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Wedge TR7 engine problem

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johnrip

johnrip

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Thank you to those who replied to my hardly running engine, that occured overnight. I have the compression numbers. 110, 135, 140, 110. What should these be? I have no blue smoke, I have no coolant in the oil, and no leaks. The engine still barley idles, runs better at higher RPM, but is hesitant and some backfiring. Good spark, dry plugs.
 
Compression #s don't tell a full story, but as a rule I look for consistency. So 110#s on all 4 might be better than up and down like we've got. What do you find under the distributor cap? The cam chain on the 7 is relatively short lived and could concievably get so loose as to skip a tooth. Cam cover is fairly easy to get off and allow checking of clearances. It is a frustrating stumper that this occurred while the car was parked, but once you get it figured out it might seem more logical. AAR don't despair, we've all been there and survived to enjoy another drive and you will too. Do you have a service manual for your car? When my TR7FI died it took several weeks of phone calls and research to diagnose and 15 minutes to fix. Good Luck and God Bless
 
Thank you for responce. My mechanic is all concerned about the compression numbers...Do you know what they should be??
 
I have good spark, and the ignition seems OK. I have the lucas distributor, not the one you have on your FI car.
 
The reality is that compression test numbers are just that, numbers. Like was posted above, consistancy is what you are after. There are so many variables that can affect compression test, i.e. cranking speed, whether or not the engine is warmed up, throttles open or closed, etc. At this point, if your mechanic really has his knickers in a twist, a leakdown test might be in order. Still, it is HIGHLY unlikely that a mechanical fault developed overnight. Far more likely you have developed a carb or ignition fault, and that should be able to be diagnosed by a straightforward process of elimination.
 
If the ignition is good then it sure seems like carb would be the focal point. Compresion figures etc can wait. I don't think those numbers would prevent the car from starting and running well.
 
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