my 93 busted the sub-frame mounts so I didn't drive it for a week. I got the parts started the car and moved it from the grass to the drive. Jacked it up, changed the mounts, lowered the car , told the wife I was going for a drive , started the car and about one second later it hammerd to a stop! I first thought the belt gave way so I jacked it up and pulled the covers off the timming belt. All the marks lined up perfectly with #1 @ tdc. All four cams are in time and in pristine condition. I have only 30 psi compression on 2 cylinders and no knock or wierd feeling when I roll the crank back and forth. What in the world happened??? I havent pulled the heads yet because I wanted to figure out what happened first. I've been doing this a long time , racing and modifying but have never had one stump me like this. ANYONE have an idea? I even got despirate and looked at something my wife suggested I look at!!! I am not pulling bthe heads off till I do a leak-down test and have exhausted all reasonable ideas as what to look at. thanks for your interest. HELP
just lost it!!!!
- Thread starter rvinson
- Start date
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mattsho1993
SHO owner
idk its prolly not it but did you make sure for some reason the dis didn't unplug?
Racer X
SHO Pilot, Retired
How are your Head Gaskets? What's the exhaust gas content in your coolant?
whats the compression on the rest of the cylinders? from my experience if the timing belt has rotated even once the marks on the belt are not going to line up with the cams and crank marks. the cams and crank will line up with the marks on the motor but not the belt. if you get lucky it will line up or be 180 but most time it will not. so that threw me off. you said hammered to a stop. what does that mean? did it lock up? did it just shut off? any noises when it happened?
check the oil.
it sounded like a knock about four times before it quit. again, the timming marks. and piston position agree that it didnt slip time. and no compression on any cylinder more than 30 psi. I havent looked at the coolant yet but there was no coolant in the oil. and the level hadnt changed
pull the VC's and check the cams.
no there is a problem, if you have 30# of compression across your cyl.
did you try starting it after the first time it died?
i ask because there's only three reasons you have no compression.
1) cam or cams are broke.
2) pistons are broke (rod,rings ect)
3) your not correctly using the tester.
its very strange to me that all cylinders are no more than 30psi. and for all the cylinders to drop at the same time is almost unheard of. would you mind explaining how your lining the timing up? not trying to insult you, just want to make sure your doing it right. unless all the rings went at the same time or both head gaskets failed or bent all the valves (non interference engine so that not likely) my bet is on timing. if your positive the timing/valve train is correct the next thing i would do is a leak down test.
during my 3.2 swap i was positive i had the timing right but only had around 90lbs across the board. redid the timing the exact same way and bam! 180lbs across the board. i still dont know what happened the first time.
put a probe in cylinder#1 (firewall side /passenger side) rolled the crank in the clockwise position untill it hit tdc and both cams were in the closed position and looked at the mark on the lower gear, and the marks on each cam gear according to the factory manual
jthod
Mr. Goodwrench
$5 on timing.
did you use the correct timing marks on the belt? (3.0 vs 3.2 on the crank pully)
Is the belt facing the correct direction?
did you use the correct timing marks on the belt? (3.0 vs 3.2 on the crank pully)
Is the belt facing the correct direction?
pitaSHO
Why do I do this to myself?
Line the timing marks from the cams with the rear cam cover. Line the timing mark from the timing sprocket on the crank with the mark on the oil pump. Viola; instant fixed car.
Chris K.
Last edited:
the probe really isn't necessary. it works, but its much simpler to use the marks on the crank gear. im not sure what you mean by "both cams were in the closed position". it sounds like you have the timing right for the belt but im not sure if you checked the intake and exhaust cams front and rear bank. so pull the intake and pull the cam covers off and check them out. take a look at the chain and chain tensioner while your at it. just make sure the pad looks like it has some life on the tensioner.
here is how to time the cams. there will be dots on both the chain sprockets. they'll be on the outer edge near the teeth. they will need to line up with the timing makes on the cam (the holes in the back). they only go on 2 ways, wrong and right. pretty hard to screw up. if your going to time everything back to TDC (thats what i would do) this is how you line it up. the timing marks will need to be flush with the mating surface of the cam covers. the exhaust cam marks will need to be facing down towards the radiator. the intake cam dots towards the intake manifold. looks like this _.. ____ .._ (under dash is the head surface, dots are timing marks). thats basically it for the cams.
this is for timing the belt. line the dots on the gears to the index marks on the dust plate. if the gears are hard to turn you can use one of those rubber strap wrench thingies. line the dot on the crank sprocket with the index mark on the oil pump. install belt. the belt marks should line up with all three points. there should be little to no slack on the belt reaching from the front bank to the crank (as best as you can get by hand). that way all the marks should line up on the belt. all the slack should be on the tensioner side, obviously. thats it! if you do all that and you still have no compression. leak down test.
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