Engine/Transmission (1994 - 1998) Very strange noise from engine

[RALLER]

Screeching sound like idler bearing. Removed belt & noise still there. Couldnt pin it down with stethascope. Heater hose TO ear, same results. Ears point to area to rear of alternater. Pulled front cover, thinking KDP pin fell out and grinding on timing gears. Pin still in & i made a block plate for it. On cold start up, No noise for 30 seconds & the screech sound comes in. This has me stumped. Would appreciate some advice. Truck is a 3500 drw, auto. Not coming from turbo. Thanks. BOB ALLER LAS VEGAS NEV.

 

[MMcCallie]

I've been hearing a screech as well that I've assumed was from my fan belt. When I drive by buildings it sounds like my brakes are squealing even though I'm not using the brakes. I just had a new alternator bracket built. I'd never had a belt squeak when shutting the engine off but I do now. I'm curious to find out what your noise is.

 

[RALLER]

Strange noise

Noise is at idle 750rpm. Goes away at 900rpm. I have boot off turbo and its quiet. Listened with stethascope to starter, power steering pump, vacume pump, and injection pump. Oil pressure is normal. Crank up engine, no noise, 20-30 seconds later, screech noise comes in. I would really appericate some in put. Thanks BOB ALLER

 

[BigPapa]

Bob, since it's quiet with the belt off I really don't have any idea unless it's an exhaust leak???



MMcCallie, I had the same sound you mentioned and thought it was the alternator bearing. Ended up being the A/C compressor clutch. It has 3 flat springs on it and 2 of mine had broken and the clutch plate was constantly rubbing on the pulley.



Scott

 

[DValentine]

Do you have your AC on. The accessories come on about that time frame after start up. I have heard my AC clutch kick in 15-20 seconds after start up. You may have an AC pump problem.

 

[Joe G.]

Check intercooler boots for cracks and torn places.

 

[tp0d]

Rear of alternator... hmmm

Possible oil pressure regulator squealing as the oil passes thru?

I`m not sure if this is an easy check, never messed with mine yet... its possible for a regulator to squeal like that though (i`m a plumber, I see squealing reg's -all- the time)

good luck

-j

 

[AKAMAC]

Check the end play of your turbo.

 

[RALLER]

Problem solved. I noticed noise came in as oil pressure came up off idle. I listened with a heater hose and it seamed to be coming from the oil filter housing area. Probly the oil filter bypass valve or pressure regulater just as TPOD thought. Thanks everone for your help. I needed it. I changed oil & filter (Delo 400 CI4). I think i will cut filter open as it seemed a little heavy. Used to use Rotella CI4, Did 1 oil change with CJ4, and oil got real black. Next oil change was Wally World CI4 - 3500 miles and it was real dirty, Prob ably cleaning up the engine. This time it got Dello 400 CI4. Started up and noise was gone. I sure appericate TDR. Later BOB ALLER

 

[tp0d]

glad to hear you found it. .

now I gotta deal with a GEN light on my dash... sigh. . it never ends. .

-j

 

[RALLER]

IPOD Gen gets its triger signal from crank senser. Check electrical conector just above water pump. BOB ALLER