Waterpump question

[nashvillecat]

I have a waterpump that seems to work fine (engine runs cool) no leaking weep holes. Unfortunately, it is terribly noisy leaving me to conclude the bearing is going or gone.:cry: And no, the belts are not tight because I do not like to over-stress either the alternator, water pump or steering pump bearings. I have another pump that has been sitting on the shelf collecting dust. I believe it is a graf pump, but I cannot locate any markings on the housing. I no longer have the box in which it was originally packaged, but I know the other two pumps for other BMWs are grafs in graf blue/white boxes.

The never used on-the-shelf pump seems tight enough, but it appears to have some slight lateral movement when the nose is pushed and pulled sideways (on the axis of the pulley). Another thing that is of concern is the fact that this pump is noisy in the sense that the seal seems so tight that it has a slight low pitched squeal. I can state unequivocally that the other pumps on the shelf do not emit any noise and are tighter and do not offer the same lateral movement. Fortunately, replacing the pump on an M30 engine is not a day-long or terribly expensive process. Nevertheless, I do not like having to repeat the same work twice and I am cheap when it comes to flushing almost new antifreeze down the drain.

If anyone out there has a waterpump nearby or recently replaced their pump, perhaps you could offer some subjective observations about the play in the pump and any noises encountered. I am aware that not all pumps are the same and that some pumps may even be self-healing with a little wear and heat cycling. This unused pump will hold pressure via its weep holes (I have tested them) but that is no guarantee the pump won't fail from the beginning. After all, the currently installed pump works find despite being loose and not showing any signs of leaking.

Should I ignore the warning signs and try the pump? Or am I wasting my time?:?:

Thank you in advance.

 

[Honolulu]

well....

A water pump is about $45. It might take two hours to R&R a pump, depending on how agile your fingers are, whether you ever replaced a pump before, and whether you put antiseize on the bolt threads last time.

Also and most importantly, how many of the mounting bolts will snap off because they have rusted themselves to the block. You can do without one, maybe two, as long as they aren't next to each other.

Pumps are readily available, so until the spare pump is used, it's $45 being wasted.

I would snug the belt so that with two fingers you can twist it 90 degrees at the longest pulley-to-pulley span. Then I'd live with the pump that's on the motor, though I'd check it frequently for a while, less so after a week or three as long as it seems not to be getting worse. At the first sign of leaking, though, out it comes.

Others may feel differently. First-time pump replacement is a moderate hassle but not a difficult job, as long as you're careful with the little bolts, and before you reinstall, run a tap in the holes and slather with antisieze. Drain and remove the radiator first.

 

[DJSimca]

I swapped the waterpump on my car last summer. A couple of points for you to consider:

1. Grip the front end of the waterpump by the fan and pull it back and forth. If there is any play at all I would replace the pump .. and not with your on-the-shelf pump which also seems to have play in the bearings
2. Are you certain the noise is coming from the waterpump. Could also be a worn out viscous clutch .. especially if your car is fitted with the early type clutch (before 10/73 I believe)
3. Renewing the water pump is part of general maintenance .. especially on cars as old as ours. If the antifreeze is new I'd just reuse it after changing the pump

Rgds,

 

[nashvillecat]

waterpump woes continued

Thanks for the responses.

I have changed my fair of share of pumps. There is no doubt the current pump is the noisemaker. I use a viscous coupler and with the fan and clutch removed, you can spin the pump by hand and hear and feel the noise. I have since pulled the pump and I am amazed that it still held pressure and did not leak considering how loose and worn things seem to be. I can spin the shaft and it will actually keep rotating as though there is very little friction involved.

I am aware that the M30 pumps are some of the easiest to remove and replace. But my concern was about the off-the-shelf pump which looks brand new, but as I said, seems tight to turn, makes a low squawking noise and seems to have a little bit of lateral play where the fan clutch attaches. I know that it would be optimum not to have any play, but I was hoping someone could confirm that "some" play in these particular pumps is acceptable and that the squawking would disappear with use. I probably would not have even asked the question had I another pump handy for comparison purposes. (No dealers or parts houses nearby)

I may try running this unused off-the-shelf pump with straight water to see what happens. By the way, I rebuilt this engine and had no issues removing the water pump bolts which I previously treated.

Thanks again.

 

[larkinca]

I had a waterpump failure about 350 miles from home that chopped my radiator and fan to bits. Before we left on the trip, all I had was a noisy bearing - no leaks. If you have a noisy water pump bearing - replace it now!

Regards,

 

[Ecto]

Same opinion ! Well spent 45 bucks !