Cat 3208 NA Front and Rear Seal Replacement

[Scout_1969]

Need some advice about front and rear seals:

Background:

I am swapping out motors (posted in another thread https://www.heavyequipmentforums.co...n-MT653-Auto&highlight=replace+rear+main+seal).

The donor motor has 51K miles and is an original 1985. Seals don't appear to be leaking. I have the clutch out and the bell housing is dry.

I may have to swap bell housing due to auto trans. vs manual, so the seal may need to be replaced anyway.

Some forums for cars and trucks say that you have a 50/50 chance of a leak with a new seal and has me a little concerned.

I have a CAT manual and they show specific tools that are pricey.

Questions/thoughts:

Should I replace them?

Aftermarket or OEM seals?

Can I use commons items for tools, like screws to remove and a piece of pipe to install?

Any tips would be welcome.

 

[crane operator]

We did a rear seal in my 3208t this summer, after the rear housing cracked. The seal install tool was horribly expensive from cat, but they let me use theirs. It's kind of a press/screw on seal tool, (looks like a seal driver with a threaded center bolt) and a guy could make one without too much trouble, if he had one to copy.


The rear housing is aluminum, and mine was cracked from loose transmission bolts, which took out the rear housing seal. It also had 2 broken bolts from the housing to the block (the guys were nice enough to let me drill them out when they found those, at least if I ruined something, I couldn't blame them). I paid dearly for the seals and gaskets from CAT, but who wants to drop trans, hyd pumps (in a crane), and do it again because you bought cheap seals? If I missed 1 crane job, it could cost me $1,000.

I've read some that you're supposed to do some special measuring and fitting when reinstalling the rear housing (that its precisely inline/square with output shaft), but we just bolted it up. Which, with my luck, will mean that I get to drop trans, hyd pumps, and lose $1,000 on a crane job, because I didn't, and it will crack the rear housing and take out the rear gasket, because it wasn't perfectly aligned. At least I'll be familiar with the process.

So, to answer your question, I used CAT seals, the $600 install tool (which I got to borrow), I wouldn't try driving it on with a piece of pipe, and knock on wood, it doesn't leak (at least not from that spot on the motor, its not perfect).

 

[Scout_1969]

CO- Thanks for the reply.

It appears that I won't have to change the bellhousing now that I have the motors and transmissions out. There's an adapter ring for the auto trans. that bolts on to give a little more depth for the torque converter.

The line-up procedure I was told in another thread, isn't required if the flex plate to torque converter was marked to orient it the same as it was removed. The manual says something about a dial indicator to set up (tighten) the flywheel or flex plate.

 

[Nige]

If you can establish a good relationship with your local dealer you may be able to borrow the tooling, especially if you buy the new seal(s) from them. The tooling is expensive and you can't justify buying your own. I would certainly change the rear seal while you have the engine out, and if you do one you might as well do both of them.

 

[Catman4]

If engine is not installed suggest take engine to closest Cat / Teps dealer or independent repairer who has the tooling.
If flywheel and front pulley are already removed the new seals would be installed for one hours labour charge.
The special tooling is definetly required for the rear seal as it is a seal group ( seal and wear sleeve) and must be installed as a group.
Also check the seal track area on crank pulley for front seal as a thin wall wear sleeve is often installed to restore this area.

 

[d9gdon]

The best way to change the front and rear main seals on a 3208 Cat is to swap the complete assembly for something that will fit in that spot, like a 5.9 Cummins or a nice JD , Perkins, Rolls Royce, International, Mercedes, Mitsubishi, Oliver, Mineappolis Moline, Case, Detroit, AC, Massey Ferguson, Ford, Buda, Komatsu, Mack, Rumley Oil Pull, Fiat Allis, Allison, Rousch, Murphy, British Leyland, or 292 Chevy engine.

...and I'm only being serious. You will come out ahead.

 

[Scout_1969]

Nige- Thats what I ended up doing, they are good people.

C4- In hind sight that may have been a better option, by the time I ran and borrowed a big puller, worked through the instructions, removed the steel sleeve etc. Although now I have the experience for what that's worth.

D9- Others have suggested a swap- but doing it myself for my farm/off road use just seemed to costly and time consuming. Besides, I found a replacement with 51k miles in good condition. I think if I were in a business where time is money etc., another type engine might be worthwhile, but then again, with the condition of the cab/dump body and just age. Then again I probably would be better off removing the steering wheel and putting another truck under it.

Thanks for the replies.