13 replies to this topic

[Orange SS]

my waterpump decided to start leaking and not knowing there was 2 different impellers available on aftermarket pumps, the one I bought from repco does not have the cast impeller and I painted it black before I even realised I had bought the inferior of the 2 available. the one I am removing has only done a few hundred km's which is disappointing.

 

How much difference does using the galv steel impeller compared to the cast impeller? Would thermostat choice, radiator and fans make up for not having a cast impeller? THe repco pump is normally $130 whereas the cast impeller pump is only $50 so that kind of made me believe I was buying the better of the pumps.

 

I have just fitted a 355 stroker, 3500 stall and I am about to upgrade my davis craig fans to a twin derale thermos with 3850CFM so there shouldn't be any cooling issues if the pump I have will be good enough.

 

Anyone with experience in comparing the 2 pumps?? Should I use the one I bought, or go and buy another one?

 

 

[Cook]

Hi Matt. Smarter people on board will surely let you know but I believe the problem is the pressed steel impellers don't last as long., Ie the vains.  Cheers Ron

[LHSL]

I have had the crap water pump (with the steel fins) on a red 6 for the last 20 odd years. Took it off because I was doing a freshen up. The impellers lookef fine they hadn't worn away like people say they do. I am sure v8s will be the same.

[Orange SS]

So there’s no noticeable difference between their pumping abilities when new?

At more than double the cost of the $50 cast impeller type I had thought the repco pump may have been superior.
I’m happy to keep this one if it’s a longevity issue not an operational issue.

[Ando]

Matt,

 

I've got the steel impeller small bearing short pump on my stroked motor.

It's a stout motor..530 hp, cammed for high rev. power with a Gilmer  pulley on the water pump.

 

I went through the same thing, listening to others with mixed opinions about the small bearing issues & inferior steel impeller.

Even bought the later big bearing cast impeller type. Now it's in stock.

 

After having a good look at it, I took a punt & put it on, only because I reused the mechanical fan & spacer.

 

Been 2 years now with no issues regarding leaks, cavitation  or bearing wear. 

 

Cheers

[I'm a Red Motor fiend]

The last cheap steel impeller pump I had corroded so bad it actually lost a couple of blades completely. I have not used one since.

[Orange SS]

the repco water pump seems to be good quality. As I have painted it black I cant take it back so it's going on my engine today. I'd seriously doubt it'll corrode away in my lifetime but I'll regularly check the inline filter on the radiator hose for any signs of corrosion which is more than normal.

 

I'll have to wait until summer to test it out on a 40deg day with the factory air conditioning running but with a brand new brass radiator, new shrouded twin fans that can operate at 3750 CFM plus I have the standard dash engine temp as well as a more accurate temp gauge fitted up now - I shouldn't have any overheating issues(I hope).

[LJ RB30]

Are people with corrosion issues using coolant?
Have certainly fitted a few pressed metal impeller pumps in my time with no reduction in cooling & removed some with varying decay from zero to bad.
Pumps I’ve changed were mainly due to seal leaks or bearing noise/movement.
No doubt there are some low quality metals in some pumps out there.
When I get a chance I’m gunna have a look at some of the old pumps I think I still have laying around cose I’m pretty sure I’ve seen stainless pressed metal impellers on some pumps.
Obviously they will be much better than plated mild steel!

[I'm a Red Motor fiend]

Ok so I'm a chronic hoarder. Got home and dug this out, haven't seen it for years so it's only lost one blade not two as I said originally. GMB brand.
This was over ten years ago so can't remember if I was running water or coolant, there probably is a connection.
At the end of the day tho, the one you have will pump water and may serve u for years before it fails if at all.

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[76lxhatch]

^ Any coolant with a corrosion inhibitor won't allow that to happen in a hurry, usually the bearing/seal will fail long before it rots. Unless you never drive it and leave the coolant level low.

 

The steel impeller isn't as good as the cast one but it works fine for most. Early (short) pumps with cast impeller are near impossible to find here, you have to change to later model pulley and use the long pump.

[fx48_eh64]

Are we talking V8 ones here?  i didnt think red 6 pumps could be bought anymore with the cast impeller?

[I'm a Red Motor fiend]

I bought a 6 cyl one off eBay bout 18 months ago, not sure if they're still on there

[fx48_eh64]

I bought a 6 cyl one off eBay bout 18 months ago, not sure if they're still on there

 yea can still get them from time to time on ebay,  but pretty sure you cant buy cast ones over the counter no more