Lower unit- drive dogs help needed

[Steven Bates]

Hi again, I have issues with my gearbox (check my previous post- 125hp gearbox dramas...)
I tried to shift the linkage once i thought it was central literally 1/3 turn of the nuts at a time, no good. I had it to the point of reverse just clicking in perfectly, but still when it was at the point of going into forward chattering began, and shift rod just jumps crazy... i adjusted to the point of silly both ways... no good.

I've pulled off the lower unit now, as this only a 15 minute job (thanks Frank A...), and thought i would inspect gears for damage... all drained out, ready to go. took bolts of water pump and cover underneath it, tried to remove, no good!!! seems impossible to remove it, skinny looking piece of cast metal... Thats problem 1.
problem 2 is..:
i thought "ok i'll pull out gears via prop housing..." got anode? off, removed the four bolts, tried to remove plate with seal and bearing? in it,.. no good!!
im struggling... please can someone tell me how to remove these things, and inspect the drive dogs for damage? i looked at frank A's pics from my earlier post, and i just wanna get in there to see... cheers guys thanks

 

[Frank Acampora]

Re: Lower unit- drive dogs help needed

Oh! Yiou can't do that! LOL,.

The plate under the water pump has an O ring seal and it is difficult to remove. You can try using a chisel to get in the parting line and pry up. DO NOT pry on the forward or rearward "wings,



" they will break off.

The "spool" inside the lower unit that carries the prop shaft seal and bearing is again difficyult to remove because it has--depending upon year-- one or two O ring seals. You must remove the anode and four bolts (like you have done). Then, using some all-thread threaded rod you must fabricate a puller. Once the spool is out, there are two semi-circular clips that retain the reverse gear and prop shaft bearing carrier. Tap down lightly on the aluminum slug to loosen the rings then fish them out. NOW, the whole reverse gear/propshaft assembly will pull out of the gearcase.

You must remove the pinion to remove the forward gear. Last photo is of a two piece lower but essentially the principle is the same.

 

[Steven Bates]

Re: Lower unit- drive dogs help needed

Hi frank cheers mate! Got the plate off no breakages happy days... I found the problem!!! The little screw at the bottom of gear case that everyone pulls out has sheared off! I have been looking at the problem, and can't see a way to get the remainder of the screw out. I have one out of other motor so all good, when I compare it to the screw head that came out there must only be 2mm max of thread in the actual linkage... It's preventing me from getting it out any ideas on how to get it out? Cheers

 

[Frank Acampora]

Re: Lower unit- drive dogs help needed

The screw is actually 1/4 X 20 and there is more like 8 mm threaded.

I am puzzled though. When you say the screw has sheared off, where did it break? It slips into the hole and as you screw it in, it plugs into a hole in the casting on the opposite side. Very well supported and difficult to break. So: did the casting break also? Or did just the unthreaded portion break off and slip from the casting on the opposite side? Is the head of the screw buggered so you can not unscrew it?

If you bang the gearcase on its side and if the screw head is out, the unthreaded portion should slide out. You may need to find a very long needle nose pliers and reach in to work it out

 

[Steven Bates]

Re: Lower unit- drive dogs help needed

lol is hard to explain= of the 8mm of thread, 6/7mm stayed on the screw head, the other 1mm is still in the arm bit. it snapped just on the threaded side of the smooth pin... I can see where it slips into other side of casing, and it seems ok. there just doesn't seem to be a way to get the rest of pin out, as it still has a tiny bit of thread in the arm... i have a new pin out of my other motor ready to go in... was thinking if i can drill out the rest of thread it might slip out then, but im at the risk of damaging the thread the pin screws into... conundrum....
side note- how does the arm attach to bottom selector rod? via pin or? only asking as in the recent post 'slick trick for reinstalling arm' he suggests you can drop it down and line it up... I was thinking if thats so, i could try cut/snap rest of pin down in housing, pull out whole arm and top gear rod, remove threaded bit and reinstall... your thoughts? thanks again mate... I'm gunna owe ya a carton by the time my boat just gives turn key happiness... hahahaha!!! cheers

 

[Frank Acampora]

Re: Lower unit- drive dogs help needed

Up here we have Sears. They sell a special set of extractors for stripped phillips head screws. Explanation:

Since the screw is broken at the threaded portion and since it is most likely not under a lot of pressure, AND it probably does not have corrosion because it is usually bathed in lower unit oil (the seal is on the outside, under the screw head):

Try to find these extractors down there. They look a lot like a center drill except they are run in the hand drill in reverse. That may do the trick. Use the smallest size. It should fit inside the threads. It should start to drill then grab and back out the screw.

Don't try to drill the screw out except as a last resort. Unless you have special tools the drill bit will not center and you will ****-up the threads.

As I said before, you can also try using a very long needle nose pliers but that will be an excercise in patience.