Smokey 85HP Force(1985)

[1650CC]

I have a 1985 85HP Force that has a smokey and very STRONG smelling exhaust. I have rebuilt the carbs, replaced the fuel pump gaskets, cleaned the puddle drain fuel recirculation system, and have run ring cleaner through. Compression is @ 130-135PSI uniformly on all cyl. Plugs are wet with some black carbon. When engine is accelerated it misses a little and leaves a smoke trail for a few seconds until it clears and then seems to be running great. I have the correct prop and am getting 5300-5450 RPM at full throttle. The engine runs great at cruise power but quickly begins to gag everybody after a few minutes at idle speed. I have adjusted the carbs as spec. in manual. I have also noticed occasionally that one or two of the carbs mixtures can be set all the way in and the engine will sill idle without popping and then quitting.(screws are not dented and have not been torqued down). This has been an on going problem and I cannot seem to get the problem resolved from local experts without replacing the engine. If anyone can help me I sure would appreciate it. Thanks.

 

[johnkc]

Re: Smokey 85HP Force(1985)

1650,when you changed the fuel pump gaskets ,you also changed the diaphragm didn't you ?because a hole in the diaphragm could cause this problem

 

[Backlash]

Re: Smokey 85HP Force(1985)

 

[Backlash]

Re: Smokey 85HP Force(1985)

Hey 1650,<br />Sounds like the oil/fuel mixture is too rich on the oil side. Try disabling the VRO & run 50:1 premix....see if it makes a difference. If so, the VRO is the culprit. If not, well at least you've eliminated one possibility. <br />Backlash

 

[DJ]

Re: Smokey 85HP Force(1985)

1650,<br /><br />Your Force does not have VRO (oil injection). Suspect JohnKC is on to something.

 

[Backlash]

Re: Smokey 85HP Force(1985)

Duh....another senior moment. Sorry to have confused the issue. No VRO to worry about.<br />Backlash

 

[ODDD1]

Re: Smokey 85HP Force(1985)

Listen to John...if the fuels is not getting in the motor thru the carbs, the fuel pump is first suspect....

 

[1650CC]

Re: Smokey 85HP Force(1985)

I did replace the Fuel pump diaghram. The old diaghram appeared to be in good shape. I did not see any holes or rips. I will probably test run it again tommorow to see the results. The gas in the tank is several months old, what type of problems might I experience with gas that old? Or, is that not too old? Also, would 89 octane help? The exhaust smell while idling is really strong smelling. While moving at idle speed it back drafts, and really smells strong of unburnt/not properly burnt gas. Thanks for your replies.

 

[petryshyn]

Re: Smokey 85HP Force(1985)

>Does it idle smooth? <br />>can you make it stall at idle by squeezing the primer ball hard? (high float level or leaking float valve can be evident and aggrivated by high fuel pressure)

 

[johnkc]

Re: Smokey 85HP Force(1985)

1650, schematic has a good point , the float level.is it level?and do your floats have those tiny little fn springs on them ? when trying to fix a problem of this nature i would start with fresh fuel, you should be ok with 87 octane.and have you ever ran it with out the hood on ? the reason i ask this is because the exhaust tube at the back may have a split in it letting exhaust under the engine hood making it act like a flood {less fresh air to burn}

 

[my new fishmaster]

Re: Smokey 85HP Force(1985)

Weak ignition will cause this as its not building enough spark.

 

[sony2001]

Re: Smokey 85HP Force(1985)

By the book is the timing at 32 degrees before TDC? My idle mixture screws are only 1/2 turn out. Common fault is setting carbs mixture screws with idle speed screw still engaged. Yes, could be your problem!

 

[1650CC]

Re: Smokey 85HP Force(1985)

I checked the timing recenctly, and it appeared to be correct. I am not sure i understand what you mean by "idle speed screw still engaged"(Sony2001).<br /><br /> I have not yet checked out the ignition system. I had the trigger and stator replaced three years ago. Is there anyway I can test it?(My new Fishmaster)<br /><br />The floats are set correctly, I checked them out already. But I have not yet tested the primer bulb while it is running(johnkc & schematic).<br /><br />I really appreciate your responses and will keep trying new things till I get it fixed. Look forward to hearing all ideas!!

 

[johnkc]

Re: Smokey 85HP Force(1985)

1650, make sure that the throttle plates are synchronized and completely shut at idle.{idle speed screw question} and on your ign ,spark should be able to jump 7/16 inch gap on all cyls.1/2 if you are lucky. did your floats have the springs on them that the float pin went thru?and if i remember corectly are the idle mix. screws at 3/4 to 1 turn open?

 

[sony2001]

Re: Smokey 85HP Force(1985)

1650CC on the left side of carbs there is a TOWERSHAFT to which the Throttle Link Rod is connected. Within an inch there is a screw with locknut that buts up to the engine block. It must not be butting when you are setting the carb mixtures to around 700 rpm. After they are set, use the SPEED SCREW to raise the rpms to 900.

 

[petryshyn]

Re: Smokey 85HP Force(1985)

I don't like the idea that it continues to idle with the idle mixture screws are turned in all the way. That means fuel is getting in from places other than the idle circuit. The most common offender is the fuel pump. Squeeze the primer bulb hard while idling, and see if it affects idle speed. This would ofcourse aggrivate the problem and give you some direction.<br />If this proves to be OK, the float level could be high. Not necessarily due to adjustment, but because of a leaking needle and seat (crap in needle and seat or defective parts) To prove this:<br />>shut down engine<br />>squeeze primer till hard, then hold steady pressure on bulb.<br />>does bulb slowly go soft after a minute or two?(it may take awhile) If it goes soft, it can mean other leaks as well, but it'll give you some direction....<br />>If you maintain a stiff primer for a few minutes and fuel starts dripping from carb, the needle and seat need checking.....<br /><br />good luck!