I replaced My old two stroke with an old two stroke.

[paintman]

I'd also go with beamishken's suggestion.
If you get the steering tube nice & warm with the blowtorch - not to the extent of melting stuff - & keep turning the steering you may well find that it will free up & be a lot easier.
Been there done that!

Keep pumping the new grease in to displace the old. Forget the WD40, I much prefer PlusGas for freeing off rusty things - the old acetone/diesel mix works too.

[fastasfox]

Originally Posted by beamishken

I think it would be a shame to throw the towel in at the first hurdle but on the other hand I can see why you wouldnt want to get into a big repair straight away.
The way I'd go would be do the bare minimum to get it useable, if you heat the siezed swivel bushes they start to soften (melt) & free off once free enough to be useable I'd get it on the boat & see how it goes if it runs great then you know its worth the effort to strip & fix properly in the winter. If it runs like a 3 legged camel then punt it as spares. Even selling as spares if it starts & runs even rough you'll get more money so worth the effort to get running. Mercury engines in general suffer less with snapped bolts that the Japanese engines. Not sure if they use better stainless or better ally but they seem to come apart better.
Also remember with it being an optimax when its running right it will be better on fuel than an old school 2 stroke so in some ways better than a conventional 2 stroke.
I definitely think you need to evaluate how it runs further before digging into a big repair

Yep makes complete sense Ken....but you know when you see something that's not right and you start digging around....you just want to make it right!
The reason I'm encouraged to do a proper job is the fact that the powerhead is as you know, in pretty good shape ..when's the last time you did a compression test on a 20 year old engine where not only the psi reading are good but they are even accros all cylinders?
I will take your advice and spend next weekend trying to improve things further with the steering.
Cheers Ken.

[fastasfox]

Originally Posted by tinker

Problem is that your not planning to keep it so how much time and effort do you want to invest. If the compression figures are good and there ain't to many rusted bolts then it maybe worth a few hours and some cash to get it running OK, you kept your old outboard for years so why not keep this one for a few?

My instinct would be to follow beamishken's advice, get some heat on the emulsified grease and try and pump fresh grease through it, clean the rust up, treat and paint and then run it with a pony motor up and down a river or around slack tide. Once you have built some confidence up in it you may see things differently and keep it for 10 years....

I'm hoping to bring the optimax back up to a good standard so when I sell it I will have a chunk of cash towards the end goal outboard.

I'm not so sure the problem is hardened grease...I think the swivel mount tube is rotten as a pear.
The best course of action will to source a good used swivel mount (new are very expensive) and put new bushes and seals in.
For now I will keep trying to free it up and like Ken said,give it a good shakedown to see how it performs.
I think the only reason the powerhead is in much better nick than the lower unit and leg is that the side cowling goes right down the leg to the lower unit and the engine hood seals the two together, thus keeping the saltwater and rain out......All the bolts still have paint on with very little rust to speak of.....fingers crossed it pan's out mate.

[fastasfox]

Anyone know what the blue sheathed wire is? it was plugged into the engine and ran to the console, alongside the 8 pin harness.
The main 8 pin harness is exactly the same as the one I already have on my boat and that powered the ignition kill switch and Rev counter... Is the blue harness for digital guages ?

[beamishken]

I did a steering tube a while ago absolutely siezed solid only way I freed it was get it so hot the bushes melted, the problem was a fairly minimal amount of corrosion inside & behind the bushes which had swelled & locked it solid. After I'd got it free it turned fine & could have been used as it was but I stripped it cleaned out the corrosion fitted new bushes & it was fine. Dont be scared to get it warm if you need to but if you have it moving at all your half way there plenty release fluid & working it will likely get it free enough to get out for a sea trail. Id hazard a guess that cable is for auxiliary guages.
I'd be surprised if the engine didnt run okay, I was having a good chat with the guy while you were strapping it down & he seemed 100% genuine that it ran fine. Only concern would be damage from standing since the fire with contaminated fuel in the vst but when I drained it into my hand it was clean as a whistle & didn't smell bad

[fastasfox]

Originally Posted by beamishken

I did a steering tube a while ago absolutely siezed solid only way I freed it was get it so hot the bushes melted, the problem was a fairly minimal amount of corrosion inside & behind the bushes which had swelled & locked it solid. After I'd got it free it turned fine & could have been used as it was but I stripped it cleaned out the corrosion fitted new bushes & it was fine. Dont be scared to get it warm if you need to but if you have it moving at all your half way there plenty release fluid & working it will likely get it free enough to get out for a sea trail. Id hazard a guess that cable is for auxiliary guages.
I'd be surprised if the engine didnt run okay, I was having a good chat with the guy while you were strapping it down & he seemed 100% genuine that it ran fine. Only concern would be damage from standing since the fire with contaminated fuel in the vst but when I drained it into my hand it was clean as a whistle & didn't smell bad

Yes I agree, the fella seemed genuine enough.
I think the problems this outboard has, were due to the previous owners lack of basic maintenance, with regards to greasing the pivot points......such a simple job. I think the boat was stored outside since the fire and this has seized the steering.
Next step after freeing up the steering is to stick it on my boat...plug it in and fire her up....fingers crossed.

