1967 Evinrude 6hp drive shaft reinsertion problems

[cajuncook1]

I am having problems reinserting the drive shaft into the exhaust housing. Removed the lower unit to replace the water pump and now I can't get it back in. It would seem that would side back in without much difficulty. The drive shaft plate under the crankshaft seal gasket is getting stuck midway up the tube. Is there a trick to this or do I need renew my shortbus pass?

There is a diagram supplied (borrowed the machinist's diagram)

All of the drive shaft seal parts are original except the drive shaft/crankshaft seal/gasket (1st part ) and the o ring (3rd part).


Any help greatly appreciated!

cajuncook1

[BigB9000]

up near the top of the mid section, there is a little slanted cross bracket that will throw everything off. while sliding it up, rub the shaft up against the wall of the mid section, all the way to the top.

[bktheking]

That looks like the same setup as my 55 7.5, in which I had to remove the powerhead to disconnect the shift rod to get the lower off. That whole setup becomes a non issue as I can put it back together from the top. I'm not sure how that model goes back???

[F_R]

That looks like the same setup as my 55 7.5, in which I had to remove the powerhead to disconnect the shift rod to get the lower off. That whole setup becomes a non issue as I can put it back together from the top. I'm not sure how that model goes back???

Something is wrong here. That stuff should not have come down with the shaft. Are you sure that you have a 1967 6hp??? Are you sure it isn't a 5hp??

It helps to know what we are working on.

[BigB9000]

I read it all wrong.

anyway, all of those parts are located under the powerhead. they do not come out without removal of the powerhead.





See the prop hole? no way for the springs and whatnot to fall out

[cajuncook1]

Something is wrong here. That stuff should not have come down with the shaft. Are you sure that you have a 1967 6hp??? Are you sure it isn't a 5hp??

It helps to know what we are working on.

Yes it definitely is a 1967 6hp evinrude (6702S-E14920). I must give you a little more history about this situation.

- bought the motor 1967 6hp evinrude (6702S-E14920) from a guy for the gearcase, lower unit, throttle assembly, midsection and hood.(It was a complete motor but the powerhead was in poor shape)

- I have good running 1969 complete powerhead that I bolted on after I reassembled the motor.(90LB in #1 cylinder and 92#lb in 2nd cylinder.)

- I took the 1967 6hp evinrude (6702S-E14920) apart to replace the broken shift lever and replace the fractured steering bracket. So when the exhaust tube/midsection and lower unit was off, I disconnected the lower gearcase, because I knew I was going to have to change the waterpump and seals.*****I think that is where I made my mistake and I think that it what your eluding to FR**** The drive shaft plate under the crankshaft seal gasket came down with the driveshaft because I had the old powerhead off and removed the exhaust body and lower unit (after removing the motor mounts).

So, how do I resolve my situation? I have a feeling I'm going to have to remove the powerhead.

cajuncook1

[bktheking]

Yup, powerhead has to come off, I feel for ya brother

[BigB9000]

yeah remove it again.

When I remove mine, i remove the lower unit, then remove the power head.

When reinstalling, replace the lower unit, and put the parts back in, the drive shaft will help hold it all together.

when I first did my engine, I installed it with the lower off, it was a pain in the butt to get everything back together. the second time, with the lower on, was much easier.

[bktheking]

Oh and I almost forgot...................




It's ok, I got mine with my DVA 22uf cap instructions, duh.

[cajuncook1]

yeah remove it again.

When I remove mine, i remove the lower unit, then remove the power head.

When reinstalling, replace the lower unit, and put the parts back in, the drive shaft will help hold it all together.

when I first did my engine, I installed it with the lower off, it was a pain in the butt to get everything back together. the second time, with the lower on, was much easier.

So do I remove all the seal assembly parts listed in the diagram and then insert the drive shaft and bolt it on? Then will I remove the powerhead and then am I to, in order, slide the seal assembly parts from the top with the powerhead off.

-Can you tell me which parts I will be reinserting from the top and which from the bottom?

Oh will I have to remove the powerhead everytime I change the waterpump?

Thanks for the quick replies gentlemen!

cajuncook1

[cajuncook1]

Oh and I almost forgot...................




It's ok, I got mine with my DVA 22uf cap instructions, duh.

LOL!!!! It's fun learning to repair these old but good motors!!!

[bktheking]

Here's how it works:

On the top part of the driveshaft there should be a roll pin. That pin fits up through the slot in housing the powerhead sits on (I guess the midsection)and pushes up on the bottom cup which in turn pushes the entire spring assembly upwards to create a positive seal on the bottom of the powerhead. The way it is designed to work- when you go to drop the lower unit you turn the shaft until the pin lines up with the space allowed in the pic of the midsection that was posted, the lower will then drop. The remaining parts from that spring assembly remain under the powerhead held in place by the metal lip seen in the pic. I wish my 7.5 was like this. If it's the same setup as mine, F_R has mentioned to replace the cork seal at the very top, so now is the time to do it. I'm sure if i'm wrong he will correct me on anything I just stated.


PS- if I were you, pull the powerhead, replace the spring and seal assembly , bolt the powerhead back on and put the lower back on.

[cajuncook1]

Here's how it works:

On the top part of the driveshaft there should be a roll pin. That pin fits up through the slot in housing the powerhead sits on (I guess the midsection)and pushes up on the bottom cup which in turn pushes the entire spring assembly upwards to create a positive seal on the bottom of the powerhead. The way it is designed to work- when you go to drop the lower unit you turn the shaft until the pin lines up with the space allowed in the pic of the midsection that was posted, the lower will then drop. The remaining parts from that spring assembly remain under the powerhead held in place by the metal lip seen in the pic. I wish my 7.5 was like this. If it's the same setup as mine, F_R has mentioned to replace the cork seal at the very top, so now is the time to do it. I'm sure if i'm wrong he will correct me on anything I just stated.


