Author Topic: Long story and A/c comp, power steering pump, and alternator brackets  (Read 11905 times)

Offline Mark16B

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I'm fixing up this 87 Silverado that was gifted to me from my father who bought it from his father. This vehicle has a lot of sentimental value to me because my grandfather had repaired it some odd years ago. My father and grandfather have always loved vehicles and repaired them since they where young . They have passed this love down to me, with me being 16 I'm determined to have this truck ready for my graduation in 1-1/2 years. I've done most of the work on this truck by myself with a few buddies helping me on the way. I've learned a lot so far but still hit bumps in the road. I've had a fuel problem that had to have a professional mechanic to fix and was done wrong a few times as well. A few years ago my dogs got under the truck and chewed up some wires and the TBI engine has never ran right since so a parts truck with a new 350 was given to me by my father in exchange for some labor around his shop, I found a guy who would swap the motor for exchange of the parts truck and the bad engine. I ended up doing all the work myself, I think the only thing he did was hook the torque converter up to the flywheel. He still however had no problem taking his payment. I recently bought a parts truck for one part in particular, a step side bed that I've been looking for for years. I've finally got it running even though the timing is off I have run into some issues the AC comp, the power steering pump and the alternator do not sit right so the serpentine belt does not sit strait. Here are a few photos with the AC comp off  here's a few pictures of some brackets I have that I'm not sure where they bolt up i have the Haynes repair book but haven't been able to find information on these brackets. If anyone of y'all see any errors in the way I have them booted up please tell me and if you have blueprints that would help as well. Thank you for reading my post and taking the time to help - Mark


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Offline bd

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Re: Long story and A/c comp, power steering pump, and alternator brackets
« Reply #1 on: December 21, 2016, 06:47:59 pm »
...I have run into some issues the AC comp, the power steering pump and the alternator do not sit right so the serpentine belt does not sit strait.

Belt alignment is a common problem.


Figure 1 - The upper A/C compressor bracket fits above the power steering pump and fastens to the front of the cylinder head with the rear A/C compressor bracket sandwiched behind it.  The bracket-to-cylinder head retaining bolt threads into the head through the upper inner bolt hole just below the corner of the valve cover (the hole missing a bolt in Fig. 3, below).  Reinstalling that bracket as described will shim the P/S pump forward ~3/16" and go a long way toward correcting the belt misalignment.  If alignment continues to be a problem peruse the thread, A/C Compressor Replacement and Pulley Alignment.



Figure 2 - This looks like the rear P/S pump adjusting bracket for an application that does not have A/C.  Essentially, it is the lower half of the bracket already installed and fastened to the forward two exhaust manifold bolts (Fig. 3).



Figure 3


Edit: clarity
« Last Edit: December 21, 2016, 08:19:43 pm by bd »
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Mark16B

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Re: Long story and A/c comp, power steering pump, and alternator brackets
« Reply #2 on: December 21, 2016, 06:51:00 pm »
Thank you


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Offline bd

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Re: Long story and A/c comp, power steering pump, and alternator brackets
« Reply #3 on: December 21, 2016, 07:36:05 pm »
I'll add that you are missing the supplemental support bracket/lifting eye (image) that stabilizes the upper A/C compressor bracket by anchoring it solidly to the two, left front intake manifold bolts.  Judging from the absence of a bolt witness mark on the upper A/C bracket in your image, the supplemental anchor has been missing for quite some time.



Due to a nuisance design flaw, an A/C belt standing wave vibration that results from pulley spacing and the compression pulse frequency of the compressor demands that all the factory brackets be installed and tight.  Otherwise, the low RPM vibration is truly annoying.

Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline 75gmck25

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Re: Long story and A/c comp, power steering pump, and alternator brackets
« Reply #4 on: December 23, 2016, 10:59:51 am »
Your belt setup looks like what I have on my '75 with the A6 compressor.

If this is an A6, the bracket is not the lifting eye.   There is an A6  top bracket that bolts to the two bolt holes on the intake manifold that are tucked under the driver's side of the carburetor.  The bracket is shaped in an arc and it extends over the passenger side valve cover and attaches to a 2nd support bracket that fits under it.  The end of the A6 is then bolted to the bracket over the valve cover, and the other other end of the A6 bolts to the brackets you already have.

First picture is the top part of rear bracket, which goes across the valve cover.

The second picture is the bottom part of rear bracket, which bolts to the exhaust manifold.

Bruce
« Last Edit: December 23, 2016, 11:02:04 am by 75gmck25 »

Offline bd

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Re: Long story and A/c comp, power steering pump, and alternator brackets
« Reply #5 on: December 23, 2016, 11:43:29 am »
The 1987 light duty truck models were factory configured for the R4 compressor.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Mark16B

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Re: Long story and A/c comp, power steering pump, and alternator brackets
« Reply #6 on: December 23, 2016, 07:50:29 pm »
I do have the R4 on my truck, I've gotten a supplemental support bracket and installed it, I have not installed the compressor yet because I reviewed some photos I found on different forums and see that I'm missing two spacers that fit between the exhaust manifold and the bracket. Once I install this it should fix my alignment problem. Thank you - Mark16B


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Offline bd

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Re: Long story and A/c comp, power steering pump, and alternator brackets
« Reply #7 on: December 23, 2016, 10:39:46 pm »
Item #18 in the illustration is the double pivot stud for the P/S pump, measuring 3/8" x 16 TPI x 13/16" x 13/16"; the hex at the center of the double stud is ~7/16" thick.  The double stud passes through bracket #21 into the cylinder head.  The P/S pump pivot then slides onto the opposite end of the double stud and secures with a nut and lock washer.  The point you need to understand is that the hex at the center of the double stud not only is used to tighten the stud into the cylinder head and anchor bracket #21, but also "spaces" the P/S pump pivot forward by the thickness of the hex (~7/16").  If you cannot find the correct double stud, you will need to use a longer bolt and substitute ~7/16" spacer between the P/S pump pivot and bracket #21.  Otherwise, the P/S pump and A/C belts won't correctly align.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Engineer

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Re: Long story and A/c comp, power steering pump, and alternator brackets
« Reply #8 on: December 24, 2016, 07:44:25 am »
If you want a little more headache right now but save yourself a ton of headaches later on.....find a complete serpentine belt assembly off of a 1988+ C/K truck with the 4.3L/305/350, or S-10 with a 4.3L engine.

Every thing for the serpentine system is different including the water pump so make sure you get the whole deal when getting. But once you have it on there you can forget about it.
2002 Chevy 2500HD 4x4 8.1/ZF6sp RC/LB
2001 Chevy 2500HD 4x4 6.0/4L85E EC/SB
1997 Chevy Blazer 4x4
1994 Chevy K-2500 4x4 C6P 5.7/4L80E
1979 Chevy K-30 4x4 4sp 4.10
1977 Chevy K-30 4x4 4sp 4.10 454

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