Is my water pump belt slipping?

DaveEFI · Post by **DaveEFI** » Fri Sep 20, 2013 10:16 am

Darkspeed wrote:Just install some clear tube from the T/Sat to the rad.

That sounds a good idea - where would you get suitable stuff?

It's easy to see the circulation on my SD1 by removing the rad filler with the thermostat open - the coolant positively whizzes round, and will rise and fall as you rev the engine. (That's with a crossflow rad if it matters)

Darkspeed · Post by **Darkspeed** » Fri Sep 20, 2013 4:22 pm

http://www.ebay.co.uk/itm/PVC-Braided-P ... 19dbcda616

Just the first one I came across but plenty of different options - Opening rad cap is OK as long as rad is highest point.

Not sure what the hose size is but some simple reducers etc will sort it out.

Darkspeed · Post by **Darkspeed** » Fri Sep 20, 2013 4:24 pm

http://www.ebay.co.uk/itm/PVC-Braided-P ... 19dbcda616

Just the first one I came across but plenty of different options - Opening rad cap is OK as long as rad is highest point.

Not sure what the hose size is but some simple reducers etc will sort it out.

DaveEFI · Post by **DaveEFI** » Fri Sep 20, 2013 4:29 pm

Says the maximum temp is 65C - and you'd need the thermostat to be open to see the flow through the rad.

richardpope50 · Post by **richardpope50** » Fri Sep 20, 2013 5:02 pm

So, I decided to remove the swirl pot and this entailed modifying the rad inlet from a 90 degree entry to a straight entry. Cut off the unwanted pipe and saw the problem immediately. The down core pipes were blocked with what appears to be a sand / clay / grit mixture. It has the consistency of clay, looks like sand and has white crystal / gritty bits in it.

After some effort to brush it all out – there must have been a handful of the stuff – I’ve got it pretty clean as far as one can tell. Put it all back including swirl pot and made up a temporary hose to fit the now cut off inlet and started her up.

Fan came on correctly at 92 and cooled to 87 when it went off. Perfect! Then went for a reasonable drive and she kept cool at 79 (until a hose came off!)

So, what this clay type stuff was I know not. Possibly came from my old engine. I’d never have found it as draining the system was always clean water. So now to make some permanent changes including the horizontal thermostat housing and on to the next problem.

Thanks for all your suggestions and help.

DaveEFI · Post by **DaveEFI** » Fri Sep 20, 2013 11:03 pm

Very glad you've found it. Stag V-8s were notorious for having casting sand inside them - but never heard of this with the RV8. Wonder if some aggressive rad sealer was used before you got the engine or whatever?
I've heard of a heater matix being blocked by some of them.

DaveEFI · Post by **DaveEFI** » Fri Sep 20, 2013 11:05 pm

Very glad you've found it. Stag V-8s were notorious for having casting sand inside them - but never heard of this with the RV8. Wonder if some aggressive rad sealer was used before you got the engine or whatever?
I've heard of a heater matix being blocked by some of them.

richardpope50 · Post by **richardpope50** » Sat Sep 21, 2013 8:35 am

Dave, now that's a thought.. The old engine used at IVA time was off a scrap yard SD1. It was drained when I took it out but this stuff may have been inside block and just happened to get pumped in. You could see it blocking the tops of the down core tubes that are small on my rad. Otherwise my rad was brand new.

DEVONMAN · Post by **DEVONMAN** » Sat Sep 21, 2013 8:38 am

Great news that you have found the problem.

It would be good to understand where the crud came from and it's odd that the heater matrix is not blocked also.

Regards Denis

SimpleSimon · Post by **SimpleSimon** » Sat Sep 21, 2013 5:11 pm

I would recommend a reverse flush of your rad, heater matrix and engine block (remove stat) just to make sure you have got rid

as suggested probably from the previous lump

richardpope50 · Post by **richardpope50** » Mon Sep 23, 2013 11:41 am

When my new horizontal thermostat housing arrives I'll get the hose to the whole system. Went for a run on Saturday and it got a bit hot again but think this is because my temporary hose is pinching too much and restricting the flow - or more crud has returned.

I won't tell until it all comes apart again and see inside rad again. I did give the rad a good clear out the last time, though. I'll be altering the swirl pot and rad pipework too as part of the exercise.

At least I got the thing to keep cool the other day so it cannot be too fundamental a problem.

unstable load · Post by **unstable load** » Tue Sep 24, 2013 6:45 am

If you have hard water in your area it could be furring up with scale.
Drain your cooling system and bung in a few litres of white vinegar. Start it up and run it for a while, or even go for a gentle pootle around the neighbourhood for about 30 minutes and then flush and refill.
I did that on my Honda and it made a big difference to the temperature.

DEVONMAN · Post by **DEVONMAN** » Tue Sep 24, 2013 8:11 am

Do you know the full history of your engine?

Is it possible that someone has in the past used one of those "magic" repair compounds to seal a liner problem or even a seeping core plug.

Regards Denis

richardpope50 · Post by **richardpope50** » Thu Sep 26, 2013 5:00 pm

I'm on holiday until next week so will post in a couple of weeks time when I have been able to make mods. Thanks all.

richardpope50 · Post by **richardpope50** » Sun Oct 27, 2013 9:41 am

Well today I finally got there!

Having found all that 'crud' in the header tank and having cut off the rad inlet to remove swirl pot from the system I then had a choice to go back or continue. Much thought and so continued to remove swirl pot from circuit but that then meant ... change (buy) thermostat housing for straight one, buy new fan switch as old one in swirl pot (and too big) and find location for it So converted top hose sender connector from bleed valve to new header tank connector, drill new hole for new fan switch, get rad inlet re-welded. then I waited for two new taps to make threads which seemed to have got lost en route from Hong Kong after four weeks wait. Eventually bought UK ones and now re-fitted it all.

Have been out for 20 mile run and temp stays at 79 with peaks of 82 so well chuffed. So at last that's all sorted and on to some other niggles.

Thanks for all your help.