Water pump and rpm

[Hantsdave]

I had an interesting conversation today with my Jeep engineer (sorry for the bad language) who was BL trained and served part of his aprenticeship working on Stag engines.

We were discussing the issue of the water pump and he said their main problem was one of insufficient lubrication, i.e. there is no oilway lubricating it and it has to rely on the splash from No.1 running gear? I think he said......

In order for sufficient splash to do its job the tickovershould be 1,000 rpm, which explains the familiar clunk when engaging drive on an auto box. BL discovered early on that part of the problem with failing water pumps was insufficient lubrication and they sent out a directive to their agent garages to ensure the change in tickover spec.

According to my pal, anyone who reduces the tickover to, say 600 rpm, is storing up trouble for later on. Apparently they switched to bronze bushes to help address the problem, ie they are easier to replace.

What my friend is saying seems logical and I will be interested to see if anyone else has heard of this situation.

Cheers

David.

[Kevin Garrod]

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I suppose if the situation you describe is indeed true it would only manifest itself in Stags that spend a significant amount of time in traffic (however much that is) and therfore at idle. From memory, mine idles at around 700 in gear and I think a little under 1000 in neutral (possibly more, must check!)

[Hantsdave]

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Kevin, you're supposed to be packing, not playing on here!!!!

D.

[John Wright]

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This is one of the reasons I have been considering an electric water pump to use in addition to the original pump (see my post on this subject). My current plan is to move the alternator to the nearside and install the electric pump in the bottom hose. A thermostatic switch would then turn on the electric pump if the temperature rises five degrees above the normal level. This is not a particularly cheap option unless you consider the cost of an engine overhaul!

John

[Mark S]

imported post

Hantsdave wrote:

We were discussing the issue of the water pump and he said their main problem was one of insufficient lubrication, i.e. there is no oilway lubricating it and it has to rely on the splash from No.1 running gear? I think he said......

Apparently they switched to bronze bushes to help address the problem, ie they are easier to replace.

I can see that the only lubrication would come from the jackshaft front bearing spill, but the pump lower bearing is a shaft with a flat on the side running vertically in a bush, which willact as an oil well,and the top is a cage bearing, both of which only need the occasional splash of oil.

I would suggest the cooling problems are down to the radiator not dissipating enough heat due to poor air flow, so Ican't see how increasing the flow of coolant around the engine would have a significant effect on this. Increased coolant flow would be a benefitto increase turbulance tostrip off and collapse slightly more of the theinsulating layer of steambubbles that form between metal and coolant,but this only happens near boiling point and I would have pulled over five minutes before anyway.An EWPis a sledge hammer to crack a nut IMHO.

I would use the money to buy either / and - an alloy rad. A spoiler if you are overheating on the move or a big electric fan if overheating at tickover.

Has anyone tried Water Wetter? Does it work or is it snake oil?

Mark.