'85 Force 85HP No compression

[jubjub]

I have a Force 85 on a 85 Bayliner. <br />This is a recent buy. I used the boat four different times.. no problems... Last time the boat ran fine one day. The next time it would not go to full plane. I replaced the plugs... Ran fine....Then it shut down will running at full throttle... I took it in the compression was 125/50/125<br />This mechanic first said 300-600 on repair. Now I'm being told by shop owner it will be 1200. What is the norm for such a repair? Also he says parts are rare and high. What is a good site or place to find reasonably priced replacement parts?... considering it is just the piston assembly or just rings...Do all 3 piston and rings need to be reworked or only the one....<br />I appreciate any and all response.<br /><br />"Feel like I bought a lemon"

 

[G DANE]

Re: '85 Force 85HP No compression

Hi JubJub<br /><br />Before you throw your towel in the ring, try to find the reason for the compression loss.<br /><br />If your luckey, a blown gasket can be the reason. ( 50 $ )<br /><br />What did the plugs look like ? Did you have a clean plug in the bad cylinder - a very clean plug is usually a sign of blown headgasket.<br /><br />If you´r handy with tools, try to remove the cylinderhead and take a look at the cylinderwalls and piston.

 

[jubjub]

Re: '85 Force 85HP No compression

GDANE, Thanks for your quick response....<br /><br />The plugs I had in it when the major shut down happen were new and upon pulling them they were coated some and moist....probably due to the choking and continued cracking. The engine had set for 2 years prior to my purchase. The last time I tried starting it, I had to start with the trottle engaged slightly, but it would not idle in neutral position. Once it started I had to go to full throttle. It went about 3 hundred yards and shut down. I didn't get it started after that . The plugs looked about the same everytime I pulled them.... All Three...outwardly the engine shows no oil signs. Very Clean for the age....

 

[G DANE]

Re: '85 Force 85HP No compression

Hi again Jubjub<br /><br />I think you are dealing with two problems.<br /><br />One: You really need a carb clean/rebuild. The reason you cant start is because you have gummed up carbs after the motor sat, or carbs are flooding because of stuck needle valve, or fuel pump not pumping. I had a two cylinder which didnt run on one cylinder at all due to broken reed on one cylinder, started every time though. It sounds like your motor is starving for fuel = clean carbs.<br /><br />Thats probably the reason for the shutdown experience, old gum floting around in fuel system, or maybee the fuel pump diaphrame has gone bad - try to squirt fuel directly in the carbs and do a test startup. ( with cooling of coarse ) <br /><br />Two: I guess you had the low compression from you bought the motor, it just ran poor on that one. give it a try. If you get it started give the motor a decarb threatment. It is not unusual a piston ring gets stuck efter motor sitting long time without winther preparation ( not only for winther )<br /><br />Decarb can loosen ring, and your motor will be ok again. i would wait with pulling head till then.

 

[jubjub]

Re: '85 Force 85HP No compression

Hi G DANE,<br /><br />I have pulled the bowls off the carbs prior to this last outing...plenty of fuel in the carbs...<br /><br />The starting has not been that bad prior to the last time I went out , however the sudden shutdown was new to me. I had planned on decarbing to see if it helped the starting before the last incident. <br /><br />I have tubbed and ski both behind the boat prior to all of this....it pulled fine...and I'm not a small man by no means...<br />I am going to pick it up this weekend a see what I can find out....<br /><br />Thanks for your replies...I'll let you know what I find...<br />Have a good weekend.

 

[G DANE]

Re: '85 Force 85HP No compression

Hi again Jubjub<br /><br />Having plenty of fuel in carbs tells you fuel pump is working.<br /><br />I am not familiar to force carbs, bot on JohnnyRudes the important is that the jets are PERFECTLY clean. And it is in the jets, both the brass high speed jet, in the bottum of the bowl, and in the iddle and intermittant jets, forged in top of carbureator body, old fuel varnish will block. If gas/air mixture isnt proper your motor will run very bad, and have hard start. The three cylinder is known for almost perfect iddle, even at two cylinders. I would pull carbs, and clean every passage and jet - try to find everything, very carefully. Use carb cleaner and a small wire for the iddle/intermediate jets. Bet it runs again, but with a week cylinder. Then try to do a decarb threatment.

 

[jubjub]

Re: '85 Force 85HP No compression

GDane,<br /><br />Well, got the boat back home.<br />I went ahead and pulled the head. The middle piston which had 50 compression is smooth accept near the exhaust ports. Looks like all three have normal scuff or coating slightly on the botton side of the cylinder. <br /> <br />I let you know more as I progress.<br /><br />Thanks again for the info.<br />If I can locate all the parts I may just rebuild the carbs too.

 

[FORCEfull]

Re: '85 Force 85HP No compression

Let me know if you are looking for a used motor I have a 85 model 85 horse. 120 to 125 compression on all cylinders. I have had a problem getting the ignition to fire on all cylinders...and I am about ready to throw the towel in on this thing.

