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Alternator bracket help (pics?)


jcb1100
06-20-2009, 07:23 PM
Hello to all,

I am just completing a UIM and LIM job on my '97 Grand Prix 3800 (NA) with about 120,000 miles--thanks to all the previous posters on this topic! This forum is extremely helpful, and I wouldn't have attempted the job without all the help I've gotten here. I thought I could get through without posting a question, but no such luck.

I'm 95% finished, and wrapping things up, and putting the alternator back on. It's such a simple part of the job that I didn't really take note of where the bracket bolts to. I know that one end goes on the end of the long bolt which goes through the bottom of the alternator, with a nut on top of the bracket. The other end is confusing me. I know the bracket runs about parallel to the installed belt, and attaches somewhere below the coil pack. I just can't get that end to work.

Can someone explain, or post pics of, the other end of the bracket, under the coil pack? That end of the alternator bracket has a short spacer or tube built in, and I can't get the bolt that goes into the hole in the iron piece attached to the engine to thread after it passes through the bracket. I can't figure out if I mixed up the bolts, or I'm completely confused.

Thanks for any help you might provide. I feel stupid even asking, but I'm baffled.

tblake
06-20-2009, 09:11 PM
On the 3800... (If my memory serves me correctly)

the alternator belt tensioner assembly which has 3 15mm bolts all the same length.

then the alternator should just flop right into that. there is one long bolt that goes through the alternator almost as a pivot bolt. It runs parallel to the firwall.

Then there are two more bolts for the alternator. One is a bolt with a stud on top. It gets inserted downwards towards the back of the alternator near the forwall, furthest towards the outside. Then the other alternator bolt also goes downwards right next to the first one.

Then the bracket (tubular 1 inch thick one). If we are thinking about the same one, one side hooks onto the stud sticking up on top of the alternator, and the otherside gets bolted to the back of the supercharger (not the coil packs).

Then your little EVAP solonoid gets bolted to the top of this bracket.

tblake
06-20-2009, 09:16 PM
Opps, 3800NA not 3800SC, I think they might be slightly different. I'm not for sure though.

Its been a while since I've worked on a 3800NA, I cant remember.:rolleyes:

jcb1100
06-21-2009, 05:20 AM
Thanks for the reply, but yes, I think your first response was for the SC, and I have found lots of pics for that. My bracket (brace?) is a straight piece maybe 7 inches long, generally flat, but with a slight c-shape in profile, with a hole on one end and a "thick hole" or built-in spacer at the hole at the other end (sorry for the poor wording). The flat hole mounts on the long bolt at the 6 o'clock position on the alternator (the bottom). Facing the passenger side of the car, the brace runs down at about a 4 o'clock angle to a point just below the coil pack.

There are three studs coming out of the block on that side, but the brace is only long enough to reach two. One has a 15 mm bolt with a ground wire, and the other has a 13 mm bolt, which sits inside a round cast "hole". This stud has threads above and below the nut. I think the brace goes to this stud, but if I put the stud through the brace, it's not long enough for the threads to catch in the block, and if I put the brace on the outer portion after threading it in, the hex portion won't fit inside the tube of the brace.

Maybe I'll try to post pics of what I have.

Thanks again.

Jim

BNaylor
06-21-2009, 09:12 AM
On the 3800... (If my memory serves me correctly)

the alternator belt tensioner assembly which has 3 15mm bolts all the same length.

then the alternator should just flop right into that. there is one long bolt that goes through the alternator almost as a pivot bolt. It runs parallel to the firwall.

Then there are two more bolts for the alternator. One is a bolt with a stud on top. It gets inserted downwards towards the back of the alternator near the forwall, furthest towards the outside. Then the other alternator bolt also goes downwards right next to the first one.

Then the bracket (tubular 1 inch thick one). If we are thinking about the same one, one side hooks onto the stud sticking up on top of the alternator, and the otherside gets bolted to the back of the supercharger (not the coil packs).



Tim, for '99 and up with or without SC your procedure is correct. However, the '97 and '98 models with NA or SC 3800 have different alternator mounting hardware starting with the bracket that goes back to the area of the engine underneath the coils packs. The revision is much better.

tblake
06-21-2009, 09:21 AM
Thanks for clarifying Bob!

Interesting prediciment Jim. These type of things are usually so simple that when you figure it out you feel like an idiot.

jcb1100
06-21-2009, 03:31 PM
Yes, I anticipate feeling like an idiot when I see what I'm missing. :-)
I think I just need to see a picture of one with the brace in place, so I can put two and two together.

BNaylor
06-21-2009, 06:32 PM
Here is a pic from my collection that may help. For '97-'98 vintage L36 SII 3800 engine. Make sure you properly connect the ground wire to that bottom bolt since that is the ICM ground.

http://i5.photobucket.com/albums/y186/lizzywiz/L36_alternator.jpg

jcb1100
06-21-2009, 07:04 PM
That's exactly what I was looking for. Thanks--this forum and its members are the best! Now I just have to figure out why my threads aren't catching.

Jim

dozer1
06-21-2009, 07:26 PM
try leaving all bolts loose till they all catch

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