Alternator

[Petemate]

Last couple of weeks a harsh noise has been heard on idle. Stuck my home-made stethoscope (ie a long Snap-on screwdriver with a lump of rag on the handle) against various engine parts, traced to the alternator. So yesterday, off came the aux belt, and I found about 1-2mm up and down and about 5mm in and out at the pulley. Ordered a replacement unit from Eurocarparts, Bosch to replace the bosch unit currently fitted. Initial discount, plus 'end of month' promo, cost down to £195. Plus new aux belt (well, I planned to replace it in about a month when I service the car) similarly discounted to a tenner.

Just got the old unit off in about an hour and a half. Worst bit was releasing the dratted large loom clips for which I had to remove the air box to get at the tage from beneath with pong-nosed-liars.

Spun it with my drill with a rubber wheel and the unit is rattling like a good 'un. Would have had the job finished today but OH needed the car for lunch with friends, so couldn't start it until the engine had cooled down. I reckon the new one should go in a darned sight faster than the old one came out.

Slightly O/T, good result from my recent blanking off of the EGR; at the same time I rermoved, stripped and cleaned the intake manifold with the assistance of my lad's vapour blaster. What a difference that has made; 3-4 better mpg running around, 4-5 better mpg on runs, and 3-4 mpg towing. Plus the benefit of the car now going like a scalded cat.

[sgould]

WHat's the mileage on that alternator?  I thought it was only the Denso ones that failed prematurely.

[mikeloadsasaabs]

A failing alternator was the straw that broke the camel's back, and made us decide to get rid of our faithful 9-5 Aero estate. It cost half the value of the car to replace at €650 parts and labour. It failed at about about 230,000 miles - they don't make anything to last do they  . The car was a 2004 model, no idea whether it was a Bosch or Denso.

Petemate, I'm impressed that you changed it yourself. The mechanic that replaced it for us said it was a real b*gger of a job! He only quoted, and charged, for around an hour's labour but he said it took him a lot longer.

[Audax]

WHat's the mileage on that alternator?  I thought it was only the Denso ones that failed prematurely.

The only ones fitted to the early cars (05-07) were Denso and they were rubbish, maybe they switched to use Denso and Bosch later on because of reliability but it's possible that Bosch units on the 9-3 are not as good as the Bosch units fitted to the 9-5. 

[Petemate]

WHat's the mileage on that alternator?  I thought it was only the Denso ones that failed prematurely.

Just over 100k Audax. I have just, for curiosity, clamped it in the vice and used my drill with a rubber covered flapwheel to spin it up and the awful chattering noise which I could hear with it in the car was immediately obvious. I had also given the tensioner pulley and the idler pulley a good check and they are both OK. For the record, the charging was not showing as high as I would have liked when I checked it a couple of months ago. I know it is a Bosch unit, but the bearing is well shot. Even if it could have been replaced, time is against me as we need the car back on the road asap, and even though the Bosch units are said to be more reliable, with that mileage I would not be confident with just a bearing replacement. The new one will be on by lunch tomorrow, as I'm collecting it straight after brekkie.

[Petemate]

Petemate, I'm impressed that you changed it yourself. The mechanic that replaced it for us said it was a real b*gger of a job! He only quoted, and charged, for around an hour's labour but he said it took him a lot longer.

Thanks for the kind comment. The worst part of the removal was getting the main wiring looms out of the way; I had to remove the air filter box to get some long nosed pliers under the fittings to squeeze them to release them. Also (a tip from one of the Vauxhall forums) I undid the electrical connections after removing the alternator and tipping it over on one side. Refitting the new one should be easier.

[collywobble]

The alternator went on our 9-5 2.2 TiD at around 172,000 miles - replaced with a new Bosch from Euro Car Parts which cost £124.92 exchange which I thought was a good price.  My garage charged me about £70 to fit it so not too bad apart from him telling me that the crankshaft pulley was deteriorating!  That lasted another 3000 miles and the new one cost more than the alternator!

[Petemate]

Well, in the event, I didn't start to refit the new alternator until after 1pm. Finished just in time for afternoon tea at 3pm. The worst part of the job was getting the small connector to fit. The mini spade terminals were the right size, and the right spacing, but the connector would not push on to the block. Found on examination that the flutes on the the connector were slightly different to them in the receptacle on the alternator. Ended up trimming a couple of them off with a small hobby knife. Very tricky to do leaning over the engine compartment but OK in the end. There must be very small differences in manufacture from factory to factory. After a few years at BL in Cowley, Oxford, I know how these things can happen lol. The main looms alongside the air fiter box had to have the tie wrap treatment to secure them again. While I had the car to bits yesterday I ordered some new plastic nuts for the wheel arch liner - these came today, so result.

One tip on one of the Vaushall forums was to reconnect the electrics on the alternator before installing it. I didn't do this as I didn't want to put the cables under strain, especially the small one. So I put the lower bolt in loosely, then put the top one in and nipped it up, then  removed the lower bolt again and swung the alternator back out pivoting it on the upper bolt. Did it like this due to the weight of the unit. Then I was able to fit and tighten the main connector. The small one I have covered earlier in this post.

Quite pleased with the result.

[Petemate]

The problem connector was something like this. When I lined the two alternators up on the counter they both appeared identical; even the fittings for that small plug on the units looked the same. A magnifying glass would have picked up the differences in the flutes but hey, I didn't see them that closely. Doh.