Stern drive Case Material

[tfitch03]

Re: Stern drive Case Material

I don't feel like there is supposed to be water in my shift linkage cavity, is that accurate? If it is normal for water to be in there I wont mess with anything but if it is supposed to be dry I will have to do something to seal that crack AND find out where the leak is that initially let the water get in there and freeze in the first place.

What I am hearing you all say is somehow water got in there, froze, and cracked the case and; through the normal winterizing process of draining the water from my cooling system there would have been no way to protect against the water intrusion in my shift linkage cavity. The only way I could have discovered that would have been to pull the drive. Bruce, I think I will heed your word and pull the drive EVERY winter now regardless.

 

[bruceb58]

Re: Stern drive Case Material

That cavity always gets water in it. That is why OMC came out with a bushing for the bellcrank in later Cobras that has a grease fitting on it that forces grease into that cavity. The problem people have that boat in salt water is that salt water gets in there and then evaporates leaving a crusty mess that makes your shifting harder.

 

[Reinell-BRXL-191]

Re: Stern drive Case Material

I would just sand the surface to remove paint, grind a V in the crack, and JB Weld it... make sure when you put it back together to fill that void with grease...

 

[tfitch03]

Re: Stern drive Case Material

Thanks everyone for the advice. I am learning a lot on here. I will post an update once I knock this item off the punch list.

 

[HT32BSX115]

Re: Stern drive Case Material

That is a MUCH better picture and I'll agree with the others.

It appears to be an area that had pooled water that froze.

You could weld it, but it probably wouldn't make much difference.

Since it's essentially a NON-structural area, just run it. It'll probably outlast the rest of the drive!

 

[jerryjerry05]

Re: Stern drive Case Material

The older Cobra drives weren't engineered all that well.
They were prone to water intrusion and corrosion buildup on moving parts.
Just loosining the bolts and letting excess water drain out would stop that.
It's in area that's not critical.Since it's a crack. It's never gonna get cleaned out the right way so JB or silly putty won't last.
Aluminum welds good..Since it's in a non critical area it can be welded without taking the drive apart.
Or just silicone it and spray paint it. You cant see it at 35mph anyway!!!
Dallas don't freeze much but it only take a couple of hours to break aluminum.
The shift mechnism on the bell housing, it gets water in and around the bell crank.
It will eventually sieze the bellcrank and posibly break a cable etc.
If you dis-assemble it remember the position of the crank and how many turns on the screw??

 

[bruceb58]

Re: Stern drive Case Material

It's never gonna get cleaned out the right way so JB or silly putty won't last.
Or just silicone it and spray paint it. You cant see it at 35mph anyway!!!

So you think silicone is going to last longer than JB weld?

Also, whenever disassembling the cable from the bellcrank, it is imperative that the proper tools be used to adjust the cable again.

 

[tfitch03]

Re: Stern drive Case Material

I am horrified to touch anything to do with the shifting. I have read and heard everywhere that an improperly adjusted shift linkage on a Cobra will ruin the drive in no longer than a 3 potato. After I complete my work I will be hauling it in to a mechanic for proper adjustment.

 

[bruceb58]

Re: Stern drive Case Material

Its actually not that bad if you have the two tools to make the adjustment. Its when people do it without the tools where they have problems. You absolutely need both of the tools.

 

[tfitch03]

Re: Stern drive Case Material

Its actually not that bad if you have the two tools to make the adjustment. Its when people do it without the tools where they have problems. You absolutely need both of the tools.

tools inbound.

 

[HT32BSX115]

Re: Stern drive Case Material

tools inbound.

It's not hard to adjust one, and once properly adjusted, they shift as good as any other drive.

 

[jerryjerry05]

Re: Stern drive Case Material

If you'd have read my post I told him to weld it first.
No silly the sillycone is just to cover it and stop water from leaking in again.
JB Weld is junk and if you use it your just doing half a job.
You'd be supprised how many try to clean out the bellcrank with out the right tools.
I was just telling him to be carefull when he did do it or he'd be paying.
99.99% of owners don't know there are tools for that job.
I have em.
One thing I've noticed here in Fl. The sterndrives are in a minority here.
Way more outboards.

 

[Lou C]

Re: Stern drive Case Material

That is an area where there is not supposed to be water, but it can get in. I'd get it welded, to keep water out. Then in the future, when the gasket is replaced when R+Ring the drive, coat it well on both sides with OMC gasket sealer. That's what I do and I don't get water in there, just a little sediment build up but I also pack the area around the bellcrank with OMC triple guard grease. Doing the coating the gasket thing and packing the bellcrank with grease, has resulted in my being able to use the same transom shift cable (I've had the same cable on there the whole 10 years I have the boat) and it was last adjusted in 2004, with no shifting troubles at all. And my boat sits in salt water 6 months out of the year. Keeping the drive down also helps make the cable last longer. Get the tools for sure, I picked up the OMC oe ones since I figure sooner or later I will have to do the cable. Still shifts with 2 fingers though and never jumps out of gear.

 

[bruceb58]

Re: Stern drive Case Material

The water can get in from the backside where the cable goes in. That is why OMC came out with the bushing with the zerk fitting. I replaced mine many years ago when I still had my Cobra.

 

[Jammer864]

Re: Stern drive Case Material

Wet sediment builds up in that area, then freezes and cracks it. I had one that did that and we used a MIG welder with aluminum wire to fix the crack. Being aluminum, the heat is dissipated quickly and a couple inches away from the weld, the metal was still cold. We sanded down the welding bead, repainted, and cant ever tell it was there.

 

[tfitch03]

Re: Stern drive Case Material

The water can get in from the backside where the cable goes in. That is why OMC came out with the bushing with the zerk fitting. I replaced mine many years ago when I still had my Cobra.

He Bruce, is there a factory mod or part number for the bushing with zerk or is it just a back yard mod?

 

[tfitch03]

Re: Stern drive Case Material

Wet sediment builds up in that area, then freezes and cracks it. I had one that did that and we used a MIG welder with aluminum wire to fix the crack. Being aluminum, the heat is dissipated quickly and a couple inches away from the weld, the metal was still cold. We sanded down the welding bead, repainted, and cant ever tell it was there.

I am most likely going the route you did. I have never tried to weld aluminum so I will prob have to take it somewhere. What do you think about brazing it together? Easier, harder, as good?

 

[RogersJetboat454]

Re: Stern drive Case Material

I am most likely going the route you did. I have never tried to weld aluminum so I will prob have to take it somewhere. What do you think about brazing it together? Easier, harder, as good?

Your best bet for a proper repair is to bring it to an aluminum welder, and have them determine the best course of action. Aluminum is not a forgiving metal to try your hand at welding or brazing. It doesn't glow like steel or iron does when you're heating it, so gauging the proper temp is not at all easy. There's a fine line between working temp, and melting temp.

 

[bruceb58]

Re: Stern drive Case Material

He Bruce, is there a factory mod or part number for the bushing with zerk or is it just a back yard mod?

Its on the later drives. You can see it here #79:

OMC Stern Drive Transom Mount Parts for 1993 5.0 L 50FAPLJVB Stern Drive

What I don't recall is if you need the newer bellcrank shaft.

 

[tfitch03]

Re: Stern drive Case Material

Cool Thanks. I will take a closer look at my setup.