bolts are smaller than the holes on the MGB fan.|
Be sure you get a MGB fan with the metal inserts still in place.
This is a very good solution. If you take the time to paint the yellow fan with a flexible primer and black paint it is hardly noticeable.
|The new radiator core has really put me in a new spectrum. In 100+ F temps in mountain driving it never got above 85C on long grades and ran at 80C on flats with 70C on downhills.|
I’ve waited for the last two months to post on this thread. I have a 52 TD that does not over heat even when driving in the mountains in July and August. The outside temperature here in Virginia is usually in the 90’s. My car does not have a thermostat in the radiator system. I run a 50/ 50 water and anti-freeze mixture. The by pass was pinched off and welded shut. The radiator was re-cored during the rebuild. I think that each car is different. Some have been totally rebuilt with the engines hot tanked and radiators re-cored. I also think if you are into a rebuild of a T engine that you should make sure that it is hot tanked and the two holes drilled, as mentioned in Horst Schach “The Complete M.G.TD Restoration Manual “. I also change the coolant every two years, just to make sure it stays clean. For those of you who don’t have a rebuilt engine you probably have a build up of scale and rust in the engine and radiator system. If you have a rust color in your coolant this is most likely the reason for your overheating problems. Rust forms a insulator on the engine block and dose not allow proper heat transfer to the coolant Bigger fans and water wetter will not correct this. Also if you are into a ground up restoration, you should store your radiator, filled with coolant and not dry. Any scale and build up in a dry radiator will flake and plug up your passages. I learned this the hard way on my rebuild. Oh yea the reason I waited two months to answer this thread I was out driving the TD in the beautiful Blue Ridge Mountains of Virginia.
Hope this helps
Yes Chris, you can see the water move.
|John C. Hambleton III|
|I completely concur with the rebuild officianados. I run a Shorrock supercharged 1250 TD which was totally rebuilt 14 years ago. The engine was tanked and rebored to 80 over and the head planed to about 8.5:1. The radiator was recored with the original number of tubes and no alterations were made to the plumbing or other parts.|
The car, if anything, seems to run a little on the cool side, assuming the gauge is correct. Here in the Pennsylvanian hills (but not mountains, like some) and on 90-95 ambient degree days, the temp will rise to about 90 on long hard climbs. One I particularly have in mind is an ascent of about 1500 feet over a two mile fairly straight stretch of road where the trotter can be held down for an exhilerating experience. Topping out at the usual 65+ mph, the temp gauge will show about 90F. On the descent the other side, the needle falls rapidly, and if I allow the car to coast, (a most unusual occurance), the temp will fall to around the 65 degree mark by the time I reach the bottom.
Cruising on the Interstate at app. 3200 rpm with a 4.3:1 ratio rear axle,(app.72 mph) I seem to keep at about 85F.
For winter motoring I use a radiator muff which blanks off some or all of the airflow according to the OAT and this seems to keep a decent working temperature, again around 85F
I am certain the problems with overheating are mostly caused by blocks, heads and radiators which aren't clean. I also think that it isn't a great deal of help just to attend to one of those problems. The whole lot, properly corrected, will produce the best and longest lasting results. But of course, there are other causes, such as retarded ignition and weak mixtures to which due consideration must be given.
This thread was discussed between 16/05/2003 and 29/07/2003
MG TD TF 1500 index
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