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MG MGA - All out of ideas - overheating
| I love my old A, more than my B, my BGT and maybe about the same as my midget, but the one thing it does that they never did is run hot. I have: · Re-cored the rad · Flushed the whole system · Changed and checked the thermostat · Put in water wetter · Added an electric fan (yes, I left the original 6 blade in as well and yes the electric is pushing air the correct way) · I have installed the thick felt strip in the correct location · Put in the wide tubing to the heater and to the air-filters · Installed an oil cooler The rub is that it is running hotter this year than last, albeit we are having stupidly hot and humid weather at the moment. I really like to drive it downtown to work each day but I would never make the trip home in the traffic the way it is now running. I’m now thinking I will have to pull the engine, strip it down and hot tank it to insure all the waterways are clear in the water jacket. Did I miss anything? Does anyone have any more ideas I can try before pulling the engine? I know A’s run a little hotter but I live in Canada! How do people set up their A’s in California, New Mexico, Arizona, Australia, etc? Help, please! Roy. |
| R. Maher |
| Get that tape that you wrap around the exhaust from race shops. Best thing you can ever do. You can touch the exhaust when the engine is running, if you don't mind the fibreglass or whatever it's made out of. Stops the carb vaporising the fuel and pushes a good 80% of the heat under the car. It looks terrible, but works a treat and I race mine too. My 0.02c worth. <MARK> |
| Mark Hester |
| Roy: It looks like you've made the usual improvements. What temp do you consider "hot"? Is it overheating/boiling over? What temp thermostat are you running? M.D. '57 coupe |
| M. D. |
| Roy I was listening to and watching our own MGA expert Bob West taking a good look at someone's car when we were all down at Le Mans 2 weeks ago. He raised the following points during his inspection: 1. Just because the radiator is recored does not mean it is okay - A little more information on radiator thickness, pipe diameter etc may help us all give an opinion. 2. What thermostat are you using? He advocates 73 degrees. 3. Most overheating he sees in clients cars (not covered by above) is incorrectly set ignition. It's not sufficient just to set the static timimg. The car should be timed at high RPM. For instance he got me to set my 1800 engine at 32 degrees at 4500 RPM with the vacum disconnected - Runs beautifully cool at 170 all day long (no oil cooler, no water wetter, no electric fan, and the felt strip has fallen off and not made the slightest difference). 4. Even the quality of the coil can have a significant impact. All food for thought. Steve |
| Steve Gyles |
| Steve raises some good points. Timing is crucial. I also fit foam between the bonnet and the radiator when racing and block off the large hole on the distributor side, so the air does not bypass the radiator. If your worried about the thermostat, then get rid of it and fit the blanking sleeve, This will make your heater work slower in winter, but also make the engine take longer to heat up, so don't thrash it when it's cold.... something we should all note. On my hairdressers car (MX5) I had all sorts of trouble with the thermostat, got a new one, still trouble, then I drilled a small hole in the side of it (some thermostats come with this hole anyway) and bobs you uncle no problems again... I'll stick with the exhaust tape one though, that stuff is magic... <MARK> |
| Mark Hester |
| Unfortunately I cannot tell you exactly what temp I am running as the temp gauge is the later C N H. I have only just found a locat place where I can get the correct one. Essentially, the needle used to be quite steady a little below the Normal but it would creep up in traffic on hot days. I would do the usual and turn on the heater until I got an electric fan then I would turn on the heater and the electric fan! It then started to run hotter even when moving in cooler morning weather and now this year it will get well above the N when driving. It has been 33 deg and humid in Toronto this June. I have not given it the opportunity to actually boil over but it does get to the fuel vapour stage. I am using the Moss summer thermostat which is 73 deg. I have just noticed that they now have the sleeved type original thermostat available, do you think that would be worth a try? Again, thank you all for the suggestions, I will for sure take a look at my timing, I think that whole area could do with a major overhaul and as I'm hoping to do the supercharge conversion if I ever get these wrinkles sorted out, it would be a good investment anyway. Roy. |
