Yb 6075 nut wrench

[JRM80000]

I have an 89 30 hp yamaha that is loosing grease in the lower unit. I see no signs of leakage, but it nevertheless is leaking, I think from the bearing carrier o rings. I have already resealed the prop shaft, drive shaft and the gear shift rod and see no leakage there. It will only hold about 5 lbs pressure before I hear a whooshing sound from somewhere inside. That means it has to be the o rings. The problem is the retainer nut for the bearing carrier. That nut is not going to come out voluntarily and as much as I would like to avoid buying the ring nut wrench, it looks like I won't have much choice.

Which brings me to my problem. I can't find one. Newer engines, I can find, but not this one. Can anyone tell me where I can locate one to borrow, rent or buy? My engine is a 1989 30 hp elf.

Thank you,

jrm80000

[TownsendsFJR1300]

That nut usually gets destroyed in the removal, if there's ANY chance of even removing it.

Simply use a dremel or cut off wheel and cut it off. Then replace with a new nut when re-assembling. Much cheaper than the tool that likely won't remove that nut anyway..

BTW, if you pressurize (no oil) the LU, spray some soapy water, Windex in the area you suspect. You should see some bubbling from the air (lots of bubbles with what you describe). Just like finding a slow leak in a tire...

Please post back how it goes...

[99yam40]

No help in finding where to buy that tool, but have you thought about taking it to a Yamaha dealer to see if they had the tool and remove/install it for you?

Even if you drill and cut the nut, you still will need one to tighten it back up to proper torque.

other choice is to make one or have someone else make one for you.

I would identify where it is leaking before going through the removal of carrier.
Could be the seals are holding until pressure over comes them for some reason. are you sure you installed them in the correct direction?

[JRM80000]

Well, there's good news and bad news. I found the leak and it's not where I thought it was. Although I had previously replaced the drive shaft seal, I found bubbles coming from that area, so I took the water pump base out and found a crack in the housing that surrounds the pump base. It's a hairline crack, and from the silicone debris I found inside, it is obvious that somebody had been there before. The question now is what to do about it. The easy and expensive solution is to replace the lower unit housing. Instead, I think i am going to try filling it with BELZONA. If it works, I have saved a bunch of money and if it doesn't, I'm no worse off than I am already. If it passes the pressure test, I should be good to go and as long as I keep an eye on the oil level in the lower unit, I should be ok. Any thoughts?

[TownsendsFJR1300]

Can you shoot and post a couple pic's using Photobucket (pic's are much larger)?

That's a really an odd place to crack....

[JRM80000]

Photos lower unit

[ATTACH]2798[/ATTACH]

[ATTACH]2799[/ATTACH]

[ATTACH]2800[/ATTACH]

[ATTACH]2801[/ATTACH]

[ATTACH]2802[/ATTACH]

[JRM80000]

I think I got the photos to go through. There is some corrosion at the top of the housing that I'm not worried about as it is above the o ring, but the crack begins at that point and does extend below it. After thinking about this a little more, I may just try sealing it with more silicone and see what happens. It may well have been sealed before I removed it a few years ago to replace the drive shaft seals, and the seal broken at that time. Who knows? You're right, this is a peculiar place for a crack as there is not much stress on it and other than a manufacture defect, I cannot account for it.

[TownsendsFJR1300]

If you can see the end of the crack, on the outside of the machined part, a heli-arc welder might be able to get in there...

I would NOT use silicone.

That area needs to be cleaned SPOTLESS and the outside of the damaged part roughed up a little(for adhesion). Yamabond 4 is used for crankcases (no gaskets) and seals EXTREMELY well (IME, way better than silicone).

I believe there is a Permatex equivalent to the Yamabond but I don't know what it is...

JB weld, an Epoxy, also works very well and once set up, is very durable.

I'd probably clean it super clean, JB weld, then a coat of Yamabond..

[JRM80000]

I'll do it. As it happens, i have some yamabond 4 and of course everybody has jb weld. That should give me the time to look around for a used lower unit housing to replace this one if need be. Fortunately, new ones are nla so i don't have to agonize over the 750.00 they want for a new one even if it were available. Thanks for the help.

[TownsendsFJR1300]

Here's a Suzuki 140 that had a cracked LU (about the same crack on each side). The aluminum is very thin to start with. Buying a repaired or repairing yourself is the only way you can go.

We dis-assembled, had it welded, did the clean up and re-assembly.

Something we thought about later re finding a good welder, go to a PROP SHOP!! They do thin edges on aluminum props rebuilding them....

Before-RIGHT SIDE (prepped):




After:

[pstephens46]

Townsend - is that lower unit still in service?

[TownsendsFJR1300]

Townsend - is that lower unit still in service?

Sure is!

Left side before the repair:

Suzuki uses two smaller bolts at the end of the carrier to hold it in (unlike the one large nut yamaha does).
Corrosion on the outer part of the carrier pushes out and splits the housing. The housing is pretty thin to start with..

It took some serious torque with my HD puller, BFH to initially pop that carrier off with the help of a heat gun.

[pstephens46]

Wonder what the actual operating pressure might be for a typical lower unit? Wonder if Fairdeal might tap a hole with hose/guage and let us know?

[pstephens46]

Aluminum prop on that Suzuki? Salt water?

[TownsendsFJR1300]

Aluminum prop on that Suzuki? Salt water?

Yep, aluminum prop.

Brackish / salt water depending on how much fresh water they dump down river from Lake Okeechobee, Fl.

There really shouldn't be any pressure to speak of inside the case when operating. Its not like a piston going up and down, just gears turning..

PSI testing, depending on the unit(with no oil), is around 12 PSI to keep water out...