View Poll Results: How many braces for the AC Bracket do YOU have?
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How Many Braces on your AC Bracket? 91 L98 engine
Thread Starter
Team Owner
Joined: Jul 2004
Posts: 28,485
Likes: 3,291
From: Hartford WI
How Many Braces on your AC Bracket? 91 L98 engine
Like the question goes, how many? The pic shows 3. Some brackets have only 2 (water pump to bracket and back of compressor to exhaust manifold stud). Some have a 3rd one from the bracket to the fuel pump blockoff plate stud like the pics below.
Most people say they have #5 and #9. Some say they have #6.
TIA
Most people say they have #5 and #9. Some say they have #6.
TIA
Safety Car
Joined: Aug 2009
Posts: 3,752
Likes: 276
From: Melbourne, Victoria, Australia
I now have all 3 braces on my 85 with the 88-91 a/c and bracket.
I made the no.6 brace on the weekend, when i replaced my water pump. (seems the No.6 bracket is rare as rocking horse ****)
oxy cut a ''boomerang shape bracket'' out of 1/4 inch steel so it does not interfere with the lower radiator hose.
See pics below first pic is brace no.5 second no.6, looks like the 90-91 a/c brackets had the no.6 bracket boss and hole.
I still think alignment between water pump and head is the key issue,
where my old pump had the heater hose return pipe contact the bracket before the bracket sat on the water pump bolts!!!.
The new water pump has everything as it should be, i put the bracket on with bolts finger tight and there is no play at all.
Note the 85 head needed a hole drilled and tapped in the head, with a 1/4 inch washer to fit between head the later a/c and bracket.
(the 84-87 a/c compressors had issues, i went thru 3 early a/c compressors before i saw the light. Oh and 1x broken 88-91 a/c flimsy bracket issue.
My current bracket has been on the engine for more than 7 years though and still going strong.
I made the no.6 brace on the weekend, when i replaced my water pump. (seems the No.6 bracket is rare as rocking horse ****)
oxy cut a ''boomerang shape bracket'' out of 1/4 inch steel so it does not interfere with the lower radiator hose.
See pics below first pic is brace no.5 second no.6, looks like the 90-91 a/c brackets had the no.6 bracket boss and hole.
I still think alignment between water pump and head is the key issue,
where my old pump had the heater hose return pipe contact the bracket before the bracket sat on the water pump bolts!!!.
The new water pump has everything as it should be, i put the bracket on with bolts finger tight and there is no play at all.
Note the 85 head needed a hole drilled and tapped in the head, with a 1/4 inch washer to fit between head the later a/c and bracket.
(the 84-87 a/c compressors had issues, i went thru 3 early a/c compressors before i saw the light. Oh and 1x broken 88-91 a/c flimsy bracket issue.
My current bracket has been on the engine for more than 7 years though and still going strong.
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Racer
Joined: Sep 2007
Posts: 375
Likes: 18
From: Lawrenceville Georgia
Racer
Joined: Sep 2007
Posts: 375
Likes: 18
From: Lawrenceville Georgia
The purpose of the frisbee is to dampen the shock of the AC Compressor cut-on. I've just noticed several people have the same problems, have also read where others have removed frisbee and no problems. I chose to leave mine.
Joel
Joel
Thread Starter
Team Owner
Joined: Jul 2004
Posts: 28,485
Likes: 3,291
From: Hartford WI
That is the item on the water pump, right? Could that be the issue? Or could the AC compressor be faulty where it shocks too much?
Racer
Joined: Sep 2007
Posts: 375
Likes: 18
From: Lawrenceville Georgia
I really have no hard evidence of frisbee removal causing this type of damage to the brace. But, it was installed by GM for a specific reason. And I have read several articles regarding this, and the purpose was to dampen the shock.
And yes, that's it hanging on the end of the water pump.
Now I'm sure there will be some folks jump on this as being just a hunk of heavy metal doing no good. It's there for a purpose.
Joel
And yes, that's it hanging on the end of the water pump.
Now I'm sure there will be some folks jump on this as being just a hunk of heavy metal doing no good. It's there for a purpose.
Joel
Le Mans Master
Joined: Oct 2008
Posts: 9,758
Likes: 49
From: Houston Texas
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 13
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 413
From: WV
My 89 is the same, there's just the one bracket from the manifold to the back of the A.C compressor.I've been running it for 6 years this way with no problems. By the way, if yours isn't connected, you will eventually break the aluminum bracket if you use your A/C very often..If you don't use your A/C , the bracket may hold up without any problems. The difference is the extra pressure exerted on the bracket when the A/C is running.If the A/C isn't running there is very little pressure because the pulley is turning freely......WW
Last edited by WW7; Jan 17, 2013 at 08:39 AM.
Pro
Joined: Oct 2008
Posts: 706
Likes: 265
From: Jyväskylä, FINLAND
Yes, several years and tens of thousands miles before the failure. As I stated before, the most liable reason for that shredding was because one of the bolts was detached due to thread failure.
Last edited by Yorcci; Jan 17, 2013 at 08:38 AM.
Pro
Joined: Oct 2008
Posts: 706
Likes: 265
From: Jyväskylä, FINLAND