| R. Maher |
| Oh, I think I might also give the exaust tape a try, this will cool the whole engine bay which has to be a good thing. Thank you for the suggestion. Roy. |
| R. Maher |
Roy, Be careful that your electric fan is not blocking the air getting to the radiator. I usually remove the mechanical fan as these work when you don't need them i.e. when the car is in motion. and fit the electric one behind the radiator, thus not blocking the air flow over the tubes. Some of the clever electric fans can be reversed. Also put a piece of paper over the grille with the fan turned on. If it stays there then you are doing something, if it blows off or drops off it's not doing much. Cheers <MARK> Years of racing !!! |
| Mark Hester |
| I surprised no one mentioned the front grill. Make sure the slates are bent to allow maximum air flow. Check in getting the proper temp guage. Just becuase you put in a new thermostat does not mean it is good. The blanking sleeve will help confirm that. The main thing I would play with is timing as stated above and the fuel mixture to make sure it is not too lean which will also make it run hot. |
| JEFF BECKER |
| Interesting point Mark, I originally intended to do just that but a local MG "specialist" told me not to. They said I should put it in front and leave my other fan on the car. I had previously thought that removing the original fan was a good idea as it wouldsave power... What is the split? How has eveyone else set up their electric fan? Roy. |
| R. Maher |
| Mark My electrical knowledge is fairly basic. But surely, with a DC motor, if you turn the fan around through 180 degress when repostioning from front to rear of a radiator all you need to do is reverse the power leads to make it suck rather than blow. Or am I missing a trick? Steve |
| Steve Gyles |
| Hio Roy. In addition to the oter suggestions, just a few stupid questions: have you verifed that there is enough coolant in the cooling system? Is the coolant a proper 50/50 mix? Is the fan belt reasonably tight? Is your waterpump in known good condition? I once saw an MGB water pump with the impeller vanes rusted away to almost nothing. Are your brakes dragging the least bit? Any of these things could make your engine run hotter than it should. I'm sure you have checked them all, but am being devil's advocate. Cheers! Glenn |
| Glenn |
| Roy; I suggest the following in desending order 1. use a new sleeved thermostat 2. use a fan shroud 3. jet coat or insulate exhaust manifold. Eastwood has a great kit with a special paint which gives the wrap some integraty. 4. If your oil cooler is in front of the radiator, invert it by mounting to the bottom of pannel. Be sure that you have a real problem, that is the engine is hot, not just the gauge indicating so. Get an laboratory themometer to check the radiator. Stay cool, Bill |
| w.g cook |
| Hi again Roy. Another possibility could be that your temperature guage is inaccurate. You might want to run your engine and then verify the coolant temperature by means other than the dashboard coolant temperature guage. These guages usually work fine, but sometimes go out of adjustment and can give false readings. Glenn |
| Glenn |
| Roy, See my other post about changing the face of your gauge to a Jaeger face... Cheaper option... also a guy from Anglo parts offered me one for 50 euro's. Slats are important if your racing, but standard cars should be OK, but that's why they developed the MKII grille.... some people fit these to early cars for this very reason. Not sure how much jet coating would improve things, but it would look nicer than the wrap/ white tape though. Another must, but very hard to fit on MGA's is an expansion tank and recovery radiator cap, so there is no air in the system. But they must be fitted above the top level of the radiator... difficult unless you remove the heater. I'm surprised no one has invented one of these. 0.04c worth now... <MARK> Twin Cam body.... 18v engine... |
| Mark Hester |
| Mark I have an MGB expansion tank fitted below the top level of the radiator, adjacent to the front carb. Works absolutely fine. Why should it be above the level of the radiator? When the water cools in the radiator water will be sucked back out of the expansion tank regardless of its position because the expansion/suction pipe orifice reaches down to the bottom of the tank and will always be below the water level. Steve |
| Steve Gyles |
