Alternator knocking

brorabongo · Post by **brorabongo** » Fri Feb 29, 2008 8:50 pm

I'm hearing a loud knock/tapping noise, which corresponds with the revs, I think I have traced it to the alternator. I sprayed WD40 into the alternator whilst running, and the noise stopped. Does it sound like it could be alternator bearings? if so can they be replaced, or is it a case of replacing the alternator.

Cheers.

Sod's law, it happens within minutes of me booking a hotel for a couple of days, at the end of March.

The Great Pretender · Post by **The Great Pretender** » Sat Mar 01, 2008 12:19 am

Sorry to hear you have a problem and I cant help you on that, but spraying WD 40 into a running alternator is a NO NO you are lucky it didnt go up in flames

dandywarhol · Post by **dandywarhol** » Sat Mar 01, 2008 1:40 am

Only if you spray the back end where the brushes are surely? even then it's unlikely, the alternator fan will blow them out

The Great Pretender · Post by **The Great Pretender** » Sat Mar 01, 2008 1:45 am

dandywarhol wrote:Only if you spray the back end where the brushes are surely? even then it's unlikely, the alternator fan will blow them out

On a serious note it only takes a spark to ignite the vapor. Been there done it.

mister munkey · Post by **mister munkey** » Sat Mar 01, 2008 9:43 am

It sounds very much like its the back bearing giving up the ghost. It happened to me over Christmas.

Hopefully you are still on the original Mazda unit with the 10mm shaft, its fairly straightforward to get that bearing replaced. Get down to an auto electrician before the big bang, It'll save a lot of hassle & expense.

Good luck.

brorabongo · Post by **brorabongo** » Sat Mar 01, 2008 12:54 pm

mister munkey wrote:It sounds very much like its the back bearing giving up the ghost. It happened to me over Christmas.

Hopefully you are still on the original Mazda unit with the 10mm shaft, its fairly straightforward to get that bearing replaced. Get down to an auto electrician before the big bang, It'll save a lot of hassle & expense.

Good luck.

Auto Electrician? in Brora? no chance.

I'll have to check the yellow pages, for the nearest.

Cheers for the replies guys, and I promise not to spray WD40 into it again whilst running.

Veg_Ian · Post by **Veg_Ian** » Sat Mar 01, 2008 5:49 pm

Well in the past I've got by with a dodgy bearing on an aircon pump bearing for 5 years by pouring a bit of engine oil into the bearing (not when running mind) a tad thicker than WD40. It's a stop gap until you get around to changing the bearing.

haydn callow · Post by **haydn callow** » Sat Mar 01, 2008 7:13 pm

Mister Munkey....that is a very impressive photo of your Bongo you use as a avitar.

mister munkey · Post by **mister munkey** » Sun Mar 02, 2008 6:09 pm

haydn callow wrote:Mister Munkey....that is a very impressive photo of your Bongo you use as a avitar.

Many humble thanks Haydn but I can't take the credit for that. Its those clever little Japenese people who built & painted my Bongo that need congratulating on making such a beauty!

brorabongo · Post by **brorabongo** » Wed Mar 19, 2008 11:51 pm

Veg_Ian wrote:Well in the past I've got by with a dodgy bearing on an aircon pump bearing for 5 years by pouring a bit of engine oil into the bearing (not when running mind) a tad thicker than WD40. It's a stop gap until you get around to changing the bearing.

Tried the engine oil method tonight,

Veg_Ian

As still waiting for my new alternator to arrive

Am I right in thinking that you can adjust the tension of the belts, with the long bolt (1), then tighten the side bolt (2) to lock?

brorabongo · Post by **brorabongo** » Tue Apr 08, 2008 11:04 pm

Alternator arrived today, brand new, sealed, and no exchanged all for under £200, and fitted this evening.

Replacing the alternator was straight forward, and it took longer to find the right size spanners, 12mm and 14mm.

plenty of 10mm and 13mm lying about.

The bongo is running quieter now, and I don't know if I imagined it, but the warning lights which come on when you first turn the key seem brighter.

However, I was wanting to replace the belts whilst at it, but I just could not get the tensioner pulley for the air con belt to drop/slacken. I had the long bolt out, and tried to persuade the pulley to drop with a length of wood, a mallet, and plenty of WD40, but after a while I had to give up. I just left the original belts on, for now.

Any ideas how to shift the b****y thing?

Plus has anyone refurbed an alternator before? AFAIK the leccy side is ok, it's just the bearings are getting noisy under tension. It is not that noticable when the pulley is spun by hand.

That was the Radiator (slow leak) replaced last week, and the alternator today, none of them failed totally as such. They were both starting to show their age, and the faults were found early enough to order the replacements before suffering a breakdown. (the bongo, not me)

thats it for a while........a long while!!! I don't know how I'm going to tell the wife and kids "There will be no food on the table for the rest of this month, but at least the bongos going great now."

Post by **Simon Jones** » Thu Apr 10, 2008 8:33 am

I've also put this on the other thread about changing the belts:

There is a large nut (poss 22mm) on the front side of the tensioner pulley. This clamps the pulley bearing to the slotted part. Unless you slacken this off, the long adjusting bolt will have no effect.

When I changed my alternator belts, I couldn't get the new aircon belt on as it was too tight, so ended up using the original

brorabongo · Post by **brorabongo** » Thu Apr 10, 2008 9:49 am

I did try that, it was a 17mm nut on the pulley wheel, but I could not get it to shift. I was trying it from above. I will be taking it to a garage tomorrow, for wheel balance test, as the steering wheel shakes at 65mph, so we are going to try to replace the belts then aswell.

Alternator knocking

Alternator knocking

Re: Alternator knocking

Re: Alternator knocking

Re: Alternator knocking