1989 85 hp force random dies and cuts out.

[bayliner_fox]

hello i have a 85hp force that has had its problems this year.boat didnt want to idle so had the mechanic clean the carbs.he then said he need to adjust the timing to make it idle. I thought it idle too fast so he then turned the timing down and adjusted the carbs.The boat still likes to die when you pull back to netural.(randomly). and it likes to cut out (randomly) when you hammer it.sometimes it would even die when you coming out of the hole. this is all random what i know is normal is the boat did do 45 Before and it would jump out of the hole and plane out faster then it does now. and now it would only top out at 40 no matter how many people are in the boat.good comp. something seems wrong. something must not be working 100%. any ideas would be nice. thanks for now

 

[john from md]

Re: 1989 85 hp force random dies and cuts out.

What is the rpm of the engine when it is in gear at idle? What is your WOT rpm? Have your replaced your fuel pump lately?

Do you have a manual and are you mechanically inclined?

John

 

[bayliner_fox]

Re: 1989 85 hp force random dies and cuts out.

yes i have the clymer force shop manual, The boat dosnt have a tach, Iam the process of tring to locate a 20 pole?, I belive i need one anyway. I know you can pump the ball to see if the pump is bad, but it starts right up and runs. Iam not sure how to check it other then that.I orderd new plugs ul18v i know that by heart. good to have on hand anyhow. we ran out on the mississippi saturday and the cut out and random dieing accured. about 41 is all i could get. and still slow out of the hole. thanks for your help. I should meantion it never cuts out other then when you first hammer it or when you pull back to netual then it dies (randomly)

 

[Frank Acampora]

Re: 1989 85 hp force random dies and cuts out.

Dying when put back into neutral is because the idle speed is too low. This can NOT be set by ear, and MUST be set in a test tank or on the water in forward gear to 700-750 RPM.

Dying when you accelerate from a stop--hole-shot-- is almost always caused by the carbs set too lean. This is dangerous and should be corrected immediately. Be certain the low speed adjusting needles are set to about 7/8 turn out from lightly seated and re-test on the water. Turn out 1/16 to 1/8 turn until the engine accelerates smoothly.

Correct running mixture will NOT be the best setting for a smooth idle. You simply can not have both.

After adjusting mixture for proper acceleration, then adjust idle stop screw for an idle at 700-750 rpm. You do NOT adjust timing to lower or raise idle speed.

Timing needs to be 30 degrees BTDC at full throttle, minimum of 28 degrees. Anything less and the engine will not idle correctly. Timing and carb opening MUST be properly synchronized for correct engine operation.

 

[bayliner_fox]

Re: 1989 85 hp force random dies and cuts out.

ok good info so should i start by getting a tach. figure out how to hook that up then adjust the front screws on the carbs to 7/8 out from lightly seated? then adjust the idle bolt to about 750? or where exactly should i start i dont have a timing light of any sort. i notice the idle bolt is attached to the arm that goes up under the flywheel. well i better head to bed but thanks againe. and how do i check the fuel pump?

 

[john from md]

Re: 1989 85 hp force random dies and cuts out.

First get a tach. Google tiny tach and you will be able to buy a small digital one which will work fine for adjusting the engine.

Set your carb mixture screws at 1 to 1 1/8 turn out for the time being. This is safer than running too lean.

All you need is a basic non advanced timing light. Sears sells them for $49, Harbor Freight has them for less. You will need one to keep this engine properly maintained.

The fuel pump is a diaphram under the fuel inlet strainer. It has six slot head bolts that come out to take it off. Don't check it, change it. They only cost about $7 with gasket on line.

www.iboats.com, crowleymarine.com, dougrussell.com, boats.net for parts and schematics. You must have your model number which is located on a plate in under the intake manifold.

John

John

 

[bayliner_fox]

Re: 1989 85 hp force random dies and cuts out.

ok iam going to try the process you mention . I notice my bulb doesnt get firm when you pump it .Looks like its original equipment. I should probably change that along with the fuel pump diaphram. I think i found someone with a shop tach to borrow. I was just wondering, what if i found a dash tach, how many pole would i need? i Heard 20 but a old timer crysler/Force guy said a 12 is probably what i need so i dont know.I will do as much as i can on the water hose.Then maybe go run at the lake.

 

[john from md]

Re: 1989 85 hp force random dies and cuts out.

For an 89, you will need a 20 pole. The newer models use 12 pole tachs.
You can do everything on a water hose except set the idle. That has to be done tied to the dock in gear.

John

 

[bayliner_fox]

Re: 1989 85 hp force random dies and cuts out.

ok here is what i came up with. I have perfect spark when the engine is at a idle. when i put the engine under a load i loose spark. on the bottom cyl. so now iam wondering what is causing it to just loose spark.

 

[john from md]

Re: 1989 85 hp force random dies and cuts out.

When you are advancing the spark, you are phyisically moving the trigger and the wires under the flywheel. It maybe that you have a wire that is making and breaking when you are moving the trigger. It also might be, if you have plug type connectors going to your CDI modules, that the trigger movement is pulling the plug apart. I have seen this happen in older engines as the plastic on the plug shrinks and they don't stay locked together. I have tied mine together with tie wraps to prevent this from happening.

John

 

[moparman]

Re: 1989 85 hp force random dies and cuts out.

you might also want to look at the wires where they come under the flywheel for chaffing[wearing the insulation away]as this would let them short to ground

 

[bayliner_fox]

Re: 1989 85 hp force random dies and cuts out.

ok i think i found a bad cd box, i tried the other side it was already bad. so got a new box, put it on runs top speed now. Idle seems alittle high is there anyway to set the idle without a tach? I know there is a set bolt on the arm that goes under the flywheel is that where to set the idle? and if i set the idle will that effect how the timing and carbs are set or do they all need to be set accordingly? It runs great now just wish the idle was toned down some. thanks for your guys help, Iam just a regular guy from iowa working for the weekend.

 

[john from md]

Re: 1989 85 hp force random dies and cuts out.

Buy or borrow a cheap inductive tach used for tuning cars. You can even find them on ebay. There is no way to set up this engine without a tach; no way.

John

 

[bayliner_fox]

Re: 1989 85 hp force random dies and cuts out.

tach is my next step. it idles alittle high but dosnt clunk going into gear so i might just leave it alone ,tell i can get either a shop tach or a dash tach.

Is the tach wire the gray wire? where is it?

 

[john from md]

Re: 1989 85 hp force random dies and cuts out.

The tach feed comes off of the rectifier on the left side of the engine. You can also access it from the engine terminal board.

Finding a 20 pole in dash tach is not easy anymore. Most tachs now operate off 8, 10 or 12 pole alternators. You may want to look into a tiny tach. It is a small digital unit that you can mount on the dash but it is only about an inch wide. I have one on several of my engines and they work well.

John

 

[bayliner_fox]

Re: 1989 85 hp force random dies and cuts out.

ok here is a quick update. took the boat out today . Boat started right up. still had a slight high idle all day. I really cant do much about that intel i get a tach system installed. Another reason i think that the idle is high is it will clunk alittle when shifting gears, so now iam going to try to find a tach i checked out the tiny tach. but i was hoping to find a matching tach and speedo combo that will work.