| Yes I have checked all the basic stuff like coolent level and yes it is 50-50. The fan belt is new and is set correctly and the water pump is 2 years old. I think the grill vanes are okay but will revisit them. One question, would straight water cool better than water anti freeze mix? If so I might use that to see if I can get some meaningful mileage in this year before going crazy in the off season. Unfortunately I'm quite sure I have a problem as I am getting fuel vaporization issues, but I guess it's worth using a thermometer to check. I would love some suggestions as to the best way of fittng an expansion tank, I did have someone send me a photo of how they did it last year but my laptop crashed since then and I lost just about everything... Yep, now I back up! Does anyone recomend a particular rad shroud? Roy. |
| R. Maher |
| Rob, I live in Guelph, just west of Toronto and have not had any overheating issues this year. 1. An electric fan is crap - get rid of it as the fan on the engine works best when the rad is unobstructed. I've run a Hayden electric and it never cooled worth a damn on it's own so I went back to the stock fan. Mind you, I never used them together. 2. I don't have a shroud and others in my club don't either - it's not necessary. 3. The manifold wrap is unnecessary. The heat sheild for the carbs is ABSOLUTELY necessary so make sure it's there. 4. When you say the car overheats, other than the gauge, is there any other indication? 5. If you have fuel boiling, then your carbs are getting too much heat from the exhaust - check that heat shield. The carb float bowls should be cool enough to keep a hand on when the motor is hot - if not, the heat shield isn't doing its job. Paul |
| Paul Tonizzo |
| Roy Re the expansion tank. An MGB expansion tank just fits sideways on between the radiator and the front carb - 5mm gap either side. I fabricated an L-shaped bracket to hold the tank by its MGB strap and attached the bracket to the radiator top retaining bolt (not much space to work in there). The bracket is a bit of trial and error to get the angles just right. The plumbing was simple. I transferred the radiator pressure cap to the expansion tank and fitted a blanking cap to the radiator - I used a dismantled old cap. I connected the radiator overflow to the pressure tank with rubber pressure hose and fitted a rubber pipe to the expansion tank overflow. I have not had to touch the water system in the last year. Not lost a drop. If you wish I can take some photos of my installation. There were alternative installations discussed last year. If my memory serves me right some owners keep the pressure cap on the radiator and place the drain end of the overflow pipe into an unpressurised bottle. I believe the discharged water get sucked back ok as the water cools. Steve |
| Steve Gyles |
| Since the problem is gradually increasing--I would look for something that would either slowly clog or deteriorate over time. That said--I'd check the tune of the engine--get it to rights, as that's about the easiest thing to do. I'd give the engine and radiator a good flush, using a caustic solution. Finally, I'd change the waterpump. I wouldn't do thiese things altogether--just one at a time. Adding cooling capacity, fluid recovery systems and extra fans, just treats the symptoms and not the cause. |
| R. L Carleen |
| Roy, I agree with almost all sugestions made but wonder if exhaust insulation/tape really effects inside engine temp. I'd like to hear more. I also removed my front mounted electric fan. It can be put back on easily enought but I run cooler at speed with out it since, as mentioned, at speed it blocks more air than it blows, especially with its motor in the middle of it. I would anticipate the same effect blocking the back of the radiator. The fan may help siting in traffic but I do think my shroud helps. My shop did an infra-red test and found my gage ran 8 to 10 degrees hot, that was a relief. I run an MGB expansion tank mounted under the heater duct, longer hose but it doesn't block carb air flow. Archives has a recent thread on this subject but you can run, and I recommend, the blanking sleeve, with the thermostat. Much cheaper than the new combined Moss unit, and you can replace or remove one or the other, cheaply, as needed. Appearently the blankng plate blocks a passage that allows some water to recirculate with out passing through the radiator. Others know more about this than I. Good Luck. Steve. |
| Steve Meline |