PS- if I were you, pull the powerhead, replace the spring and seal assembly , bolt the powerhead back on and put the lower back on.

Thanks, will probably get to it Thursday noon or Friday morning...I hope

cajuncook1

[BigB9000]

you'll need a new gasket. this really is a 10 minute job. assuming you have no broken or striped bolts.

[F_R]

1. Pull the powerhead

2. Install the lower unit to the midsection.

3. Now stack the seal parts on the drive shaft. Yes, use a new 303355 gasket and 303347 o-ring on the seal assembly. You DON"T want any leakage there.

4. Now put the powerhead back on.

In the future, it is only necessary to rotate the flywheel till the pin lines up with the slot, then drop the lower unit down. The seal parts will be retained in place below the powerhead.

[1946Zephyr]

so, is this true on all the 6's? I know it is on my 74 model.

[cajuncook1]

Thanks very much gentlemen!!!!! Will let y'all know how it turns out!!

Cajuncook1

[BigB9000]

I have been debating to myself weather of not that upper pin actually does anything.

if you think about, the pin will force the Seal spring Washer to spin, along with the spring, lower seal, upper seal, Drive shaft to c'case washer & gasket. probably not good.

I dont think that the pin even goes up in there. I'll test my theory out in the morning.



cajuncook1 - If you need step by step pictures on how to do this, let me know.

[rodbolt]

trust us, you NEED that pin or the lower crank seal simply wont.
motor will idle nasty.
usually I shear that pin when trying to remove the gearcase.
but ALWAYS replace the pin if broken or missing before reinstalling the lower.
if you look at the spring cup you will note it has two indentions just for that roll pin.
reread some of the previous posts and it was explained how and why the seal works.

[1946Zephyr]

That pin presses the powerhead seal firmly to the bottom of the crank. Everything together spins all at the same time, but the pin just compresses the spring in the assembly.

[jay_merrill]

I have been debating to myself weather of not that upper pin actually does anything.

if you think about, the pin will force the Seal spring Washer to spin, along with the spring, lower seal, upper seal, Drive shaft to c'case washer & gasket. probably not good.

I dont think that the pin even goes up in there. I'll test my theory out in the morning.

Don't waste your time trying to figure out if it "goes up in there" - if the motor is reassembled properly, it does. You should also not waste your time wondering if the pin is necessary - it is. The point of the seal assembly, including the pin, is to keep water/moisture out of the powerhead. I have a frozen 6hp powerhead sitting in my shop right now - the victim of a missing seal assembly.

I just finished a water pump job on a 6hp of that vintage, the night before last. I've done a bunch of them and find the process to be pretty easy, if you do it correctly. The trick to lining the pin up with the slot in the upper end of the midsection, is to put the motor in gear and once the top of the drive shaft is in place, turn the prop (plug wires off and pulled away from he plugs, please!) so that the shaft turns clockwise, as viewed from the top. Do not turn counterclockwise even a little - if you do, the impeller blades will try to reverse or will reverse! Do this slowly, a bit at a time and try pushing the gear box up each time you stop. If you miss the slot, keep going clockwise, until you are properly lined up.

Like most repair jobs, this process is just a matter of learning the proper way to do things. Once you do, its not hard.



°¿°

[F_R]

so, is this true on all the 6's? I know it is on my 74 model.

I'm pretty sure it is. There might be an exception on the very earliest ones, but I don't think so.

[cajuncook1]

1. Pull the powerhead

2. Install the lower unit to the midsection.

3. Now stack the seal parts on the drive shaft. Yes, use a new 303355 gasket and 303347 o-ring on the seal assembly. You DON"T want any leakage there.

4. Now put the powerhead back on.

In the future, it is only necessary to rotate the flywheel till the pin lines up with the slot, then drop the lower unit down. The seal parts will be retained in place below the powerhead.

Will follow your instructions to the letter. Will update when completed. Might be a few days. Believe it or not it is snowing pretty good out here in Texas!!! The kids have a snow day because school is out. Hopefully Monday or Tuesday I will have a report.

Thanks everyone for the time and instructions!!!!

cajuncook1

[bktheking]

Just wait till the military arrives to dig you out, we take shots at Torontonians for that little mishap a few years ago, here is Ottawa we laugh at snow!

[F_R]

To sum this all up, the seal keeps water out of the crankcase. If water gets in there it will cause slow damage to the bearings and someday it will throw a rod. Trouble is, then somebody will look at it and proclaim that it was run on the wrong oil. So the real problem never gets widely known.

If you assemble it all correctly, the cup, spring, and carbon seal rotate. The plate does not rotate. Sealing takes place by the ground surface of the carbon rotating on the flat plate. The o-ring completes the job by sealing the whole assembly to the drive shaft.

If you do it CORRECTLY, you will use a new gasket on the plate, and you will glue the gasket to the plate. Friction of the gasket against the crankcase and being glued to the plate keeps the plate from rotating.

The last five 5.5 & 7.5hp motors I've worked on all had defective and/or incorrectly installed seals. One of them threw a rod, one was within one start-up of throwing it, and the others were all damaged. Guys, these fine old motors are all quickly being destroyed by people working on them and not doing it correctly.