94 cutlass supreme 3.4 with engine knock

[94cutty3400]

1994 3.4 engine knock

well, let's see if this works.

hope someone can get some use out of it...

http://s173.photobucket.com/albums/w79/ehh1971/

[grandprixgtp_91]

u said u changed the rod bearings. were any of them spun? did any look scored? that sure sounds like a rod knock, it also doesnt sound to be running right, maybe the timings off, have you checked that? it also could be the timing chain tensioner too, when mine went out it sounded similar, its wierd that it only does it when you rev it up. what kind of oil pressure do you have?

Jake

[grandprixgtp_91]

acutally now that i think of it my grand am sounded like that when the flexplate cracked in it. did u unbolt the torque converter and run it?

Jake

[94cutty3400]

we have had this thing apart 3 times checking rod bearings. i am sick of this car. i got it cheap and it has been a nightmare from the first day we started working on it. we did the plastigage thing, yet no one said it had to be done without oil. so we did it again. found nothing over .002, they were not all the same though.

i was told the car had a rev limiter. the motor is shaking because it is just hanging from the support and a floor jack underneath braced onto a motor mount. or it was supposed to be, i noticed in the video, the jack is down.

i am about ready to sell this car. i can still sell it easily for what i have in it.

i am not sold on the plastigage stuff. we have all standard bearings on the rods. yet, one has .002 of play i would say. sounds like to me, the crank needs to be taken out, have the thing turned to make them all fit into undersized bearings, and put back together. this has been a 2 day project and it has turned into 5 weeks so far.

no bearings were spun. none were scored. have not checked timing, i am having enough problem getting motivated to work on this thing anymore! oil pressure is fine, a little over half on the gauge.

if i could just fine another motor and do a swap, life would be a smidgen better. local junkyard wants $700 for a motor with 90 day warranty. or i could go pull one myself and get a motor for $99 with no warranty at all.
i am monitoring ebay for a car/engine that would work.

i have a new set of oversized (.025mm) rod bearings and a standard set of main bearings brand new in the package. supposed to be putting them in sometime soon.

[grandprixgtp_91]

well plastiguage is pretty accurate, in school we measured the old fasion way which took forever and then used plasti guage and every time it gave us the same reading as manually measuring it. so i dont doubt the plasti guage, as long as you used it correctly. but i would definatly not use oversized bearings, or you can kiss the motor goodbye, spec on bearing clearance is .0008 - .0025" so if you say it was .002" then your safe, adding any more material and its not gonna get enough oil and sieze. and to get that crank out , you mght as well drop the motor. you will save time, trannys gotta come out, then the big aluminum timing cover on the side has to come off, along with the timing belt and accesories. its a huge job, and it is possible that it could be main bearings, but i doubt it, half way on the guage for oil pressure on a cold motor is kinda low for this motor, when cold, it should read 3/4 and almost full on the guage when u snap the throttle. i really think you should unbolt the torque converter and fire it up, its a 10 minute job and will rule out the flexplate and the tranny which can both make nasty noises. and yes the car does have a rev limiter, 3000 rpm, when in park or neutral if you try bringing it past 3000rpm it will just bounce off 3000, going up and down.

Jake

[94cutty3400]

sold this car. it is now someone else's headache. i knew better than to veer from the blue oval...lesson learned.

[latemodelnewbee]

I guess he took the easy way out, because with fords they circled the problem. Just look at the emblem

[93Oldsdroptop]

I guess he took the easy way out, because with fords they circled the problem. Just look at the emblem

Hilarious!! Agree 150%!!