Need Mk48/15a1 assistance with overheating problem! Any Marine mechanics out there?

[Augdog1964]

Hey all,

We regularly use a Mk48 LVS with a 15a1 recovery trailer for work around the armor barn. However everytime we use the hydraulic boom crane or the rear winch the Mk 48 begins to overheat.

It will peg the temp gauge at 240. We have noticed that the fan never seems to go on to high when this happens as well. However this seems to be just a symptom that makes it worse, not the cause.

Any Marine mechanics have some ideas? Anybody want to come out to Indiana, ride in a tank, and address this issue?

Ideas, thoughts?

Thanks all!

 

[gimpyrobb]

Short term, I'd wire in a manual switch for the high fan setting.

 

[Monkeyboyarmy]

I'm pretty sure that's a hydraulic fan. I didn't realize that it was more than one speed. Sure that HUGE radiator is filled up? And I would also check to see if the gauge is accurate, maybe with a infrared thermometer.

 

[Bandit02]

Any coolant blowing off?

 

[73m819]

Replace the temp. sender, the fan is controlled by Two (at least that is what it looks like on the hyd. system dawning) electric solenoids

 

[Augdog1964]

Hey guys, thanks for the help...

Here is what we know:

1) Yes the radiator is full
2) Yes when it gets hot it has blown juice up and out... nice
3) Hydraulic fluid does not have water in it
4) We have not pulled the hydraulic fluid filter... doing that this weekend... got to pull the manuals.
5) Yes its a hydraulic fan so we can't wire it up for high speed...

Replace the temp. sender, the fan is controlled by Two (at least that is what it looks like on the hyd. system dawning) electric solenoids

Can you reference the diagram for me and the TM? I'll look it up and see where it is... have to go through manuals for the hydraulic filter anyway. Thanks!

Any more help appreciated... we love this vehicle and can't do without it. The crane is so much more useful than the 936.