Gear Case Sealant

[Casey Lynn]

quote wannabe outboard guy:

Pappy and Chris,
When you do your gear cases, do you use OEM spaghetti seals, or aftermarket (Sierra, NY Marine’s, or other). Is any one seal better then another in your experience?

I do not use aftermarket parts. Have never been dis-satisfied this way! I cut from a roll of p/n 309044 seal. That part number is from memory so beware and check it before ordering!

[johnny-infl]

I guess my pill cutter is too "upscale" – – – it has a guard to keep little fingers
out of it – – plus, a plastic piece to hold the pill still and centered ….. so that does not work.
Edit: I drilled a 1/8" hole into each side, but, even then, it is the same "chop"
style of cut I have been doing with the X-Acto blade and single edge blade.
And, the cutter blade does not bottom out, it is like 1/32" from touching the bottom.
so that does not work for me.
The "roll-n-cut" works for me.

I did learn one thing while doing this – – –
the red or orange seal is Food Grade for mixers, etc.
the black is not food grade, mechanical only, away from food processing equipment.

so, I guess your gear oil is safe from outside contaminants ?

[fleetwin]

It seems doubtful that the oring seals are at fault, even with no sealer, unless there is a defect in the housing allowing water to leak by the orings.
More likely one of the seals, or grooved shafts, or perhaps a shift rod seal…Don’t know how those are set up on the Chryslers.
Once you have it reassembled, you should pressure test the gearcase to ensure the problem is solved.

[chris-p]

While being important that the end is cut square, the main mistake made is the length of the spaghetti seal.

Always push it to the outer edge of the groove, so that it cannot possibly shrink any more, leaving a gap where it abuts the prop shaft housing.

After pushing it towards the outer edge, you want about a 1/16" overhang. If there is too much overhang, the seal will buckle when you try to install the skeg half. then there will be 847 all over the place, and you will have to start all over. IF there is not enough overhang, there will be a gap and you could get water in. The trick is just enough.

[bill-russell]

On those Chrysler and force gear cases,you need to check the condition of the driveshaft below the pump @ the upper bushing. If the shaft is galled up,then the bushing will be bad. You will have a hard time ever sealing that case.They will often withstand a pressure test,but because of driveshaft flex,will leak when under power.Have seen this many times with cases run with water in them. They can be fixed, but that’s another story. Other than that condition, those cases are easy to seal. Bill

[johnny-infl]

Good points Bill

I like to have never got that little shifter foot thing in correctly on the end of the shift rod to the end of the prop shaft.
oh well, the next one will be easier – oh wait – there will NOT be another one !! (Force, anyway).
Took me almost 4 hours to replace 4 seals – I should be paid by the hour ! LOL
anyway – I am confident I am very confident is tight with no leaks. Will torque it tomorrow and pressure test it.
then, put it on C/L FOR SALE !
Hopefully, I get my Crestliner back Sunday from my brother and I will put my RD-19 on it play with that for awhile.

fun fun FUN !

.

[johnyrude200]

+1 to all comments. Cutting the seal is easy. Hold with 1 hand on a flat surface, then use a box cutter and draw the blade back toward you making sure it’s square. Even if your cut is somewhat diagonal, leaving a little extra at each end will just get waffled in once you tighten down the gearcase screws.

If you can’t figure out where the water is getting in through pressurize the gearcase and submerge in water. Wherever the bubbles are coming out of, that’s your leak. Vacuum testing may be in order too. Repeat the process until no bubbles/drop in pressure/vacuum.

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