85 horse evenrude boat motor

[kandiskay]

Help
I was given a 16 foot Bayliner with 85 horsepower Evenrude outboard on it. I know nothing about boats but want to learn. I am a woman with no one in my life to help me sooooooo that is whay I am here. I took the boat out and it would not run full throttle. It had been setting for several years but had only 50 hours on it I was told. Guess he meant it had been serviced.
Took it out a second time after having put stuff in it ....cem something.

After running it for about twenty minutes it opened up and would run full throttle
Then took it out again about 6 weeks later and it would not open up full throttle again, it would run only about half power again.
I again tried to run it for about an hour with no luck.I live in a small mountain town in northern Cal. and there is only one place to take it to be serviced but it costs so much $$$$$$$$$ to have it looked at.

Can anyone help me as to why is it doing this.It also came with another motor a 4 stroke Honda.... is all I can see that it says on it.
I have never had the Honda motor running as I do not know how to hook it up. Do I unhook the gas line on the big motor? and how do I steer it? it has a handle on it but do I hook up the steering from the big motor for trolling with the little motor. Please someone I really want to learn everything about my boat.

 

[F_R]

Re: 85 horse evenrude boat motor

You didn't mention what year that 85 is, so it's hard to give a good reply. A model number would be most helpful. But taking a shot in teh dark at it, I would guess it is not running on all cylinders. When the missing ones kick in, full power is restored. That could be caused by several problems, and determing which is the problem will take some diagnostic work.

Assuming your 85 is a two stroke, and assuming it takes mixed gas, you need another tank for straight gas without oil mix for your Honda.

Most people steer and control a "kicker" motor back at the motor, no forward controls. It is possible to position it straight ahead snd get some steerage effect from the main motor acting as a rudder. That main motor in the water also creates a lot of drag if you are trying to get anywhere significant with the kicker.

 

[fireman57]

Re: 85 horse evenrude boat motor

You said that you took it out after putting something in it cem something. Do you mean SeaFoam?
You could just have crud in your carbs that are clogging the high speed jet. Easy to take them off and clean them good. That being said welcome to iboats.

 

[emdsapmgr]

Re: 85 horse evenrude boat motor

A model number for the 85 would be most helpful. Most OMC/Bombardier outboards have a model number on the serial tag-located on the transom bracket or the swivel bracket. That area is below the powerhead, around the clamp bracket which holds the engine to the boat. Some serial tags are metal, riveted to the clamp bracket, others are a shiny vinyl label with the model information. Failing to find one, there often is a second model/serial stamped into the powerhead casting plug, located on the top of the block. See picture.

 

[emdsapmgr]

Re: 85 horse evenrude boat motor

An inductive timing light will help to determine if all cylinders are firing. The flashes from the gun will show the quality of spark. Good, intermittent, weak, not firing, etc.

 

[kandiskay]

Re: 85 horse evenrude boat motor

You didn't mention what year that 85 is, so it's hard to give a good reply. A model number would be most helpful. But taking a shot in teh dark at it, I would guess it is not running on all cylinders. When the missing ones kick in, full power is restored. That could be caused by several problems, and determing which is the problem will take some diagnostic work.

Assuming your 85 is a two stroke, and assuming it takes mixed gas, you need another tank for straight gas without oil mix for your Honda.

Most people steer and control a "kicker" motor back at the motor, no forward controls. It is possible to position it straight ahead snd get some steerage effect from the main motor acting as a rudder. That main motor in the water also creates a lot of drag if you are trying to get anywhere significant with the kicker.

The model number is 85493B it has four spark plugs in it so that is a 4 cylinder right? It does use mixed gas I was told 50 to one the stuff I was talking about that was put in it was called cemtool that is what helped it run better. It had been setting for some time I was not told how long but the way he talked it was a year or so. Thank you for any help you might give
Kandis

 

[kandiskay]

Re: 85 horse evenrude boat motor

You said that you took it out after putting something in it cem something. Do you mean SeaFoam?
You could just have crud in your carbs that are clogging the high speed jet. Easy to take them off and clean them good. That being said welcome to iboats.

Cemtool was the name or the stuff that was put in it that helped

 

[fireman57]

Re: 85 horse evenrude boat motor

There will be some here that will tell you to do a compression test first and that is not a bad idea but since you have had it running at full throttle and now it won't I would start with a good carb cleaning since it is something that you can do yourself and won't cost anything in parts. Take them off the engine and unscrew the four bolts on the bowl. When you take it off you will see just about everything. make sure you run a small piece of wire through the jets and take the float off and run a wire through the needle valve seat. Sounds hard to do but it isn't.

 

[emdsapmgr]

Re: 85 horse evenrude boat motor

1974 84 hp engine. I agree that a compression test is very worthwhile. Not much point in working on an engine which has bad compression. I would think the compression on that engine should be around 120lbs+ on each cyl. If an engine will run full throttle on occasion, it is likely the fuel system is ok. I just won't run full throttle if the carbs are clogged or the fuel pump is weak. Usually the fuel system either works or does not. The ignition is another thing. Weak ignition components may or may not work, usually on unexplainable intervals. If there are times when the engine seems to not be running on all cyls, remove the cowling and put the lead from an inductive timing light on each plugwire. The flashes from the gun will show you the quality of the spark to each plugwire. You may find one or more plugs are not firing.

 

[kandiskay]

Re: 85 horse evenrude boat motor

To do a compression test does it have to be running ? and if so does it need to be in the water when it is running? I used some cemtool t clean the carb and that is what helped when it started to run right.
That is what helped befor was the cemtool
should I get new plugs? It is hard living in a small town and not knowing anyone if I did I could ask for help here. I am thankful for everyones help here thank you

 

[fireman57]

Re: 85 horse evenrude boat motor

you need to remove the plugs and your compression tester screws into the plug hole. Give the engine a few good cranks and see what your gauge says. Then do this with the other plug holes. If some cleaner fun through your carbs helped just think what an actual carb cleaning would do.