Bummer, Check your fan housings!

[masraum]

Well, took the alt out today in preparation for getting a new voltage regulator tomorrow. I knew the fan wasn't perfect (one of those is showing up tomorrow too), and I knew the housing wasn't perfect, but I had no idea how bad it was.
Three of the four blades that mount the alternator support ring to the outer housing are cracked quite seriously. It's not as obvious because the flash lightened the shadows of the cracks, but they go all of the way through either the blade or the alt support ring or a little of both. Needless to say tomorrow someone somewhere is going to be getting my order for a new housing at about $400-$450. OUCH!

My theory is that when the PO had a new alt put in back in '96 the bearings had gone bad causing a bunch of vibration causing the cracks, but since all of the dismantlers that I called said they never have those because they are always cracked... I think eventually age and heat contribute to metal fatigue.

Hope you all have better luck than I did.

[Chuck Moreland]

Can it be repaired?

Surely there is some process for welding magnesium.

[Fishcop]

Bummer!

No point trying to have it repaired?

[masraum]

I have heard some people here mention welding it, and I think it can be done, but most welders won't touch it because Mg will burn if it gets too hot, so it is a safety issue. Besides that this looks like welding would just result in something that was sound at the weld and prone to failure everyplace else.

I think the best thing is definitely replacement with a new part.

This Mg stuff is bizarre. When it starts to fall apart it inflates, for lack of a better word. the ends of a couple of the blades that rubbed at some point in the past are thick and feel as if they've blistered, and the crack in the first picture looks as if something is ready to erupt from the surface of the metal.
Very weird stuff indeed.

[TurboRuf]

masraum

I had the same problem with mine, it's a very common problem. A follow Pelicanite fixed me up with a nice used housing… saved me a bundle.

[addictionMS]

magnesium can be welded but it is very expensive, you need to put the piece into an enclosed space. flood that space with an inert gas and weld inside there. The cost would easily exceed the price of a new housing. I once had to have a part on a sailboat fixed, it was no longer inproduction and was a limited run to start out wiht. SO I paid for this kind of welding, and the only place that could do it was a Mil/Aero fab shop, if you think a P-Car shop cost alot check out a Mil/Aero shop....


Jim

[Roy M]

Sorry if I've got this wrong but isn't the housing itself alloy? - the fan is magnesium but certainly on my 3.2 the housing is alloy. If so then it would be a relatively simple weld.

[Rot 911]

Yes the housing is an alloy that can be welded fairly inexpensively. Several people on this board have had their's welded. I ran into the same problem a couple of months ago. A search will show those postings.

[Rick Lee]

Those fan housings run about $500 from a dealer, but they can be had used for far less - like $50-$150. I needed one for my new engine and was sent two wrong ones and two cracked ones before I found a good and correct one. You need to make sure that the next fan housing you get is exactly the right one. Carrera housings are different from earlier ones. Write down the casting number on the top and start looking. Don't take one that doesn't match exactly. My engine swap lasted 3 wks. longer than it should have because of my having to keep rounding up another fan housing.

[twin plugged targa]

had same problem on my 86.
FYI- was having work done at Vertex of Miami and they had a ton of used ones!.
From memory they sold me one for about + /-$200.
Hope this helps
Ben

[Hetmann]

I have a spare housing, fan and pulley from a 930. The fan is 226mm.
PM me if it will fit your application.

[masraum]

One note, my fan arrived today from Pelican. Fans come from the factory clear coated. So anyone who thought clear coating was a good idea... the factory seems to agree with you.

I have another housing on the way.

[RickM]

Ebay has one now at $25 with alt and fan....Needs a bit of cleaning. An inquiry may determine if it fits your needs.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2402086071&category=33573

[Rick Lee]

After the experience I had, I would require a digital photo of the casting number. Everyone who sent me a wrong fan housing said it would fit my car.

[masraum]

Thanks, but I decided to go with new.

Pricey, but I know it'll be fine for a long time.