I recently fitted a new water pump to my 325 but I can't seem to get a decent seal. I used the gasket that came with the pump, but it appears to be crap!
I'm going to have to take it off and try again - and ideas as to how I can achieve a water tight seal??
Leaky water pump
Moderator: martauto
-
android
- E30 Zone Newbie
- Posts: 86
- Joined: Mon Jan 10, 2005 11:00 pm
You probably checked but it bears repeating : you have to be very careful to get every trace of the old gasket off. When you think it's off, rub down the block surface with fine 800 wet and dry until the iron shines. Any gasket left on shows up as a black stain.
You can do this with the cam belt on, (try it first), but I found it easier if you take it off, particularly when putting the pump back on.
Put a steel ruler across the mating face of the pump body It should be dead flat. Being aluminium, it is so easy to distort if your bolt threads catch on the pump flange when doing it up. You have to seat it first, then insert the bolts. The cam belt gets in the way of this.
If it's not flat, it can easily be filed up if you are of mechanical mind. (Use a block of steel machined flat, with a hole in it to let the rotor sit in, and then use engineer's blue to rub the surfaces together. File off the high spots). Otherwise it's pretty cheap to buy another.
When I put mine on, I rubbed grease into the gasket to give a seal. Or you can buy the yellow hermetite stuff which gives a hydraulic seal but never sets.
The other, slight, possibility is a machining mistake on the pump. I was very unimpressed with the quality of the machining on the outlet pipe on one I bought from ECP, so I got my money back and got a genuine one.
You can do this with the cam belt on, (try it first), but I found it easier if you take it off, particularly when putting the pump back on.
Put a steel ruler across the mating face of the pump body It should be dead flat. Being aluminium, it is so easy to distort if your bolt threads catch on the pump flange when doing it up. You have to seat it first, then insert the bolts. The cam belt gets in the way of this.
If it's not flat, it can easily be filed up if you are of mechanical mind. (Use a block of steel machined flat, with a hole in it to let the rotor sit in, and then use engineer's blue to rub the surfaces together. File off the high spots). Otherwise it's pretty cheap to buy another.
When I put mine on, I rubbed grease into the gasket to give a seal. Or you can buy the yellow hermetite stuff which gives a hydraulic seal but never sets.
The other, slight, possibility is a machining mistake on the pump. I was very unimpressed with the quality of the machining on the outlet pipe on one I bought from ECP, so I got my money back and got a genuine one.