Which water pump do I want?

[DEV0 E30]

Freshening up an m20b25 I got. I have a predicament.

The one on there is a GMB. It looks like it should, and has 2 hose outlets.

Looks like this:

http://realoem.com/bmw/showparts.do?model=1113&mospid=47309&btnr=11_0577&hg=11&fg=35

I just got a GRAF. The GRAF gasket doesn't fit right at all, at least I don't think so... but I can get another gasket. The problem I think I see is it only has one outlet.



And pretty much every other water pump I see online has one outlet, wtf mate? Is 1 oulet after many years superior to 2? A new GMB pump has a good looking gasket but still only one outlet, is it the lemforder of water pumps? Please advise.

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EDIT

I didn't think they'd change the cooling from b25 to b25. They did, the engine is from an 87ish era, this explains why the gasket fits like a virgin. The pump fits but I'm not sure what to do. The car I'm putting it into is an 89. Does this mean I still need a water pump for an 87? Or not, since cooling on an 87 is somewhat different. I'm perplexed.

For models with production date through 8/1987:

[Dave]

Believe you may need an 87 pump - the cooling system on the 87 M20B25 is different than the later models - radiator and the routing of the hoses is different.

[DEV0 E30]

So I can't use the pump I have? Even if I use all late model stuff?

[DJB]

The cooling system up through 1987 used a two inlet pump, with the second inlet connected to the translucent resevior on the right side of the engine compartment. The problem was that the coolant hoses had to cross the front of the engine, near the fan and pulleys. The cooling system 1988 and later used a single inlet pump. There is a rigid metal coolant tube crossing the front of the engine, and an expensive 'T'-shaped hose that connects to the resevior on the left side of the engine compartment. Again, the design change is based on the date, not the 'e' vs 'i' engine.

[e30_325es]

If your coolant reservoir is on the passenger side, then you can only use the 2 outlet pump. If the reservoir is on the driver's side, then you should use the 1 outlet pump.

[Dave]

Devon,

Are the impellers the same size? Do both of them "fit" the block?

If so, as long as you are using all of the late model hoses, radiator and reservoir, maybe it will work???

As far as the gaskets - you realize that there is only one way they fit - right? The holes are NOT evenly spaced.

[DEV0 E30]

I intend to use the late model setup, so I assume I can use the one outlet then? I obviously don't want anything bad to come from it.

Devon,

Are the impellers the same size? Do both of them "fit" the block?

If so, as long as you are using all of the late model hoses, radiator and reservoir, maybe it will work???

As far as the gaskets - you realize that there is only one way they fit - right? The holes are NOT evenly spaced.

The impellers are different, but about the same size. It looks to fit fine but not the gasket.

That's what I'm thinking. I'm curious if someone has used a late model setup on an 87 engine. I would think it would be fine but would like to be sure.

Yes, I tryed every way and I don't think it's going to fit right.

[MR 325]

Seems to me that you can use the pump according to the cooling system you're going to use. If you're using all late model parts, sue the late model pump. This has always been my understanding anyway.

[DEV0 E30]

Yeah, I just want to make sure the water pump hole in the block isn't a different size or off by a few mm so I'll have a constant leak or anything. Looks like I'll just continue ordering new late model stuff then.

[MR 325]

Yeah, I just want to make sure the water pump hole in the block isn't a different size or off by a few mm so I'll have a constant leak or anything. Looks like I'll just continue ordering new late model stuff then.

On the turbo car I had a 87 block with all late model everything else, no issues.

[DEV0 E30]

Cool beans.