Info needed: Morris C8 radiator

[pauldavies]

Yes Mike I will give the C8 another run possibly Wednesday and if no luck then I will be appealing to the MLU for new old stock spring, filler funnel and a rubber seal, I have been on ebay for some spark plug rubber caps and have repaired my exhaust box. They make these exhausts out of soft steel these days as I bent the joins with my fingers, when all is right I will replace with stainless.
Regards
Paul

[pauldavies]

Had for a run in the C8 and yes it blew out the coolant again, as soon as it started I stopped and let it cool off filled up and got home. A major setback so I am on the lookout for a new spring, filler tube and rubber seal. I have contacted Wheels & Tracks who seem the most likely but no reply yet, if anyone has these items I would be pleased to pay for them.
Paul

[Mike K]

That's bad luck . Must be frustrating for you each time it plays up like that.

To be honest you will have to experiment with a replacement spring from somewhere that is close to the original specifications. Rolf Ask in Norway had a container load of Morris NOS stuff , mostly 4 cyl. but. where it all ended up is anybody's guess. He had new radiators and even a NOS engine block plus many other items, all ex Norwegian Govt. stock .

NOS parts for these Morris trucks are very thin on the ground just about non-existant. The CMP guys don't know how lucky they are !

[pauldavies]

Mike more than frustrating but sort of get used to it, been in touch with a couple of sources but nothing yet. Maybe try one of the spring makers if I get blanked out as there are a few of them that do individual springs, I was going to take the C8 up to Bundy for our MJCQ club weekend next week but the Austin champ will do nicely.
Regards and will let you know of any success.
Paul

[Richard Farrant]

Hi Paul,
I have found some info regarding the Air-Lock filler as fitted to your Morris, and Bedford QL. It is not a pressurised radiator. There is no overflow tube as in some radiators. To quote:
"To prevent dilution of antifreeze caused by careless topping up, an 'Air-Lock' type radiator filler is fitted. This filler incorporates a spring loaded valve in the filler tube which permits steam to escape through relief holes in the cap, no overflow pipe being used. The filler cap must screwed right home to open the air lock valve in the filler."

I had similar problems a few years back on the QL and was not filling the rad more than in the past, but I did find the thermostat was stuck open and wondered if it had been playing up and sticking shut as well. Water would blow out and coolant temp was normal, it would then stop blowing out and run normal until it would happen again for no reason. I changed the thermostat and stripped and cleaned the Air-Lock, did find the adjusted ring depth was not correct, so reset it. Watch that you are not overfilling the rad.

regards, Richard

[Mike K]

I agree with Richard and we should have thought about the thermostat ages ago.

My C8 ( the little CMP 4X2 ) would blow coolant out the radiator cap with some force , usually after climbing a hill. At the time, I was running it without a thermostat .

The thermostat does a important job , but it has a second function, it restricts the coolant flow into the top tank , without this restriction, the coolant fills up the top tank and eventually pressure builds up and it blows out.

I would check your thermostat . Is it the correct type ?

My CS8 4X2 has a different cooling system . They fitted your type to the 4X4's .

[pauldavies]

Guys there lies the conundrum "no thermostat", don't use them here in QLD but maybe I will need to find one! I purchased some bronze today and will make a new filler tube and castelation ring on Wednesday, I am borrowing a friends lathe to do the job. The spring I am sending to a company in Brisbane to make a stainless replacement as no-one does bronze springs anymore, I haven't overfilled with coolant as from your early advise Richard I just touched the core and at least 4 litres of coolant blows out so it is excessive and that is with stopping straight away. It is interesting that it blows as the temp gets to running temperature so the thermo theory could be correct. Any idea on spring tension?
Regards
Paul