Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Radiator leaking

It is possible to repair a plastic tanked rad.
The tanks are usually crimped to the end plate of the core, usually with a seal to ensure no leaks.
The cause of the failures could be vibration causing a fatigue type failure at weak areas. The pipes on the tank are connected to hoses that can hold them firmly enough to causie enough stress so the cracks to occur.
A Morgan does suffer more vibration than other cars(?).


As for cracking Al rads..... No need to wait for the noggin...get a drink, sit back......
The cracks will start from a stress point...these can be at joints, welds,bends etc.
Again vibration is a likely cause.
My Al rad had a weld failure where the top mounting bracket weld to the tank was cracking. The crack started at one end of the weld and was slowly extending through the weld.
It was due to poor line up of the bracket to the cross member causing side strain and a pull on the weld. Vibration will have then resulted in stress at the end of the weld.
The bracket was removed by letting the crack go most of the way along allowing easy separation.
Thorough cleaning and JB Weld stuck it back, the bolt hole was elongated to remove the side stress and a padded bracket added to assist steadying the tank. A new bobbin was also used.
No signs of problems over about 3k miles so far.

The Al alloy used for the rads is unlikely to be affected by heating to the temps of the coolant...poor welds are more likely causes or bad joints. Residual stresses can be left in welds unless annealed and vibrations aggravate these.
Blocks and heads get localized temps well in excess of a rad and this can lead to cracking, annealing can reduce this.
Different Al alloys are used for them but nothing exotic.
Blocks/ heads use casting Al alloy whilst rads use wrought alloys.
Hope that helps!

Changed mine when a small pinhead leak appeared in a core pipe,35 year old, and think original. Replaced last year with copper brass old style. Another 35 years should do me OK.

Due to a radiator leak Matt-Mog was out of use.



The leak was on top of the radiator and could not access it without removing the cowl.



Seems easier to me than disassembling the radiator. No need to deflate.



Found in this thread (Page 2) something about removing the nipple and went for it.





It came out very easily.
But not as it should be! Hardly used force or pressure.



What now?
I found out that this is not a Morgan part and couldn't find a replacement.
A new radiator? Maybe,
But; I'm an old-school engineer “why replace it if it can be repaired"

let's go for it.
First find the right O-ring. The number of different sizes is infinite. Had to do 2 shops for the right one.

Put it back in and it fit perfectly. But now he has to stay in place.
My first thought was to stick something between the top bracket and the nipple.
But because they can move in relation to each other, not a good idea. Then I saw the mounting screw behind the nipple!
Made a bracket (squared?) that presses on the nipple.



Did a test ride without cowl and bonnet. Everything okay all reassembled and in the meantime I already have a few 100 Km without any problem.





Cost 50 cents ant lots of fun. If needed can still replace, now know where to start.

Good work!

PART FOUND



After a tip from Gambalunga and rereading this thread, I thought this would be a good tip for someone with the same problem.
Peter has the same problem with the radiator.
He went looking for this part (that I couldn't find) and found the answer in Ukraine of all places.
Apparently it is also used by BMW and Mercedes.

Here's what Peter found.

Quote

BMW 7 series
A bit of Mercedes in my car or a small radiator leak from the return connector
calypso Was 5 hours ago
I drive a BMW 5 series Gran Turismo (BMW 7 series before that)
Kiev, Ukraine

I have noticed some fogging of the antifreeze on the top of the radiator, where the air bleed hose comes to the return connector. Was observed only when cold. Seems like the o-ring has dried out and is leaking slightly when the car is cold.
Trying to gently pull it out to replace the ring I eventually broke one of the three anchors, and then I got a surprise. BMW is like that, it doesn't come as an individual part, you have to buy the radiator assembly...
Good thing other manufacturers are smarter, and I found some info on the internet that this part is perfect for a Mercedes. I decided to use it because it can be delivered the next day.

Part pictured: A0005000894. BMW 7 series (E38)
Parts pictured: A0005000894

Mercedes A 000 500 08 94
Hella 8MY 376 743-321
BMW 7 series (E38)
You can clearly see how the O-ring is shrunken

Price: 4 € Mileage: 393,000 km
Plastic outlet.
A0005000894
MERCEDES
Cooling system connector
8MY376743321
HELLA
12 Oct 2017
Tags: breakage
2
Previous Expansion tank


The only problem is that they charge more for the delivery than what the piece costs.
As there is a MB dealer in the neighboring town, I went there to ask about this article no..
They didn't have it in stock but I could pick it up the next day for 10€ ex Vat.
ordered two "for the some price as one delivered" to have a spare or to help someone in need.

Well done

Very useful information

So you see, buying online is not always the best solution.