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Old 11-08-2017, 10:39 AM
v8volvo v8volvo is offline
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Join Date: Jun 2009
Location: Northern Rockies
Vehicle: '86 745, '83 764
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Tom Bryant had some improved versions built, info at the link ngoma provided. They are new castings and strengthened. His price for them was not cheap 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. In order to achieve the lower mounting position 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. The 240 bracket can be used on the 740, but the 740 bracket cannot be used on the 240 because of that upper rad hose interference. Fortunately the replacement brackets Tom had made are the 240 version, so they will work on any vehicle.

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 then again most of mine have been 740 style which are slightly more robust, and I also might just have been lucky. Your outcome might vary and any positive results related to the procedure above are anecdotal at best.

I believe the fundamental reason these have such a high rate of failure 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 every time it runs, the aluminum head expands and grows taller, then contracts again when the engine cools off. The repeated stress cycles on the bracket caused by 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 340k
1983 764 D24T/M46 135k
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