Opinions Thread.....

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Steve welder

Steve welder

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New thread dont ask me why, im F-ing disgusted,,,,I never ever had a car give me the problems this one does, like its possessed...
Latest issue
I removed the rockers, blanked off the carb at manifold and put 5 psi air into a the intake....Wont build up pressure, as fast as air goes in it comes out....raised the pressure and I hear a bad leak..... Air is coming out of every cylinder spark plug hole on the even side, nothing on odd side
Compression on odd side is 185 in one cylinder and 190 in the rest
Compression on even side is low of 173 to 180
I put shop air 120 psi into #7 cylinder......No noise at tailpipe.....Air is leaking into the intake manifold and I feel air coming out of #5
At this point I dont think its a head gasket, I think the head is cracked
No pressure buildup in radiator and no water in oil
I dont know what to think
Any thoughts?
 
Wait a minute this isn't because you have a rough idling Cam and you think it's idling too rough?...
I could be totally wrong here but I think I remember something...
 
you sure all the intake vales are closed on the 'even side" ? OR you flat out have a sealing problem on all your intake vales OR like you said your head is cracked/warped not sealing. Yo u have no pressure or air coming out the oil fill cap right?.
 
Yes
My head isn’t clear today so forgive me
I knew the engine was running right
And now I know why
 
Just pressurized #5
Air building up in intake manifold
Air is coming out of #7 plug hole and slightly out of 3
Tell me I ain’t screwed
Well at least I woke up this mourning lol
 
Steve welder said:
Just pressurized #5
Air building up in intake manifold
Air is coming out of #7 plug hole and slightly out of 3
Tell me I ain’t screwed
Well at least I woke up this mourning lol
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that seems like a warped head or deck surface but id think you'd have air possibly in the crankcase, but maybe not so much if you have good ring sealing. You may just need another head or take it to a machine shop. I would however have both heads either replaced or rebuilt, but if on a budget just doing the one thats broken will do. If you do your own wrenching, what you want to do is pull the head, and straight edge it. The warpage has to be minimal like .001-.003 thousanths of an inch for aluminum. I believe the spec gets bigger for cast iron possibly up to .005 etc. you'd have to look it up. Or pull the head and send it out. Are they aluminum heads? It sounds like they are cast usually doesnt warp much.
 
Piston ring end gap measured with a tape measure? LOL
 
toolmanmike said:
Piston ring end gap measured with a tape measure? LOL
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Ok, now that's funny...but, how many of us woul ddo it under "combat conditions" LOL! actually id eyeball it under combat conditions, I may even throw it together and "see if it runs" under combat conditions LOL!
 
Dartswinger70 said:
that seems like a warped head or deck surface but id think you'd have air possibly in the crankcase, but maybe not so much if you have good ring sealing. You may just need another head or take it to a machine shop. I would however have both heads either replaced or rebuilt, but if on a budget just doing the one thats broken will do.
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Thanks.....The block was decked, no oil burning so im hoping that's ok..... These heads were done and have hardly no miles.....A bad valve would be one thing but leaking into other cylinders is something else
Either way looks like head has to come off.
 
Steve welder said:
Thanks.....The block was decked, no oil burning so im hoping that's ok..... These heads were done and have hardly no miles.....A bad valve would be one thing but leaking into other cylinders is something else
Either way looks like head has to come off.
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well it could be a gasket issue too. parts these days are sketchy at best.
 
Well he knows he has air coming out of places it shouldn't he doesn't need a leak down test at his point. Why would he run around buying equipment that he may only use once in his life when he already knows he's got a problem? thats like telling him he need an oscilloscope to test his ignition when he already knows he has a misifre...

:lol:
 
Dartswinger70 said:
Well he knows he has air coming out of places it shouldn't he doesn't need a leak down test at his point. Why would he run around buying equipment that he may only use once in his life when he already knows he's got a problem? thats like telling him he need an oscilloscope to test his ignition when he already knows he has a misifre...