| I agree with many of the people above and I see a lot of MGAs in the shop with similar symptoms. I agree with MD above: If your car is not boiling over, it is not overheating. It may be running warm and that is fairly normal for MGAs. My customer cars in Michigan normally will run around 190-200. No big deal. The antifreeze mixture is going to raise your boiling point 10-20 degrees, and you get 3 degrees per pound of cap pressure. So you shouldn't boil until you're between 230-250, depending on what you're running. It takes 250+ degrees to damage the engine. I especially agree with Steve and Bob West above about timing. I see a lot of customer cars where the static or idle timing is "in spec" but the total is incorrect. This is due to either worn out advance springs or incorrect/swapped out distributors. I regularly see MGAs with only about 20-22 degrees of total timing at 4000RPM (vac disconnected). That 10 degrees of timing is costing 10+ HP and making the engine run warmer. I also agree with the guys who suggest corroborating your gauge readings. I always use an infrared pyrometer and check the therm. housing and the radiator in several places while the car is idling. It should read about the same as the thermostat. Then I shut the engine off and let it heat soak and the temp should rise 10-20 degrees. Finally, I agree with the guys who wonder about the electric fan. I've removed a lot of electric fans from customer cars, reinstalled the stock fans, and things got better. The front mounted electric fans are the worse, as they do block airflow. Let us know how things work out! --Carl |
| Carl Heideman |
| One other thing to check if indeed you are running hot is the water pump. New ones have a plastic impeller pressed onto the waterpump shaft. When at room temp the impeller assy is one with the shaft, but when hot the impeller spins on the shaft. It would be interesting Roy to see what kind of pump you have.My spare pump from an english company bought many years ago, is of this type.I removed it and put on my original cast iron mowog pump.Maybe Roys impeller is starting to spin more frequently thus making it seem to gradually increase.If you wanted to go thru the work,you could mark the shaft and the impeller,and reinstall. Then you would have to drive it for some time then re check. Hope this might help, Gary |
| gary starr |
| Guy's- I should have said that the impeller when hot can spin on the shaft. Gary |
| gary starr |
| I know this may sound incredibly dumb, but having had it happen to me you might want to check it out. I had a cracked head gasket; not enough to effect proformance, but enough to let exhust gases into the water jacket. A radiator shop usually has a gas sniffer and cant tell you if that is what it is. If so, a new head gasket and an inspection as to what may have caused it to burn through. Good luck. LLG |
| Larry Gray |
| <<<snip>>> One question, would straight water cool better than water anti freeze mix? <<<snip>>> Yes, by about 12%. Use a rust inhibitor if you use water with no antifreeze. Modern antifreezes contain the rust inhibitor. You can also pressure test the system to see if you can use a higher pressure cap. That's better for raising the boiling point than adding antifreeze. Blake |
| Bullwinkle |
| How critical is the water pump RPM in comparison to engine RPM as a function of cooling? The reason I ask is that I may not be running a standard crankshaft to water pump gearing ratio. On my 1800 engine I have a 6.25 inch diameter crankshaft pulley and a 5.25 inch water pump pulley. The water pump therefore spins a bit faster than the engine. The result is I have an engine that sits at 170 degrees all day, but is this in any way due to the high water pump RPM?. I think I am right in saying that the 1500 runs 5.25 inch pulleys on both (perhaps someone could check this out for me), giving identical RPMs. Just more food for thought. Steve |
| Steve Gyles |
| I would add off course that not only is the water being churned around more but also the cooling fan is spinning a bit faster too. Steve |
| Steve Gyles |
| Just done a quick calculation. At 2500 engine RPM my fan/water pump is spinning at 2976 RPM. Steve |
| Steve Gyles |
| Spinning the pump faster will work if you don't rev the engine much. If you rev the engine more as we do to keep up with modern traffic or race, then the water does not spend as much time in the radiator tubes actually cooling. So there is a down side. I use the reverse and spin the pump less. Also try the MGB plastic fan they work much better then the steel fans and are cheep. Exhaust wrap tape if you read up about it is suppose to keep the gasses at the same temperature as it came out of the head, so the gasses do not contract rapidly and flow away from the engine faster. "They" claim fuel savings but the real gain for me is you can work on the engine whilst it's hot without fear of burning yourself. <MARK> |
| Mark Hester |
| I see where you are coming from Mark, but conversely, using your logic, the water spends less time in the cylinder water jacket area getting heated. Steve |
| Steve Gyles |
