Force 85HP mystery HELP

[dayton2001]

Ok, took my boat out for the first time. 1989 Bayliner with a Force 1989 Motor. Bought this boat in Dec, It was missing alot of parts but finally got all the parts and got it running in the garage. Noticed that it was running a little rough in the down position but was ready to take it to the lake.

Got it in the water(stayed floating) test number one complete. Hard getting it started and staying at idle but with seem to warm up to being in the water after i put some sea foam(not sure if it really had anything to do with it. Floated off the dock went 3 or 4 miles at about 10 mph and seem like it wanted to dye ever once in awhile when I put it in nuetral or just had it trolling in gear. Finally found a place I could open it up at and it took off pretty well, come off the gas and the engine died.

This time i couldnt get it started again. Pulled the motor up out of the water and it started. Put it back in the water wouldnt start.

Used some STARTER FLUID and it stayed started in the water as long as I was putting starter fluid in the air intake.

So I payed for a tow(140 dollars) and an 1 1/2 wait for them to get to me and back on the trailer i put it. Started up great as soon as I got it home.

Motor runs great in the up position, runs ok in the down position. I ordered rebuild kit for the fuel pump and carbs today. Anyone have any idea what could be wrong. Why the great starting and idling in the up position but not so good in the down position. Im guessing it must be a fuel problem because of the starter fluid keeping it going while we were at the lake. Thanks for the help in advance. Im a little scared to rebuild the carbs as i have never done it before, but I have a manual and hope it keeps this amatuer out of trouble.

 

[dayton2001]

Re: Force 85HP mystery HELP

One more thing, Just took of the air manifold so I could see inside of the front of the carbs. Choke is in the correct position, with the motor in the down position, I choked the engine to start it, seems like it had some fuel(couple of drips) come out of each carb.

What does the choke do? when you close it does it some how suck fuel from the cards into the engine? I thought when it was in the closed position(choke on) it was shutting the carbs from getting air. But now i wonder if with the choke on it is suppose to suck fuel into the pistons to fire it up. Anyway, engine started for a second after I did that ran for about 10 seconds and died. If I choke it again it will start back up for a few seconds and then die again. Could all of this be a fuel pump issue? I pulled the hose of the fuel pump and seems to pulsate with plenty of fuel coming out of it while i am turning the engine over. Should this be a steady stream of fuel or is it suppose to pulsate as it is pumping fuel?

The more I work on this engine the more questions I have. Thanks for the help in advance. Derrick

 

[dayton2001]

Re: Force 85HP mystery HELP

Ok, more symptons for the experts. Started the engine in the up position, spriayed all three carberators while engine was running with carb and choke cleaner, didnt really make much of a difference, put the engine in the down position and while it is running it seems like it is missing every few seconds and then picks itself back up. As soon as I try to add fuel by using the carb pushing down on the throttle linkage it wants to dye, will not let me give it any gas.

With engine in the up position it will let me give it gas slowly but still is missing.

Im second guessing the fuel supply problem, everytime I put my hand over one of the carbs air intake it obviously wants to dye but the important thing is fuel comes out of the carbs for a second. Seems like it has plenty of fuel in the carbs?????????????????I think.

Hope this helps you experts. PLEASE HELP.

 

[TD_Maker]

Re: Force 85HP mystery HELP

I am not a Force expert by any means; however, it sure sounds like you have a float problem in your carbs. When you get your rebuild kits, be sure to change out the floats and clean each carb throughly. Just replacing the parts will not do the job.

 

[Frank Acampora]

Re: Force 85HP mystery HELP

First: STOP USING STARTING FLUID, CARB CLEANER, AND OTHER FLUIDS. They wash the oil off the bearings and cylinder walls. Continued use will cause engine damage for sure. Use ONLY 50-1 pre-mix as a starting aid.

The chokes act to enrich the mixture at start. Believe it or not, Gasoline has a narrow range where it will burn properly in an engine. When the engine is cold--even on a summer day, the gasoline does not vaporise well. This causes the gasoline vapors to be below the lower explosive limit and it will not burn. By using the choke, we close off the carb inlet causing a greater manifold vacuum. More gasoline is drawn through the fuel delivery circuits. The part of this EXCESS gas that vaporizes causes the gas vapors to reach the lower explosive limit and the engine will now fire and start, Continued use of the choke will cause the gas vapors to exceed the upper explosive limit and again it will not burn. The engine stalls and will not fire until the correct vapor level is restored.


