rebuilt 350 problems, suggestions?? Please

[Boiler_guy22]

All,
A while ago I bought a short block 350 for a 1979 chev 4X4 pickup, the engine was built up using parts from an old engine (carb, fuel pump, etc). It has never been ran. Heres the problem, I can get the engine to run when the timing is set really advanced, not even on the flywheel gage like 20º from TDC, the engine runs really rough here but at least it will run. When I attempt to set the timing correctly (8º from TDC) the engine dies. Any suggestions??
thanks to all you gearheads
Ryan

[nova68]

whats the compression on the engine? What kind of gas?

[Boiler_guy22]

Compression looks good (about 150-160) its a newly rebuilt small block, nothing fancy with the gas either, 87 octane.

[molhannah]

All plug wires are correct? Timing light on the the number one wire? Try this first: remove #1 plug rotate crank by hand with socket on breaker bar; rotate until timing marks line up; place a straw thru the spark plug hole so it sets on the piston; now rotate the crank slightly back and forth and see when the straw is furthest out; now see if the timing marks are still at TDC; if they are not you have something wrong; like the wrong timing cover or dampner or may the timing chain is not set up right with the cam. Let us know what you find. Good luck.

[MagicRat]

Excellent answer,

[nova68]

ok what is your compression ratio 10 to 1 or what? sorry didnt make myself very clear

[Boiler_guy22]

Good idea!! The number 1 piston reaches its full stroke at 0 (TDC) on the timing gage. All the plug wires and firing order are correct. The rotor and distributor look good. Could this be a strange carbureator problem? I also wondered if I could be 180 degrees out of time and moving the timing to the current position allows the engine to run, just not real well. I don't know that sounds pretty far-fetched. Thanks for all your help.

[Boiler_guy22]

About the compression ratio, I'm afraid I really don't know (I know you all are extremely disappointed). Its a stock 350 rebuild here so I'm guessing 9:1 but I honestly do not know.

[molhannah]

To see if you are off 180', with the #1 plug removed rotate the crank by hand with one of your fingers in the plug hole. On the compression stroke, you will feel your finger being pushed out, watch for the timing makes to line up. Now remove the dist. cap and check to position of the rotor, it should be pointing to where the the #1 is in reference to the cap.

[Vortec350S10]

If everything checks out OK your dampeners outer ring might have spun on the hub, causing your timing to appear off. If you say that your reaching TDC when it's lined up, this might not be the case. Basically what I'm saying is I've heard of this happening on stock dampeners, and the one on my S10 is way off so I have it timed by how it runs rather than marks.

[Chevy-SS]

Assuming the dampener is good, then this sounds like the timing chain has skipped a tooth. You would need a degree wheel to check, or take to someone who does this kind of stuff.

[silicon212]

Double check the plug wire routing to make sure the firing order is correct.