| There is one thing that no one mentioned and that is the effeciency of the water pump. After all, the cooling system is nothing more than a process where coolant extracts the heat out of the engine and the radiator removes the heat. Therefore the rate of heat transfer becomes critical. The old cast iron MOWOG pumps had a clearance between the impellar and housing body of approx. .004" (.1mm). Replacement pumps with the cast aluminum housing body are all over the place and can be so ineffecient to where cavitation takes place within the pump. There is no reason why a properly set up MGA that is totally stock in all regards cannot run all day in the hottest summer heat and not exceed 195 on the gauge. Been doing it for over 30 years. |
| Don Tremblay |
| Hi Roy all sound advice, I don't think anybody has mentioned mixture, is your car running weak? This is what I have done to improve the cooling on my coupe. 1892cc 'B' block with the 2 rear water jacket holes drilled out (Pete Burgess mod) obviuosly this size of engine needs more cooling than a standard 1500/1600 MGB water pump, 7 blade fan and 6 inch pulley Standard rad with 22mm boss for cooling fan switch in top tank, 90/85 degree C switch fitted Expansion tank ( keeps all the water in the system instead of spitting it out of the overflow) 8" kenlowe fitted directly onto rad core on the righthand side lookig from the front of the car, if you look at the position of the pump mounted fan it doesn't cool about 20% of the radiator 20% antifreexe mix just as an inhibitor Wetter water added Radiator grilles tilted inwards to increase air flow Oil cooler installed underneath duct panel, controlled by a oil thermostat 80 degrees C Inner wings cut out, a la twin cam, to let the hot air out of the engine compartment Felt pad on underside of bonnet 82 degree C thermostat fitted Timing 12 degrees BTDC Richer needles fitted to H6 carbs ( this made a huge difference to the running temperature when the engine was first run this April after initial run) The result? At Le Mans this year it was in the mid 30's (air temp). The engine temp stays at 180 when traveling, 185 at speed on motorways (80/90mph), in traffic queue's, it take a while for the fan to cut in, comes on at 195 and doesn't get any higher, and cools to 180 as soon as you are moving. 600 miles and no water used at all! God, I've tried hard! It's taken 3 year to sort this out! |
| Terry Drinkwater |
| Steve seems Bob West has listened to a bit of advice and now he is spot on. Radiator must be in perfect nick. I have seen "new" radiators that have blocked up after only a year or so. I think that happens when cars are restored and a lot of engine debris comes loose in the first 5K miles or so and thus blocks the new radiatior. Timing is crucial I have always used the high rev method of setting timing, with that technique it can not be wrong. Those plus a correctly set carb/s can not fail to run a car cool. Steve the last time I explained that all to Bob he told me the reason my car ran at perfect temperature was because I use a weber 45dcoe, at the time my friends and I tried not to laugh but we have had some great nights in the pub since. Anyway good ole Bob has it spot on now. The expansion tank is a very good mod and as Steve has rightly pointed out works with it fitted lower than the radiator and the pressure cap utilised on the ex tank. I have this mod and my radiator is always absolutely full of water. |
| Bob (robert) |
| Bob I have to say that it takes a bit of guts spinning the engine up to 4500 RPM in the garage. Interconnecting door to the kitchen. I don't know what's worse, a screaming wife or the feeling that the engine is about to blow apart! I spent £50+ on a good timing light that allows me to dial in the what ever advance I want. One of the best buys I ever made. Steve |
| Steve Gyles |
| Thank you all yet again... There is hope! I will be attending to the timing and mixture forst then working my way throught the other suggestions one at a time. I really do want to get to the real cause of this so I can fix it once and for all. Again, thanks. Roy. |
| R. Maher |
| Roy You don't really think you are going to close this thread down with a few words of thanks. You've got us all going now on one of our favourite topics in the MGA. This one should go on for another 20 posts or until you've fixed the car! Steve |
| Steve Gyles |
| A few comments in a 2004 thread, "Exhaust Wrap" convinced me that exhaust wrap actually increses internal engine/head temp since heat is not disapated through the manifold/header. Also, I run an Aldon 101BR2 points distributer. My shop set the timming, static, per spec. I still fight heat and get what sounds like per ignition knock on grades when the engine is warmed up and sometimes on aceleration. Do I take it the timing may be off? Too advanced? I apologize if these inquireis are a little remedial. Thanks for any feed back. Steve |
| Steve Meline |
