Chargecooler pump impeller - RESOLVED

[x6gas]

Still been trying to sort out the problems with my S4...

The latest problem I've found is a shafted chargecooler pump. Looks like the impellor got stuck to the sides of the pump...

I've obviously been thinking about whether to go down the electric pump route or to just overhaul the original mechanical unit.

I can't believe that the overhaul kits are over 50 quid - basically for a rubber impeller.

It looks like Jabsco make a variety of similar impellers - anyone know of one which is suitable for the chargecooler pump? The c/c pump impeller is 20mm high with a diameter of 45mm...

Edited October 23, 2005 by x6gas

[hovgaard]

Just a thought (not necessarily a clever one): Have you considered taking the old impeller over to the boat engine repair shop? It can't be much different from the impeller in your average sailboat diesel engine coolant pump.

Good luck, and keep us posted.

[Daniel]

http://www.lotusespritworld.co.uk/EModific...argeCooler.html

[x6gas]

http://www.lotusespritworld.co.uk/EModific...argeCooler.html

<{POST_SNAPBACK}>

Yup - thanks Daniel. I knew about this.

Just trying to find out if there is a cheaper way of replacing the impeller as I don't really want to down the electric pump route...

[Paul C]

Just trying to find out if there is a cheaper way of replacing the impeller as I don't really want to down the electric pump route...

<{POST_SNAPBACK}>

Wahey!!!

A Chargecooler thread

Go electric. won't ever leak water to oil like my mechanical pump did.

Easy to change, cheap too.

[patpong]

One of these day, I'll try to have machine shop make the impeller out of aluminum. I would think it would last forever. Why did they make it rubber? PUK offer impeller with better rubber material....

http://freudhoefer.de/lotus/esprit/product...ooler/index.htm

Edited October 22, 2005 by patpong

[x6gas]

One of these day, I'll try to have machine shop make the impeller out of aluminum.  I would think it would last forever.  Why did they make it rubber? 

<{POST_SNAPBACK}>

Ah - I had exactly the same thought before taking the pump out but it's not that simple! The pump chamber is not circular, but is squashed at the inlet and outlet. This means that a metal impeller won't work - if it was small enough to clear the narrowest part of the chamber it would be very, very inefficient and shifting the fluid due to the gap around the rest of the chamber.

[DanR]

Could be designed like some oil pumps where the impeller is revolving inside another revolving, eccentric annulus ring. I wouldn't have much confidence in the lubricating properties of coolant though.

Easier to service the original or convert to electric pump.

[x6gas]

Could be designed like some oil pumps where the impeller is revolving inside another revolving, eccentric annulus ring. I wouldn't have much confidence in the lubricating properties of coolant though.

Easier to service the original or convert to electric pump.

<{POST_SNAPBACK}>

No - just a simple impeller with a central d-shaped drive shaft. The rubber veins of the impeller flex in the pump chamber and just have to flex a bit more where the chamber gets smaller (on the output side) and larger (on the imput side). I guess that this arrangement just makes the pumping more efficient...

[Paul C]

No - just a simple impeller with a central d-shaped drive shaft.  The rubber veins of the impeller flex in the pump chamber and just have to flex a bit more where the chamber gets smaller (on the output side) and larger (on the imput side).  I guess that this arrangement just makes the pumping more efficient...

<{POST_SNAPBACK}>

Hey, if you want an old pump to play with/re-engineer to suit a new impeller blade

then you can have mine. remember the shaft leaks to oil though so you need new

'O' rings on that to make it ok to refit.

Oh, and it's got more calcium in it than the milky bar kid too.

[superdavelotus]

Ian,

PNM will completely recon your old pump for about

Edited October 22, 2005 by superdavelotus

[DBredS4]

What you have to bear in mind when spending lots on a recon pump, it is well worth going for the electric for a little more as it turns at a constant high speed unlike the engine speed dependant original and isn't prone to gradual degeneration and failure

WC Eng in the states do one and you can get a blanking plug to seal the hole.

Also I think Demon Tweeks will provide if you give them the right spec.

Dom

[DanR]

Could be designed like some oil pumps where the impeller is revolving inside another revolving, eccentric annulus ring. I wouldn't have much confidence in the lubricating properties of coolant though.

Easier to service the original or convert to electric pump.

<{POST_SNAPBACK}>

I wasn't clear enough. Was referring to Patpong's idea of making it in alloy.

[mchlrodrigues]

It looks like Jabsco make a variety of similar impellers - anyone know of one which is suitable for the chargecooler pump? The c/c pump impeller is 20mm high with a diameter of 45mm...

[

Jabsco mkae two that will fit the charge cooler pump, one in normal rubber and the other in Nitrile. In the US the nitrile ones go for about $14.00 inlcuding the paper gasket. I've used one without incident. They appear to last better than the Lotus rubber ones.