[whiskylee]

Originally Posted by fastasfox

Anyone know what the blue sheathed wire is? it was plugged into the engine and ran to the console, alongside the 8 pin harness.
The main 8 pin harness is exactly the same as the one I already have on my boat and that powered the ignition kill switch and Rev counter... Is the blue harness for digital guages ?

Can bus data lead for digital gauges

Smartcraft gauges will give lots of useful information from the ECU: temp, water pressure psi, engine faults etc

Lots of free downloads for your engine & smartcraft gauges

Google smartcraft operation manual & mercury optimax operation manual 75hp ?

My advice would be to hook the ECU up to a DDT terminal before running, this will give you lots of info reference to air injectors, fuel injectors as they can be test run

The optimax is a complex engine with expensive bolt on parts, compressor, air injectors etc ( we ran an early 150hp optimax years ago and it wasnt a great experience financially)

All the best 🤞

[whiskylee]

https://youtu.be/88u0TdOo6vI?si=rpvOQCsXVbGm8TOQ

Google and YouTube is your friend

[fastasfox]

Originally Posted by whiskylee

https://youtu.be/88u0TdOo6vI?si=rpvOQCsXVbGm8TOQ

Google and YouTube is your friend

Born again boating on youtube,has been a great source of info recently.

[fastasfox]

Originally Posted by whiskylee

Can bus data lead for digital gauges

Smartcraft gauges will give lots of useful information from the ECU: temp, water pressure psi, engine faults etc

Lots of free downloads for your engine & smartcraft gauges

Google smartcraft operation manual & mercury optimax operation manual 75hp ?

My advice would be to hook the ECU up to a DDT terminal before running, this will give you lots of info reference to air injectors, fuel injectors as they can be test run

The optimax is a complex engine with expensive bolt on parts, compressor, air injectors etc ( we ran an early 150hp optimax years ago and it wasnt a great experience financially)

All the best 🤞

I think almost every conversation about boats end's with " That wasn't a great experience financially " lol

The 8 pin harness on my old Mariner 75hp is exactly the same as the one on the optimax. At the moment I only have one guage....a rev counter. Do I take it that as it's analogue it won't work on my optimax?
Does the smartcraft gauge with the small lcd screen show the data from the optimax? Cheers.

[whiskylee]

Originally Posted by fastasfox

I think almost every conversation about boats end's with " That wasn't a great experience financially " lol

The 8 pin harness on my old Mariner 75hp is exactly the same as the one on the optimax. At the moment I only have one guage....a rev counter. Do I take it that as it's analogue it won't work on my optimax?
Does the smartcraft gauge with the small lcd screen show the data from the optimax? Cheers.

Ok I was trying to be polite about my optimax experience, we wasted £1000's making it run correctly, the steering arm was very corroded when we bought it, so I had the power head lifted off and a new steering arm fitted, then on our first outing the engine died! All 6 cylinders were low on compression! We had some how cooked the engine, I had it rebuilt ££££, then every time we took the boat out we had an air injector fault that puts the engine into limp mode, I bought a DDT as I was tired of taking the boat/engine into a mercury dealer for diagnosis, anyway after 6 air injectors @£238 each it ran ok for a few outings then the lower unit (gearbox broke) I found a second hand lower unit put it on the optimax 150 then sold it ! I think we spent £6k on repairs and got £2.5k for the engine. I learnt a lot about optimax engines back then 😁

[fastasfox]

Originally Posted by whiskylee

Ok I was trying to be polite about my optimax experience, we wasted £1000's making it run correctly, the steering arm was very corroded when we bought it, so I had the power head lifted off and a new steering arm fitted, then on our first outing the engine died! All 6 cylinders were low on compression! We had some how cooked the engine, I had it rebuilt ££££, then every time we took the boat out we had an air injector fault that puts the engine into limp mode, I bought a DDT as I was tired of taking the boat/engine into a mercury dealer for diagnosis, anyway after 6 air injectors @£238 each it ran ok for a few outings then the lower unit (gearbox broke) I found a second hand lower unit put it on the optimax 150 then sold it ! I think we spent £6k on repairs and got £2.5k for the engine. I learnt a lot about optimax engines back then 😁

It's fair to say then that you're no fan of the optimax lol
Being fair to your optimax, most of the problems you listed could happen to most outboards, and like the problem with mine, it all comes down to how it's been looked after.
I will try and start mine, and if it's okay, I will stick on my boat and test it on the river trent....not ideal, I know... but we do have an unrestricted section for water sports.
If it is a dud, then I will just re-list it as spares or repairs.

