Help needed Tohatsu 40hp Trim/Tilt

[tigermullet]

Can anyone help. The trim tilt on the 40hp Tohatsu has stopped working.

Is the trim tilt unit easy to remove?

Looks like it needs a service and I don't want to haul the boat out. It will be easier to remove the unit on the beach and then take it for repair or whatever.

Got my comeuppance for not having regular services.;D

Thanks in advance.

[finga]

Can you hear the electrics trying to work? ie relays clicking or motors whirring

[tigermullet]

Thanks Finga. Yes electrics and motor seem to be going okay but there was a an escape of fluid from the unit. Do you reckon the seals might be gone??

[finga]

Sounds ominous to me.
Might be time for an upgrade or go to the gym for a while.

[tigermullet]

Thanks very much Finga. My brother is at the boat right now and has reported that he has been able to remove the bottom pin but is having trouble with the top pin. Persistence might win the day. We'll see.

He has also discovered that corrosion of the bottom of the unit is allowing hydraulic fluid to escape from one small pin hole.

If he can get it off, I will meet him and take the whole unit somewhere to be repaired or replaced. Replacement might be a tad expensive but cheaper than joining a gym;D

Strangely enough, the corrosion seems limited to the trim/tilt mechanism and the engine anode is in good condition.

I hope to find a method to fix that problem from happening again or, at least, reducing the problem.

I am also hoping that the bottom plate of the device can be repaired by some method. From what I have seen, the cost of replacement isn't going to be a cheap exercise.

[finga]

If it's a real small hole it might be able to be welded (pending where) or drilled and tapped so a fine threaded bolt can be put in to be the thumb in the pie so to speak.

[tigermullet]

Thanks again Finga. My brother is having trouble getting the top pin out but I am going down tomorrow with an assortment of tools + a heat source.

How do you reckon we would go (it is a very small hole) by drilling and tapping without removing the unit? That is, if we are unable to shift the top pin.

Would a waterproof rivet do the trick? I don't know how much clearance there is above the bottom plate housing.

[finga]

Who know old mate???
There could possibly be a fair bit of pressure in the oil there.
A fine thread would be better then rivet and welding (if possible) better still.

PS anything can be moved. Just use a bigger hammer ;)

[tigermullet]

That's the go - I have packed a large hammer and a length of steel which is just below the diameter of the top pin.

Tomorrow feels like a lucky day and I reckon your suggestions just might work.

One way or another the problem will be fixed but it's not such a mystery now that we have your advice.

The cost of a new unit just about floored me - $1000!

Many thanks.

[finga]

Mate, don't count your chickens until they're hatched.
If that area is so thin that corrosion made it leak it may be too thin to do anything with.
Closer inspection is the only way to tell what the go is.
Hopefully it will be fixable though :D

[tigermullet]

I will let you know what develops. Should be back home by Friday night.

[tigermullet]

Hi Finga - the unit is off. Heat and some persuasion did the trick. Tomorrow morning it will be delivered to a bloke, who comes highly recommended, for fixing.

It looks good. There is a solid and deep aluminium casting around the little plugs that have corroded to such an extent that hydraulic fluid was able to escape.

Why any manufacturer would put brass plugs (with allen key heads) into aluminium is beyond me but there might be a good reason.

[finga]

Great news then. :)
A drill and a tap and a clean and a oil refill and a test and jobs done.

[tigermullet]

Yep. All seems good. Why manufacturers or service people put bolts and pins back dry (without grease) is a mystery. It would be so much easier if that simple thing was done from the beginning.

I knew to undo the bottom leg bolts and grease them as soon as delivery was taken but hadn't give the trim/tilt top and bottom pins a single thought.

Thank you very much for your help. My brother and I are very grateful.

[cormorant]

If it doesn't have it put a earth cable from engine to tilt trim. Should slow it down acting as a annode. A lot of smaller motors don't bother with this as they don't expect their motors to be on moored boats. Check the electrial conductivity once you have it connected.

Use a isolating paste ( like duralac) when you put the bungs in and that will slow corrosion between dissimilar metals as well and the best is a acid wasn h and a complete fresh coating of paint while you have it off. good coating of paint is the best for stopping corrosion and you can buy teh ones they use as a primer on the underside of moored aluminium hull before they put antifoul on it will give real good protection. Good for engine brackets on moored boats as well.


Not too much heat with the removal as seals aren't real tolerant and shaft will conduct well and there may be nylon spacers in there bound up as well. Don't bur the end of the pin and make sure they haven't used circlips on both inside and outside of mounting bracket - they are hard to see.

Only use OMC or quality marine grease putting pins back as the other stufff gunks up and weldsstuff in as it goes solid.

Lots of other tricks - see how you go as some had a bad rep for corrosion issues

Good luck.

[cormorant]

If it doesn't have it put a earth cable from engine to tilt trim. Should slow it down acting as a annode. A lot of smaller motors don't bother with this as they don't expect their motors to be on moored boats. Check the electrial conductivity once you have it connected. Check there wasn't an extra annode that has completely cone from the motor mount bracket

Use a isolating paste ( like duralac) when you put the bungs in and that will slow corrosion between dissimilar metals as well and the best is a acid wasn , bead blast and a complete fresh coating of paint while you have it off. good coating of paint is the best for stopping corrosion and you can buy the ones they use as a primer on the underside of moored aluminium hull before they put antifoul on it will give real good protection. Good for engine brackets on moored boats as well.


Not too much heat with the removal as seals aren't real tolerant and shaft will conduct well and there may be nylon spacers in there bound up as well. Don't bur the end of the pin and make sure they haven't used circlips on both inside and outside of mounting bracket - they are hard to see.

Only use OMC or quality marine grease putting pins back as the other stufff gunks up and weldsstuff in as it goes solid.

Lots of other tricks - see how you go as some had a bad rep for corrosion issues

Bleed the thing several times as well as it takes a while to get air out of them and they will foam the fuid up

Good luck.

[tigermullet]

Thanks Cormorant. Strangely enough I was wondering about the corrosion on the lower part of the trim/tilt and, on the way home from delivering the unit for repair, was thinking about putting a bonding strap on the trim/tilt. Now, after reading your post, the bonding strap will definitely be attached

The anode on the lowest part of the bracket seems ok.

Fortunately we didn't come across circlips - hadn't even considered checking for those.

It was also a matter of luck that we used just enough heat and didn't melt the nylon spacers.

Bleeding is still a mystery but I hope to get a few tips from the mechanic on how to do it properly. I don't know if bleeding can be done as part of the repair and service seeing as the unit is off the engine.

Your points on painting, corrosion resistance etc., will also be done.

Great advice! Thanks again.

[tigermullet]

So much for counting my chickens...

Just got word back from the repairer. Drill and tap didn't work because the metal kept crumbling. A desperate attempt at welding was no go either. Too much corrosion as well as being infiltrated by the hydraulic fluid.

The cheap option disappeared but, at least, it's fixed by the purchase of a second hand hydraulic unit and using our old trim/tilt motor. I owe him $650. Ouch.:P