The Water pump debacle thread

[Scallops]

I would very careful about pressing the impeller off - they are inclined to break!

What does Dave mean about it being too tight? Is the impeller rubbing on the housing, or does the bearing seem tight?

Cheers Charlie

The impeller isn't rubbing on the housing - it has the specified 0.5mm clearance - killer said he thought it was just the seal bedding in. The bearing is tighter than the original, but I assumed that was because the original is very well worn - if not almost too worn. We did add some thick oil into the bearing grease point before putting the locating screw back in too.

I reckon the pump might actually be fine - but I shall defer to Killer and Dave's better judgement with all of this - so let's see how it all goes.

[Blknight.aus]

its got the feel of over tightened bearings, a quick spin up for a minute or so on a drill with the pump in a bucket of water to keep it lubed will soon tell what its going to do. If it frees up its the seal and a combination of your oil and the OEM packaging grease getting bedded, if it doesnt free up it may be too much compression on the bearing shell in which case theres nothing that can be done about it other than to let it bed in and hope the case hardening doesnt give up.

[Scallops]

Killer is pretty confident it's just the seal bedding in Dave - we spoke about this last night. Perhaps he will elaborate.

On the sorting this still side of things, Killer is getting some 1/4 helicoils and the bolts I'll need to get this job done. He has the 3 different water pump bolts as templates.

[Killer]

The bearing had the normal feel of a sealed bearing, it was a hand push into the housing, the shaft became tight to turn, after the inpellor was pushed onto the shaft, I am pretty sure it is just the friction of the seals carbon ring on the impellor face. What Dave suggests, ie. running it in a bucket of water, sounds like a good idea to me.

Cheers, Mick.

[toad]

I have just gone down the replacement pump issue with my 55 86" and offer a few observations:

1. If your original pump and thermostat housing are aluminium then unless in perfect condition consider dumping them and get new replacement cast iron ones. Replacement thermostat housings were readily available from UK suppliers (I got the housing and thermostat cover).
2. The replacement pump I brought did not fit well and required the following mods:
a. filing of material adjacent to the timing cover housing to allow the pump to twist into position so the top water access hole was parallel with the bottom edge of the thermostat housing.
b. When in the correct position two of the holes did not line up (as a matter of fact you could not get all bolts to fit in any position); so the offending holes were drilled out oversize to allow all bolts to fit.
c. The gap between the top of the pump and the bottom of the thermostat housing was larger than the o-ring/copper fitting so the use of RTV rubber and some fibre washers was required to seal the gap. This was left overnight before fitting with more RTV on the mating surface.
d. The fan bolt holes were metric! 4 by metric bolts were required grrr.
I now have a running system with no water leaks. Well worth the effort to get it right; just a pain in the process. Oh, the thermostat does not form a seal between the housing and the top cover (as per the V8), it seals between the top cover and the thermostat itself hence the two gaskets either side of the thermostat - it is intended that there is a gap between the housing the cover. Now don’t get me started on brakes…
Toad.

[Blknight.aus]

The bearing had the normal feel of a sealed bearing, it was a hand push into the housing, the shaft became tight to turn, after the inpellor was pushed onto the shaft, I am pretty sure it is just the friction of the seals carbon ring on the impellor face. What Dave suggests, ie. running it in a bucket of water, sounds like a good idea to me.

Cheers, Mick.

that concerns me a little, last couple of pumps Ive rebuilt the bearings have been press fit into the housing, (not a hard press fit but not just push in by hand) pressing the impeller onto the shaft didnt change the rolling resistance of the shaft. Ive had some that have had the resistance change when the bearing shells pressed all the way home but they freed up within a couple of hundred rotations of the shaft.

Time will tell.

[123rover50]

I have just gone down the replacement pump issue with my 55 86" and offer a few observations:

1. If your original pump and thermostat housing are aluminium then unless in perfect condition consider dumping them and get new replacement cast iron ones. Replacement thermostat housings were readily available from UK suppliers (I got the housing and thermostat cover).
2. The replacement pump I brought did not fit well and required the following mods:
a. filing of material adjacent to the timing cover housing to allow the pump to twist into position so the top water access hole was parallel with the bottom edge of the thermostat housing.
b. When in the correct position two of the holes did not line up (as a matter of fact you could not get all bolts to fit in any position); so the offending holes were drilled out oversize to allow all bolts to fit.
c. The gap between the top of the pump and the bottom of the thermostat housing was larger than the o-ring/copper fitting so the use of RTV rubber and some fibre washers was required to seal the gap. This was left overnight before fitting with more RTV on the mating surface.
d. The fan bolt holes were metric! 4 by metric bolts were required grrr.
I now have a running system with no water leaks. Well worth the effort to get it right; just a pain in the process. Oh, the thermostat does not form a seal between the housing and the top cover (as per the V8), it seals between the top cover and the thermostat itself hence the two gaskets either side of the thermostat - it is intended that there is a gap between the housing the cover. Now don’t get me started on brakes…
Toad.

Ill put in my 2 bobs worth too.
Same thing with my steel pump. Bit of grinding to fit and open up a couple of holes. No problem.
For the O ring. Notice a thread cut onto the hole to thermostat housing. Same thread as an air hose fitting.
Machined one down in lathe to fit. Screw in, Bought a fat grommit at the rubber shop. Slipped over the air fitting. Then put the Thermo housing on top. The machined air hose fitting went up into the T. H. a little bit and stoppes the grommit moving out of position. All seal well.
I like those pumps and have ordered another as a spare for another project.
Didiman.

[Killer]

that concerns me a little, last couple of pumps Ive rebuilt the bearings have been press fit into the housing, (not a hard press fit but not just push in by hand) pressing the impeller onto the shaft didnt change the rolling resistance of the shaft. Ive had some that have had the resistance change when the bearing shells pressed all the way home but they freed up within a couple of hundred rotations of the shaft.

Time will tell.

It was a pretty tight hand push into the housing, what I would call a good transition fit, the bearing cant turn in the housing as there is a locating screw. The resistance changed after the impellor was pushed on because the seal face rubs on the impellor face, I would be more worried if there was no increase in resistance as it would mean the seal was not contacting the impellor.

Cheers, Mick.

[Scallops]

Well - Killer came around last night with a plastic bag which I'm hoping can put and end to the 7 week epic that has become me replacing a water pump - although, I am the last person to assume that this might actually be the case!

I have the helicoils and tools to install them - plus a new set of 6mm bolts to attach the pump. According to Mick - one bolt is slightly too long and might need to be hacksawed to length.

Wish me luck!

[abaddonxi]

Don't need luck it'll be sorted in a flash.

My 110 is still sitting down the back waiting for a gearbox. And I think it's been waiting since before the water pump debacle.

I'm aiming for Christmas.