flushing radiator/block

[Karl kostman]

Good Afternoon folks, I am in need of your opinions concerning having my trucks Radiator and block flushed out please. Last weekend I was driving my Deuce which has an LDT 465 with a C turbo in it down the highway the trip was about 100 miles, it was and outside temp of about 78 degrees and I was running at 2000 RPM, after about 30 miles my temp gauge was sitting at between 200 and 205 degrees, its highest reading ever, if I slowerd down to 1600 to 1700 RPM the temp would just stay at 200 degrees. My thinking is that over the last couple years a bunch of bad stuff in the cooling system must have let loose and was reducing the efficiency of the radiators ability to keep the engine cool and that a complet flushing of the entire system could fix that, the thermostat seems to be working correctly and I have no leaks in the system.What do you think is this a good idea and do you have any precautions I need to tell the truck shop that would do the work? Thanks very much for you input on this.
Sincerely
KK

 

[dittle]

Might check to see if the fins in the radiator are full of stuff, like cottonwood seeds. Its the time of year where that stuff is airborne and can plug up radiators.

 

[Karl kostman]

Radiator is clear of any and all debris, but a good suggestion
KK

 

[blue302stang]

Definitely check to see if the radiator fins are clogged, also check out your coolant level. When is the last time you flushed the system? We flush the cooling system on our trucks at work once a year just for good measure.

 

[Bill W]

Karl
I would first say check/replace the stat and then while its apart pull the bottom rad hose and take a garden hose and flush the block and radiator out from both directions and see what kind of nastys you get out ( also open block drain back by starter ) from there decide if you need to go get the rad dipped at the local radiator shop

 

[gimpyrobb]

If you think it might have crud in it, you could always add a coolant filter too.

 

[cyruscat]

My M35A2 ran about same temps on 90 mile drive home from GL lot.

Decided to flush cooling system shortly afterwards.

Took off bottom hose and removed thermostat. Stuck water hose into thermostat hole on intake manifold with rag to seal it up. Turned hose on high and was shocked to see thick red mud come out of water pump where bottom hose goes on! I then spent half hour flushing block back and forth till only clean water came out.

Radiator flushed pretty clean, just nice green anti-freeze.

Now my truck runs so cool that I had to make radiator cover for winter time!

Enjoy.........

 

[hndrsonj]

Deuces for some reason generate alot of gunk in the cooling system over time. I'd add the filter after a good flush.

 

[M215]

Also consider removing a freeze plug on the block to check how much sediment has turned into cement along the water jacket. I was having some coolant issues on our White halftrack, pulled a freeze plug only to discover a wall of hard sediment. I had flushed the block using the garden hose like mentioned above before. Ended up pulling all the freeze plugs and digging all the sediment out, solved the cooling issue. Freeze plugs are cheap.

 

[Karl kostman]

Thanks very much for all the info I installed a block heater a couple years ago and when I pulled the frost plug out it did not look bad at all inside the block, and things also looked good when I worked on the thermostat, this truck to my knowledge has never had ghe cooling system flushed so I have that scheduled at a CAT dealer for next Wed. should be interesting to see what comes out there! Again thanks you all for you input and I will let you know if this clears up my heating issues!
KK

 

[doghead]

I doubt your Cat dealer has the military tech manuals, but to flush it correctly, you need to remove the T-stat. This is all outlined in the TMs.

I would verify your gauge reading with an IR gun($20) before spending big bucks at a CAT dealer.

 

[Karl kostman]

Good Morning guys well last Monday I had the cooling/block on my Deuce flushed, they did remove that thermostat when they did this and its certainly been a lot better, I drove it the other about 30 miles the OAT was 89 degrees I was running at 2000 RPM and it got up to about 193 degrees max so the flushing certainly helped some. Gimpyrobb could you please explain to me more about the cooling system filter you mentioned earlier in this post, I have never heard of it before it certainly seems to merit some consideration. What is it comprised of, where does it mount and what type of filter is it?
KK

 

[M35A2-AZ]

Karl Kostman, Here is a post about cooling system filter. My post and pic is post #30.

http://www.steelsoldiers.com/deuce/64418-deuce-cooling-system-clean-out.html