M923A1 radiator leaking drivers side.

[Carlo]

Last Sunday I had my A1 and A2 out on a soft air tournament rental. The A1 started leaking just a little bit. The leak is coming from the tray below the radiator. I can see no direct leaks from the radiator. The upper and lower hoses are dry.
One thing strange is it will only leak when running and less than a minute after shutting off the leak stops. This happens even with the radiator cold or hot. I would think that if the radiator had a hole it would leak even with the motor off but this leak stops shortly after the motor is shut off and as soon as the motor is running ( seconds after) it begins leaking. It sounds like a water pump failure but under the pump it's dry plus the leak comes from under the radiator.
I have not had time to remove the shroud. That will be done this week. Maybe With this shroud off I can see more.
Has this happened to anyone?
thanks

 

[Hoefler]

I had a M35a3 with blown head gasket. It pressurized my coolant system. Check for bubbles with rad cap while running.
pete

 

[Carlo]

Thanks Pete. No bubbles with the cap of motor running. I hope to remove the shroud on the radiator so I can see the drivers side corner. Maybe there is a tube broken.
Thanks again Pete.

 

[Artisan]

Is the radiator cap releasing at proper pressure or is it inop?
Test it or throw a new on perhaps as a start.

I think the TM's give a blow by blow tutorial on how
to disassemble and reassemble those monster radiators.

If it is any help there is a HUGE radiator testing tank for sale
at the GL facility in Fontana. If anyone wins it I got dibs on
the anvil inside it!

 

[Coffey1]

The bolts that hold the side caps will work loose and it will leak then quit. Check all those nuts and bolts on both sides.

 

[Carlo]

The cap is new for the old one was releasing to easy. With the truck running and removing the cap there is the normal pressure release. I'm afraid it's a tube behind the fan shroud. I must get the shroud off and look in the bottom lower corner. I can only see the water dripping from a tray below the radiator. As the day progressed the leak did also.

 

[Carlo]

The bolts that hold the side caps will work loose and it will leak then quit. Check all those nuts and bolts on both sides.

Thanks Coffey1. This was one of my concerns. Man it would be nice if that was all it is to fix! The radiator is new as the motor too for the truck was recently rebuild by the army.
Thanks again.

 

[Coffey1]

Carlo there are about 50 bolts down the sides of the radiator that will loosen up over time from heating up and then cooling down.
A bunch of mine were loose and radiator was leaking tightened those bolts stopped my leak.

 

[Carlo]

Thanks for the heads up Coffey. I checked the bolts and some were a little lose but not enough to cause it to leak this much. I had some time today and got the flash light between the shroud and the radiator and can see some coloration on the fins but not running water. I must remove the shroud but it's going to be fun. I think it might be easier just to remove the radiator. At this point I have little choice. Its got to be a hole.

 

[MyothersanM1]

Different truck, but my M818 radiator leaked from where the top tank plate soldered to the core when the system pressurized. Coolant would trickle down when running and I'd get that distinctive maple syrup smell. The coolant would then pool in front crossmember and drip from the hole in the crossmember when I stopped. I know the M939 series trucks radiators orient horizontally, but the problem will rear its ugly head in more the same fashion. If it is leaking to the extreme left/driver's side then check that area. Not to rain on your parade, but I ended up re-coring the radiator.

 

[DJones]

The bolts that hold the side caps will work loose and it will leak then quit. Check all those nuts and bolts on both sides.

Mine is leaking from drivers side end cap. I tightened the bolts but still leaks a little until it heats up and it stops the leak. I plan on pulling mine and having it gone thru at a radiator shop.

 

[Carlo]

I got everything bolted up in July. There was on rod leaking. I welded it up and ran a pressure test. All ok.

Sorry for the late update.

 

[Scar59]

Carlo,
I spy the '08 Crown Vic in the back of the shop. Is it a true Ford P71 (Police Intercepter). I cloned an '02. Real nice cars.
JC

 

[Carlo]

Carlo,
I spy the '08 Crown Vic in the back of the shop. Is it a true Ford P71 (Police Intercepter). I cloned an '02. Real nice cars.
JC

Yes it is but it's a MP/Staff car version. They are used very rare here. I've only seen a few in Europe by the US military.
Sorry the photo uploaded upside down.

 

[Scar59]

It looks faster up side down. Nice car, keep that one, no longer produced by Ford.

 

[Carlo]

It looks faster up side down. Nice car, keep that one, no longer produced by Ford.

For only a 4.6 liter motor and very heavy car it's surprisingly fast. It will lay down two very long black tires patches with little effort. It's got less than 4500 miles. I think that's pretty low for 2008.

 

[Scar59]

Very low for mileage, yes and very fast. The computer program (tune) can be altered and make that 4.6 hum. My 2002 has a reprogramed tune and turns around 350hp. It does run on 93 octane though. Not driven everyday. Keep her safe.