| Steve, Static timing is set under the assumption that the spark advance curve is correct for the engine. Thus when your static timing is set on an engine with factory spec distributor, it can be taken that the vacuum advance will be correct at speed. However, as the vehicle ages, the advance springs age, and they may in fact have been replaced with improper springs by somebody else. If your distributor is not factory, you would have to adjust the advance system to insure that you have correct advance when at speed. See Carl Heideman's post above. |
| mike parker |
| Steve, set your timimg with the engine running at 3000rpm to create max advance with the vacuum disconnected. Then set it to max of 32 degree. Your engine will not advance more than than at running speed and it will not matter too much what is reads at idle. Hope to see you this Mon. for the 4 of July run celebrating our "Freedom" from too much taxation and other things from a small foreign country. Come to think of it, we still pay to much in taxes and we don't have as nice of cars as they do.!!!! |
| JEFF BECKER |
| It sounds to me like underhood temps are the problem, Roy. I have been experiencing vaporization probs in the heat and humidity lately, too. Including hard starting from heat soak after a run to the store or something. So I tend to go with the heat shield guys' advice here, maybe including the exhaust wrap. |
| Tom |
| Mike Many thanks for your comments. My distributor is a modern substitute sold to me by Bob West. The settings he gave me covered other RPMs. I plead guilty for over-simplifying my comments in my post! Jeff I presume your comments were addressed to the other Steve. I won't be coming over for your celebrations on Monday. But it's good to see us Brits re-invading by stealth with our little old sports cars!! Have a great day. We usually have a few beers too! Steve |
| Steve Gyles |
| Okay well in defference to Steve I will ask another question, thereby extending this thread! What is the best strobe these days. I know I have one but it seems to have joined several other of my tool's in a great escape! Roy. |
| R. Maher |
| Roy You might want to try an old fashioned way of setting your timing that has worked well for me over the years. Set up your timing either statically or with a timing light. Then take the car out and when it is well warmed up find a long hill and try to get it to ping by accelerating up the hill in high (high load over a range of rpms). If it pings, stop and retard the timing slightly. If it doesn't ping try advancing it a bit until it does ping and then back off until it just quits pinging. This process takes all of the theory and assumption out of the equation and sets the results based on the current physical condition of your engine. FWIW Larry |
| Larry Hallanger |
| Larry has the best idea if you don't now your advance, etc. I used to work in engine dyno, and we would set race engines on the dyno in exactly that way, without the hill. |
| mike parker |
| Roy, If you had the radiator recored locally, it is probably less efficient now. The original radiator core is no longer available or at least very hard to get. Most local shops carry two row and four row core blanks. While a two row fits, it is marginal for cooling. Moss now sells 3-row radiators that are better. I had a local shop put a 4-row in mine. To do this the bottom tank needs to be widened, the top tank shortened (core is taller), and the car's front apron needs to be trimmed. If you have a stock distributor, you typically can't get the full 32 degrees mechanical advance. The dizzy has 12 degrees advance (24 at the crank) and the car kick back against the starter at 8 degrees static. Add a little dizzy wear and it gets worse. While a pertronix will fix a points gap issue, it doesn't fix the low rpm timing scatter and reduced advance. Distributors with the brass double pivots are worse than the later "hatchet" advance limiter. A lot of words but this point is- Run as rich as you can. If you have electronic ignition buy the appropriate performance coil and open the spark plug gaps. This will help with idle quality. I also run non-resistor plugs and spiral "magnacore" style wire. Advance the timing as until it kicks back against the starter then back off till it doesn't. Check for knock at low speed full throttle. Confirm that your radiator does not have a classic 2-row core. If it does, buy the Moss 3 row or have yours converted to 4 row. Adding rows above four doesn't help much. The new ultra-wide tube aluminum radiators are very efficient but you can's solder them to your tanks. If your radiator is built right, take it to a radiator shop and have it cleaned. While they are at it, have them replace the original "deep" filler neck with a new type. This will allow you to run a standard overflow-type cap. I have a cheap plastic tank wedged in front of my heater box. Works the treat. Buy a mid-price multimeter from Sears that will record temperature. They are around 40 bucks and thermocouples are around 20 bucks. This will allow you to verify the temp. Hope this helps, Bill |
