Morris Minor Owners Club

Hi,
just wondering if anyone knows why this would happen...We were driving along quite happily then suddenly bang...brown water splattered all over the bonnet and then steam everywhere...managed to pull off the busy road...
On close inspection the radiator has blown at the front seal near the bonnet catch...and before you say it...yes it did have enough water in...and yes the cap/pressure valve appears to be OK...
We'd only been driving for 10 minutes...!

By the way Duncan is a 1952 Series MM

Any thoughts?
cheers,
Chris

Probably internal corrosion that has eventually given way until it let water out.

Take the radiator off and get it pressure checked and repaired.

Hi Cam,
wouldn't it be easier to get a replacement...the seam is gapping...so don't think pressure checking will help...

Have it recored. That way you keep both tanks. Then you get a new core, and they solder the old tanks to it.

I know, it's me job!

Scottishmoggy wrote:Hi Cam,
wouldn't it be easier to get a replacement

Yes, of course, and if you can afford to do so then go for it!

...the seam is gapping...so don't think pressure checking will help...

Well, I did say pressure testing and repair, so if it's visibly gapped then that will be your problem of course. In your initial post you did not seem to know what was wrong, so that's why I suggested the pressure testing also.

But you have to wonder why there was a 'bang' ? To get that would suggest a sudden release of high pressure. I wonder if the head gasket has blown into the water-ways.

And with the sidevalve, one would not expect high pressures, even if it is fitted with a waterpump.

...brown water splattered all over the bonnet

And don’t forget after replacements to fill up with a good anti freeze, with corrosion protection. When it’s highly polluted, you must renew the anti freeze for a little while.
Has Duncan a side valve engine? Especially the alloy water housings and the alloy dynamo mounting are sensitive for corrosion.


Greetings from Holland,

Wimor

Thanks chaps for your helpful suggestions...Cam, I thought the water was from the blown seam in the radiator...but didn't know why it should happen...Perhaps Bmcecosse has a point about the head gasket...but how would I know?

I seriously doubt that it's pressure related as the cap releases the pressure at 4 pounds. Is the cap in good condition and thhe 'spring' not sticking? If it has blown out the seam then the cap would have to be stuck.

The cap seemed to be ok and not sticking...but what the point that Bmcecosse is making about the head gasket?
As you can guess...I'm pretty inexperienced when it comes to cars...just love driving them....

check both the oil and the water for traces of either fluid. How was the oil pressure, just before "the accident"?
Did you have proper coolant in the rad, or just plain water? And if it was indeed water, how cold was it the night before?

How long have you had that radiator btw? Sometimes the soldering tin isn't as strong on all places

...but what the point that Bmcecosse is making about the head gasket?

You can make an easy check. Fill the cooling system. Don’t place the cap. Start the engine and check the water through the filler neck. When you see the water clear and constant bubbled in the radiator than you have a head gasket problem.

Greetings from Holland,

Wimor

You can make an easy check. Fill the cooling system. Don’t place the cap. Start the engine and check the water through the filler neck. When you see the water clear and constant bubbled in the radiator than you have a head gasket problem.

You'll need to get the radiator fixed before checking for a failed headgasket 'bubbles' in the water. However you need to get the rad fixed regardless, so to check for bubbles coming into the rad when it is all assembled will hopefully answer that one as 'no' (not 100% guaranteed though)

The radiator could have failed like that due to an age related or quality related problem without anything else being to blame.
On the flip side there could be a few things going on that added to the problem.

It would not hurt to renew the rad cap anyway. The minor is meant to be fairly low pressure, but if someone had used a different cap it could be at much higher pressure.

Whilst it is 'in bits' it is an ideal opportunity to flush out the entire cooling system. (basicaly just run a hose pipe into the engine until it runs out clear, then reverse the direction until clear again, then do it a few more times... And then the same by holding the hse pipe on the endo of the heater hose, and then the other heater hose). The cooling system and heater will work a lot better if they are cleaned out! If the car has been run without a good antifreeze the block will corrode (good antifreeze has corrosion-inhibitors) and the rust swims around in the water until it causes sludge/deposits/blockages.

If the thermostat had stuck, the engine could get very hot causing violent boiling - was there any 'glugging' and 'spitting/fizzing' when it failed? Checking the thermostat is easy (watch it open and close when you heat a pan of water to boiling and cool down afterwards) but removing and refitting the thermostat housing can be a pig of a job. The simpler way to check is to run the car from cold - the top hose should not get hot to start with and after the engine is hot the thermostat should open and the top hose will get hot fairly quickly. It is much harder to spot if the thermostat is struggling to open but when it is hot you should be able to see a nice steady flow from the engine into the radiator (looking through the filler cap) - and when you rev the car up you should see a nice increase in flow into the rad.

Thanks again chaps for your helpful comments...what I need to do is get a replacemnet radiator...and then see if the head gasket is causing a problem...
I've checked out suppliers of re-con radiators...do I need a specific one for sidevalve...My Pitman's Morris minor book makes no mention of the cooling system...!
There is one advertised on ebay...for around £90 plus p&p and they'll give you £25 for the old one ...
Any suggestions...
cheers,
Chris and a 'sad' Duncan

I had a good radiator from ebay for a fiver and another for the guy to post it £10 all in ....sod £90 if you were closer i have a spare .
..

e-minor

fife

do I need a specific one for sidevalve...My Pitman's Morris minor book makes no mention of the cooling system...!

I'm pretty sure MM and SII had the same rad (someone will correct me if I'm wrong). These early radiators have a different header tank, but apart from how it looks to a knowledgable purist they are fully interchangeable.

Series II and MM do NOT have the same one! The MM has a much larger top tank
The series II had the round top tank, the 1000 the smallest of the three, with a more flat top tank. The last two share their cooling block

The side valve engines have a different radiator. The photo is from a side valve radiator from 1952. The overhead valve engines have the hose pipe connection on the other side.




Greetings from Holland,

Wimor

Series II and MM do NOT have the same one!

Ah well - you live and learn
Anyway I was right about the early radiators being different, although not the same as the SII. The SII radiators have different plumbing but can be interchanged with Minor 1000 if you use the later style plumbing parts.

It may well be worth looking for a re-core then you'll have a radiator that works like new.