Your problem sure sounds to me like you have an extremely lean mixture setting. Before you do anything else, set all three brass idle mixture needles at the top of the carbs to 1 1/4 turns out from a lightly seated position. This is our starting point, not necessarily the correct setting for the engine. With the engine idling in neutral, slowly turn each needle in 1/8 turn at a time until the engine speed which has been picking up, starts to drop off. That is the lean setting. Now reset to 1 1/4 turns and screw out each needle until the engine starts to run rough or stumbles. This may even be at 1 1/4 turns so work carefully and observe closely.

Now, set all three needles to the average between the lean position and the rich position--for example: If the lean position was 1/2 turn out and the rich was 1 turn out, set all three needles to 3/4 turns out. IN NO CASE ARE YOU TO SET THE NEEDLES TO LESS THAN 3/4 TURNS OUT. And 7/8 turns is safer. Too lean and you run the risk of detonation and melting pistons at higher RPM.

After you try that, then if you still have problems, come back.

 

[dayton2001]

Re: Force 85HP mystery HELP

Thanks for the help Frank,

First thing I did was set the idle s crews(I guess that is what you call them) all the way back to the in position. They were turned at about 3/4 turn out from the orginal position.

Set them at 1 1/4, and set the choke and the motor started up nice and quick. Turned them out to 2 1/2 and that is where the engine died. Turned them back to 1 1/4, again engine started up instantly. turned them into about 1/2 and it started running a little lean(I guess that is how you put it). If you could explain lean and rich. If it is running lean does that mean it isnt getting enough oil because it is a two stroke from the fuel. Or if it is running lean it isnt getting enough fuel?

Anyway, what was really noticeable to me was lots of smoke when I reaved the engine. I dont know if this is because I have the air intake off and it isnt recirculating the fuel back to the carbs. Isnt that what the hose on the bottom of the air intake manifold is for, to recirculate unused fuel?

Noticed that the engine seem to be running really well at the 1 1/4 turn area so I am going to leave it where it is. Take it to the lake and try to adjust in the lake to see if that makes a differnce since that is where I had my problem and I will do it dock side. I dont know if having the exhaust in the water is going to make a difference or not. Yesterday with the motor in the down position i couldnt give it any gas at all without it dying. With the screws set at 1 1/4 I give it gas and seems to respong pretty well.

This seems confusing to me,While I was at the lake a few days ago with the boat for the first time It ran ok for awhile at 5 or 10 mph, but was dying ever time I put it in nuetral or tried to just go at idle speed(just having the engine engaged in forward). But if I gave it a little gas it ran pretty descent. Then once I tried to gun it, and then let off it died and i could never get it started again unless I was using started fluid(Will never use it again Frank), Why wouldnt it have started again while at the lake and just idle or why would it start with the engine in the up position but not in the down. Im guessing the extra amount of energy the engine needed to put out with the exhaust in the water kept it from starting or I have something floating around in my carb or hose that when the engine is down it sometimes clogs something.

Problem seems that maybe it is intermittent or Im reading in to this to much. Also wondering if all the carb and choke cleaner I sprayed yesterday may have helped a little as well(Will never us again Frank), With the adjustent of the idle screws and the carb and choke cleaner was enough to fix the carbs. In the driveway the engine is purrrring pretty nicely and hopefull tomorrow I can leave work early and take it back to the lake and see if I can adjust a little better while in the water. Having it hooked up to the hose in the driveway sounds great at this point.

Frank, thanks for all your help since i have bought the boat. It is really helpful. Hopefully I will not be getting towed by anyboat anymore. Let me know what you think. Derrick

 

[dayton2001]

Re: Force 85HP mystery HELP

Frank, thanks for the help. took the boat out two weekends in a row. Ran great lots of fun. Ended up rebuilding the carbs. Good learning expierence.

Last time I had it out I broke the pinion gear on the starter. Dont know why it broke but maybe because it is old. Im ordering another tomorrow. Kind of wierd that it broke. But when I first bought the boat it was stuck in the up position, always connected to the flywheel. Greesed it and got it in the down position and it had been working fine since. Im wondering if the starter got stuck in the up position again after I started while at the lake, and broke the pinion gear from the stress.

Just wanted to say thanks for all the help from I boats and especially from Frank. Always answers my questions. Once I am done with the boat I will post some before and after pictures. Amazing how far it has come.

 

[jerryjerry05]

Re: Force 85HP mystery HELP

I have learned over the years that putting a canister fuel/water seperating fuel filter will help keep things in the carbs clean. Fuel stabilzers work!! Jerry