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MG TD TF 1500 - My TD is sick these days
|On my short trip to Sweden last weekend, my car stopped 6 times. I had full service on it just three weeks ago, but now we have problems finding what is wrong. When I tried to drive it yesterday, it was misfiring so much that people around may have thought some terrorists had arrived. I took it on a truck to a garage (with specialists). They worked on it for a couple of hours, searching through the fuel and ignition system. In the end they made it work in a way, no gun shots this time. But just a kilometer mon my way home it started to misfire again. I just made it to the other specialist around Oslo. They changed the plugs to the right kind, the first garage had put it new, but short ones. Of course the gas pump had been changed, but we changed it once more. The condensator and distributor had already been changed once. The coil had been checked. The carburettors were checked and adjusted.|
Still no good. I had to leave the car there over the weekend. I don't know much about engines myself, unfortunately, but have always been told the these MG were easy to repair.
The only thing we could think of now, were the plug wires and water in the gas.
Any suggestions and ideas?
The TD is my only car these days. I therefore have no car for the Norwegian winters, but I had hoped for nice trips in summer. Last year I went all the way from Oslo to Lofoten Islands, north of the Polar Circle with no problems at all!
|I'd change the condenser (again) and the rotor.|
|raymond, to me it reads as if very little troubleshooting was done...it sounds more like remove and replace..because if they were troubleshooting and testing i really doubt ALL of those components would have failed simultaneously...you say the garage was specialist..i do not see from what you write here how they qualify for that title. specialists analyze, test and from those test results FIX problems..which may involve replacing a defective component. |
none of this is written as a rip on you. to me it reads like you were ripped off. there are mediocre shops out there.
when you say "the coil had been checked" what method and under what conditions was it checked? i have had a coil breakdown with heat. car runs fine when cold and misfires when the coil gets warm.
how was your car running before you "...had full service on it three weeks ago" ? what did they do during that service? what test was run to determine the distributor and condensed needed changing? did they test the ignition leads?
best of luck...you are correct these engines are very basic and very easy to work on. if you have fuel of the proper ratio, good spark at the proper time and compression these engines run like top. best of luck. let us know what you learn. regards, tom
|I am sorry that my first post seems to have come out in a wrong way. t lange, they did change the condenser twice and they did change the rotor.|
Tom: a lot of troubleshooting was done! That garage has been working with old sportscars for 30 years and are trusted by the sports car community. Most of the Morgans and Triumphs and MGs use this garage.
During the troubleshooting, when the engine was warm, the coil was removed and a new one inserted. The same poblems were still there. They put back the old coil.
The car was not running well before the service either. The problems started after I had done an engine wash becaus I had forgotten to put the lid back when I filled oil. After the wash the car started as usual. But later on I got the problems.
Both garages have very competent mechanics. They were measuring different things with their equipment for this, and not replacing anything just without a reason. I hope that they will find out what is wrong next week.
1. Since you did wash/spray the engine bay area, the
water may have fallen into the distributor cap
and onto the spark plug wire cavities. Maybe the
coil wire too.
2. Early TD's use the short spark plug (1/2) inch.
later TD's use the longer (3/4) inch spark plug.
Be certain the correct length plug is used.
3. Norwegian winter are severe..! How would you
move around there without a reliable vehicle....?
Do you have a Reindeer....?
4. Keep us informed...
|Raymond, check the distributor cap for carbon tracking. Like DrRx stated make sure the inside of the distributor is dry as well as both boots on the spark plug wires ends.|
|Mike Hart (52 TD 16378)|
|DrRx: Re 2. As I said, the first garage had wrongly put in the short ones, but the second mechanic found this and changed to long ones. All the short ones were black around the tops.|
Re 3: Since I live in the middle of Oslo, I use tramcar and bus, and if I want to travel further, the train.
Mike: The inside of the distributor has been checked thoroughly and several times. As the spark plug wires ends.
|When it starts sputtering, shut it down. Of course in a safe manner, remove the float chamber lids and check the fuel level. The floats should be bobbing in gas. This will totally prove if there is enough fuel, and rule out any tank or line blockage sticking float needles, etc. One thing else to check: it is easy for plug or coil wires to pull part way out of the cap- unscrew the nuts and make sure they are seating well and not burned. Last thought: how old is the fuel? Does it smell like proper gasoline? In the US, our lousy ethanol-laced gas absorbs water and goes bad in a few months.|
|I would also check the points and clean them. I had this problem also and after checking everything else, a simple cleaning of the points solved the problem.|
|Based on what you have already done, and assuming that these things were actually done, I have two suggestions.|
My first is that the valves are not properly operating, due to either a bent or broken push rod, or loose or broken tappet....If the tappet arm is travelling a bit on the shaft, it may be so loose, as to partially come off the end of the pushrod...
Pull the valve cover, and hand-rotatate the engine, and check valve clearances, and look for a bad push rod.
My second thought , is a vacuum leak at the manifold...Easy to check with a small propane cylinder...Open the propane valve (DO NOT LIGHT!), and , with the engine running, see if the escaping propane, placed near the manifold, causes the engine to speed up momentarily...If so, you have a vacuum leak....A bad one, will cause the engine to stumble and spit.
