PDA

View Full Version : SBC engine trouble

enkeivette
07-09-2009, 09:58 PM
Round two.

Fired the motor up, straight headers, let it get hot, retorqued the heads.

The next day I bolted up the exhuast, let it get up to operating temp and set the timing. It was running fine, sounded normal. Turned it off to inspect for oil leaks, fired it back up and the exhaust sounds really loud and poppy on the drivers side. The exhaust is connected by an H pipe, but other than that it is pretty much straight through. I would think this would be an indication of something wrong on the drivers side.

Did a compression test, 130-135 in all cylinders except the one that I replaced. That cylinder is at 115 psi. But that cylinder is on the passenger side?! The low psi could be a result of the scored cylinder wall, a crack in the head, a f'd valve seat or some melted aluminum on the valve. But, all of these things would have existed during the initial and 2nd start up. The loud poppy exhaust note (exclusively on the drivers side) started later. So what the hell could it be? What does that sound indicate? Tomorrow I'm going to pull the blower off so I can pull the valve cover off and watch the rockers moving. I'm thinking it might be a stuck lifter...???
94cobra69ss396
07-09-2009, 10:32 PM
Do you a solid or hydraulic roller cam. It sounds like the exhaust valve is either sticking open or you have it adjusted so that it is staying open during the compression stroke. If that's the case it will get worse as the engine warms up.
enkeivette
07-10-2009, 12:42 AM
All of the cylinders on that side made 130-135 psi, so what are the odds an exhaust valve is sticking open?

Doubt they're adjusted improperly, only run 1/2 a turn of preload. EOIC. Intake Close, adjust the exhaust. Either way, blower and rocker cover are coming off tomorrow... gay.
enkeivette
07-10-2009, 12:44 AM
Btw, is 15 psi within normal range? I thought the acceptable range was 10 psi.

And it's a hydraulic cam.
BRUTAL64
07-10-2009, 10:28 AM
Did you check your plugs? I've had a weird popping sound on one bank and it was just a bad plug. But, with the way your luck has been going........:crutches:
enkeivette
07-10-2009, 11:51 AM
Did you check your plugs? I've had a weird popping sound on one bank and it was just a bad plug. But, with the way your luck has been going........:crutches:

Plugs are all rich fouled, I did drop one on reassembly... maybe I'll pull the plugs out and swap sides.
BRUTAL64
07-10-2009, 12:11 PM
Plugs are all rich fouled, I did drop one on reassembly... maybe I'll pull the plugs out and swap sides.

Put new plugs in. You need new plugs. New plugs would be the way to go.

Get the idea? You should just bite the bullet here. Get the cheap ass ones for testing.

Hell, my engine loves cheap ass Champions.:thumbs_up:
enkeivette
07-10-2009, 12:45 PM
Put new plugs in. You need new plugs. New plugs would be the way to go.

Get the idea? You should just bite the bullet here. Get the cheap ass ones for testing.

Hell, my engine loves cheap ass Champions.:thumbs_up:

OK, talked me into it. You should be in parts sales, haha.

It sucks working on an $8K motor with no money.
BRUTAL64
07-10-2009, 01:08 PM
OK, talked me into it. You should be in parts sales, haha.

It sucks working on an $8K motor with no money.

Yea, no money. I live that tune. I checked what "TECHs" get paid and I get 1/3 what the average is. Yep, no money sucks.:suicide:
Vettezuki
07-10-2009, 03:23 PM
Yea, no money. I live that tune. I checked what "TECHs" get paid and I get 1/3 what the average is. Yep, no money sucks.:suicide:

Did you use salary.com, or some other resource. Fields matter quite a lot.
BRUTAL64
07-10-2009, 03:37 PM
Did you use salary.com, or some other resource. Fields matter quite a lot.

Are you saying I'm not worth 3xs what I make now?????:mad:



I told you what I make.






:D
Vettezuki
07-10-2009, 04:13 PM
Are you saying I'm not worth 3xs what I make now?????:mad:



I told you what I make.






:D

You make 1/3 of what other techs make, that's all I know. I can tell you this, project managers/supervisors (me) make a huge spread according to industry. Basically the more "fun" something is, like recreational car stuff, some forms of entertainment, the less you make. The more high stress pure industrial/technological/economic a field is, the more you make. Even within a field, one company can easily be 5-10% higher/lower than a competitor.
BRUTAL64
07-10-2009, 04:59 PM
You make 1/3 of what other techs make, that's all I know. I can tell you this, project managers/supervisors (me) make a huge spread according to industry. Basically the more "fun" something is, like recreational car stuff, some forms of entertainment, the less you make. The more high stress pure industrial/technological/economic a field is, the more you make. Even within a field, one company can easily be 5-10% higher/lower than a competitor.

I guess I feel a little better. Thanks for trying.:drink:
enkeivette
07-11-2009, 01:12 PM
Yea, no money. I live that tune. I checked what "TECHs" get paid and I get 1/3 what the average is. Yep, no money sucks.:suicide:

My friend who has been working at Mercedes Benz for 5 years makes less than 3x minimum wage, so I doubt that. But this thread is about my motor, no hi-jacking.

Pulled the plug wire off the cylinder that was scarred a bit that I had to file down. Noise stopped, going to replace the plug today, but I doubt that it will fix the problem.

And I doubt that the piston is the problem because it cranks out 135psi... :confused:
enkeivette
07-11-2009, 05:31 PM
Loose exhaust rocker. Would have found it two days ago if I didn't have to pull the blower off to get to the rockers. :suicide::thumbs_up:
Vettezuki
07-11-2009, 07:08 PM
Loose exhaust rocker. Would have found it two days ago if I didn't have to pull the blower off to get to the rockers. :suicide::thumbs_up:

How'd that happen? Falty/loose threads or did you just brain fart?
94cobra69ss396
07-11-2009, 11:07 PM
Good to hear. So how is it running? Have you pulled some timing out so it doesn't happen again?
enkeivette
07-12-2009, 04:41 AM
No idea how it happened, like I said, motor sounded fine for about 20mins. Maybe the pushrod was binding? Giving a false sense of adjustment and after some run time it kicked free? I have poly locks and stud girdles so I doubt it shook loose. It would have to break free from both.

Don't know how it's running. Letting the silicone dry. Back of the lifter valley was spitting out oil. If I fire it up tomorrow and it doesn't leak oil, I'll drive it over to Ben's place.

Timing is at 10 initial, 28 total. Down from 34 total when it popped, or 36 NA. Still need to hook up the LM2 and f with the carb.
94cobra69ss396
07-12-2009, 02:32 PM
No idea how it happened, like I said, motor sounded fine for about 20mins. Maybe the pushrod was binding? Giving a false sense of adjustment and after some run time it kicked free? I have poly locks and stud girdles so I doubt it shook loose. It would have to break free from both.

Don't know how it's running. Letting the silicone dry. Back of the lifter valley was spitting out oil. If I fire it up tomorrow and it doesn't leak oil, I'll drive it over to Ben's place.

Timing is at 10 initial, 28 total. Down from 34 total when it popped, or 36 NA. Still need to hook up the LM2 and f with the carb.

The pushrod might have been caught on the edge of the lifter when you adjusted it, I've done that before. I've also had the poly locks come loose on the Chevelle before so that's also a possibility.
enkeivette
07-13-2009, 01:39 AM
The pushrod might have been caught on the edge of the lifter when you adjusted it, I've done that before. I've also had the poly locks come loose on the Chevelle before so that's also a possibility.

Must have been on the ridge of the lifter, I have stud girdles too. So those nuts ain't movin.