1989 Force 85hp

Vester

Cadet
Joined
Jun 19, 2009
Messages
7
I have a Bayliner with a 1989 force 85 hp. I bought it a year an half ago and put it on the water three times. Now it will roll and roll and finally back fire. Then after if back fires and a try it again it will start with the choke and pulling the throttle handle out and pushing it forward. But when I put it to idle it dies. Sometimes it will fun for a second like it is not getting enough fire or fuel. I had a guy look at it and he said the compression was to low. He said it was all three cylinders were below 100. But all three carburetors have been rebuilt right before I got the boat and look really clean.

When I got the boat it ran fine the first two times I put it in the water. Then the third time we first put it in the water and it did not want to start, but finally did. later that day I ran out of gas and I think the gas that some guy give me was bad gas. If anyone can help I would greatly appreciate it.
 

john from md

Commander
Joined
Apr 13, 2008
Messages
2,184
Re: 1989 Force 85hp

First of all, we need to know what has been done to the boat as far as preventive maintenance. What is the actual compression in each cylinder? Have the carbs been overhauled, when? Has the fuel pump been changed recently? Does it have an internal tank? How old is the battery?

As you can see, you need to give us as much history on the motor as you can before we can figure out what you need. Most of us don't like shooting in the dark.

John
 

Vester

Cadet
Joined
Jun 19, 2009
Messages
7
Re: 1989 Force 85hp

The carbs have been overhauled, but I don't know when. The guy I bought it from said he just had it done and that was last may or so. I have not done anything to it because I really don't want to mess anything up worse than it is til I know what to do. the fuel pump is the one that was in it when I bought it and I the guy didn't tell me what the compression on each cylinder was, he just told me that they were all too low, I really don't even know what they compression is supposed to be one each one. I have a friend that can check them tomorrow. And yes it has an internal tank and the battery is new. If there is anything else you need just let me know and I can find it out for you. I just need some help on it. I am new to the boating thing and it is my first boat.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,196
Re: 1989 Force 85hp

Rebuilt carbs has nothing to do with compression.His tester might be reading wrong.The compression should be (with a GOOD tester)150#
If the tester is suspect then you look for a reading that is the same, say 120# on all three any more than 15# then there might be a problem.If the gas is old then there might be water in it. If it's new gas then the hoses might have taken a dump.Ethanol destroys the older hoses.I'd check that first,right after the compression test.You are mixing gas and oil together(just making sure)?
 

Vester

Cadet
Joined
Jun 19, 2009
Messages
7
Re: 1989 Force 85hp

Yes it is a 2 stroke, I have to mix the gas. I will check the hose. I don't know how to get to the tank tho. I might but I will have to look. there is a speaker in front of the motor close to the floor. I might be able to go behind it.?
 

john from md

Commander
Joined
Apr 13, 2008
Messages
2,184
Re: 1989 Force 85hp

Before you spend too much time and money needlessly, try something simple. Go buy a 3 or 6 gallon plastic tank and connector and connect that you your engine. If it starts and runs, you know that your problem is with the existing fuel storage and supply system. Ethanol is hard on internal tanks.

John
 

Vester

Cadet
Joined
Jun 19, 2009
Messages
7
Re: 1989 Force 85hp

can I just use a regular gas can or do I need a specific one?
 

azlakes

Senior Chief Petty Officer
Joined
Jul 8, 2007
Messages
720
Re: 1989 Force 85hp

When I got the boat it ran fine the first two times I put it in the water. Then the third time we first put it in the water and it did not want to start, but finally did. later that day I ran out of gas and I think the gas that some guy give me was bad gas. If anyone can help I would greatly appreciate it.

... start with the plugs. pull m, clean, replace them if completely fouled. save those for decarb. one day at the lake is enough to gum these up.
 

john from md

Commander
Joined
Apr 13, 2008
Messages
2,184
Re: 1989 Force 85hp

Well, if you have someone hold it, you can just take your fuel line off and put it into a gallon container. Just be carefull not to spill it all over the place.

John
 
Top