MC-1 Drive Dog failure?

[ratdude747]

Got the drive apart... Funny, the part of the yoke that rides on the seal looks fine...



Unless that rusty groove under the shine is the surface in question. Sleeve it?

The gears have some very light pitting:



Nothing massive... But still ok to use? The bearings feel great... Smooth as silk.

 

[ratdude747]

Having issues.

First, I'm having no luck with the upper driveshaft seal. I've curled the metal but I can't get purchase, at least with the strike-cap screwdriver I've been using (the lower came out easy since I could use a socket to pop it out). Need to get a different tool that can catch more of the lip and knock it out. Both seals appeared to be failing... Found broken o ring in there too.

The other issue is that I found more pitting. Lower bearing and the gear nearby... See attached pics.

Maybe fetching a used outdrive isn't such a bad idea? Seems like more and more bad parts...

 

[ratdude747]

My luck may be turning... digging on Facebook Marketplace, I found somebody with a supposedly good MC-1 that happens to be off an 888 like mine (different year due to different stickers, but whatever) for cheap (reduced for not selling in nearly a year). Even has a stock prop (but not likely the 21P that I've been looking for). It's a good ways away in Tennessee, but as cheap as it is, I'll happily road trip for it. The lower half is missing a lot more paint but the u-joints aren't rusty.

 

[alldodge]

Speedy sleeve for seal surface
Need a bearing splitter to remove it from the gear

Good find on the MC-1 in TN, but note it may need new seals also

 

[ratdude747]

Speedy sleeve for seal surface
Need a bearing splitter to remove it from the gear

Good find on the MC-1 in TN, but note it may need new seals also

You think my gears are still worth using? I don't recall a lot of gear noise... but the pitting is concerning. If it was just one pit (or a few in one spot), I'd think nothing of it (the cam in my truck was like that when I rebuilt said engine... still going strong). But several teeth on both gears have a lot of shallow pitting.

 

[alldodge]

I don't see enough pitting on the gear posted to give me major concern with the motor you have. If there is worst spots then could be and I'm not there look and feel

 

[ratdude747]

I don't see enough pitting on the gear posted to give me major concern with the motor you have. If there is worst spots then could be and I'm not there look and feel

I showed the worst... but it's like that on several teeth on each gear. If I just need to replace bearings and knock that stubborn seal, then sure.

I found another 888 drive to the north of me (Gary, IN ) for even cheaper. Worn skeg though.

 

[ratdude747]

Got the seal out. Had to modify a harbor freight seal puller:



Also got a bearing splitter for the vertical shaft. How does one remove the bearing cups from the case and cover? Slide hammer? Special tool?

Edit- Bearing splitter too small for the large bearing (haven't tried the small). Bearings OK enough to reuse? Or do I need to use the cut and chisel method?

 

[ratdude747]

Got the bearings off. The trick for the big bearing (if using the Harbor Freight bearing splitter set) is to cut the cage and rollers off, then pull using the upper lip on the race. I also heated it with a poly torch but it wasn't all that warm by the time I actually pulled it.

The cups dont' look all that bad so I'll probably elect to reuse them. I do have a mini slide hammer with a 2-jaw puller so I may (carefully) try to pop them with such.

For those reading this in the future, it had all Timken bearings:

• 386A (X2)
• HM89449
• 09067

Looks like I have more shopping to do. Looking closer at the gears, the pitting isn't all that bad. Ideal, no, but it wasn't howling gears or the like...

 

[ratdude747]

Got the cups pulled too. Lower one was loose (got stuck, but slide hammer popped it out). Upper one put up more of a fight, but I used a light amount of heat to get it out.

That said... I was able to arrange a pickup tomorrow afternoon for the unit in Gary. Guy blew his engine last year and saved the drive from it. $50 and not leaking oil... I'll take it!

 

[ratdude747]

Got it. Not as good cosmetically (lower unit has corrosion) under the paint) but no leaking u joint. Plan will be to swap my lower over... Maybe reseal the upper since I have the parts?

Obviously I'll have to keep the case and gears together since I don't have a shim kit...

Edit: maybe I want to just salvage gears and yoke after all. Upper case is pretty chewed up. See second pic. Maybe between both I'll have enough shims to be able to make things right. I do have a test indicator that I used for setting backlash on my truck's rear end earlier this year...

