cubanprince1

My tranny is making a noise that sounds exactly like a rod knocking.............I got under the car and its coming from the tranny. When u turn off the car the noise just sorta speeds up and dies....
Theres also a noise coming from my valve cover. On the passenger side. Sounds like injectors but my friend said it sounds like lifters or something loose in there. It sounds like static but slowed down.......Help me please.....
Its a 91 - 94 BB with no lifters.




Norlandt

RubberBerner

well it has "lifters" but they call them rockers, they're hydraulic and aren't adjustable, it still could hit your valve cover if the spring is bad, or if it cracked and broke, i'd open her up and see what the deal is. You gotta tell us what kinda tranny ya got in her, manual or auto?

cubanprince1

Its a b15 manual tranny. From a 2000 - 2001 sentra se special edition with lsd. It sounds just like a rod knocking. Its got me all freaked out. The car is there idling and u can hear it but when i got under the car it was just coming straight from the bottom of the tranny. If u get next to the driver side wheel (where the tranny is) u can hear it but if u put your ear next to passenger side wheel u wont hear it.

Epstein

Well, if the noise in the tranny matches the revs and is independant of clutch position, then logic would say that it's related to the flywheel/pressure plate/throw out bearing. Come to think of it, a nasty TO bearing would probably make that noise. Especially if the clutch cable was adjusted wrong and holding it against the pressure plate. This is only speculation, though.

For the noise in the head, I'd check your upper timing chaing guide. People usually remove them, as there aren't any drawbacks. I've actually heard the chain dragging on the guide before on a GTi-R. Also, make sure that the oiling rails in the head are working, and you're not starving a lobe of oil.

cubanprince1

Ok, me and my friend (madex) got under the car.....we made some observations and stuff and we figured out that when u hold the clutch pedal in the noise seems to go away. Hmm....so this has to be the tranny. Last night i went crazy and got pissed off real bad and took it out and got on it. While doing this i found out that theres something wrong my my boost controller or the installation. It hit 15 - 16 psi on me. Thank god i was keeping an eye on the boost gauge. hehe lol. I changed the oil this morning to mobil 1 synthetic 10w - 30. I have run it today and the noise remains the same. Question: If its a spun rod (god forbid) wouldnt the noise get louder with beating on the engine? Also, the noise coming from teh tranny does seem to go along with the engine speed. Thanx for the help guys.








Norlandt

Epstein

If the noise stops when you press the clutch, then it's definitely the tranny. Hmm, rod knock noise from the tranny... I'd have to say it's a missing tooth, or something along those lines. I've had bad input bearings make a 'shhhhhh' noise that I could turn on/off with the clutch pedal, but no knock sounds.

If it's rod knock, the sound at idle is uneven. cl, cl, cl clack, clack, cl, clack, etc. Reving it in neutral should net you a consistent stream of clacks.

If it's coming from the tranny and the problem is on the input shaft side, then it will match engine revs (as long as the clutch is out).

I don't have a lot of first hand experience with rod knock, but if you put in really thick oil (20W50 or something) wouldn't that change the sound of the rod knock? And on that line of though, wouldn't that change in sound (or no change) be a pretty good indicator if a knocking sound was coming from the bearings?

cubanprince1

Hmm....well, its sorta like an uneven stream of clacks but they go away when u press in the clutch. They seem to somewhat match the motor rev's but u can barely if not hear it at all when u rev up the motor. You can really hear it at idle. Also, you seem to be able to hear it more after the car has been ran some.But when you press in the clutch they do seem to go away......hmm....interesting.....I do appreciate your help epstein. You have helped me alot.