QuestionQUESTION: When the engine is at operation temperature and shut off it starts with an idle so rough it dies unless you run it a little while it a higher rpm. It idles fine unless it is shut off for a few minutes.
Thx for the help.
ANSWER: That can be several things. Is there any blue smoke out the tail pipe on first start up? Is there a puff of black smoke when first started when hot?
Blue smoke on a hot start up could be a valve guide problem.
A puff of black smoke is an indication of excess fuel on start up could be a problem with the choke system, float level or the float chamber vent. (the vent system is easy to test by just removing the hose off of the carb for a test start or two.)
Another problem in hot weather is when an engine shuts down the engine compartment gets much hotter and that can boil the fuel in the float chamber to either force excess fuel into the intake manifold or boil most of the gas out as a vapor and thus leaving the float chamber low which takes time for the mechanical fuel pump to refill it.
Try a couple of things, first try running the engine so you know when you shut it off and try to restart it, that it is going to fail. But this time have an electric fan ready and quickly open the hood when you shut it down and have a fan blowing on the carb side of the engine. Then try to restart it to see if that changed anything.
Another test is to remove the spark plugs just before you start the engine in the hot mode that you are sure will result in the bad idle and examine them closely to see if they look either wet or the insulator looks flat black or dirty. The insulator in the plug should look clean and white or very light tan. If they are dirty have them cleaned and gapped and try your hot start test to see if that changed anything.
Let me know.
Howard
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QUESTION: I also have to replace the soft top with the new one that came with the car. It looks like the only trick there will be riveting the new one at the front.
ANSWER: The trick is getting the measurement correct so it is tight when up but not too tight. I never put one on a Spitfire but have done a few MGBs which have the same problem. I was satisfied with two of the three I did but you are somewhat committed when you put that front on and it is very hard to make adjustments if you mess up. I sent every one to a trim shop after that. Yesterday I couldn't even spell mechanic and today I are one, but I still can't even spell "Trimm Man".
Howard
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QUESTION: At the risk of being a pain, how much tranny noise is normal. Supposedly, it was rebuilt about 2 years ago. Compared to what I am used to, it seems noisy. It is fairly noisy in first and second, gets quieter in third and 4th and seems quiet in OD. How much help would a gearlube change make?
Thx.
AnswerCheck the oil to see what was used. Some shops used engine oil to help the syncros work better and got more trans noise. BLM said to use gear oil as the factory said. Most of the British cars were more noisy than other cars in the lower gears but you need to keep an eye on trans oil and if you change it, run it through a paper filter to see if you have a lot of metal in it. Forth gear is direct drive so it and OD will be much more quiet. All the gears are turning but they are no longer under load. If reverse is more quiet than first you may have a problem since reverse is usually the most noisy.
Howard