 

[G DANE]

Re: '85 Force 85HP No compression

Good to hear JubJub<br /><br />At least it seems like you have no major failure.<br /><br />I think a real carefully carb clean, new headgasket, and a decarb threatment, and you will be going better than before !!<br /><br />Now your at it, check and clean all filters in your fuel system. When bowls are off carbureators, turn them upside/down ( dont loose anything ) and see if floaters rest equally in hight.<br /><br />When you go to a shop and calls for estimate, they often consider some lager repair, they dont want so give a too low estimate, and of coarse, they want to make money too. Do you have a torque wrench for the head, otherwise borrow one. Dont for get to returque after first run, i think you will be fine, and you saved your motor.

 

[jubjub]

Re: '85 Force 85HP No compression

GDane,<br />Well after taking the exhaust plate off I discovered that the bottom 2 pistons are scratched about the same.<br />the rings are worn so they are hard to see separate from the piston. I've located a guy that is going to help me work through it all and has good experience himself. He looked at it today and said it is best to bore all three since I have it broke down. I'm starting to tear it apart. I am probably going to go through the carbs and powerhead since I have someone available to personally assist. Thanks for the good advice. It will be several weeks before I get it done. I 'll let you know about the final outcome.<br /><br />JubJub

 

[G DANE]

Re: '85 Force 85HP No compression

Hi jubjub<br /><br />Sorry to hear. Be sure you get the carbs rebuild. Tha question you have to ask is : Why did it happen. Usually things like that happens due to overheating, or lack of lubricating, caused by wrong, or no oilmix, or lean gas/fuel mixture, causing low lubricating and high combustion temparature. Overheating should be before your time - but better check impeller and thermostat, and passages in cooling system for old impeller fragments, be sure to clean carbs, so each cylinder get the right micture, its common jets gets a little blocked when a motor has been sitting for a while. Remember they are measured in hundreds. You will end up with much more power, especially hole shot, and a better economy. Good luck

 

[G DANE]

Re: '85 Force 85HP No compression

By the way:<br /><br />thy to shop a little around for pistons and I hope you will get a good deal.

 

[jubjub]

Re: '85 Force 85HP No compression

GDANE,<br />Got the powerhead off and broke down.<br />I'm leaving the pistons in til I get to the machine shop.<br />I figure they might need all that any way. I wasn't to bad tearing apart. Snapped a couple of bolts, but I'm going to try to use an ease out on them. One is on the housing and the other on the exhause plate. I'm talking to machine shop next week. Hopefully I can have in together in a couple of weeks or sooner. I picked up chemtool part cleaner bucket today. Probably tackle one carb tommorrow. Your probably right on the overheating. I 'll change the impellar also, might as well considering I'm going to the expense on the other stuff.<br /><br />Take care.<br />Jub

 

[dmessy]

Re: '85 Force 85HP No compression

You don't have to bore and replace all 3 pistons, just the bad one. I had Force 75 that semi -ceased the top piston. I had to go .040 over with a new Wisco piston on that one and just lightly honed the remaining 2. I reinstalled the original rings in those 2. Check your clearances on the good cylinders, if in line, save yourself approx.$100 per piston plus the cost of the additional machine work. <br />That motor is still running strong 2 years later.<br /><br />PS-the .040 piston is not any heavier than the stock so don't worry about the mismatch. Also , my total cost of repair when I did the labor(other than the machine work,$50) was under $300!

 

[happyzee]

Re: '85 Force 85HP No compression

BTW, Did YOU ever recheck the compression? I find 125/50/125 interesting. Especially after you seeing nothing strange after pulling the head. Hmmm A lot of mech. seem to have something against Force Engines.<br /><br />Ken

 

[jubjub]

Re: '85 Force 85HP No compression

After getting into the block. I found that two of the three needed work. The lower two pistons had wear to the point that the rings couldn't be detected from side view.<br /><br />I also found that the "I believe it called" the block bypass plug or something like that had sand or deposit solid in the bored channel at the end SOLID.<br />This probably caused a overheating problem prior to my purchase and I worsened the problem. <br /><br />I getting the cylinders for $30/hole and the rebored and tap on the broke bolts for $40. I guess that good.<br /><br />jub

 

[CraigO]

Re: '85 Force 85HP No compression

FORCEFUL,<br />How much are you wanting for your 85 HP Force Outboard?

 

[kevin carter]

Re: '85 Force 85HP No compression

G DANE,<br /><br />I was interested in reading your reply sugessting changes the reed plates. I also have a simular problem, I recently rebuilt an 85 HP Force motor that sat for many years and now the motor will only run at higher rpm's and dies at idle speed. You stated changing the reed plates, would that the reeds for each carb or just the reeds for the fuel pump.

 

[G DANE]

Re: '85 Force 85HP No compression

Forced, my motor sat for a couple of years too, but i dont think this was the reason.<br /><br />One of the reed leaves simply broke off. The first time i went under WOT or 80 % of max rpm, the motor lost 75 % of its power. It could only iddle when I was playing with throttle, but I am told a 3 cyl will iddle fine, and be able to accelerate, only poor. You only need to change the bad leaf, but I changed both, and I will advise anyone to change all, they work equal.

 

[G DANE]

Re: '85 Force 85HP No compression

By the way, JB got mee on the track to this error. I had normal compression and spark, carb was fine. No signs of other errors. He advised mee to pull the spark plugs one at a time and detect in I had a non running cylinder - good advise !!!