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Old 11-08-2017, 10:39 AM
v8volvo v8volvo is offline
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Join Date: Jun 2009
Location: MT
Vehicle: '86 745, '83 764
Posts: 1,009
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Tom Bryant had some improved versions built, info at the link ngoma provided. They are new castings and strengthened. He wanted decent money for them to recoup his costs but probably worth it since the originals break repeatedly and good used ones are hard or impossible to find.

The bracket comes in two styles, 240 and 740. The 240 version mounts the pump an inch or so lower to make room for the upper radiator hose to wrap around the mount, which the 740 setup does not do. To do this, the 240 bracket uses a right angle ear on the bottom instead of the straight boss the 740 bracket uses. Both versions are prone to breakage of that lower ear but the 240 style seems especially fragile. Unfortunately, while the 240 bracket can be used on the 740, the 740 bracket is not compatible with the 240 because of that upper rad hose interference. Fortunately it looks like the replacement brackets Tom had made are the 240 version, so they will work on both setups.

In order to reduce risk of breakage, during installation it can help when tightening bolts to make an attempt to minimize stress on the bracket. Usually I will gently tighten the three upper bolts, then tighten the lower bolt, then loosen the upper bolts to allow the bracket to move to whatever position it wants, then retighten them, then loosen and retighten the lower bolt, and continue doing this until I see no movement when loosening either end. Using this method, I have never had a bracket break during use, but most of mine have been 740 style which are slightly more robust, and I might just have been lucky so far. Your outcome might vary and any positive results attributable to the procedure above are anecdotal at best.

I believe the underlying reason these break is because they are mounted on one end to the cylinder head and on the other end to the block. As the motor warms up and cools each time it runs, the aluminum head expands and grows taller, then contracts. The repeated stress cycles on the bracket caused by this, getting pulled on then relaxed with each thermal cycle, probably is part of the issue. On top of that, the vibration from the engine and the PS pump is probably a factor, especially if the rubber pump mounting bushings are worn and allowing excess motion. Keeping those in good shape seems to help. They cost a couple of bucks each and are easy to replace when the bracket is off the car.
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1986 745 D24T/ZF
1983 764 D24T/M46
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