Help! Developed a new problem.

[mustang652]

Developed a new problem. I've spent the past several weeks trying to get my car ready to convert to the 3x1 Offy andn cam upgrade. Background is that I've done a lot of time doing low RPM ideling while I checked out the rebuilds on the carbs and other related systems and some short drives to check out street use. Yesteday I started having a serious miss. Traced it to #5. Cleaned plug and used spare plug with no improvement. I'm getting fire at the distributor, at the spark plug cap, and even pulled the plug, put spare plug in the cyl to maintain compression and checked, and am getting fire on the plug while removed from the head. Have got betwen 6 and 8 k on rebuild from seven years ago. Got any ideas of what could be the problem.

Additonal notes: Checked oil, no foam or water, but do have a seep somewhere around #1 on exhaust sideand or thermostat housing. Hope to get car to shop in a couple of weeks to install new head, cam and rockers.

 

[rbohm]

8) do a cylinder leak down test, i think you might have burnt a valve.

 

[mustang652]

Thanks for the response. Though not to familiar with the inner workings, I was afraid that that would be the answer and hoping not something worse. If it's hopefullf no more than that, I had planned on having the new head built up and installed by the end of July.

 

[Anonymous]

How old are your plug wires. A wore out plug wire will seem to work just fine but won't carry a load. May be wish full thinking but easy enough to check--warmed up and running, open the hood in the dark and see if you see any arcing aroung the wires-usually at 1 end or the other althiugh i have seen them arcing in the middle to things like dip stick tube etc. I recently had to change out some wires that only had a few K on them when all of a sudden performance went south all of a sudden. Opened the hood after runing an erreand at night and it looked like a Christmass tree under there. Accel wires less than 2 months old.

 

[JackFish]

Opened the hood after runing an erreand at night and it looked like a Christmass tree under there. Accel wires less than 2 months old.

Why would new wires do that? Bad ground?

 

[mustang652]

Thanks, good and inexpensive idea. Wires are only a couple of month old Petronic 8mm "U" cut to fit, but I'll check after dark and see if I can spot a problem. Could be possible that I made a bad cut or poor fit on a boot as this was my first try at making spark plug wires. Since I cut them a little to long, I'll try swaping a coule out and see what happens as well.

I'm not familiar with the cylinder leak down test. If I had the tools and knowledge, I'd give it a try even though as soon as I get my parts in from Mike, I'll have it in the machine shop for the milling and valving of the new modified head, a new cam and adjustable rockers.

Does anyone else get the feeling that it seems like every time you spend some money on one of these old cars or trucks, something else deliberatly breaks just to see you pitch a fit and try our patience.