rotor-spin

I previously posted this: https://www.rx7club.com/1st-generation-specific-1979-1985-18/water-pump-gasket-creep-426595/ about a problem with my water pump gasket squeezing its way out from between the pump cover and housing. **** about these things as I am, I unbolted the water pump and housing again, (that makes three times) and replaced the gaskets, to the tune of about $20. This time, I took a friend's suggestion and gasket sealed the gasket on to the cover, and let it almost dry before assembly. It looked like I finally had the problem solved!

That is until I checked the coolant yesterday before going for the first drive of the year, and noticed the gasket had somehow squeezed itself out almost 1/4" from between the pump cover and housing! (both sides of the lowermost bolt) I had only warmed it up and bled the cooling system before this; then it looked like the gasket held just fine. So, now I'm afraid to drive it this way, lest the thing decides to work its way completely out.

So, the problem is, I ordered the pump/cover from Mazdaformance way back in December '04, and I'm thinking the mating surface is warped or slightly beveled. (I read somewhere somebody else had a problem with a warped WP cover, but I think it was a 2nd gen) Mazdaformance appears to be out of business, but it is an OEM Mazda pump.

I'd hate to have to return this pump before getting the new one, leaving my cooling system dry (mmmm, corrosion) while I'm waiting for a new pump. Does anybody know how or if I could get some compensation to get another, but not-warped water pump?

Midwest 7's

iTrader: (4)

i don't understand. is it leaking water when running?

rotor-spin

Not yet, but I fear that if I drive it, the remaining 1/16" of gasket between the castings will work its way out and suddenly... geyser!

IanS

iTrader: (4)

PM sent.. Is it possible to have the water pump cover machined to make sure it is flat? I bet it would only cost a few bucks, especially if it is so cheap. Also forgot to say in my PM that I have a front cover from same engine if you would be interested. Same price as the pump cover/assembly.

7aull

iTrader: (2)

Did you torque to about 15 ft/lbs? Those bolts don't need much tightening!! Also, when I swapped on a new water pump, I put a thin bead of axle-grease on each face- holds the gaskets in place and makes replacement a breeze next time around...!
Stu Aull
80 GS
Alaska

rotor-spin

Posted by 7aull: "Did you torque to about 15 ft/lbs? Those bolts don't need much tightening!!"

I tightened the bolts carefully and in many steps, (in the pattern given in the Haynes manual; studs first, then the three bolts) first by hand to snug them up, (in small increments) then in steps with a torque wrench to 175 inch pounds. (or about 14.5 ft/lbs)

I used 3-Bond (grey pliant) as I always have on gaskets. The manual suggested silicone, but I've always had good luck with 3-Bond in the past. The advantage I could see with silicone is it dries completely to a semi-rigid consistency, so maybe the silicone would have held the gasket in. But really, being pinched between two solid flat surfaces should hold a gasket securely!