Squeal/wail from the front of the engine

[Bagpussawake]

Hi all,

On my way home from work yesterday, a couple of junctions from home a sort of squealing wail started from the engine. It sounded similar but a bit different to an alternator belt slipping but wasn't affected by electrical load. Varied a little as the engine revs increased from idle but seemed constant after about 2000rpm.

I had a listen when I got home and decided it was maybe the alternator belt so on Saturday changed that and the power steering belt as you have to take that off anyway to get at the alternator one.

I checked the timing belt tension and it was fine (about 53-55lbs on an OptiKrik 1 gauge). The belt and tensioner were replaced about 2 months (<1500 miles) ago.

Went for a run and once warmed up the noise was back.

I've had a listen with a long tube and think now the noise is from the Aux pulley/cambelt tensioner area.

If I spray WD40 as in this thread:
http://www.lotusexcel.net/phpbb/viewtop ... f=7&t=3991

and it makes no difference, will I have damaged the cambelt and still need to change it?

If it does make a difference, indicating it is the tensioner, can I just change the tensioner on its own? The belt still looks brand new to me...

Sorry for the long post , just trying to give all the relevant details

[AndyC]

The belt may look brand new, if you don't know when it was changed just replace it. The tension is specified for a new belt, one that has been run for more than a few hundred miles will be quite different (lower) as the belt will have stretched slightly, so tensioning a used one us asking for issues.

[Bagpussawake]

I totally agree about not chancing an unknown or older belt but I got the cambelt and tensioner changed about 6 or 7 weeks ago so the belt only has <1500 miles on it....

I can't really afford a new belt every 2 months!!!

[Lotus-e-Clan]

What about water pump bearings?
Is your water temperature behaving?

Same for other bearings in the v belts path.

If bearings are failing then they might make increasing noise up to certain revs and then the v belts slip?

[Bagpussawake]

The water temp is acting as it has since I got the car, it sits a little below what I would expect (80-85 deg normally, rising to 85-90 after running hard for a time, drops quickly back to 80-85 again when I ease off). I'll maybe take the belt off and see if I can see how the bearing feels.

The noise is definitely up near the top of the engine, I'd say around the Aux shaft pulley or cam belt tensioner but it's really tricky to tell, it could maybe be the water pump but not either cam shaft, the distributor or the PAS pump, they're too far away.

Any views on spraying WD40 or similar on the Cambelt tensioner?

[bash]

Im not saying that it is this but, when I changed the belt on mine a few years ago the bracket that held the tensioner to the engine had developed a stress crack, to the point that it had only 3 or 4 mm left before it broke off. I was lucky that the belt change coincided with this discovery. Get hold of the tensioner and see if it, or the bracket, wobbles about. If it catches it could be producing a squeel.

Bash

[Lotus-e-Clan]

Those temperatures seem a little high to me, but could be caused by a radiator issue and/or the water pump.

In a healthy system the water temp will sit @ 80 - 82C (a 82C stat is STD for this country) and should NEVER near 90C unless in traffic /stationary ....ie you should normally never see near 90C when pressing-on...up to 84C maybe...

Some of us who have had a high efficiency rad recore will see running temps/cruising temps as low as 78/79C. (esp in cooler months). 88/90C is where he rad fan(s) should kick-in bringing the temp down by 10C to 78/80C.

If in the end you verify that there is nothing wrong with your water cooling system then beware of the possibility that ignition timing problems or high oil temperatures could be causing the higher running temps when pressing-on.

For example, the Mocal style air/oil radiators (std on the Excel) should be thrown away and replaced with new if the engine has ever spun a bearing/there has been an engine blow-up. They are very difficult to flush and can become partially blocked with engine /bearing debris...

[Bagpussawake]

Right, been out again this evening. There is no wailing at all until everything is warmed up, even then when the car drops to idle it sometimes stops.

I'm convinced the noise is coming from the aux housing.

Anywhere I can get service notes for information on how to dismantle (and remantle!) the aux housing/oil.pump assembly? It seems easy enough to remove but I have no info on torque settings and pitfalls for the unwary that may apply for reassembly....

Btw @ Lotus-e-Clan: I took careful note of the engine temps tonight and I overstated them before, the normal running position on mine is actually just below 80, the highest I've seen was actually just under the 85 mark (not 90 as I originally thought). I'm afraid I've never really taken close note of the actual values, just if it stayed steady at its normal position and if traffic or driving caused a rise, that it dropped back quickly when things returned to normal

[alanmoss]

Just a thought, check the power steering pump mountings.

[Bagpussawake]

Progress so far:

Definitely not either V-belt or the PAS pump mounting, alternator bearings, water pump or the cam shafts/pulleys.

Tried WD40 on the cambelt tensioner after speaking to my father-in-law (he's an aircraft engineer working on helicopters) to check that it would do no harm. It made no difference.

Topped the oil up to max (it was midway between max & min) and it seemed marginally better. Before, once it started that was it until you switched the engine off.

The noise never starts until the engine is warm (as before), but now it doesn't appear to start if I just sit idling from cold for a good while (15 minutes), doesn't make the noise if I rev the engine in neutral but does start when I accelerate hard in gear. Stops when I drop to idle again, nothing revving in neutral and then starts again when accelerating in gear.

I've got everything off the front of the engine ready to remove the aux housing and oil pump....

[Bagpussawake]

Stripped the aux housing and oil pump assembly apart and replaced the aux shaft seal.

Noise has now gone.

[irishwolfhound]

same noise happened to me on the way to the raf cosford meet turned out to be the alternator shaft was moving back and fore in the case and the noise was caused by the pulley my local electricians advanced in birkinhead rebuilt it with a new case, apparently its quite a common failure as the front bearings on the shaft arnt held in by a circlip, the rebuilt it with an old case and modified it with a front circlip holding the bearings into the shaft grand total of 24 hours later and £30 so its worth checking just pull and push the pulley and see if the shaft moves back and forewards