c-squared

We were recently track testing an FC that we had installed a freshly rebuilt engine into, including a new Mazda OEM waterpump. After about 30 mins of running, the water pump-housing-to-front-iron gasket blew, top-right hand side. We changed it, and 30 mins later, it blew again.

We took the car back to the shop, took off the water pump housing, and the mounting ear came with it (Upper left hand moutning stud, looling towards the engine). A little disturbed, we dissassembled the engine, replaced the front iron, and all o-rings. We assumed the original iron had been cracked to begin with, so we re-used the same water pump housing and water pump after checking the gasket mating surfaces for trueness. We replaced the gasket spacers on the necessary studs, and used a completely different set of pulleys from another engine.

We ran the engine on the street to test it (which was a little hairy), and AGAIN, the gasket blew. We towed it back to the shop, now very perturbed.

We took it apart, and found the ear was forming a crack, again. This same iron had been dye-tested for cracks less than 60 miles of running prior. After a little thought, I decided to check shaft play on the new Mazda OEM waterpump, which was non-exsitant. Next, I checked the runout on the main, and waterpump pulleys. The main came back with about 1/1000 of runout, and the water pump pulley came out at 32/1000th! I took off the pulley, and checked the water pump hub.
32/1000th's runout, on a NEW pump.

We replaced the pump with a second Mazda OEM water pump, which had no measurable runout on its hub. We re-ringed the engine with a new front iron, and have been testing the car for over 18 hours now without any problems.

We showed Mazda the run-out on the pump they provided, and they apologized and are working out compensation for the parts we had to replace during the rebuilds.

While there are other possible alternate fixes to having the ear broken off other than replacing the iron and doing a rebuild, this kind of thing should of fix should be completely unnecessary, ever.

The moral of the story: Don't make the same mistake we did. Even if a part is brand new, make SURE it is within OEM specs.


I can just see all the guys who have recently replaced their pump scampering off with dial indicators in hand....

Project84

Damn, that sucks man. At least they are considering compensating you instead of just saying, "well you should have measured it before you used it."

c-squared

We have an account set-up through them, as well as our Mazdaspeed account. It would be unprofessional and costly for them to attempt to negate their responsibilities.

I am merely thnkful that this happened to us, where we ahve the means and funds to deal with such an issue, as opposed to private owner.

Project84

Yeah, I couldn't afford to have that happen. Sucks that it had to happen to anyone, but better you than me