Everything hooked up, no wet plug? TBI 350 not vortec

[RHamill]

Put the engine at TDC and do a cylinder leakdown test.

 

[lkfldredneck]

And you have proper compression?

Yep. its 125 PSI (Yes, i know thats low) but after every cylinder head rebuild we've done its been lower than normal, and every time its been around 120-130. even if it was low compression (ie. 100) it would still spit and sputter. our plow truck (86 with a 305) has 1 fouled plug and runs at 110 PSi compression.

 

[RHamill]

Check voltage on MAP sensor while pulling 20 inHg of vacuum, should be 1.1 volts.

 

[lkfldredneck]

Check voltage on MAP sensor while pulling 20 inHg of vacuum, should be 1.1 volts.

Thanks, ill check tomorrow

 

[SAATR]

Sounds like a no spark or ignition timing issue to me. You're getting air and fuel, you have compression, your valve events are close enough to give you decent compression. I find it highly unlikely that you collapsed all of your lifters, especially given your compression test results. If it was a valvetrain issue that wasn't allowing enough air to be pulled in to start, you wouldn't be getting good compression numbers.

 

[lkfldredneck]

Sounds like a no spark or ignition timing issue to me. You're getting air and fuel, you have compression, your valve events are close enough to give you decent compression. I find it highly unlikely that you collapsed all of your lifters, especially given your compression test results. If it was a valvetrain issue that wasn't allowing enough air to be pulled in to start, you wouldn't be getting good compression numbers.

If we didnt have spark, but the cylinders were getting fuel, the plugs would smell like fuel. only 7 and 8 smelt like fuel, and when we turned it over without any plugs in, 7 and 8 leaked a little fuel and there was some fuel on the manifold adjacent to 7 and 8. 7 and 8 only smelt like fuel after we backed the rockers on the driver side off 3/4 turn

 

[slippy3002]

I'm betting on improper valve lash or collapsed lifters.

When you set the lash, you must do each cylinder at TDC. They should be 1/4 turn past zero.

Sent from Rob's MeMo Tab!

 

[lkfldredneck]

I'm betting on improper valve lash or collapsed lifters.

When you set the lash, you must do each cylinder at TDC. They should be 1/4 turn past zero.

Sent from Rob's MeMo Tab!

We did that. im hoping to g0d its not a collapsed lifter

 

[SAATR]

If we didnt have spark, but the cylinders were getting fuel, the plugs would smell like fuel. only 7 and 8 smelt like fuel, and when we turned it over without any plugs in, 7 and 8 leaked a little fuel and there was some fuel on the manifold adjacent to 7 and 8. 7 and 8 only smelt like fuel after we backed the rockers on the driver side off 3/4 turn

How did adjusting the valves out on the driver's side effect fuel getting into a cylinder on the passenger side?

 

[IOWNJUNK]

If you tighten the rockers down too tight you can get to the point where your valves stay open all the time. Compression would be low (if any) and you would not get fuel to those cylinders.