The V8 Owners Forum -

Some good points, thanks. With regard to the rust, as the engine is off the road each winter and the impellor is rusting, I imagine the rust pattern is due to this and rust sinks to bottom half. Also, engine was dried stored for quite a few years whilst I was building the car. I'll have a go at cleaning it as suggested.

In looking at this, I'm puzzled as to me it looks as though impellor is the wrong way around. Serp pumps go anti-clock so in photo above impelslor goes clockwise. That means the scoops do not scoop the water but their backs do. Is this correct? Can't believe this could be wrong though as it would appear to be out of the factory that way.

(New pump on its way.)

Follow on (stupid?) question. I need just two of the long fixing bolts and there are kits out there for Thor, Gems, etc, versions. I thought all Serp engines were the same here. How do I tell, please?

Mine is a 1997 TVR Griffths 500 engine with 25mm ish wide serp belt.

The blades are correct. They throw coolant away from the centre. If you rotate it backwards then it would pull coolant towards the middle.

Any comments on my previous post regards the gasket surface black area?

Different length bolts for the Serp cover with a dizzy. 20mm thicker approx

DEVONMAN wrote: ↑Sat Dec 30, 2017 1:05 pm The blades are correct. They throw coolant away from the centre. If you rotate it backwards then it would pull coolant towards the middle.

Any comments on my previous post regards the gasket surface black area?

Different length bolts for the Serp cover with a dizzy. 20mm thicker approx

Apologies for delay but lost the Forum when it changed hosts - back on track now.

Oh, I see and as my new pump has arrived, it has the same paddle direction so all was well..

As for the black mark, well spotted but on checking, it is just the backing of the gasket so no corrosion at all.

In the end I bought a set of new bolts for my spec so we will see.

Since basically there was nothing wrong with the pump, I've started to make up a cowling as discussed at length above so will see how that works.

At the black area, is there corrosion of the front cover gasket surface. In the pictures it looks like there is some corrosion?

DEVONMAN wrote: ↑Sun Jan 07, 2018 9:11 am At the black area, is there corrosion of the front cover gasket surface. In the pictures it looks like there is some corrosion?

In a word, no. Pictures are showing the broken gasket. Only corrosion was the (probably slightly +) rusting of the impellar.

Hi Richard,
To me that photo also looks like the coolant level was just over half way up the impeller.
Tried searching to see photos of used front covers and this ebay image shows much more uniform colour.
https://www.ebay.co.uk/itm/LAND-ROVER-D ... 1979167222
http://www.britishv8.org/articles/buick ... covers.htm
If the rust had dropped to the bottom then wouldn't you still expect to see similar colours in both the block coolant passages, not the green in the left hand one and brown in the right hand one?

Regards,
Tom.

Hi Tom, appreciated ...

My logic is ...

First, I have three bleed points - rad top, heater hose top being highest point of the lot and I also use the TVR bleed point adjacent to the gauge and ECU sensors at the very top of the cooling chamber close to No 1 injector. I thus cannot see how to bleed air any other way. I also jack up front to ensure connevction hoses can be bled via rad vent.

Yes, I could have air trapped in pump housing which would reduce flow but cannot yet see how to get rid of it.

My theory is .. Return water from rad enters pump via inlet tube in pump. Water comes out via centre of impella and the pump spins to circulate via both left and right channels in above photo. (or does water flow one way left to right / right to left?). Anyway ..

When running, water circulates all OK (ignore possible air lock). My engine is not used much (800 > 1000 miles per year, once every week or two) and indeed is off the road Oct to March inclusive. So when engine is not running, the impella rusts and rust drops to the right hand pump chamber. Yes, agree it looks as though pump chamber has air in top half and so left half has clean water. The left side is green as there is no rust from impella there as it cannot get over the top chamber. Right chamber has rust from impella. Pump inlet is a brownish colour but really just a dirty colour. Water from engine is a bright green / blue colour after a year in there so spotless IMHO.

So, perhaps the real question is that if I have air in pump chamber, how can I get it out? (or am I still correct in thinking rad is not able to cool water enough so need a cowling as per all the above posts.)

I had a problem once with a pump where the gap between the impeller and the pump body was larger than normal (What ever normal is, but the new pump I fitted had a smaller gap). It might be worth comparing the new and old pump. In my case the new pump cured my overheating problem.

Here's hoping!

richardpope50 wrote: ↑Sat Jan 13, 2018 10:47 am Here's hoping!

If the flow was poor, I'd expect and odd reading between in and out on the rad?

OK, new pump will be fitted and cowling half done so will go with that for now (as well as putting back thermostat and heater bypass). Will post a few pics in due course plus results but as I have to have an eye op so it could be a few months. Thanks for all your help / suggestions.

Good luck with the op.

Thanks.

Eye op that does not sound good, so best wishes for it.

I would hang fire installing the pump
Make up a Bung to fit the water passage and attach hose pipe on each side in turn to make sure water flows through both.

But easier to do this sort out f thing on the drive way in warmer weather.

Ian