Very unhappy about my Siezed Piston '89 125 Force

[walkingfish]

Hello all,<br /><br />What im really after is a bit of knowledge, as it seems the damage has already been done!<br /><br />The Background Info<br />I have, as mentioned, an 1989 125 Force, and have been happy for 4 years, using info off this board my motors never missed a beat, until now.<br /><br />I had been out fishin all day, and as i was heading back to the ramp, at full throttle, i noticed what felt like a sudden loss of power, i slowed down to about half throttle, and it seemed fine. I gave it full throttle again, and after about 15 seconds it lost power again. This time i dropped back to about a quarter throttle and the motor stopped<br /><br />I took the cowling off straight away and felt the head, it wasn't so hot that i couldnt keep my hand on it, but it was pretty hot.<br /><br />I tried to start it again, and it refused to turn over, so i grabbed the fly wheel and tried to rotate it by hand to see why it wouldnt spin, and i could only turn it about 1/4 inch either way.<br /><br />I was stumped, and so sat there for about 5 minutes thinking about the problem, and then tried to start it again. And it worked, and sounded fine. BUT there was no water spray coming from the exhaust relief valves, so i shut it down, thinking that my impellor was shot and i had over heated.<br /><br />I came back in on the kicker, and the next day i took it into the local mechanic and asked him to do a compression test.<br /><br />The initial "thumb" pressure test showed that 3 of the 4 cylinders have compression, but one of the cylinders has NONE!<br /><br />I have left it up to the tech to remove the head ( all the bolts are siezed ) and inspect the damage.<br /><br />The Facts<br />- I hadn't used the boat for about 3 months.<br />- The fuel had no stabilizer in it.<br />- The impellor is 18 months old<br />- When i first started it, lots of water (more than normal) was coming out of the relief holes.<br />- It had run great all day ( not at full throttle )<br />- At one point ( 15 minutes before melt down ) i noticed some kelp around the leg, while trolling, and removed it.<br />- At full throttle it lost power<br />- It physically siezed, and could not be turned for about 5 minutes<br />- The head wasn't to hot just after it siezed<br />- It no longer pumps watter<br />- There is no compression in one cylinder<br /><br />The first questions i have in my unhappy, no boatin, saga, are the following,<br /><br />What can cause a motor to temporarily sieze?<br />What damage gets caused by it siezing, pistons/bore etc<br /><br />Any help, explanations, similar stories or the like, i would really apreciate reading them.<br /><br />So far im thinking that if im lucky i mught have to re bore, and replace one piston.<br />And if im unlucky, save for a new motor <br /><br />Thanx Team, sorry for the long winded approach.<br /><br />Brad<br />Invercargill<br />South Island<br />New Zealand

 

[walkingfish]

Re: Very unhappy about my Siezed Piston '89 125 Force

bumpty <br /><br />Any thoughts ??

 

[eurolarva]

Re: Very unhappy about my Siezed Piston '89 125 Force

Hoped someone else would have jumped on this one but because there are no takers I will give it a shot. You are sure you have the correct gas to oil mix. Because you are New Zealand the mix should be 20 ml oil to 1 liter of fuel. What do your spark plugs look like? If you have correct fuel to oil ratio but your carbs are burning lean you could still sieze the motor because the motor is not getting proper lubrication because of a lean condition. I like to see a little black oily stuff on my spark plugs so that I know they are not burning lean. It is possible that you plugged your water system and lost your cooling system. If this is the case you are going to have to back flush the motor out. <br /><br />I have a chrysler and on mine I can have water coming out the telltale and still not get water circulating through the head because it has a water bypass. If yours has a similar bypass another option is your thermostat was stuck closed and that would explain the excess amount of water you saw coming out. <br /><br />I would not take any of this advise to the bank but it may help you solve why yours went bad. If you fix it remember that you will need to run 24 to 1 on the oil mix after it is rebuilt for like 10 hours.

