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MikeJinCO · Posted: Mon Apr 06, 2020 9:39 am Post subject: Alternator Mounting

This question is oriented toward 924RACR and 50plus. For my track only car. I just spent 2.5 hours getting the alternator off. There is no room between the header and the cooling tube cover to get to the back nut on the upper pivot bolt. The -10 hoses from the remote oil filter adapter don't help much either. I managed to get it off, but reassembly is out of the question.

Do you leave off the cover and just get a tube to blow air over it, or do you modify the bracket that bolts to the block so that I can drop a nut thru and hold it with a wrench? One other possibility is that with my solid bushings I could just weld the nut to the bracket.

My driver school and first race in May have both been canceled to I've got a month and a half to get this one figured out. Our next scheduled race is about June 13 and I think odds are 50/50 on that one.
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Mike

'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

924RACR · Posted: Mon Apr 06, 2020 11:24 pm Post subject:

Yeah, it's a pain.

The biggest improvement I made on this area was to put a Weatherpak quick-disconnect on the two wires to the alternator, instead of them being bolted to the back of it. Though my ground strap is still bolted on, could improve that yet.

Welding (or even brazing) on the nut to the backside of the solid bushing would be a great improvement, maybe I'll do that next time I'm bored. But I've been able to sneak in there to date and get the washer and nut on without too much issue. But I do have small hands.

I should note I also added in a Weatherpak quick-disconnect for the starter leads, even more useful there for starter swaps, given the damn thing's so heavy. Though now I have a starter relay up top, so don't even need the smaller connector, just the main large gauge cable.

So yes, I do still run the cooling shroud, I wouldn't consider running without it due to the heat issues.

So tacking in the nut is probably the ideal answer for you.
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

MikeJinCO · Posted: Tue Apr 07, 2020 2:52 am Post subject:

The voltage regulator appears to be fried as it jumped from 14+ volts to closer to 16. I had pretty much decided that the fixed rear nut is the way to go, all the newer cars and trucks I've looked at have fixed mounts like that, none of this rubber bushing stuff. Since all our races are sprints of not more than 20 minutes, many folks don't even bother with an alternator, just recharge between sessions. I use an Anderson connector (2 #12 wires)on power leads and the weatherpak on the ground and that helps a lot. If the street car alternator has to come out, it will gets the same.
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Mike

'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

Fifty50Plus · Posted: Tue Apr 07, 2020 3:50 am Post subject:

Unlike Vaughan I don't run the cooling shroud but wrapped the headers with the glass header wrap near the starter motor and solenoid. Tightening the alternator hardware is doable that way. Downside is that I've already cooked a starter motor this past year. Plenty of time to do it over but never enough time to do it right.

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1979 924 NA race car
1982 924 NA race car - Sold
1982 924 Turbo almost a PoS
1981 924 Turbo a real PoS, new engine
1982 924 Turbo nice body, blown engine
1972 911 E race car - going to Vintage
Various 944s to become IT-S race car

MikeJinCO · Posted: Sat Apr 18, 2020 1:19 am Post subject:

Two improvements to the alternator situation. First, I had some left over aluminum heat reflector foil that I had put on the firewall after removing the insulation. I put that on the rear air cover and top of the alternator. It may only reduce the temperature 5 degrees, but anything helps. I don't have heat wrap on the headers. Secondly I made a nut plate out of a chunk of 3/8 bar and two 8mm nuts, first try with a single nut I warped the nut too much with welding heat. I then inserted one of my aluminum bushings and bolted the bracket with some adhesive. I used 3M 2216 a good structural adhesive. I'll use blue Locktite on the bolt and it it breaks loose it will jam against the bracket. On a street car with a bit bigger plate than I used it could be glued to the washer over the rubber bushing with some silicone glue.
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Mike

'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

MikeJinCO · Posted: Mon Apr 27, 2020 10:37 am Post subject:

Well, the jam bracket/mut didn't work. I found that if you pivot the alternator all the way toward the fenderwell it is pretty easy to get into. Unfortunately my new Bosch voltage regulator must be bad as when I connected it to the battery it was a direct short to ground.
_________________
Mike

'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)