[fastasfox]

Originally Posted by beamishken

I dont think you need to justify your purchase to this clown hes not worth the forum space.
Re the reliability or otherwise of direct injection 2 strokes my take on them is they are great when running right go realy well good on fuel & sound pretty good too but as soon as they start giving fuel or running problems its time to bail out. You realy cant loose with your engine apart from a little wasted time, time you sell the trailer a frame & maybe return a little on the hull youll be into the engine for the value of the power trim & a few other bits you will sell if you break it for spares. If you get it running even poorly & sell with a steering problem you'll make profit. If you sea trail it & it runs well then you strip it & repair the steering properly run it a season or two then sell it as a good "can be tried on the water" engine you'll make a 4 figure profit ,
In my experience direct injection 2 strokes are the worst of all worlds too complex to be easy to maintain & when they do go wrong in the fuel/running department the problems start to snowball. That goes for etec yam hpdi & optimax. If this one runs well on a trail id happily strip it & sort the steering out properly, your obviously a handy guy & wont be paying £90/hour+ labour & theres not a lot of expensive parts required to sort the steering.
Whichever way it goes you wont loose out financially. In all honesty on the day if youd said I don't want it cos the steering was stuck I'd have bought it myself.

Originally Posted by beamishken

I dont think you need to justify your purchase to this clown hes not worth the forum space.
Re the reliability or otherwise of direct injection 2 strokes my take on them is they are great when running right go realy well good on fuel & sound pretty good too but as soon as they start giving fuel or running problems its time to bail out. You realy cant loose with your engine apart from a little wasted time, time you sell the trailer a frame & maybe return a little on the hull youll be into the engine for the value of the power trim & a few other bits you will sell if you break it for spares. If you get it running even poorly & sell with a steering problem you'll make profit. If you sea trail it & it runs well then you strip it & repair the steering properly run it a season or two then sell it as a good "can be tried on the water" engine you'll make a 4 figure profit ,
In my experience direct injection 2 strokes are the worst of all worlds too complex to be easy to maintain & when they do go wrong in the fuel/running department the problems start to snowball. That goes for etec yam hpdi & optimax. If this one runs well on a trail id happily strip it & sort the steering out properly, your obviously a handy guy & wont be paying £90/hour+ labour & theres not a lot of expensive parts required to sort the steering.
Whichever way it goes you wont loose out financially. In all honesty on the day if youd said I don't want it cos the steering was stuck I'd have bought it myself.

We both have the benefit that we have been in front of the outboard and we all know how expensive outboards are at the moment.
I think I stated that ordinarily I wouldn't have looked at the optimax because of the added complication but as they say beggars can't be choosers and they are not a bad outboard....mercury built them long enough ( I think late 90's to around 2017 ish).
When we did the compression test and looked at the bores, I think we both thought the same thing.....this outboard has potential.
If the outboard free's off this weekend then I will mount it on my boat and try and start it....If not then I will start stripping it down to do the repair.

[Mod Edit]

Cheers Foxy.

[fastasfox]

I wiggled it all afternoon.....Wd40 two stroke oil grease and heat....lot's of heat.....but no Joy it was still stiff.
The problem with the steering is the top Bush is heavily corroded and as such is swollen making the steering tight. The bottom Bush is also knackered so has some play in it.....so I thought if I can get a crowbar between the steering arm and the saddle bracket I could get some oil down the top of the swivel bracket......Bingo she is free.
Next step is to mount it on my boat and see how it runs.

[beamishken]

Originally Posted by fastasfox

I wiggled it all afternoon.....Wd40 two stroke oil grease and heat....lot's of heat.....but no Joy it was still stiff.
The problem with the steering is the top Bush is heavily corroded and as such is swollen making the steering tight. The bottom Bush is also knackered so has some play in it.....so I thought if I can get a crowbar between the steering arm and the saddle bracket I could get some oil down the top of the swivel bracket......Bingo she is free.
Next step is to mount it on my boat and see how it runs.

Round one to you👍
Hopefully the test run goes well 🤞

[fastasfox]

Fingers crossed.

[tinker]

Nice work, one obstacle overcome onto the next one, only one winner 🏆

[Fenlander]

>>>Bingo she is free.

Excellent, very satisfying. In a pre-retirement life we had a fair bit of old farm equipment and such endeavours with seized rusty pivots involving grease, oil, heat, levers, hammers etc were common.

Its surprising how often a few goes attacking with different ideas/methods will sort the most impossible problem.

[beamishken]

Heres something to spur you on, look at the price of this not a great deal different from your engine.
https://www.ebay.co.uk/itm/326125387...mis&media=COPY

[fastasfox]

Originally Posted by Fenlander

>>>Bingo she is free.

Excellent, very satisfying. In a pre-retirement life we had a fair bit of old farm equipment and such endeavours with seized rusty pivots involving grease, oil, heat, levers, hammers etc were common.

Its surprising how often a few goes attacking with different ideas/methods will sort the most impossible problem.

I have a saying.......you can be Rich or Resourceful....and I ain't Rich.

Steering is free now but this winter I will attempt a proper refurbishment of the Steering mechanism.