 

[walkingfish]

Re: Very unhappy about my Siezed Piston '89 125 Force

Thankyou eurolarva,<br /><br />I do indeed run the fuel/oil mix at 50:1 and use only the recommended (read expensive) TCW3 oil instead of just any TCW3.<br /><br />My plugs are a little black and oily, definately not clean.<br /><br />Interesting about the thermostat being stuck closed, never thought of that!<br /><br />Am i right in thinking that if it over heated, and siezed, and one piston has no compression, that ive done some nasty damage??

 

[eurolarva]

Re: Very unhappy about my Siezed Piston '89 125 Force

Could be. Could be as simple as replacing the head gasket. Compression testers are about 30 US dollars. I use mine on my lawn mower, snowblower and my boat. IF you are sure that the compression is bad on the one cylinder you should take the cover off and look at the cylinders and compare the bad one to the good one. I hope all you have to do is replace the gasket though.<br /><br />Good Luck

 

[walkingfish]

Re: Very unhappy about my Siezed Piston '89 125 Force

A bit of an update ! <br /><br />I have pulled the head off and there was scoring in the number 3 cylinder, i decided to remove the pistons and check it out.<br /><br />The News<br /><br />It would appear that one of the piston rings had broken, and slipped down beside the piston. This has left me with one shot piston and one cylinder that is scored.<br />Out of interest number 4 piston also had a broken ring, it just hadnt caused any damage yet.<br /><br />Intended Action<br /><br />It seems i will be re-boring No. 3 and putting in an oversize piston, and honing the other 3 cylinders and replacing the rings.<br /><br />The Extra Questions<br /><br />What causes rings to break, is it old age or something i did?<br /><br />Does my above course of action seem right?<br /><br />Is there anything else i should do while its apart?<br /><br />thanx,<br /><br />Brad

 

[eurolarva]

Re: Very unhappy about my Siezed Piston '89 125 Force

Could be a lean condition on your carbs. If you run lean the motor is not getting enough lubrication. Could be a bad water pump of thermostat so motor was not cooling. Is oil always mixed correctly? After you rebuild the motor make sure you run your oil at 24 to 1 for a couple of tank fulls of gas.<br /><br />Good Luck

 

[DJ]

Re: Very unhappy about my Siezed Piston '89 125 Force

walkingfish,<br /><br />One cylinder going bad is usually indicative of one of two things.<br /><br />1. Carburetion. Clogged jet caused lean condition.<br /><br />2. Excess carbon build up behind the rings. Force engines tend to run a bit dirty and decarb is an absolute maintenance must.

 

[walkingfish]

Re: Very unhappy about my Siezed Piston '89 125 Force

Further Update <br /><br />I have now found out that i will be needing to replace 2 pistons, it appears that the damage was coaused by crappy design in the "ring lands/grooves" i think thats the right term.<br /><br />Turns out that you cant buy standard size pistons for my force (gen. parts) but what does everybody think of Wiseco pistons?<br /><br />My tech tells me that it isnt worth spending the 3,000 estimated to fix this motor, but a similar motor to replace mine is about 5,000, and i dont know what the history would be.<br /><br />At least if i replace 4 pistons, bearings, and rings, surely i will have a happy Force?<br /><br />Im just hoping that shipping the Wiseco stuff from US wont be to expensive!

 

[dorelse]

Re: Very unhappy about my Siezed Piston '89 125 Force

Well, for what its worth, I had a similar issue with a 1990 Force 90HP engine. A ring broke, scored up a wall pretty good, and ended up being stuck in my piston head. It also apparently damaged an exhaust port by taking out a small chuck of it as well.<br /><br />I ended up taking a chance and buying a 1992 Force 90HP off of ebay for $1700.00. (Yes, it was a huge risk. It claimed to have low use, low hours, and freshwater use only.) Anyway, I called a couple references he provided, and it ended up being that he went to the same church I did a few years back. <br /><br />Long story short, I think it ended up costing me $2200.00 by the time I got the new motor mounted, tuned up, etc. I ended up selling the broken one for $700.00 on e-bay as well. It has been a great buy for me and has given flawless service for 3 years now. A rebuilt powerhead + all the labor & shipping would have cost me more. And the overall condition of this motor is far better than the one I had.<br /><br />Good luck.

