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1987 Johnson 225hp rough start won't accel

J

JohnBerling

New member
Hello, I have a 1987 Johnson 225 VRO that I got back from a local repair shop after they gave up on it. They put 6 new carburetors and coils on it, drained out all the old gas, replaced all the fuel filters, put 6 new Champion QL-77JC4 spark plugs in it, and replaced the battery.

They also tested the fuel pump and the engine compression: 80-85-85-78-81-84

When I picked it up, they said it would start, idle, and idle in gear, but wouldn't throttle up in gear.

Since they were stumped, and the compression was so low, I didn't want them chasing it any further, so I took it out on the water to see if it just needed to RUN (it had been sitting for a few years - don't know how long).

I read (on this forum) about a starting procedure for this engine that has made a big difference in getting the engine started when it's cold, but I still have the following issues:

Engine idles VERY rough in neutral, but idles and revs very well when the throttle is advanced in neutral.

Putting the boat in gear without it stalling takes jerking the throttle from revved in neutral, to neutral, then jamming it into gear before the rpms drop too low (obviously bad for the gears!).

At true idle speed (no wake),the engine will stall within a minute or two, after which it is very difficult to restart.

To get up on plane, I have to hold in the (primer pump) key until I get above about 3000 RPM. Once it's up and running, I can throttle up to 5500 (haven't pushed it to WOT), or back down as low as 3000 without any problems. The engine sounds good in this range.

If I slow back to idle speed, the now warm (not hot - can still touch the head) engine will stall right out, and restarting the engine takes anywhere from 1-2 HOURS of trying.

Other info: The bulb never gets really hard, and the sight glass inline after it does not stay full. Even with fuel showing, the bulb will go soft again within a few seconds. Pushing in the key drains the sight glass. Sometimes the bulb will be firm, but there is no fuel in the sight glass, as if it is full of air under pressure.

The shop I used was not a Johnson service center (we don't have one within a few hundred miles), but they didn't seem like crooks - called before every part and trial, and returned all replaced parts to me.

So, we're both stumped - any suggestions???

Thanks,

John
 
Re: 1987 Johnson 225 rough start won't accel

Additional information: All the wiring and fuel lines were also replaced. I have made sure all the hose clamps are tight.
 
Re: 1987 Johnson 225 rough start won't accel

How about pumping the fuel bulb when trying to get up on plane see if that works.because by bumping the choke to get it up on plane it seems like a fuel problem, but with the comp numbers so low I don't know. have you tried using seafoam to decarbon the motor and see if you could free up the rings?
 
Re: 1987 Johnson 225 rough start won't accel

Thanks for the reply. I have had someone check the bulb while throttling up, and it was soft - pumping it didn't seem to have any effect. Yes, the service center did a decarb. Thanks again.
 
Re: 1987 Johnson 225 rough start won't accel

Please do a spark test, you may be looking at a faulty stator or trigger, Use a flash light and peek up under the flywheel you are looking for melting sticky glue like stuff, if present chances are you need to pull the wheel for a detailed inspection and replacement.
 
Re: 1987 Johnson 225 rough start won't accel

I checked my paperwork from the service place, and they indicate spark and stator were checked - no numbers given. Apparently, they didn't like some portion of the electrical tests though, because they replaced all the wires and coils.

They also replaced a charge coil and charge coil assembly.

I looked under the flywheel several times the other day and didn't see any sticky goo, but I wasn't looking for it either, so I'll check that area again.

The compression numbers are in my original post: 80-85-85-78-81-84

Thanks for your help!!

John
 
Re: 1987 Johnson 225 rough start won't accel

If it were mine I would try a new 6 gallon fuel can with new fuel line and bulb assembly directly connected to engine & see if problem goes away. The "push in the key drains the sight glass" makes me think fuel issue.
 
Re: 1987 Johnson 225 rough start won't accel

That was a good idea, and I tried it, but it didn't make any difference.

So much for that C-Note experiment!!

Also, no goo under the flywheel, but thanks again for the suggestion.

At this point I suppose my biggest question is, do the low compression numbers make this an engine no much worth trying to resurrect?

Thanks again - John
 
Re: 1987 Johnson 225 rough start won't accel

The compression is on the low side. It sounds like you've already invested quite a sum trying to resurrect that motor. My understanding from your post is that they put on new carbs & tested the fuel pump. I still suspect the fuel pump as a probable cause of your troubles. Do you know how the shop tested the fuel pump?
 
Re: 1987 Johnson 225 rough start won't accel

If the primer is draining the in-line filter, I still believe you have a fuel supply issue. Can't believe the 6 gallon can didn't cure it. Fuel pump tester is easy to rig. T-fitting in the line to the engine, basic automotive type vacuum/pressure gauge connected in the middle. Don't know what numbers you should be looking at for your engine, but if the pressure is drops substantially when the problem occurs, that would be helpful to know.
 
Re: 1987 Johnson 225 rough start won't accel

I have an '88 60 horse, 3 cyl. and had this exact problem. I had 70, 120 and 130 for compression. Found broken piston ring in low compression cylinder - lots of damage too. I would guess your low compression is the idle problem. Perhaps bad gaskets, warped head, valves - something interior and not neccessarily fuel. It maybe wouldn't hurt to try a different compression tester.
 
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