1988 Johnson 150/ran at home but not at ramp.

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

I did run on fuel mix.I dont think i could foul out a brand new set of plugs in10 minutes do you.

 

[emdsapmgr]

Re: 1988 Johnson 150/ran at home but not at ramp.

90 lbs compression should be just fine. All 6 plugs should wind up looking the same, so if two look different, something is going on. You may want to check the ignition. When you get it running in the driveway, let it warm up for 15 minutes, then put an inductive timing light on each plug wire and see if all 6 are firing the same.

 

[dannyman3]

Re: 1988 Johnson 150/ran at home but not at ramp.

I did run on fuel mix.I dont think i could foul out a brand new set of plugs in10 minutes do you.

if it was running to ritch it could have fouled them doesnt take long

 

[CharlieB]

Re: 1988 Johnson 150/ran at home but not at ramp.

With the engine OFF, set the control to WOT in Forward gear.

Remove the airbox cover and while watching down the carb throats pump the primer bulb and look for ANY fuel. The floats, needle and seats should seal and NO FUEL should be visable. Make sure that the engine is trimmed and the carbs are level.

If any fuel then get back into those carbs.

90 PSI compression or less can be suspect, depending on the year/model of your motor or the quality of your guage. As long as the pressures are consistant then it should not be the problem, all cyl's should burn the same.

What spark plugs are you using? The OEM specified Champions?

 

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

I hope i am learning here. I did a spark check on all cylinders and the bottom left is not getting a good reading.Its the only one out of the 6 /bad reading when it skips.Hope i am getting somewhere.Bad coil i hope.Getting a new one tomorrow.What do you think.?????????????/

 

[iwombat]

Re: 1988 Johnson 150/ran at home but not at ramp.

Before ordering a new coil try swapping it (and plug wires) with another cylinder. If the problem moves, then you probably need a new coil. But, before ordering a new coil see if just swapping the plug wire makes the difference.

 

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

Before ordering a new coil try swapping it (and plug wires) with another cylinder. If the problem moves, then you probably need a new coil. But, before ordering a new coil see if just swapping the plug wire makes the difference.

Good point /I am gonna go do that rite now.Thanks fOR EVERYONES HELP. Hope i am getting somewhere because the stripers are coming in..........

 

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

Tried it and wasnt as bad but still skipping.Clean all connections /switched it back and ran like crap again. Can this actually cause it to konk out all together/it didnt get areading at all when it was dying out.Hate to keep asking all these questions /I did notice my posts are building up but it still might be cheeper than going to the Mechanic.Thanks again John

 

[iwombat]

Re: 1988 Johnson 150/ran at home but not at ramp.

I don't understand the results. Did it follow the coil or not?

 

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

It did but did not seem as severe.Then when we switched it back it was more pronounced.Seemed to happen after it was warming up.Then she konks out.Gotta say i am not a mech. but am trying.Thanks to my neighbor who is somewhat.I guess i will try changing and hope for the best.

 

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

I think its time for the boat mechanic.Changed the coil and started it up and it ran a lot better but not 100% / Still had a small sputter so i figured i was getting close. I let it run at idle for 20 minutes without touching anything so i figured we had it licked / gave it some throttle for a bit no problem. Shut it down / went out an hour later started it up ran kinda crappie again but never shut down like the previous times.Gonna try running again this am.See what happens.It might be time for the guy with the rite equipment.

 

[kenmyfam]

Re: 1988 Johnson 150/ran at home but not at ramp.

I think its time for the boat mechanic.Changed the coil and started it up and it ran a lot better but not 100% / Still had a small sputter so i figured i was getting close. I let it run at idle for 20 minutes without touching anything so i figured we had it licked / gave it some throttle for a bit no problem. Shut it down / went out an hour later started it up ran kinda crappie again but never shut down like the previous times.Gonna try running again this am.See what happens.It might be time for the guy with the rite equipment.

Could be more than 1 coil ???

 

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

You could be right Ken. I was thinking of that myself.Because when i first checked my new plugs the bottom 2 were dirty but only got a bad reading on the 1 coil but from what i understand now is they act up after warming up??????????Maybe i will change 1 more before going to the mechanic. 25 more bucks..........

 

[kenmyfam]

Re: 1988 Johnson 150/ran at home but not at ramp.

You could be right Ken. I was thinking of that myself.Because when i first checked my new plugs the bottom 2 were dirty but only got a bad reading on the 1 coil but from what i understand now is they act up after warming up??????????Maybe i will change 1 more before going to the mechanic. 25 more bucks..........

Change all of them and have some spares !!!

 

[jonesg]

Re: 1988 Johnson 150/ran at home but not at ramp.

I agree with Kenny, you're doing it in increments when , due to age, it would be acceptable to renew all of them.

Did you ever have a headlight burn out on your car? change that one and the other one burns out 2 weeks later.! darn. Same thing for me.

I do however think with a bit more troublshooting you can zero in a bit more.
The proper tools will cost "break even" compared to paying a mechanic.
You can find out a lot with compression guages, spark gap tester, DVA meter and timing lights....and you can buy the lot for under $120.

Or pay de man.

 

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

Have not tried yet today but pulled all the plugs and noticed #1 and #6 had heavy build up on them so i went and talked to boat mech. and explained all my problems.#1 he said i did compression test wrong/should have disconnected linkage from carburators.90 across the board is to low for a 150 and may get a better reading the other way.If i only get 90 again he feels the motor is done??? He said they sell a spray for breaking down the carbon and to try this if i get a better reading.Could just be to much carbon breaking down and fouling out the plugs on #1 and #6?????????????

 

[kenmyfam]

Re: 1988 Johnson 150/ran at home but not at ramp.

Have not tried yet today but pulled all the plugs and noticed #1 and #6 had heavy build up on them so i went and talked to boat mech. and explained all my problems.#1 he said i did compression test wrong/should have disconnected linkage from carburators.90 across the board is to low for a 150 and may get a better reading the other way.If i only get 90 again he feels the motor is done??? He said they sell a spray for breaking down the carbon and to try this if i get a better reading.Could just be to much carbon breaking down and fouling out the plugs on #1 and #6?????????????

Fire the mechanic !!!!
90 across the board with one compression tester shows you everything is even. With another compression tester you may well get a different reading. Some of them are not that accurate. If you do have a bad carbon build up then yes a decarb is in order. Check the "Top Secret Files" for info on that.

 

[kenmyfam]

Re: 1988 Johnson 150/ran at home but not at ramp.

And do another compression check after decarb for comparison.

 

[Imissedem]

Re: 1988 Johnson 150/ran at home but not at ramp.

Thanks again Kenny/I will do that and get back to you in a couple days with the results.

 

[kenmyfam]

Re: 1988 Johnson 150/ran at home but not at ramp.

Good Luck and keep us all posted.