F60L Cab 12 truck

[Shane]

Hi all.

Would just like to know what the best thing is to flush out the diff. I am not going to take it apart so i was hoping either diesel or thin oil would work the best. Also is there any danger taking the booster apart?

[Phil Waterman]

Hi Shane

Concerning flushing the differential are you going to remove it from the axle or try and do it in place?

Trying to flush in the housing has some issues as you probably guessed of loosening dirt and gunk up but with out really not getting it out of the housing and having work into the axle bearings. When I first restored my HUP and C60S years ago I flushed the differentials by draining the gear lube and refilling with a 50/50 mixture of kero and gear lube and then drove the thing up and down my drive I think all this did was flush out the old lube because it really didn't come out with much stuff.

On my C60L and recent HUP overhaul I pulled the differential units and really cleaned them. One thing I can say about trying to clean the housing and the gear units is the only way to really get them clean is with real hot water or steam. I used Gunk to really loosen up the old gear lube, then washed them with 170F water.

Concerning dis-assembly of the brake booster, do you have the manual? Don't try without it and pay particular attention to the actual valve assemble very easy to damage. With care you can take these apart clean and reassemble without problem. Checking them on the bench for leaks is much much easier than installing in the truck. Look/listen particularly for leaks around the piston barrel.

Cheers Phil

[Shane]

Hi Phil
Thanks for your advice mate i have just put the wheels and axels back on so i wont be taking the diff apart this time. I have drained the diff oil and you could stand a stick up in it however not to much grit. So just boil water and pour it into the diff? Do i have the bottom plug in then let it drain or allow the water to run right through? I dont have a manual for the booster im thinking i should send it away to get fixed, Hugh Davies has a mate who sent us the booster i dont know if he is part of the MLU clan hope he is so i can thank him. Thanks again Phil

[Phil Waterman]

Hi Shane

But if the fluid you drained out didn't seem to have much in the way of dirt, grit or water. I think I might just go with Kero spin the wheels one at a time to work the diff gears and turn the drive shaft. Then just drain it and see what the drain looks like if it is just dark fluid with no chunks or grit then skip the water. Let it drain for a long time then just refill with correct gear lube and call it good. Just keep an I on the color and texture when you check the lube level.

If the gears are well coated in old lube you might consider waiting on this project until the truck is ready to drive as driving for a couple of hours is probably the best way to get all the moisture out of the differential.

When I did it sprayed in the degreaser mix of Gunk and Kero turned one wheel and the drive shaft to get it spread around then ran hot water through it with the drain out and turning the wheels both sides and and the drive shaft until the case felt warm then took a plumbing fitting to hitch an old hose type hair dryer up and just let it blow through the case for a couple of hours to really dry the insides out turning a wheel of the drive shaft every now and then.

Refilled the case with new rear axle lube per the manual. Then drive the thing around.

The CMP differentials seem to run cooler than some of the US Military Stuff. My CMPs after an hour driving average only 30-40F over the air temp. So air temp of 21C will get you 41 - 53 C which takes awhile to drive out any moisture.

Cheers Phil

[Tony Wheeler]

Originally Posted by Phil Waterman

hitch an old hose type hair dryer up and just let it blow through the case for a couple of hours to really dry the insides out

Best way to remove moisture from internals is to flush with methylated spirits, ie. alcohol. Water and alcohol are miscible (eg. beer, wine, spirits) so the metho carries away every molecule of moisture immediately, leaving a thin film of alcohol which quickly evaporates. Advantage of this method is speed, which is not only convenient, but also eliminates corrosion, which occurs rapidly on bare metal in the presence of water vapour, esp. if hot/warm (no big deal in a diff, but potentially important with very small components, esp. bearing surfaces). You could fill the diff with metho ($10-$15 for 5 litres at the supermarket) then drain and fill with oil immediately. Any remaining alcohol will soon evaporate through the breather.

Metho is quite useful stuff for eradicating moisture, eg. from brake systems after long disuse, or fuel systems that have accumulated water - usually through condensation inside non-airtight fuel tanks. Normally it sits on the bottom of the tank and eventually gets sucked into the carby (after filling up the fuel filter bowl if fitted), but a bottle of metho poured into the tank will mix the water with the fuel and allow it to pass through unnoticed. You can demonstrate this effect by putting some petrol and water in a glass, then adding some metho and stirring - the two separate layers of petrol and water disappear. If nothing else it's a neat party trick!

[Shane]

Cheers Tony. I have a few other questions if you or others can help.

Do the seats bolt onto the cab plate or is there a piece of wood between the seat and cab plate?(mine had wood between)

Also i have seen the fuel tanks on several pictures of the cab 12 that show the fuel caps close to the rear of the cab and other pictures of the fuel caps facing away from the cab. Is there a right way or does it not matter.

I have two seats that not sure which one is correct for my truck so here are the pictures.

20140121_150652a.jpg 20140121_150932a.jpg

Here is a picture of her so far

20140204_171745a.jpg

I will be going to Corowa next month so if any one else is going and has Cab 12 items for sale im in need of a few items. You know the small things... Spare wheel carrier, drivers door, engine cover that sort of thing.

[Shane]

Well it has slowed down my cab12 project but what the heck its faster, lighter, cheaper..............But all in good time one will carry the other

http://www.youtube.com/watch?v=RJLle81Xq2Y