Noisy alternator?

dogbower · Post by **dogbower** » Mon Jun 02, 2008 8:24 pm

Hi
my car has recently developed a nasty sounding noise from the engine. It doesnt seem to be there when it is first started but once heated up I get a knocking noise at idle up to about 3000 rpm, above this I cant hear it, but this may be down to the increase in overall noise.
I hope

that it may be the bearings in the alternator so after consulting my haynes I decided to remove belt and see if noise goes.
haynes indicates you need a peg spanner to remove the pulley/belt, as I dont know what one is thought I would just stick a screwdriver in, one chipped fan blade later

I think its best to do this right.
First question is what a peg spanner and where do you stick it?
Second is anything else you lot think it may be?
I have limited skills but can follow clear instructions so please give instructions aimed at a simpleton.
Thanks Stuart.

impmad2000 · Post by **impmad2000** » Tue Jun 03, 2008 7:57 am

A peg spanner locates into two of the ring of holes in the fan, around the centre nut. It will allow you to hold the fan still whilst undoing the big nut.

This could be alternator bearings, get the engine warm, then pop the fan belt off, and try it again, for a short time only, you don't want to overheat it !!
You'll soon know wether the noise is still there.

It could also be the famous cam chain tensioners. Failure of these on my motor gave very familiar noises. Sounded like a waterpump failure, and I knew it wasn't that !!
Good luck
Tim

58A - 71E · Post by **58A - 71E** » Tue Jun 03, 2008 10:59 am

Here's the one I got from pelican

http://www.pelicanparts.com/catalog/sho ... LS_pg5.htm

Mine was a similar story to Tim's

dogbower · Post by **dogbower** » Wed Jun 04, 2008 10:04 pm

Thanks for the replies, as I didnt have the tool to look at the alternator I thought I might as well have a look at the tensioners.
I wanted to respray my exhaust anyway and one bit of tinware later I could get at the covers.
offside first

then nearside

Thought things looked alright and decided that my first thought of alternator must have been correct, also wondered what the red modern looking bits were.
Then noticed that the chain on nearside was slack at the bottom of its travel.

Came onto DDK to read all the bits on chain tensioners and discovered that the red bits were a collar to save the engine if tensioners fail. Looks like they work then.

Think I will go with origionals and keep the collars.
Dont really want to remove the engine do I have to?
Have read most of the threads on tensioners but any other advice or hints.
Best place for parts and any other things to do while covers are off?
Is it woth replacing both even though offside looks fine.
Replace or repair?
Thanks Stuart.

impmad2000 · Post by **impmad2000** » Thu Jun 05, 2008 7:25 am

Yes, the NS cam tensioner looks to have collapsed. The collar is sat flush with the top of the tensioner. Collars - They work !!
I believe that is an early style tensioner, not repairable (or not adviseable, not sure which). The easiest approach is to replace the tensioners with the later 930 tensioners, or pressure fed tensioners. There seems to be little in it as far as which to choose. If its new 930 tensioners, don't forget to bleed them before fitting.
Change the chain ramps whilst there.
Pop the engine out, it will be worth the efffort as it isn't actually that hard to do. You could probably get away without, but I suspect you'd be making the job harder.
Good luck.
Tim

hot66 · Post by **hot66** » Fri Jun 06, 2008 7:48 pm

Hi Stuart

Might be best to edit the title of this thread to ... chain tensioners - HELP !

Personally I think you should stick with mechanical tensioners & re fit the safety collars as they obviously work & have saved you a potentially huge bill .

These collars can't be fitted to the hydraulic tensioners & these have been known to fail + if you have a sudden drop in oil pressure ( eg the oil lines fail or an oil pressure drop due to other engine problems) these will fail too.

Mike Bainbridge has explained to me many times & shown me all the different tensioners, but I'm hopeless & can't remember a thing so can't advise on wether your tensioners are suitable to be rebuilt & bled or wether it is better to fit new ones ( which should be re - bled anyway before fitting.

Might be worth giving Mike a call & discussing things through with him ( just mention you are DDK

)

58A - 71E · Post by **58A - 71E** » Sat Jun 07, 2008 10:34 am

Stuart, if you replace with the latest 930 types and keep your original idler pulleys you will also need a spacer washer
see this thread
http://www.ddk-online.com/phpBB2/viewtopic.php?t=9143
personally I replaced with the later style (bushed) ones; see this one
http://www.ddk-online.com/phpBB2/viewtopic.php?t=10173

Cheers