Tohatsu M40C shift linkage

[jondavies]

I was out on the water yesterday when the pin in my M40C's shift linkage sheared off. I was able to repair the link with a piece of stainless cable so it wasn't a big deal and we continued our dive day without too much delay.

Now that I'm getting ready to make a permanent repair, I'm wondering if I should put another spring pin in there or whether I should switch to something more robust, such as a SS cotter pin or a SS rod etc.

Any advice from the experts would be appreciated.

 

[Sea Rider]

Re: Tohatsu M40C shift linkage

You can replace the original spring pin by part 951603-0899 (R.Pin) comes in 10 piece set. Simple and reliable. Can be removed instanly with plier if in need to drop the LU down at any moment.

Happy Boating

 

[jondavies]

Re: Tohatsu M40C shift linkage

That's along the lines of what I was thinking -- thanks!

 

[TOHATSU GURU]

Re: Tohatsu M40C shift linkage

You would be the only person I ever heard of who had one break, so just replace the pin and don't worry about it.

 

[pvanv]

Re: Tohatsu M40C shift linkage

You would be the only person I ever heard of who had one break, so just replace the pin and don't worry about it.

Ditto.

And though the R pin (intended to retain the RC shift and throttle clevis will fit, it is loose in the brass coupler (smaller than the 3mm roll pin), resulting in play in the shifter.

 

[jondavies]

Re: Tohatsu M40C shift linkage

Thanks for the replies.

I replaced the spring pin but when I took the boat out yesterday, the bottom section of the cam rod broke (sheared off just at the top where it connects to the brass coupler).

I've ordered a new cam rod from my dealer. I took off the lower unit but it's unclear from the FSM how to remove the cam rod. Per the instructions (page 35) I removed the cam rod bushing stopper bolt and yet the cam rod doesn't want to move. The diagram of the gear shift mechanism on page 42 seems to indicate that there's another spring pin at the base of the cam rod, in which case it appears I would have to strip the gear case to get to it.

Thanks again.

 

[Sea Rider]

Re: Tohatsu M40C shift linkage

Don't know if excessive banging the cam rod end while removing stuck pin inside coupler contributs to break rod's end faster, never seen a broken one, that's why use a clip which is faster to remove as the slight clip/coupler play has no effects whatsoever locking the gear forward or reverse properly...

Happy Boating

 

[pvanv]

Re: Tohatsu M40C shift linkage

If the shift coupler pin had been replaced with a non-stainless pin, it might have corroded, expanded, and broken the top of the rod. After you get the bushing out, you should be able to pull out the cam rod with the clutch cam still attached. The cam attaches to the rod with a stainless roll pin. Normally, you can give the rod a stiff tug, and the cam will pop out the bushing. While in there, replace both o-rings on the bushing, especially the pesky inner ring that is often overlooked.

 

[jondavies]

Re: Tohatsu M40C shift linkage

If the shift coupler pin had been replaced with a non-stainless pin, it might have corroded, expanded, and broken the top of the rod. After you get the bushing out, you should be able to pull out the cam rod with the clutch cam still attached. The cam attaches to the rod with a stainless roll pin. Normally, you can give the rod a stiff tug, and the cam will pop out the bushing. While in there, replace both o-rings on the bushing, especially the pesky inner ring that is often overlooked.

Thanks Paul. What do you recommend for getting out a stubborn rod once the bushing stopper bolt is removed? Clamp some vice grips on the rod and tap upwards? I don't want to create more damage.

 

[pvanv]

Re: Tohatsu M40C shift linkage

You should be able to operate the rod by hand. If so, give it a stiff tug. If the rod is seized, you may have other problems. Yes, since the rod is already fubar, you can clamp onto it to get more purchase. I am wondering whether there is a problem in the LU (rust from water contamination?) that caused the rod to be under unusual load, which led to the snapped pin, and the snapped rod tip.

 

[jondavies]

Re: Tohatsu M40C shift linkage

You should be able to operate the rod by hand. If so, give it a stiff tug. If the rod is seized, you may have other problems. Yes, since the rod is already fubar, you can clamp onto it to get more purchase. I am wondering whether there is a problem in the LU (rust from water contamination?) that caused the rod to be under unusual load, which led to the snapped pin, and the snapped rod tip.

Thanks again Paul. It came out using pliers with some gentle leverage. The top of the stopper was a little crusty but it was clean below the O-ring and the oil is clear.

Judging by the groove worn through the side of the brass coupler, the upper and lower cam rods were out of alignment for some reason and that's what caused the pin and the rod to shear.



Cheers!

 

[jondavies]

Re: Tohatsu M40C shift linkage

Thanks again Paul. It came out using pliers with some gentle leverage. The top of the stopper was a little crusty but it was clean below the O-ring and the oil is clear.

Judging by the groove worn through the side of the brass coupler, the upper and lower cam rods were out of alignment for some reason and that's what caused the pin and the rod to shear.

View attachment 174928

Cheers!

After taking the boat out for the first time since repairing the cam rod, I noticed that the spring pins in the linkage have already started to rust. I called the dealer where I bought the parts and they said that there's only one type of pin (951403-0312 SPRING PIN, 3 - 12) and they assume that they are supposed to be stainless but the ones I got obviously are not.

I found a source for the same sized pins made from 18-8 stainless steel. Any reason not to use these?

 

[Sea Rider]

Re: Tohatsu M40C shift linkage

Pins usually go out with some kind of corrosion after being on coupler for extended periods of time, original spring pins are probably not stainless steel made, you can place the ones you mention, no issue to worry about. Grease pin before sliding back into coupler.

Happy Boating

 

[pvanv]

Re: Tohatsu M40C shift linkage

The Factory pins are indeed stainless. The correct pin is 9514030312M SPRING PIN, and it is supposed to be stainless. All the ones I have here are. Maybe you got a substitute part somehow?