| Moderated by: Greg Fletcher | ||
| Author | Post | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
Brad Pace Member
|
I have a mystery problem with my JH-5. It starts up fine and initially runs good, but once it warms up (after 15 minutes or so) it begins missing, backfiring, and generally sputtering. The more you drive it the worse it gets. I have tried a number of things to diagnose this problem, all unsuccessfully. I thought that the shims may be needing replacement or correction. So I did this, which was a lot of work. I then suspected that I might not be getting good compression, but I have tested this and the compression is fine. My latest thought is that perhaps the choke is sticking and the fuel mixture is too rich, so as the engine warms it cannot handle the rich fuel. But I do not smell a rich mixture and do not notice any unusual exhaust. Last fall I put on new Dellorto's and perhaps there is a problem with these. Has anyone else had problems like this (with the choke or carbs)? Any suggestions? Thanks! |
|||||||||
|
Mark Rosenbaum Member 
|
Might be fuel starvation. Measure the fuel pressure at the inlet to each carb. Pressure should be 1.5 to 3.5 psi. IIRC, Del'lortos prefer 2.0 to 2.5 psi. |
|||||||||
|
Dan Collier Member 
|
I once tracked the problem to the ground wire inside the distributor. The braided cloth sleeve can hide a broken wire. The engine would could idle normal and sputter under load. Just a thought. Dan Collier JH74 14381 2.2L Jensen-Healey Preservation Photo Gallery |
|||||||||
|
Brad Pace Member
|
thanks, I will check it out |
|||||||||
|
Brad Pace Member
|
Yes, that wire is on my list of suspects. It looks very questionable. Thanks for the reply |
|||||||||
|
Rory Clark Member
|
The task to replace the distriburor wire is very simple (IF you pull the distributor) Just use a solid copper 14-18 ga. wire. Can't understand why they cloth covered it. As it worked out I had some Hi-heat resistant covered wire. But I do not think the wire needed to be sheilded. Rory 73-JH |
|||||||||
|
Brad Pace Member
|
thank you |
|||||||||