:lol:
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Exactly, I understand and know that a leak down test is a percentage of air getting past valves, so air entering intake manifold, leaking past intake valves may be excessive or not,,,BUT air escaping from one combustion chamber to another could indicate everything from a blown head gasket in-between cylinders to a internal crack
Im going to test the other bank later on
From what I know, maybe someone else could tell me is its my understanding when you do a compression check and the compression is good, a leak down test with gauges isn't needed....Thats why up to this point I didn't do one
 
You see....in America......we have the right to mock and dispute the most experience person to respond to the question.

Ahh! Just tear it down and find out what's the matter with it.
 
IQ52 said:
You see....in America......we have the right to mock and dispute the most experience person to respond to the question.

Ahh! Just tear it down and find out what's the matter with it.[/QUOTE

in all reality if he has rockers off of it he's half way there. he could have the head off in an hour. air ratchet etc run them bolts out...
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p.s Americans are "ying yangs...":)
 
IQ52 said:
You see....in America......we have the right to mock and dispute the most experience person to respond to the question.

Ahh! Just tear it down and find out what's the matter with it.
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Why? If he does that then we have less entertainment. Dammit Jim, you just hush. lol
 
IQ52 said:
You see....in America......we have the right to mock and dispute the most experience person to respond to the question.

Ahh! Just tear it down and find out what's the matter with it.
Click to expand...


Exactly ! I just went thru this exact thing . Fresh build on a 408 with W2s.
Ran in up and down the road a few times then blew a freeze plug first time I revved past 7k.... Pulled the motor and had everything checked .
Turns out I had ring gap and bearings too tight and 1st machine shop missed the align bore he was paid to do .
I am glad I tore it down just to check for blown head gasket .
All back together now and scheduled for dyno this week .
 
The block was decked. I mentioned this in your first thread. If the decking job is not square, then the intake gasket may not seal. If the intake is aftermarket, it could also me poorly machined, causing the same problem.
 
mbaird said:
Exactly ! I just went thru this exact thing . Fresh build on a 408 with W2s.
Ran in up and down the road a few times then blew a freeze plug first time I revved past 7k.... Pulled the motor and had everything checked .
Turns out I had ring gap and bearings too tight and 1st machine shop missed the align bore he was paid to do .
I am glad I tore it down just to check for blown head gasket .
All back together now and scheduled for dyno this week .
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That's Messed Up. I'd be highly upset! Lol Extremely PISSED!
 
Bewy said:
The block was decked. I mentioned this in your first thread. If the decking job is not square, then the intake gasket may not seal. If the intake is aftermarket, it could also me poorly machined, causing the same problem.
Click to expand...
I tend to go along with this. There's really no guarantees to "fixing" the problem without complete disassembly and measuring everything. If you do fix it without "all that" it will just be by sheer luck.
 
IQ52 said:
You see....in America......we have the right to mock and dispute the most experience person to respond to the question.

Ahh! Just tear it down and find out what's the matter with it.
Click to expand...
Looks like I will start taking heads off very soon....Will start with one side I think is the problem

Bewy said:
The block was decked. I mentioned this in your first thread. If the decking job is not square, then the intake gasket may not seal. If the intake is aftermarket, it could also me poorly machined, causing the same problem.
Click to expand...
One side has no problems, I doubt its the block but of course will check that out.
After yesterday Im thinking the intake valves aren't seating as well as the opposite head
Going to do a leak down test on that head today.....
As it stands im not happy with the rebuilding job on this head(both done same guy different times). It leaks past the intake valve a lot, sure it makes compression but not as much as the other cylinder bank
I have to determine how much is getting past intake valves
 
I made some mistakes, I should have remembered......Looks like no cracks no head gasket issues
Head in question has one bad intake valve I know of. Did a leak down and that cylinder failed bad.....Did one cylinder on opposite head and there was day and night difference
Im Tired of pissing good money away, these heads were just done (at separate times due to one was cracked). All new valves, hardened exhaust seats new springs resurfaced..... The guy assembled the motor, am I wrong for thinking he could have checked the valves first
 
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