Another problem with M135??

[Brad]

You guys are probably tired of me asking on here? I know I am very tired.
So this truck has ran fine since I discovered that clogged gas line. And everything should be all tuned up because we replaced EVERYTHING except the ceramic dist cap which looks fine.
Spent the last couple days going over the exhaust system trying to quiet it up some. Really only welded shut a couple small holes in the pipe and muffler, and putting in new donuts.
After that was all done, would not start! Even when we had fuel line trouble it would always start. Now no start.
Checked and had plenty of gas to carb, but the spark at #1 plug looked mighty weak. Talked to a couple friends and the concensus was that the condenser may be bad, even though it was a new one. Started to change it and discovered the screw that holds it in was nearly out. So tightened it up hoping that was the trouble. NO, still no start.
So we changed back to the original condenser we replaced when we initially thought it was the trouble?
It started right up, but did not seem to run well. Took a road test and it ran, but very little power, bad.
So we checked our point gap, was good at .022 as the manual says.
I had my son turn the engine over while I watched for spark at the points. None there, but a big strong spark jumping from the negative pole on the coil up to the main contact of the coil that is where the dist cap goes in when the cap is on, that is distributed to the plugs?
Is this something wrong, or will this stop when the cap is in place, and then spark will be sent the points?
I am sorry to bother you all with my troubles, but we have no where else to turn to??
Thanks in advance for any help.

 

[Barrman]

Trouble with our trucks and finding answers is why we all come to this site.

The spark at the points is what causes the coil to “collapse” and send hi voltage to the distributor cap and plugs. Check your leads around the points and what could be touching the points. Something is causing the coil to collapse and send spark via an alternating route to the spark plugs with proper timing.

 

[rustystud]

When you were working on the exhaust system did you remove the exhaust manifold ?
For some reason the "governor" keeps popping up in my brain. Have you checked those lines ? The ones from the front of the engine to the carburetor.

OK, now that I got my "wild speculation" out of the way let's get to work.
What does a "Gas" engine need to work.
1) Fuel
2) Ignition (spark)
3) Air
4) Compression
We know we have fuel. You already verified that.
We have spark, but you say it looks weak. We'll get back to that.
Do we know we have "Air" ? Is the "carburetor" working properly, and is the air flow unobstructed ?
We know we have compression, correct ?
So we need to check the carburetor inlet piping and air filter.
Then we need to check the Ignition system again.

Since your truck worked properly after you found the fuel obstruction, we can probably "assume" this problem has come about due to your working on the exhaust system.
Did you use a welder on the pipe ? and if so did you disconnect the battery ?
If you didn't disconnect the battery, you could have fried some of the electrical components.
You should start there.

 

[Brad]

Thanks for the quick responses
To Barman: I been trying to understand how all that works inside that enclosed distributor. After a night of think about it, I think that big spark jumping from the neg pole on the coil to the main oriface at the coil top, is probably actually jumping in the other direction? Each time the points close. I think once the cap is back on the hot spark would then go to the plugs?
To Mr Stud"
I have a full flow of gas to the carb now
I removed the air cleaner duct, the carb horn is wide open. I tried starting fluid, nothing.
Compression is very strong. Very hard turning engine by hand to set points.
Exhaust, I immediatly thought we might have an obstruction and that's why there was no power? But all we did add donuts at the joints and tighten everything up. But we took the stack loose at the muffler and passed am old hose down until it came out the other end.
I had the pipes off from the manifold to the muffler, they are wide open.
I did not remove the manifold. The welding done on the pipe and a small patch on the outside of the muffler was all done off the truck. The patch was over a small deteriorated area and did not enter into the muffler.
The points are not burned.
I am busy with other things today but I think tomorrow afternoon all I can do is put in the last new condenser we have, and see what happens?
If it were a gas problem, wouldn't it start on the starting fluid sprayed into to back of the carb? That is why I think it's a spark problem.
Again, thanks so much to all.
This is a quest I have to get going for my Dad and my Son.

 

[USMC 00-08]

Maybe this will help you.