Motor gurus needed.

LaserSVT

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I just need some people to bounce this off of. Some know we just swapped a motor into Sapperfires car yesterday and it just barley runs. I know all exterior components work but doing a compression check shows me 75psi on the drivers side on all 4 cilynders and 0psi on the passenger. Being that I am 80% sure someone has had the passenger head off I assume that the cam timing is way off.

Does this sound feasable? How likely (assuming high) is it that there are bent valves because of this?

Just to answer the questios:
Has spark, has fuel, almost no fire though in passenger side, all sensors, gaskets are new, fuel pump is working right. Internal motor problem as compression test shows.

Being its linear across the bank I would have to assume cam timing. Dont know if its worth pulling apart to try and time it though cause the valves may be bent.

Thoughts?
 
I am gonna agree with your deduction about the cam timing. Thats the only thing that could cause a problem like that.

And yes, they are probably bent.
 
timing chain snapped? just an idea..
I had the covers off on the entire motor replacing gaskets. Checked to make sure everything moved as it should and it did.



Sounds like a poopie day. :(
 
Do a leak down test to see if it's the exhaust or the intake side leaking. I'm not sure how far the cam timing could be off to NOT have bent valves but I would think it would still have contact and sound obvious it it were valve interference. After all you said all the parts were moving, so you might get lucky and only need to re-time the cams?
 
did you guys have the timing cover off, i would have to think you did if you painted it. i cant see a chain being broken if it wasnt broken before you put it in, the compression being that low and none on the pass side doesnt sound right, i know you arent stupid bill but are you using the right gauge and do you have the right fitting threaded into the spark plug hole? did you guys take the timing chains off that motor at any point? did you do head gaskets? if you did i could see the timing being way off but if you didnt touch that stuff i think you have a junk motor. did you guys get to hear it run before you pulled it out?
 
Sucks for sure.

You knew the problem right away when you noticed it was a replaced head.

Sorry man.

Time to deal with the junk yard I guess.:(
Even if its cam timing you get lucky and you can fix it....the bone yard owes you.
 
Jamie, I can figure out how to screw a hose into a spark plug hole and I can even read the numbers AND letters on the gauge. :p
Didn't remove the heads nor did I do head gaskets. Looks like I will be doing head gaskets on his old motor though. I know its a health motor that just needs new timing tensioners and head gasket. Since I know its timing is right I can lock the cams and pull the chains.
 
Jamie, I can figure out how to screw a hose into a spark plug hole and I can even read the numbers AND letters on the gauge. :p

I guess you can only do that once it's in the car?
I've never needed to do it before, so I'm unfamiliar with the process, but couldn't it have been tested long before now?
 
like i said i know you arent dumb, you wanted help, i was asking questions, if you are using the gauge correctly and those are your numbers, tear the engine out, its obviously the reason why it was in the junkyard, because its junk. nothing good comes out of an aerosol overhaul!
 
Oh well, gonna list the bare motor on craigslist and then put new headgaskets on the old motor I guess. Sapperfire has the cam locks so not a big deal, just time consuming I guess.
 
FWIW, I was told if the cams are 180 degrees out of time, the valves will be fine. It is a not so uncommon mistake.
 
What was the verdict of the repair on your car driller.
 
Anyone done a write up on timing one of these? I've done several timing jobs, just not a 4.6dohc yet...

This car will one day be a total rebuild, Bill and I are rolling the idea of opening our own shop, this car will be the guiny of everything I don't know how to do yet, or just need more practice with. I plan on doing a factory moonroof install, body and paint, and general repairs/proformance work, so if I can get this minor hickup of a bad motor behind me...on with the show!
 
You are a hi-jackin MF'er. Ask him in the thread where he posted it, or PM him. :q:q:q:q....

Bitchbitchbitch. Thread over ? has been answered. (Timing chain). So its really not thread jacking anymo'.
 

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