Thread: Chevy 350, zero compression. engine not starting

Tweet

Originally Posted by firebird77clone

I've never paid much attention to where the dizzy rotor is pointing.

Most manuals will show the 5:30 position (rotor pointing toward #1 plug). If you phase the rotor at the same position every time, you can tell where you're firing with the dizzy cap off as you turn the crank. I just got used to it when I was a kid and have not done it any differently through the years. Thank you for your input.

.

I believe we have confused the OP with too much information at this point.

With the timing chain marks lined up correctly, if he follows "firebird77clone" method in post #15, his distributor and ignition timing should be close enough to fire. However, as "techinspector1" said in post #6 (at the end), the valve lash needs to be set correctly first. No compression on all cylinders is usually valve lash too tight.

Before trying to start the motor, back the lash off until slightly loose at the rockers and re-test compression, if compression comes up to near desired results, reset the lash correctly and the compression problem should be solved (re-test compression after re-setting lash to be sure).

Once compression is correct, you can then move on to timing and firing the motor. No amount of fuel, timing or spark will fire a motor without COMPRESSION..

So--you haven't said if you checked the compression yet??????

And there lays the problem (post #3).. LOL

so did all of the above and decided to recheck the rockers before I started.. found number 8 bent... ran to napa , replaced it. The others look ok but I think the issue is the rebuild mechanic used roller rockers, that are non-self aligning... and I don't see guides on the head anywhere and several of the rockers move on the roller part way over. I dd notice on the two rods I pulled have a shiny spot where they are rubbing on the head. They sure don't stay centered. By the way these are vortec heads...

Originally Posted by JbRat

I think the issue is the rebuild mechanic

You may have said it all..

vortec heads had longer valve tips and rockers with raised guide rails to stay centered

First...Thanks !!! to everyone for their info.



so it has compression
The dizzy was installed and timed ok per the procedure referred to.
and it started... I ran to to about 2200rpm then shut it down
I have a severe oil leak at the head to timing to oil pane so will pull that down and fix

Until i figure this rocker issue I won't run it again...

Chevrolet Performance 12495490, Chevrolet Performance Rocker Arms | Chevrolet Performance

Thanks Jerry,

Will these work with the rods I have now? Look to be 7.79 long.

I was also told I have a stage 2 cam, but when pressed for specs I can't drag them out of the builder.

I have read there is little advantage to roller rockers so the above makes sense, especially in a street rod type of application...

not much will fit under those center bolt valve covers
Pushrod length???? hard to say

Originally Posted by techinspector1

Most manuals will show the 5:30 position (rotor pointing toward #1 plug). If you phase the rotor at the same position every time, you can tell where you're firing with the dizzy cap off as you turn the crank. I just got used to it when I was a kid and have not done it any differently through the years. Thank you for your input.

.

Sounds good, I'll give it a try next time.

Originally Posted by jerry clayton

not much will fit under those center bolt valve covers
Pushrod length???? hard to say

I have high valve covers so should be ok.

A picture is worth a thousand words...

rockers misaligned...

Mechanic says they will self straighten... this is after about 2 mins of running at 2000rpm