i hear what sounds like some type of bearing while i drive my truck. I dont hear it while idling, i only hear it sometimes while accelerating. I know its coming from the engine because the noise comes when i hit the gas pedal but the second i let off it stops. I can hear the sound bouncing off cars or trees and coming back to the truck. A buddy told me it might be a pulley or something. Thats what it sounds like sort of. I guess i'm just looking for some input on where i should start looking or what it might be. 87 tbi 350
CK5
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Cannot figure out this noise
- Thread starter Morgan3
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Take the belts off. Run it and see if the sound goes away
Bad U-joints or bad U-joint angles could make noise only while accelerating or decelerating. Of course when you're not moving they will be silent. If it sounds like rocks in a can when you accelerate, that's pinging. Anything related to the belt drive will be dependent on RPM, not engine load. You may be able to work the throttle a little with the hood open to duplicate a pulley/bearing noise.
Had a break from rain and christmas stuff to do that. It wont make the noise idling though and i can never catch it when its making the noise to listen for it. Spun the pulleys by hand and got a little noise from the water pump pulley but thats a new water pump so it should be fine.
It wasnt a u joint, although i did have one go out on me sunday night in 40 degree rain. That sucked. But yeah its a little more of a pinging noise. If its not in the pulleys, what else could it possibly be? I'm going to have time this weekend to get to it and do a few other things
I had something similar that drove me nuts a few weeks ago. Sounded like a pinging and it came and went, mostly happened while driving but occasionally I could hear it at idle. I took belts off and noise was still there. Ended up being a bolt that holds the power steering pump to the motor had backed out and it was captured behind the pulley, bouncing around. I couldn't see it when the motor was off because it fell to the lowest point and wasn't easily visible. It was a SOB to get out...
Had something similar like this a while ago. At idle it was fine, on light acceleration it was hit or miss, but at angles or hard acceleration where my frame would torsion a bit it would sound like loud pings. Turned out my fan shroud wasn't sitting exactly where it needed to be and my fan was hitting it.
I'm going to check for marks on the shroud when i get home. I'm taking any ideas right now though.
It stumped me at first, because when i spun the fan around by hand, it made no sound and no contact on the shroud.
Kain
3/4 ton status
look for marks on the inside of the shroud those fans flex
Kain
3/4 ton status
make sure your motor mounts and trans mount is good and not flexing it will thro off drive line angles and make all kinds of things go wrong
burber1989
Registered Member
You mentioned the water pump is new. I was wondering if the fan could be the culprit... I read somewhere that the viscous coupling should not be turned horizontal even for a minute because there's supposed to be some liquid in it. And if not liquid, something mechanical could easily break in there. There could have been something gone wrong and it just might explain the symptoms when revved .
You also probably only spun the pulleys by hand? I'm thinking you could remove the fan and momentarily fix the pulley so that you can take a short test drive. That way there's no noise from the huge fan and the cooling system can do fine without fan for a moment. If you end up temporarily fixing the pulley without the fan, make sure the pulley on the water pump doesn't work itself loose and destroy stuff. And when adapting something that special, it's usually not a good idea to stick your head anywhere near it when the engine is running.
Also it might come in handy to just have a very short test drive without the belt as i understand someone suggested. But you need to keep it short because of total lack of cooling though and remember not having powersteering so it may not be your first option.
As some of us are fixated on the belt, the tensioner, if broken, may jump back and forth when warm. It creates weird noises and things like that aren't always felt by hand.
Keep it up.
Finally had some time to look at it. Cant be my fanshroud as i dont have much of one left. Previous owner must have took it out to fit the body lift or something.
I used a stethescope and heard something from the tensioner pulley. So i took the belt off and checked that pulley and it has no play on the pulley at all and that pulley actually looks newer than the rest of them. My power steering pump pulley however does have some play in it. I can move it back and forth just a tiny bit. About a quarter to an eighth of an inch. So i will be replacing that when i make my next trip into town
Just took the belt off and made a quick drive. Turns out its not a pulley and its something else. Any ideas if i only hear it when i'm moving and on the gas? I dont hear it when im parked at all
Brakes/wheel bearings?
burber1989
Registered Member
I'm no expert on push rod v8's. Actually i have almost zero experience with them but an engine is an engine.
I was thinking connecting rod bearings if you need to use lots of torque to get the noise. It's just that pinging is not what comes to my mind when describing con rod failure.
I don't think you mentioned anything about transmission?
If you haven't changed oil for a while i'd suggest doing so and taking the old ones into a rather clean container to be inspected. There might be visible flaking that the filter was unable to catch. It goes for both engine and tranny.
I don't know how cold the climate is over there. If it's not freezing, you may want to try stiffer motor oil, like Delvac/Rotella, made for diesel Trucks and big rigs. Not saying it's the one to use all the time, but if the pinging is engine related, it just might show up getting a bit more quiet.
I was thinking connecting rod bearings if you need to use lots of torque to get the noise. It's just that pinging is not what comes to my mind when describing con rod failure.
I don't think you mentioned anything about transmission?
If you haven't changed oil for a while i'd suggest doing so and taking the old ones into a rather clean container to be inspected. There might be visible flaking that the filter was unable to catch. It goes for both engine and tranny.
I don't know how cold the climate is over there. If it's not freezing, you may want to try stiffer motor oil, like Delvac/Rotella, made for diesel Trucks and big rigs. Not saying it's the one to use all the time, but if the pinging is engine related, it just might show up getting a bit more quiet.
Have new pads calipers and inner and outer wheel bearings that i put on a few months ago.
I am overdue for an oil change because i have so many leaks i was gonna do it all at the same time. Engine only has 35k miles and trans only has 10k or so. I appreciate any suggestion though
Kain
3/4 ton status
just cause you did bearings dont mean one cant be bad check em just to be safe
The noise isnt speed related so i dont think it would be wheel bearings. I will check anyways though