 

[JGKoenig]

Re: Very unhappy about my Siezed Piston '89 125 Force

Just thowing it out there!! I am using Wiseco pistons in my 84 Chrysler 140 (bored 20 over) and have had no issues with them. I also know quite a few people that use those pistons in dirt bikes. <br /><br />I am a very non mechanical person and was able to completly rebuild my power unit with very few problems. You should be able to rebuild it for under $1000 (very high estimate) with boring and replacing all pistons. Get a Seloc manual. They seem to be the best. $3000 is way to much money in my opinion.

 

[Formula1974]

Re: Very unhappy about my Siezed Piston '89 125 Force

if the motor overheated it could sieze for a while when the metal expanded and then free up when it cooled down.

 

[vinney]

Re: Very unhappy about my Siezed Piston '89 125 Force

There is a problem in the block design. That engine almost all ways fails the number 3 hole. It looks like it crushes the number three piston. There were two blocks. The first one had solid webbing between the cylinders. The second they removed the solid webbing and put a hose in its place it routed the water flow thru the block. Once the block kills the number three hole. The block has been put thru many heat cycles and usaully not kill the number three hole again. You need to bore and hone all cylinders. I have cut the webbing out on the early block designs and put the hose in. Years ago we would rebuild one of those engines a week. Cast pistons only and watch your clearances.

 

[jayhay74]

Re: Very unhappy about my Siezed Piston '89 125 Force

I'm having a similar problem with my 88 125 force. However there are some differences it never seized and it seems to run fine except that it will only run at about 3/4 power and it will not get out of the water like it should. I know the coils are fine i havent checked the head gaskes or the cylinders for scoring. I was wondering if your experience with your motor would have any value in helping mine. Yours or anybodys imput would be greatly appreciated. <br /><br />Thank you for your time.<br />Jay

 

[DJ]

Re: Very unhappy about my Siezed Piston '89 125 Force

jayhay,<br /><br />Your performance problems are very indicative of having lost a cylinder. A compression test will tell the story.

 

[walkingfish]

Re: Very unhappy about my Siezed Piston '89 125 Force

things are starting to look up! <br /><br />Well im glad i used the net and ordered Wiseco pistons, from Pistons-Online.com.<br /><br />In $NZ <br />4 genuine pistons = $1600<br />4 Wiseco Pistons ex NZ = $1200<br />4 Wiseco Pistons ex US = $650<br /><br />You cannot imagine how much happier i am with finding these so cheap!!<br /><br />Does anyone know of a place online for Carb Kits?<br />What (If anything) can i do to prevent the rings from breaking again??<br /><br />Boatloads of thanks (as always)<br />Brad

 

[JGKoenig]

Re: Very unhappy about my Siezed Piston '89 125 Force

I use Fairwinds Marina, but their on line buying system stinks. They always seem to have everything (new and used), but can be a little expensive. www.fairwindsmarina.com<br /><br />This other site has been pretty good as well.<br />www.dougrussell.com. They have a pretty complete parts listing on-line. <br /><br />Carb kits are pretty easy to find. Even Napa (here in the US) carries them.

 

[JGKoenig]

Re: Very unhappy about my Siezed Piston '89 125 Force

Oh yeah, your other question. I have seen a synthetic oil for 2 stroke outboards that I have heard gives better protection even in a lean condition. May be worth looking into. I was thinking about giving it a try.

 

[rbruce63]

Re: Very unhappy about my Siezed Piston '89 125 Force

After overhauling with Wiseco pistons you will have improved the original design and no further problem could be expected. Do observe the proper oil ratio for breaking in the motor 24: 1.