I had the P/N but appear to have discarded it when I went electric. If you go to a Jabsco dealer, they should have a chart on the wall with all of the replacement impellers shown in full size. You can just match it up.

[x6gas]

It looks like Jabsco make a variety of similar impellers - anyone know of one which is suitable for the chargecooler pump?  The c/c pump impeller is 20mm high with a diameter of 45mm...

[

Jabsco mkae two that will fit the charge cooler pump, one in normal rubber and the other in Nitrile.  In the US the nitrile ones go for about $14.00 inlcuding the paper gasket.  I've used one without incident.  They appear to last better than the Lotus rubber ones.

I had the P/N but appear to have discarded it when I went electric.  If you go to a Jabsco dealer, they should have a chart on the wall with all of the replacement impellers shown in full size.  You can just match it up.

<{POST_SNAPBACK}>

Thanks Michael - that's good to know. I was wavering and had almost decided to go the electric pump route...

Anyway, I shall keep going and try to source the Jabsco part. Do you know if it was a marine application or industrial? If you do happen to come across the part number then that would be great!

Thanks again!

[Iain_B]

Not related to the topic, but here in Australia we have a variety of electric water pumps:

Booster Pump

Main Waterpump

A friend of mine down the road ( in Sydney) has the waterpump with the controller in stead of a mechanical waterpump on his V12. The pump seldom runs on full power even with the 40+ degree day we get here and crusing down the highway, runs a minimal rpm. It worked out the same as a new watepump ( bit more than a reconditioned one however) cost wise as well - About $260 AUD for the pump, $250 for the controller and $150 to get a blanking plate made.

Iain Burgess

Brisbane Australia

[patpong]

I think there is two problems with the original pump. one is the weak rubber impeller and the other is the gasket that leak water too often. Is there a better gasket?

Another thing about the electric pump I heard was that if the electric pump fail there is no way of knowing.... true???

[hovgaard]

Drive hard (use the turbo boost) for a while, then put your hand on the chargecooler. If it feels cool, your pump (electric or otherwise) is working.

[Paul C]

Another thing about the electric pump I heard was that if the electric pump fail there is no way of knowing.... true???

<{POST_SNAPBACK}>

Ha!

Mine is wired to an ignition live. When i turn the key before starting the engine,

i listen to the gentle whirr of the CC pump, and the sound of the Fuel pump...

...then i know all is well, and i turn the key.

TBH, you are less likely to know if the original pump has failed?

[mchlrodrigues]

... Do you know if it was a marine application or industrial? If you do happen to come across the part number then that would be great!

It's for a marine application, from a small bilge pump. I located mine at a Mercury Marine dealership.

http://www.jabscoshop.com/category.asp?ls=...B7A1147CC&id=30

I think it's the first one 1414-0003B. I seem to remember the first fiew digits of the P/N.

[mchlrodrigues]

Thanks Michael - that's good to know. I was wavering and had almost decided to go the electric pump route...

If you do happen to come across the part number then that would be great!

One last caution. Looking at the Jabsco site the first item and part number I posted looked the most familiar.

However, the spare impeller I have visually appears like the second impeller with a brown center (as opposed to brass), made from Viton. I would check with Jabsco to confirm whether the two part numbers are for the same part in different material or completely different impellers.

The price difference is substantial, but it would be nice to know what you're buying and make a conscious choice. The spares I bought had a brown plastic center, and hold up quite well.

[x6gas]

It's for a marine application, from a small bilge pump.  I located mine at a Mercury Marine dealership.

http://www.jabscoshop.com/category.asp?ls=...B7A1147CC&id=30

I think it's the first one 1414-0003B.  I seem to remember the first fiew digits of the P/N.

<{POST_SNAPBACK}>

Fantastic Michael - cheers.

The OEM part has ten fins, rather than six, so at first sight would appear to most closely resemble 9200-0023B. I'll give 'em a call to confirm at let you know.

Cheers again - this is keeping the car off the road at the moment as I've got a lot of bits and bobs dismantled to give better access (good excuse to get everything cleaned up, replace any tired hose and renew hard to get to hose clips!)

[x6gas]

Well, thanks to Michael I managed to track down the correct replacement impeller.

The alternative part for Lotus B910E6992F is either Jabsco 9200-0021B or Jabsco 9200-0023B.

Part number 9200-0021B is made of Neoprene, 9200-0023B is Nitrile. Not sure which is the best material - Neoprine is a DuPont synthetic rubber and looks pretty robust so I am going to try that - there is no price difference (

Edited October 23, 2005 by x6gas

[mchlrodrigues]

The alternative part for Lotus B910E6992F is either Jabsco 9200-0021B or Jabsco 9200-0023B.

Part number 9200-0021B is made of Neoprene, 9200-0023B is Nitrile. 

Having sourced the part 10 years ago my memory isn't what it used to be, but at least I was able to point you in the right direction.

Thanks for getting the correct P/Ns sorted out.

Regards,

Michael