flatline racing

thek0rn.........did you change oil by chance. I didn't see if you did or not. Just a shot in the dark.

Kennys

I want to see the outcome of this one. I've never heard anything about valve seals causing this but I guess it could. Been rebuilding and machining engines for over thirty years and haven't heard of this. Some of the heads that I have rebuilt from turbocharged diesels don't even have seals. I have seen valve guides and valves so worn that compression would go past them. Doesn't seem likely that there is a problem with the bottom end based on the compression test. Good luck, waiting to hear what you find.

nitrousn

It does?? Please explain how.
The only way any sort of vacuum can be obtained it through resistance like a plugged air filter. If you dont believe me put a vacuum guage on the filter box. The only time any negative pressure will be obtained is from a severely plugged air filter. As long as the filter is good there will never be any sort of vacuum.

flatline racing

A vacuum is produced when air is taken from one spot to another...... You are correct in what you stated....... Those little vacuum guages are junk. A water manometer is the correct way to measure this. There is always a vacuum in the intake tube. Even the best filter ( free flowing ) has a restriction. and also, just because it has a lesser restriction does'nt mean it is better. Behind the compressor wheel has a good vacuum. Kind of like the breather tube on our trucks, why does the radiator get nasty on the back-side when the fan is a puller?

keith

thek0rn

i have changed the oil. the problem started in july, its been changed twice since the first time it happened.

quicksilvr

Not to get off topic here, but it's been mentioned a few times about an engine that has been driven "easy" is there anything wrong with that? My truck has never really towed much.

thek0rn

well i just put 15 pounds presure into the intake, and i have 4 intake valves that are leaking enough air past to see and hear it. i can move the valve stems back and forth, and watch the air leak move around. at 30psi, there is alot of air moving past those 4 valves. so it looks like the head needs to come off at the very least. i will check the bottom end(rings, cyl walls, pistons) once i have the head off and see what the rest of it looks like.

anyone have machine shop recomendations?? i guess ill have it o-ringed and do studs while im at it, since i do plan on bigger sticks and a turbo in the future(later than sooner now).

should i be concerned about doing alot of work to the #53 block. its held up this far, but thats with rv275s and a stock hx35.
another option would be to try and find a complete used engine, non-#53 of course.
whats everyones thoughts???

thumper549

If you remove head..Use new bolts, check for CRACKS !! B4 head work (prone )
a new head was a G some times cheaper..just to buy new

Busboy

.006 to .015 inches will feel like a tremendous amount of play. I would just change the seals without removing the head and carry on.

CamperAndy

I second that and it will not be that much time or energy wasted in the event it does not fix the issue. That is unless this blow by is a good excuse to fire ring the head!!!!!

thumper549

Put a dial indicator up to it,,No guess work

DODGEOG

Thank You for sharing ! I am glade you found your problem . I would like a answer on the short trip question , How bad is it to not get the temp up on the motor . I take my dog to the park about 6- miles round trip . I live in califorina , was thinking of blocking off the grill to get some temp in the motor.
Thank You !

thumper549

An other thought...is 15 lbs enough to hold the valve to the seat ?
and one more you sure the valve was closed ?

nitrousn

The rockers should be taken off when doing that test. Air pressure is also trying to open the valve.

CamperAndy

The test has nothing to do with the valve seat but is a test of the valve stem blow by, which will happen if the valve is open, closed or somewhere in between.