When our 125 eats a piston

[tommarvin]

I am learning so much so fast,because of everybody that's writes something, a big thank you everybody here, Hey when our Force 125 eats a piston, can I hone it out to .010 over, install a wiseco piston, and get back to crabbing, during our two month summer crabbing season here on Puget Sound? Thank you !

 

[fhhuber]

Depends on the damage caused when it "ate" the piston...

Just a hole in the piston means there is debris that needs to be cleaned out.

There may or may not be damage to the cylinder walls and it may not even need the cylinder honed... or it may be severely gouged out and need to be bored and sleeved.

Then there's the other damage which could be caused by the bits of metal rattling around in the engine.. destroying bearings, getting at the other cylinder(s)... and potentially trashing the whole engine.

This is simply a question that can't be answered with out pulling the engine almost completely apart and looking.

 

[Frank Acampora]

What makes you think your 125 will destroy a piston or two? While it is true that the semi-keystone rings do have a tendency to catch in the exhaust ports, it is by no means a certainty. Many Force engines run for years without breaking rings. AND if you keep oil at 50 to 1 and don't set the carbs too lean the engine will run very happily for you.

Even if it does break a ring this usually does not do tremendous damage and sometimes if the cylinder is not badly scored the piston and rings can be replaced through the reed opening without dismantling the engine, with a simple honing to break the glaze.

 

[Jiggz]

Frank said it quite frankly. But if it does happen and the scoring is not bad, yes you can replace the piston and even hone it over but only if it does not exceed max specs. There are too many variables to mention but ultimately you would like to prevent the casualty from happening by maintaining her correctly.

 

[tommarvin]

Thank you, we think we do perfect maintance can we do better,we only use 100% synthetic, marine two stroke oil, marine gear lube, tested with 10% water contamination and marine fogging oil. Is spray fogging oil the best, we can do, ten seconds in each carb, five seconds in each cylinder, with the piston all the way in before you spray Yam has a product called Yamalube- EFI engine storage fogging oil, one quart in two gallon gas can, put a wye close to engine wine a piece of fuel line going into the two gallon gas can fogging oil mixture. For example, we use our boat every weekend, I wish, when we are done Sunday night, we do one of the the two fogging oils, spray or in gas or will 25:1 synthetic two stroke work the same run for five minutes until Smokey turn off motor, The yam fogging oil is a petroleum base product,we would rather not use. Lube the motor every weekend, to extend engine life, the rings, and not dry starts on Saturday morning. Time or money are not a factor .What is perfect

 

[jerryjerry05]

Take a breath between sentences.
​Kinda hard to read like this.

No need to fog the motor each time it's shut down.
If the fuel system is functioning right the residual oil should be enough to prevent dry starts.

The more oil or anything you add the motor has to burn it out.
It's more than likely gonna gunk up and turn to carbon on a ring and then eventually it'll cause the ring to seize.

Just using it on the weekends should keep it lubed.
Additives like Sta-bil or Seafoam aren't really needed unless you let it set for a long time.

Leaving the tank full is one of the best things to do.

IF???? You keep the recirc system and the carbs set right and do an occasional decarb(once a year),
flush after each use in salt water,your motor should last a long time.

Trying to hone out .010 over is a LOT of honing.
IF?? there is a damaged piston then a bore out and complete disassemble is needed(my opinion)

 

[Frank Acampora]

As jerry said, you can not hone to .010 over. It Must be Bored, Honing is a finishing operation meant to remove only about .0010 material or to break the glaze that develops on cylinder walls to aid new piston ring sealing.. If you try to go .010, you may be able to do it but you WILL barrel shape or egg shape the bore.

Also agree with jerry that you are practicing overkill on the fogging. Even though you are using the engine in salt water, fogging is only a long term storage procedure. You should pay attention to rinsing the engine on muffs with fresh water after each outing and lubricating the kingpin and swivel points. Also rinse off the power tilt/trim

 

[Nordin]

Agree with jerryjerry and Frank, do not over maintain. If you boating in saltwater and trailing it, flush the engine with freshwater after each time.

To much maintaining with lube, oil and fogging will kill the engine faster then keeping it in good shape.

Use good TCW-3 two stroke oil (remember it is not better more expensive it is) ratio 50:1, lube greasefittings with good marinegrease every autumn. Empty the carbs every autumn and if your fuel contain much ethanol put stabilfluid in the tank.
Check and change if needed the waterimpeller every 3-5 year.
And the most imported thing, CHECK and change if needed the gearcase oil every autumn.

One other imported thing too that will last the engine longer. Remember that it is about 20 years old or more (depend on year, do not see it in the thread).
Ride it with care, do not use it in WOT for hours and give it time to cool down now and then. Use WOT sometimes and riding in 3/4 of WOT is much better and will save money.

 

[jerryjerry05]

Oh yea: the kingpin area has grease fittings.
​If they haven't been lubed the lube in there can turn hard and the adding of new grease will push the fitting out.
They are pressed in and a little bit of back pressure they will pop out.

I used a small propane torch and heat the area and then slowly add grease.

Too much heat and the bushings at the top and bottom will melt and seize.

I ended up adding extra fittings. Salt water is really tough on Force outboards.
They weren't really designed for anything other than fresh water.

 

[tommarvin]

I just found the kingpin, we pumped marine grease in until we saw new grease at the top of the kingpin, the middle spot, but no grease at the bottom of the kingpin cap area.

I can put my small finger tip in the bottom end of .the kingpin. It shows part #500707 cover shock mt. lower, covering the bottom of the kingpin, do we need that part ? Thanks

 

[Frank Acampora]

The bottom of the kingpin on all Force engines is open. The kingpin is a hollow steel tube with a plug at the top where it is secured to the lower cowling. It is a very heavy walled tube and even though water gets into it and it rusts quite nicely, if you keep it lubricated so it does not bind in the swivel yoke, it will last the life of the engine.

I did replace the kingpin on one of my engines with a solid aluminum bar. It was very expensive to get the correct strength bar and since the 1 1/2 inch diameter bar was very slightly greater in diameter than the original kingpin I needed to ream out the bushings. All in all, it was not worth the extra cost and time involved.

Because of the location of the grease fitting, grease preferentially oozes out the top. You do have the option of adding a grease fitting to the bottom of the swivel yoke but in my experience, if you keep the yoke greased, enough will work down to the bottom to keep it from seizing.

I do not look up part numbers but if the part you are describing has four bolts securing it. then it is the kingpin cover and holds the pin to the front cover in addition to securing the swivel yoke to the lower motor mount. Do not try to remove this cover for no reason. The bolts do seize and it is highly likely that you will snap at least one during removal.