Annoying squeak at low revs

[mikeauton]

I seem to have an annoying squeak coming from my engine at low revs, it may well be there at high revs also and I am possibly just not hearing it?

I thought it might well be the drive belt, so swapped that out. However the problem persists. It sounds like it is coming from the very bottom pulley wheel, but it is hard to be sure.

Anyone else had this issue? Any ideas on a possible fix?

I am about 3 months off doing my annual/100 hour service, but dont want to wait until then to sort this out.

As ever, any help or advice greatly appreciated

 

[skydiveD30571]

Re: Annoying squeak at low revs

Check out this thread.

Basically, check that your pulleys are all in-line especially the power steering pulley. It seems to be fairly common on the 4.3/5.0 engines around this year that the PS pulley tilts forward or backward and causes the belt to rub on the pulley walls, creating a squeak. There are a few other threads where the same noise was a result of this. I'd check that out first.

 

[mikeauton]

Re: Annoying squeak at low revs

Thanks Skydive, I really appreciate your input. You helped me with my last problem on the impeller and you were 100% correct.

Will go do some exploring now and see what else I can find out........

 

[mikeauton]

Re: Annoying squeak at low revs

OK read your thread - BIG eye opener. I am pretty confident the noise is coming from the power steering pulley. Will remove the belt and do precisely what you did with yours and will report back on my findings.......

Like you, my engine has had lots of personal love and attention, so having this squeak after all my work is well - bloody annoying!

 

[mandmj]

Re: Annoying squeak at low revs

One way of finding squeaks like this one is to use an automotive stethoscope. That will help if it is a bearing, etc. If it is a belt squeak, you can better localize it my using a piece of heater hose about 3ft long or so, and holding it up to your ear, while placing the other end of the hose at differernt points on the front of the engine. Loudest spot is likely the culprit. It may help to plug the other ear to help you focus on the sound from the hose.

 

[mikeauton]

Re: Annoying squeak at low revs

Update - problem now fixed I simply removed all 4 power steering pulley bolts, then refitted them and the drive belt. Very clearly it is the bolt at the very top which is critical, on my engine I noticed that in fact it does not bolt securely back in place and suspect this was a core part of my problem. I refitted a slightly longer bolt to see if I could get this to bite better, but no joy. It is all back together and running perfectly, but I cannot leave the bolt the way it is.

As I see it, my options are 1. Buy an even longer bolt and see if this bites better 2. Re tap the thread up one size or 3. Use some thread locker on the existing bolt (never used it before and it does concern me if/when I have to take that bolt out again?

Any other thoughts or suggestions would be appreciated. I have little doubt this is a very common problem on these engines and others.


PS - Was chatting to my neighbor who has a Volvo Penta 5.7 GXi, he also made the mistake of leaving the flush hose top off the other day and ended up over heating the engine! Glad I was not the only one, sure there are countless others who have done the same

 

[Grub54891]

Re: Annoying squeak at low revs

Quick check of a belt squeak vs pulley/bearing squeak is to sprinkle a bit of water on the belt. Squeak vanishes for a few seconds,belt is either bad,or alignment issue. Noise continues, bearing issue.
Grub

 

[djpeters]

Re: Annoying squeak at low revs

Just to give another possibility for others reading this down the road...

I had the raw water pump pulley ('95 3.0gs) start separating. The two sheaves of the pulley are spot welded together in 4 spots. One of the spot welds let loose one day and it began making a loud chirping sound. I first thought something really bad happened internally to the motor as we were running WOT at the time. We were on vacation so I took off the pump and went to the local dealer and they said they never saw that happen. Of course the pulley only comes with a new pump but I was able to get someone to drill a hole by the bad spot weld and I screwed it back together. Once I was back home I added three more screws evenly spaced and she's as good as new.

 

[mikeauton]

Re: Annoying squeak at low revs

Grub - I like your belt squeak test and will try that another time for sure.

 

[Grub54891]

Re: Annoying squeak at low revs

Just used the water trick today....yup belt squacking!

 

[mikeauton]

Re: Annoying squeak at low revs

Just wanted to post another small update on this one in the hope it will help others out. The angle of the pulley wheel seems to cause the belt to squeak, if you look down on it you can clearly see where the belt it just a little too far over and thus rubs on the edge of the wheel.

To fix this permanently, I put a washer on the other side of the top bracket, this corrected the angle enough to stop any squeaking at all. I also fitted another washer with a new 10mm bolt I used to replace the 3/8 bolt which was not treading properly.

We ran the boat all day yesterday and it was perfect, not even a little squeal :joyous:

 

[skydiveD30571]

Re: Annoying squeak at low revs

Sounds like the same problem. Great to hear!