No exhaust manifold heat shield + power = cooked alternator?

[TwIzTeD_3kGt]

I'm just about replace alternator #2 with alternator #3. Just stopped charging last night. The original alternator lasted 8+ years at BPU power levels, 5 of which were after removing the manifold heat shields. It died last November just before I put the car away for Winter, but after I had the car running well at ~440whp. #2 was pulled from my '93 VR4 as a quick replacement. It lasted from February until last night, again after I had the car running well for a few weeks. Particularly after I went for a drive just to have some fun (so beating on it).

I didn't find any faults in the wiring or grounding, so my only thought is the voltage regulator is just inches away from the exhaust manifold. Maybe it's cooking? I figure under boost that manifold is probably glowing red. The intercooler pipe runs right over the other side of it.

Anyone have this problem? Should I get some stock manifold shields back in there? Or should I buy some heat shielding wrap?

[CoopKill]

I know a few cars with no sheilds without issues. Not to say that is not your issue though. Maybe make a sheild that mounts to the alt mount, and runs between?

[green-lantern]

What turbos? Stock manifolds?

I've never had heat shields and never had an issue other than cooking the insulation a little on the fire wall. Is there some aftermarket electronics in the car? Big stereo or something?

[TwIzTeD_3kGt]

Just 19ts, no big stereo but I do have an aftermarket Sony deck that I recently connected to the stock amp with a Metra cable.

[green-lantern]

Just 19ts, no big stereo but I do have an aftermarket Sony deck that I recently connected to the stock amp with a Metra cable.

Same as me (19t's), did this problem pop up about the time you installed the deck? I actually have a Sony deck hooked to my stock amp also. lol

[Chris@Rvengeperformance]

Get a Denso alternator from amazon, better quality than the parts store ones. I also see no reason to not run the manifold shield. You can get a new one from the dealer for about $25.

[bboyalan]

To the OP: that actually happened to my car's original alternator as the PO ran w/o shields for some time. When I had it rebuilt by a local shop, the inspection notes included obvious signs of failure from heat. Just my two cents!

[TwIzTeD_3kGt]

To the OP: that actually happened to my car's original alternator as the PO ran w/o shields for some time. When I had it rebuilt by a local shop, the inspection notes included obvious signs of failure from heat. Just my two cents!

Sounds like what I want to hear! I'll be dropping the 2 bad alternators off at a local rebuild place to see what they say about the cause of failure. Did you replace or add heat shielding afterwards?

[bboyalan]

Sounds like what I want to hear! I'll be dropping the 2 bad alternators off at a local rebuild place to see what they say about the cause of failure. Did you replace or add heat shielding afterwards?

hehe interestingly, I added back all of the front+rear shields when I did a turbo swap for the PO prior to him selling the car to me. The shields were off for only a few thousand miles, and then I was able to get a few thousand more (DD) out of the alternator until it began to insufficiently charge around sub-140k. It might have been a coincidence due to mileage+age, but the old timer said it was a cinch after his inspection; he knocked out the rebuild so fast for cheap w/ warranty ($95 IIRC).

I put it through some hell with my fresh build afterward! 80-mile daily commutes in San Diego, SoCal 9x.x summer in stop-and-go traffic, MANY 8k pulls, etc etc. She was a charging champ for 10k miles lol. Aside from the shields, I did have switched fans and a GT300 hood.

Hopefully your experience becomes a positive one too! I am interested to hear about the results.

[jras312]

Any more info on this? My alternator isn't charging after my rebuild and I have the heat shields removed. Going to remove it and get it tested later tonight, but if it's bad I don't want to get a new one just to have it cooked again. How is yours holding up OP?