C40TLRX gear box drive shaft seals replacement

[99yam40]

good new is I got the prop shaft seals out without destroying anything but a drill bit and the seals.
bad news is I did not put the shift shaft back in to hold the shift cam in place while I was working on removing the seals, and I cannot find the shift cam to slide the shift shaft into now, so looks like I will have to pull the carrier anyway.

this sucks

[pstephens46]

The big weird nut is called a gland nut. And yes it is sometimes better to cut it out if it is corroded. They won't come out even if you have the proper gland nut tool sometimes and you just end up tearing it all to pieces.

My motors have two bolts that hold the carrier in place.

So the propshaft is retained by the carrier I assume. That gland nut is a pathetic design. Basically welds itself to the housing over time in salt. At least that is how mine appears.

[TownsendsFJR1300]

I believe his carrier is held on with the two bolts.

In my post, #33, I posted a parts link for HIS LU and yes it is bolted on with TWO bolts.

[walleye1]

I believe his carrier is held on with the two bolts.

[panasonic]

In your F150 for instance, the carrier : https://www.boats.net/catalog/yamaha...g-drive-1-f150 holds everything together. The carrier is held into the lower unit case by the big weird nut, part #72. Once nut #72 is out, (RB often speaks of just cutting it out due to corrosion), the guts would come out(not sure if the shifter shaft has to come out first)..

That Suzuki 140 OB, with the badly cracked LU case, which we had welded(couple years ago I posted about), the carrier was held in with two bolts facing the prop. Once those two bolts came out the carrier came out, the prop stayed in the LU, unless you simply pulled it out (which we did for clean up before re-assembly..


Actually, 99yams is the style as the above Suzuki. Two bolts hold the carrier to the LU: https://www.boats.net/catalog/yamaha...casing-drive-1 The bolts are part numbers 44 in this link...

The big weird nut is called a gland nut. And yes it is sometimes better to cut it out if it is corroded. They won't come out even if you have the proper gland nut tool sometimes and you just end up tearing it all to pieces.

My motors have two bolts that hold the carrier in place.

[TownsendsFJR1300]

Somebody explain please. Does pulling the shift shaft allow for “pulling the carrier and propshaft together”? My understanding is the carrier is held in place by orings. What holds the propshaft in place? If I run my motor in reverse at 4500 rpm, what keeps the shaft and prop from popping off and ending up at the bottom of the ocean?

In your F150 for instance, the carrier : https://www.boats.net/catalog/yamaha...g-drive-1-f150 holds everything together. The carrier is held into the lower unit case by the big weird nut, part #72. Once nut #72 is out, (RB often speaks of just cutting it out due to corrosion), the guts would come out(not sure if the shifter shaft has to come out first)..

That Suzuki 140 OB, with the badly cracked LU case, which we had welded(couple years ago I posted about), the carrier was held in with two bolts facing the prop. Once those two bolts came out the carrier came out, the prop stayed in the LU, unless you simply pulled it out (which we did for clean up before re-assembly..


Actually, 99yams is the style as the above Suzuki. Two bolts hold the carrier to the LU: https://www.boats.net/catalog/yamaha...casing-drive-1 The bolts are part numbers 44 in this link...

[99yam40]

SS is stuck down in a part that needs to come out. on some units.

we have no idea what motor you have so hard to say about what holds things in

[pstephens46]

if this motor has ever seen salt or brackish water do yourself a favor.
fuggit about pulling the carrier.
wont come out.
they made the c 40 shift in two desighns.
if your pushs and pull don't worry about it.
if it rotates left and right then pull the shift shaft.
have a machine shop make you an adapter with your slide hammer thread on one end and the propshaft thread on the other.
pull the shaft and carrier together.

Somebody explain please. Does pulling the shift shaft allow for “pulling the carrier and propshaft together”? My understanding is the carrier is held in place by orings. What holds the propshaft in place? If I run my motor in reverse at 4500 rpm, what keeps the shaft and prop from popping off and ending up at the bottom of the ocean?

[99yam40]

I went out and looked again and there does look like a lip along the inside of the outside diameter of that carrier that that puller might catch good enough on,
the puller I rigged up put a lot of pressure on the carrier hooked to the web from the inside shaft area and the outside that is in contact with the lower housing, but I did not put heat on the housing.
but I will try to replace prop shaft seals without pulling the carrier to see how that goes 1st.

[walleye1]

I have pulled a lot of them using that type of puller.

[99yam40]

the main problem is there is no place for arms to hook onto facing in or out.
Have to grab the web.

I have pulled the bigger carriers that have the claw nut.
But I rigged up to pull them with the prop shaft threads and braced against the housing itself.

this C40 is way different.

Big a$$ slide hammer maybe, and someway to hold the lower unit from moving with out damaging it

[zenoahphobic]

Most likely it won't fit. The prongs will be too big, and the centre bolt certainly won't fit "over and on" a driveshaft, prop shaft or gear rod.

[walleye1]

Turn the arms around. An auto parts store will loan out one.

[TownsendsFJR1300]

I do not see how that puller would work on this C40.
I set up on like the manual shows(harmonic balancer type puller)

I will take my chances replacing the shaft seals only for now and see what happens

Agreed, might be opening a can of worms should that carrier break being 20 years old. I wouldn't touch it (remove) un-less absolutely necessary..

Just my 2cts..

[99yam40]

I do not see how that puller would work on this C40.
I set up on like the manual shows(harmonic balancer type puller)

I will take my chances replacing the shaft seals only for now and see what happens