 

[ratdude747]

Good news: the oil coming out is water free but looks like generic yellow/orange gear oil.

Bad news is the u joints are bad and the upper case damage is worse than I thought:



Both sides are cracked. There also is corrosion in the bell housing gasket area.

Making a case and joint swap with the old drive tempting but not sure if worth the trouble of having to check shimming. But replacement cases are a thing they sell, so it's justified on at least some cases?

 

[alldodge]

Bummer
That case is junk

 

[ratdude747]

I bought an anchor... The gears are worse!

Didn't spin smooth. Like at all.

Now what? Reuse my old gears and use new bearings? Or fetch the other drive I found this coming weekend?

 

[alldodge]

I'm not there but hide sight is always 20/20

If it was mine I would want to determine if a new SEI drive will fit but that's 2K

The other side remove the top cap and have a look before purchase

You can most likely get all new everything for your case

 

[ratdude747]

I'm not there but hide sight is always 20/20

If it was mine I would want to determine if a new SEI drive will fit but that's 2K

The other side remove the top cap and have a look before purchase

You can most likely get all new everything for your case

The other case the guy offered for free (was $100). It's just a long 4.5 hour drive away. Clearly an older one since it has the older "888" logo.

I can get gears, but that's a fair bit of $ (plus bearings and a speedy sleeve) and then I have to get all the shimming tools and the like. I'm tempted to use the gears I have and just watch for gear chunks in the oil. I don't like it though. $2000 for an sei (or $950 for just the upper) isn't in the budget.

Edit: attached is a better picture of the worst gear tooth in the old gears.

 

[alldodge]

Your old motor is not a HP big boy so using your old gears does not concern me, but this is your money and not mine

I would rebuild the one you have, but do check how much the special tools will cost. I spent over 700 just to do the lower on my B3 drive, and did that because there was no one around I could trust to do it correctly

 

[ratdude747]

Your old motor is not a HP big boy so using your old gears does not concern me, but this is your money and not mine

I would rebuild the one you have, but do check how much the special tools will cost. I spent over 700 just to do the lower on my B3 drive, and did that because there was no one around I could trust to do it correctly

I just don't want a failure on the water or to destroy the rest of the drive. Although given what I know about my lower (possibly worn-ish shift dogs), maybe I shouldn't care. Just throw some bearings at it and be done... and if it blows, SEI it in the offseason.

The cheapest I'm seeing gears is $315... that's on top of bearings and a speedy sleeve (not sure I dare pull the yoke from the other drive, I don't trust much in it at this point).

 

[ratdude747]

Cheapest I can get quality bearings (SKF) is $197 shipped... yikes. I'd spend about that (or less) that in gas fetching the other drive.

We'll see if I can get a day off... The drive does legit look better than this one. I've attached the pictures from the listing. No corrosion, just lost paint. And the U joints look very clean. 3rd time's the charm?

 

[ratdude747]

Got the drive home.



A mix of good and bad news.

First, I drained the oil... looking really nice:



At the end a bit of moisture, but hardly anything:



Tearing the drive down had some issues... first, bozo here hit the wrong spot with the mallet and broke the lower:



The shifting was very sticky, so this lower wasn't worth much at least. I also noticed that fully assembled I was able to turn the yoke without much impeller resistance (I was just checking for backlash, and it spun over!) Once I got it off, that mystery was solved as apparently the impeller blew up hard:



(look at the water guide tube... wasted!)

The upper spun nice and smooth. But, in the interest of verification, I popped off the top cover... and broke the bolts:



Whoops... I know a couple of machine shops so if this case gets used (see below) I could have those professionally drilled and helicoiled (not feeling lucky with vice grips and a torch!). I will also note that the trim cylinder pin is stuck in the case and the threads have a bad spot (nothing terrible, but the pins off the other two drives are in better shape.

On the plus side, the bearings and gears, while not mint, don't look terrible either. Some staining, but no pitting like I have in the other two drives.

Am I correct that to avoid needing to shim, it would be worth the $ to have this case repaired? Or am I better off to move the guts to the first case and somehow confirm/correct the shimming to fit the new case?

Edit- doing some reading... I do have a flux core welder at home. Not sure if it's good enough for welding nuts to studs here. I do have MIG access at work and via my Father-in-law. But I've also seen too many cases of people attempting a DIY extraction and ruining things.