Driveshaft roll pin on 1967 Evinrude 6hp

[casioqv]

How important is the "driveshaft roll pin" on a 1967 Evinrude Fisherman 6hp?

When I replaced the water pump impeller on my motor, I had to destructively remove this pin to slide the new impeller down the shaft. I didn't see any purpose for it at the time and couldn't get a replacement- but now the motor won't run well and I have read that this pin is related to maintaining the lower crankcase seal.

The motor has only been run a few minutes without the pin in place. If I take it back apart and add a new pin, should the seal be okay?

[raczekp1]

hi. this pin is very important.
look at diagram :http://epc.brp.com/Index.aspx?lang=E...5-f419770c3de9
this pin is holding seal set, if you run engin without this pin so it can couse that uper cork seal(element no 1 and 3) will slide sideways and will not sael enough.
take out once again main drive shaft, put in this pin, unscerav powerhad(6 bolts, tillt upsaid up endin(place on flywheel and uscreaw 6 bolts holding powerhad to midsection),and asemble all parts in right way. it wil take no more than2 hours

[casioqv]

Is it likely that the seal is undamaged and still in place- so I could just open up the lower unit, install a new pin, and re-insert? Or is the seal probably destroyed from running without the roll pin?

My motor is designed to be able to remove the lower unit and replace the water pump without removing the powerhead, as it has a sort of retaining lip with a slot so the driveshaft and pin can come out of the powerhead, while the seal stays in.

I have a boating trip planned for this weekend, and won't be able to get a new seal before then, but I think I already have a roll pin that will work. I can still use the motor on the trip, if I can just replace the pin- and not remove the powerhead to repair the lower seal.

The engine has probably been ran for ~10 minutes without the roll pin in place.

[raczekp1]

you can try just to insert pin and assemle all parts.thicknes of this pin is 2.65mm, i used to made this pin in homemade way a round end of drill.
lenght of this pin,i dont remember but it shold fit in this slot in midsection
but if you just destroed this seal set by runig engin without this pin, so sooner or later you will get water into cvylinders, or just loos power

[casioqv]

i used to made this pin in homemade way a round end of drill.

Can you clarify this sentence? Are you saying that you cut a small drill bit down to the correct length, for use as a pin?

[raczekp1]

yes.i just cut the round end of drill for right lenght.
i used a drill becouse of its easy to find right thicknes,drills are made in size:2.5, 2.55, 2.60,2.65,.......................... end its easy to decide which size i need.
if you have time you can just order, its cost about 3$

[casioqv]

I found a set of non-stainless roll pins at my local auto parts store. I think I'll just coat it well in waterproof grease, and install. I'll be crossing my fingers that the lower seal is good (not even sure how to tell).

[emckelvy]

That split pin is stainless steel, do not use a carbon steel pin or substitute other than for temporary use, as it'll rust away. If you don't have an OMC dlr nearby, you might try a screw specialty store, they might have something you could use.

The OMC part # for that split pin is 0303261. I just ordered one for a 6hp I'm working on.

I doubt that the seal has been destroyed. The entire spring/seal/brass cup assy is captured between the powerhead and the structure of the exhaust tower and stays in place when you remove the driveshaft.

Without the driveshaft in place, there are no rotating parts up there which could contact the seal. The crankshaft is either flush or recessed to the bottom of the powerhead.

With the lower unit removed, you should be able to look up there with a strong lite and verify everything is in place. If it's slightly off-center, just get a wooden dowel or other suitable long object and re-center the parts. Be sure to grease up the driveshaft splines and a bit of grease on the split pin, before reinstalling the lower unit.

And as you are aware of, you have to have the pin aligned with the notches in the center section in order to remove/reinstall the lower unit. Once the split pin is past the notches and engages the spring/seal assy, you can turn the flywheel to mate-up driveshaft to crankshaft.

IMHO I wouldn't run the motor until this is fixed. The carbon seal keeps water from being sucked into the motor. And also seals the air/fuel mix for the bottom cylinder. It may not idle very well without that seal in place. And if you're running in salt, you'll certainly do some damage without the seal working properly.

HTH...........ed

[F_R]

What emc just said is good.

It's too late now, but you didn't have to remove that pin to work on the water pump. All you had to do was pull the shaft out of the lower unit and take the pump parts off/on the bottom end of the shaft.

[casioqv]

Thanks! I'll install a plain steel roll pin or drill bit for now, and replace it with a stainless one when I get a chance.

[raczekp1]

hi.
i bought one 6hp without this rol pin, and o ring was destroyed, and cork seal looked like egg instead of round.engin was smoking too much and take too mauch petrol.
i did this pin using drill, becouse it's not easy for me to order orginal pin .i used drill proof for rust and its working.

[casioqv]

It looked like everything was in place and lined up, so I installed a 3/4" regular steel roll pin and reassembled. I'll add a stainless one sometime in the future.

The first time I had the lower unit off took me weeks, because the stainless bolts were corroded in, and sheared off. Now I can do it in minutes- since I know how it goes together, and the bolts are all coated in Tef-gel galvanic corrosion inhibitor.

Evinrude should have known better than to install stainless bolts into an aluminum housing without coating them with a corrosion inhibitor. Perhaps Tef-gel and similar products didn't exist yet in the 60s.