149 diff cover torque

[Roma4593]

Hey there,

I recently acquired my first 149 and I am really loving it. Its a real cherry (to me) but I've been going through the stepwise process of refreshing it and changed out and flushed the hydraulic fluid recently which I am glad I did- it was definitely not spec. I am struggling a bit with a very small leak from the rear diff cover and I am scared to over torque the bolts. Initially I had an off-brand gasket that leaked like a sieve. I replaced the gasket (and sadly all the hytran) with a cub factory gasket with copper gasket sealer and I am still having a tiny leak maybe a 1/4 tsp per 24 hrs. I've been stepping the torque on the cover and im at 30ft/lbs- hopefully I haven't overdone it but I am scared to go up any higher. The book says 33-37ft/lbs for type 5 bolts from what i can tell but ive seen so much mixed information about the diff cover bolt torque. specifically. Do I just need to man up and wrench it down more? Is there a chance this could slow down (or get worse)? Does the torque change with a sleeve hitch?


Thank you all kindly for such a great forum and I appreciate any help!

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[ol'George]

Take the cover back off (saving the fluid) and clean the cover.
Then open your vice about 1-1/2" and lay your cover over the opening inside up
and using about a #2-3 hammer whack each bolt hole making the cover just a bit indented around each bolt hole, not much just a bit.
The cover has become puckered in from, previous attempts at over tightening it.
Now when you tighten the bolts, the cover will pull flat.

I've been doing this on sheet metal oil pans for over 6 decades as well as covers that have become puckered.

I have also found that if you completly degrease the cast iron surface,as well as the cover,then you can forget the gasket and use silly cone or honda bond/yama bond #4 crankcase sealer.
Its grey snot that holds up better than silly cone and is more flexable.
But as when using any sealer, the surfaces have to be completly clean, as any oil
will prevent sealing.

[green407]

When you say "with copper gasket sealer" are you talking a silicone based sealant?

If it is a silicone based sealant, you'll most likely have to re-seal it again.
you need to make sure all of the mating surfaces are spotless and dry.

The book says 33-37 ft/lbs, so that's what you should do.

The torque doesn't change with the sleeve hitch, just the length of the bolt.

[ironman]

Like ol'George saiz. Throw away that paper gasket and use this.
Lay a 1/4" bead, put the cover on, tighten bolts finger tight.
Wait an hour or more, then torque lightly.

[Roma4593]

Thank you guys!

[Roma4593]

Originally Posted by ironman

Like ol'George saiz. Throw away that paper gasket and use this.
Lay a 1/4" bead, put the cover on, tighten bolts finger tight.
Wait an hour or more, then torque lightly.

I carefully flattened the plate dimples exactly as George described and went with the permatex. Only 15lbs of torque and the bolts were snug. Everything is bone dry with no leaks- thank you guys for the replies.