91 L300 Start Squeak

tomaboyd · Post by **tomaboyd** » Sat Nov 12, 2016 8:18 am

1991 Delica L300, 130,000 KM. Well maintained.

I have a high pitched squeak coming from the engine bay on start up.

This goes away at rpm's > 1,200 or so and goes away completely when the engine is warmed up. Goes away completely if the car is driven regularly. I am bike based and so only go out in the Delica 2 or 3x per month.

I assume this may be the bearings in something (alternator, water pump).

What is the most likely candidate and how do I check it?

Thanks.

204explorer · Post by **204explorer** » Sat Nov 12, 2016 9:52 am

So your sure it's not a belt? If you rule out the belt then I would remove the belt and spin all the pulleys by hand, see if one feels rough.

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Post by **Growlerbearnz** » Tue Nov 15, 2016 1:54 pm

Try starting the engine and, while it's squeaking, turning on your headlamps to bright. If the squeaking changes it's slipping alternator belts.

tomaboyd · Post by **tomaboyd** » Thu Nov 17, 2016 9:19 am

I will check the belts, but pretty sure that is not the problem. They are in good shape and, having worked on cars for 30+ years, I am pretty certain on what a loose belt sounds like.

Plus, the noise does not go up or down with increased/decreased rpms. That is usually a good belt indicator. The sound just goes away about 1500+ rpm.

If it is not the belt, what is the most likely problem? What would most likely fail first, water pump, alternator, turbo?

Post by **Growlerbearnz** » Thu Nov 17, 2016 6:24 pm

Any chance you could record the engine making the noise?

If it's not the belts I'd check the crank pulley- the rubber damper material can split, letting the outer part rotate independently of the inner part. If the pulley looks like it's wobbling as the engine runs then it's bad.

Next I'd check out all the drive belt bearings. I'd look at the water pump bearing first. If someone's overtightened the belts to try and make the noise go away the water pump bearing suffers, though I would expect the pump to start leaking before the bearing started making noise. Then I'd look at the alternator bearings, aircon belt idler pulley, and timing belt tensioners (because you don't want them to fail).

I wouldn't expect the turbo to make any significant noise at low revs.

That said, worn alternator belts (and sometimes even new ones) make a repetitive chirping noise, worse if the engine has to use the glow plugs to start, which goes away over 1500rpm and/or when the engine is warm (once the battery is charged). You can see why I think you're describing belt squeak

. Belts should be replaced in matched pairs, and tensioned to a deflection of 10-14mm at 10kg force, measured on the longest run.

philmeup1 · Post by **philmeup1** » Thu Dec 01, 2016 8:12 am

I'm having the exact same issue with my Delica. I had the belts tightened last spring as they were loose. But now it's sounding exactly as you've described above when idling. Please post when you isolate the problem.

Good luck, Cheers

tomaboyd · Post by **tomaboyd** » Sat Dec 03, 2016 7:41 pm

Roger that.

I did adjust my belts today. On the tight side and the noise did go away.

When I had the belts and pulleys off I spun the alternator and power steering pump and they felt fine. I have removed the AC belt so that can't be the issue.

204explorer · Post by **204explorer** » Sat Dec 03, 2016 8:34 pm

Sometimes the pulleys wear out. The belt sits on the bottom of the pulleys and is not wedged on the flanges of the pulley. It's hard to tell unless you install a new pulley. This applies to regular v belts. It happens less with serpentine belts.

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Post by **Growlerbearnz** » Mon Dec 05, 2016 3:56 am

I've just had another look at my own belts, and I might have figured out why they always squeak:

http://www.delica.ca/forum/viewtopic.php?f=6&t=17994

204explorer · Post by **204explorer** » Mon Dec 05, 2016 6:12 am

I just read your post growlerbearnz. I think belts that ride on the bottom of pulleys is often the issue for noisy belts. Most people don't believe that a belt can wear out a pulley. And like you posted, not all belts are created equal.

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Post by **Growlerbearnz** » Mon Dec 05, 2016 3:02 pm

204explorer wrote:I just read your post growlerbearnz. I think belts that ride on the bottom of pulleys is often the issue for noisy belts. Most people don't believe that a belt can wear out a pulley. And like you posted, not all belts are created equal.

That's made me wonder if my water pump pulley has worn to suit the original style belts, and that's what's causing the unusual wear pattern on the deeper aftermarket belts. My alternator and crank pulleys are new, but the water pump pulley has 260,000km on it.

apatnode · Post by **apatnode** » Wed Dec 28, 2016 2:40 pm

Was having a similar problem with my 1992 L300. Turned out the harmonic balancer (crankshaft pulley) was on its way out. Might want to check that out as it can lead to catastrophic engine failure...