Coolant not circulating ('74 Midget 1275)

I've recently bought my Midget out of storage after 4.5 years and am in the process of getting it back on the road. Leaving it standing for this time seems to have caused a couple of problems.

I'll restrict this post to the cooling system

The problem is that the cooling system is not circulating the fluid. The top hose is getting hot within a couple of minutes, the hose to the heater is getting warm but everywhere else is staying cold. To resolve so far I have tried

1. Flushed the whole system in both directions a number of times (including the heater matrix) In either direction the water is flowing freely and clean. Each time I have done this it has been at mains pressure.
2. Removed the thermostat
3. Checked for leaks and airlocks (I am pretty certain that I have neither).

Maybe the water pump? However this is running as quiet as it ever has and there is no obvious freeplay on the pulley

Any suggestions gratefully appreciated?

Thanks
James

Im not sure if its possible but maybe the shaft on the waterpump is spinning and the impeller is not.

or the belt is slipping on the water pump

Its not the belt thats all OK

your next step is to remove the water pump and take a look. not much to these cooling systems.

you said you removed the thermostat, even with it out the water isn't moving?

Thanks Joe,

No even with the themostat removed there is no flow

well, it seems like you verified there are no blockages, no air in the system, and you removed the thermostat, so it has to be the water pump, right?

James i have this same problem with my 75 1500. I have posted a few times with no real answers. Checked all the obvious stuff, blockage, belt slipping, condition of the pulley, impeller still don't know how much flow there should be.
I would think that if you take out the stat & hose off run the engine for a short time it would pump out the coolant out this is not happening.
With all of this experience on this forum someone should know.? Thanks in advance!

I've actually been having a similar problem and the fact that more than one other person is experiencing it is troubling me.

After returning the radiator to the car during a steering rack change I noticed the car overheated and there was no flow. I replaced the thermostat and a new radiator will be coming tomorrow (it was leaking a little bit). Like James I have no play in the water pump fan and there is no slippage of the belt. I'm really hoping I don't have this new mystery problem.. Guess I'll find out tomorrow afternoon :(

One more thing to check that I haven't seen previously mentioned is the lower radiator hose. If this hose is old and soft, it can collapse from the water pump suction and prevent circulation. It's a long shot, and I've only seen it once on a Ford Truck after 30+ years of being a shade tree mechanic. This is why some return hoses have a spring inside them.

Jerry

are you all running the revs up, to see if the water is circulating? at idle, circulation is slowed down a LOT. maybe you are not giving it enough time to first warm up, then circulate?

Thanks for all the suggestions. Removed the pump today and whilst the pump itself is good the pump inlet was blocked with a white toffee like mass. Not sure what has caused this. I've never used a leak sealant which is the only thing that springs to mind....

THats one ticked off, on to the next one!

nice !

My problem was fixed with the new radiator - Man, that thing looks sharp with the nice glossy black paint! Much nicer than my rusty old hunk of metal ;)