Good luck, and let us know what you discover.
|Raymond, you might want to consider the possibility that you've developed an internal timing problem. Perhaps on the order of a slip of the timing chain, or something to cause that effect. You can probably determine that by carefully checking the valve and distributor timing as the engine is slowly rotated. Good luck. Bud|
|Bud Krueger (TD10855)|
|Edward, we had broken push rods in mind, but excluded that when the engine worked very well at times. It wouldn't, would it, if there was something wrong with valves?|
Bud, I do believe that this was checked.
The mechanic will start working on the car again on Monday. I will be sitting at home hoping for a telephone that tells me the car is running perfectly again. But I hardly dare hoping any more...
|...we had a TR6 come in last night by flatbed...had spark...and fuel.... but wouldn't run....pulled a new rotor out of a new box and put it on...still wouldn't run.... this morning we put another new rotor on (one of the red ones) and it fired right up and ran well.... |
I don't think you would have any of the 'big' things wrong... the water in wiring or rotor or coil seems like it might be where the problem is...really hard to trouble shoot over 3000 miles....
|Hello everybody who have suggested things to check. My car is still in the garage, but they just called me and told me that there was one cylinder with very bad compression. On Monday they will open up and look for everything there. Probably getting expensive.|
|maybe a stuck valve in there giving you low compression, leakage to the crankcase should not give the symptoms you describe I believe. Head jobs are usually cheaper.....|
P.S. Nice talking to you at Rådhusplassen the other week, i was there with my red TF
|Very interested in what they find....Stuck valve would certainly cause lack of compression, as would blown head gasket, or cracked (GD forbid!) cylinder head or block.|
Hope it is a simple fix.
Let us know.
Low compression on one cylinder will not give the symptoms you describe, running one minute, backfiring the next. You didn't point out if it was backfiring out the exhaust or up through the intake (burned intake valve will do that) but I'm guessing the exhaust.
I'd also suspect that a competent British car mechanic would know when the fuel pump is clicking away like crazy, or not making any noise at all, or clicking slowly as normal.
I know it is old fashioned, but I wonder if they used a vacuum gauge on it? A timing light on the coil wire gives a good indication of smooth or erratic ignition.
Maybe it is too late to suggest, but before jumping to rebuild too quickly, see if engine fires up and redo the compression test. I learned as a kid (half century ago), to unscrew plugs a bit, thread them back in, fire up the engine to burn out any carbon broken loose that can wind up on a valve seat, then do a compression check. If I get a low reading, sometimes I'll doublecheck it by running the engine and redoing test... once in a great while, it is right back up to snuff.
Squirting some engine oil down the spark plug hole will often raise compression, indicating the problem is in the rings/piston/cylinder area; no improvement makes the valves more suspicious.
|,Jim, they got rid of the backfiring while I was there. When it was backfiring, it was through the exhaust. But the engine would jump some beats (in Norwegian it is called "fuske". I am not really into the English vocabulary here, sorry). And I repeat, these are experienced mechanics. They taught me to hold on to the fuel pump when turning the key, to check the clicking. |
I guess we will learn in the beginning of next week what has been wrong. I am beginning to miss the car now...
|Interesting link on coils.|
|Mike Hart (52 TD 16378)|
If they got rid of the backfiring, what did they attribute that to?
I'll guess that your "fuske" would be called a "miss" here. If one cylinder has too low compression, it may not fire and the engine idles/runs rough.
Are they pulling the head? ... pulling the engine? Wish I could run over with a timing light, compression gauge, vacuum gauge and a handful of tools.
|I believe they found out what is wrong. My English does not cover car engines, could it be the cylinder head gasket? Anyway, they have now ordered new from Moss and I think they will get it in the beginning of next week.|
do you have the right firing order 1-3-2-4?
Think that the rotor of the distributor turns unticlockwise! If you change 2. and 3. cylinder you have the problem you told.
Not wanting to add confusion into this project
but seeking clarity: My Made-in--England
1950 MG--TD, #0823 has been in Northern California
for 5 decades or more and has thrived using the firing order 1-3-4-2...
( Intake--Compression--Power--Exhaust )
If the head gasket issue is accurate, wouldn't
the car overheat....?
Keep us informed about this mystery, please...!
|headgaskets can leak in many places. When they blow between 2 adjacent cylinders you have no compression or power in either one. when you blow between the combustion chamber and a water path you have exhaust in your cooling system, which quickley leads to overheating, and coolant in the cylinder. other leaks put water in the oil etc...Good luck!|
|It was not the head gasket, either. It is probably one of the cylinders that is not good. The one with no good compression. They wll order a set of pistons. (I hope I use the right words).They have asked a specialist to come and have a look, a man who used to build engines many, many years ago.|
The question of just replacing the pistons, or take out the engine and bore up may come up. They may advice me when they have investigated all cylinders. Anyway, it is already an expensive repair, and removing the engine and bore up will make it even more expensive. So I just said yes to another photography job this summer; the international beach volleyball tournament in Stavanger.
Almost half summer has already gone by, and the MG TD is my only car! Any advise and words of wisdom from you?
|Raymond asked: "Any advise and words of wisdom from you?"|
Enjoy the volleyball games!!
This thread was discussed between 21/05/2011 and 14/06/2011
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