Fast Eddy,
I can relate to the problems you talk about with the fuel system, I see happen it on the heavy equipment sometimes, However on this rig when we built the motor we also cleaned the tank and fuel lines, swapped in a new pump & screen and put on a new filter and we filled her up with new gas.(Thanks anyway- it's good advice! <img src="/forums/images/graemlins/kewl.gif" alt="" />
Me and a buddy, who stopped by to offer support (and hide the new box of bullets I just bought) got to talking about the problem I am having and we came up with a possibility, <img src="/forums/images/graemlins/scared.gif" alt="" />
If the ignition timing has to be advanced so much to make it run half decent, could the crank to cam timing be off, even if the marks are dead on? (say some previous owner swapped on the wrong crank gear) If this was true then the piston would be to far up the cylinder when the distributor fired the spark, and the combustion would technically be late (as in the timing be retarded)and the intake stroke would be shorter as well. This could explain the low power and popping when the base timing was set to 5 degrees. We wondered if we moved the cams one or two notches to the right technically putting the piston lower in the stroke, we might get our power back as well as our vacuum. (Note: No alcohol was injured or killed in the making of this theory!) <img src="/forums/images/graemlins/shame.gif" alt="" />
Doing this shouldn't hurt anything as this is a 0 interferance engine.
Before I got all crazy with theories I decided to make a few more practical checks,
1) Compression test: 4 of them checked @ 135 psi and 2 checked at 150 psi Spec is 130-150 psi with 20% max between them (The 20% is a rule of thumb thing) Based on the fact that this is a fresh engine with only about 4 hrs total run time, I think the results are fine.
2) Vacuum leaks: All the vacuum lines are new but thought, "Better safe than sorry"! I don't know how y'all
check for leaks but for me it's shaving cream <img src="/forums/images/graemlins/notooth.gif" alt="" /> (Not the gel crap, the good old fashion white fluffy stuff, a vacuum leak will suck a hole in the foam, hence a leak) I sprayed it on all the hose connections and the intake gaskets, ( I left the engine running and washed her down with electrical cleaner as a back up test) no leaks.
Well that left our conversational timing theory. I stripped down the front end (I'm getting pretty quick at it!) and rotated the cam pulley's one tooth to the right. Started her up and set the timing where I had the best running and most vacuum (it came up to 17psi from 15psi previously) Stall speed raised to 1700 from 1500. Acts like an improvement but the jury is still out.
Tomorrow, I'm going to go another notch on the cam teeth and see what happens. One thing I haven't done is reset the distributor rotor. When I move the gears one more tooth I will check how it lines up and may move it to correct for the adjustment.
On a side note: I decided to move the cam gears instead of the crank gear because the cam gears are a finer adjustment, the cams' turning one rev to the cranks 2 revs.
I'll let y'all know how it turns out. <img src="/forums/images/graemlins/confused.gif" alt="" />