| Bill Eastman |
| Bump...as the summer heat is nearing for many of us. |
| Jon Bachelor |
| Sorry if someone already suggested this, but have you tried backflushing the engine? You don't have to pull the engine out, but you'll probably have to pull the radiator. Use a couple short lengths of hose of varying sizes to attach your garden hose to the top water inlet, and run a hose from the water outlet to a bucket. Start up the water and the contaminants should come out. Might help a little and it's easy to do. |
| Rich |
| Pretty much everything already offered, ought to accomplish something significant, or you have an internal problem, perhaps a blockage in the coolant passages. It would not be the first time an owner found a bit of the wire support from sand casting the block left in the coolant passages and clogging things up. This is where a tool such as Carl Heideman uses to spot check engine temp across the block can help pin point a blockage and a hot spot. Also, if you do the back flushing, you might just try doing it to the radiator and the engine each separate from the other. Altho this is one of the best strategies for loosening debris, it can also backfire on you and move crap from the radiator into engine and vice versa. If you go that far and have access to a modest pressure washer (NOT the megaton blast type, but just 2000psi or less), a blast through the passages, especially aimed towards the bottoms, can knock a lot of silty muck out of your engine or radiator. FWIW BTW, Slat angle in a grille today does matter because the aftermarket grilles generally available simply do not duplicate the angle correctly. Take a look at the angle of the slats in a fresh replacement grille compared to factory photos from the 50s-60s, and you will likely see a difference when viewing the new one from the same angle as the factory photos were taken. If you are lucky enough to have a known original grille, then you are lucky indeed and can move on to other possibilities. |
| Bob Muenchausen |
| As one who has just solved his overheating problem, let me jump in. 1- Remove any electrical fan. It blocks 50% of your air flow. 2- Re-core radiator with a 5 pass core. Bottom tank will need to be widened. 3- Bend, don't cut, front apron. You need the rolled edge for strength. 4- Open grill slats for better air flow. My temp. dropped almost 20 degree's. I also use the stock fan. |
| Bob Wrenn |
| I have a 61 MGA and a 69 Lotus Elan+2. Just returned from a family vacation in South Carolina and we drove both cars roundtrip from NY to SC in 95 degree, 90% humidity. Both ran very well, and handled the heat. However, the MGA would begin to run hotter (around 220 deg F) at high speed (70 mph), but didn't overheat (have 7 lb rad cap, 20% antifreeze, water wetter, rad shroud, felt strip, and have extra elec fan which works great in traffic). The Lotus ran consistently at 180 - 190 deg F, except in traffic when it would creep up to 225. One thing to consider...I owned a 61 MGA back in 1969, and back then I remember similar heat issues, before add on electric fans, water wetter, etc. In those days, MG was still in business, dealers worked on the cars and many service stations that handled 'foreign cars' were very familiar with MGs. My car ran well in traffic and on the highway, but, in heavy stop and go traffic, it would run very hot as I remember putting on the heater to deal with the issue. And..back then...highway speeds were 60 mph, not 70, and traffic moved around 60 - 70, not 75 - 90 as it does today. MGA's weren't running at 75 mph sustained highway speeds for hours. Things are different today if you take the car on the interstate and wish to keep up with traffic. steve |
| Steve Nyman |
| I have done the back flush seperately, not much if anything came out. I will have to check my rad tonight to see if it is a two core now, I suspect it is so this may be a contributor. I have just bought a timing light on the weekend so I hope to get time away from "other work around the house" to take a good run at setting it up correctly. I'm not sure what distributor or coil it has but I don't think there is a vacumn advance tube attached. It's been 15 years since I was last tinkering with engine tuning and I think I must have had too much aluminium in my diet because I don;t seem to remember much! I had better hit the books before I start messing about! |
| R. Maher |
This thread was discussed between 28/06/2005 and 12/07/2005
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