Hugh,
I hate to disagree as I'm no expert, but when putting on my oil cooler the thick washers were required on the studs, inside between the cooler and the block. Without them the cooler would not sit square to the block at all three studs.
In fact, my lower seal kept leaking (I prefilled the cooler specifically to see any leaks after assy), and with a flashlight I could see light passing between the wide portion of the seal and the case. I measured all the accumulated heights for both seals and found that the dimensions for the lower cooler hole were 0.03 off (larger) compared to the upper one - resulting in a gap.
So I located a washer that was 0.03 thinner.
Now I'm willing to consider that just because these washers were on when I took the cooler off, doesn't make them valid, but as I said my cooler didn't appear to sit squarely without them, and the seals would have to be quite "squashed" without them.
Any insights would be helpful. Don't want to have to pull this bugger off after its back in the car.
Regards,
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Gerard
74-914 2.0L
3D914
rodrigos6@juno.com