1989 johnson 120 runs 2500rpm at full throttle

[Josh.R]

Re: 1989 johnson 120 runs 2500rpm at full throttle

i used to have a a boat with that same motor on it i had a same issue and it came out to be the jets in the carbs were not properly tuned....

 

[buggyman20]

Re: 1989 johnson 120 runs 2500rpm at full throttle

How can you tune the jets when they are fixed. They have no adjustment. Thanks all info helps.

 

[bktheking]

Re: 1989 johnson 120 runs 2500rpm at full throttle

How can you tune the jets when they are fixed. They have no adjustment. Thanks all info helps.

I believe you'd change the size of the jets, you'd physically change to a different jet.

 

[SparkieBoat]

Re: 1989 johnson 120 runs 2500rpm at full throttle

nice avatar BK,...LOL

 

[buggyman20]

Re: 1989 johnson 120 runs 2500rpm at full throttle

I have a few days off. I am checking the coils and other parts I can with ohmmeter. Do you think 40 degree temps would affect the readings?

 

[SparkieBoat]

Re: 1989 johnson 120 runs 2500rpm at full throttle

I check coils with a spark gap tester...under $10 at many auto parts store. It should get a blue streak across a 1/2 to 7/16" gap. 40 degrees should not affect anything.

 

[buggyman20]

Re: 1989 johnson 120 runs 2500rpm at full throttle

I checked the coils with ohm meter. All was in specs according to shop manual. I did have a couple of plug wires that had to be bent a certain way to complete circuit. What type of plug wires do I need?

 

[nymack66]

Re: 1989 johnson 120 runs 2500rpm at full throttle

Someone please correct me if I am wrong, I can't find anything that shows me this year 1989 V4 120 with a (CD4) has the SLOW feature installed.
I know for a fact my 87 140 v4 does NOT, plus no blocking diode..
Can someone verify if this operating temperature is acceptable for this motor? I thinking its 2 high but I no expert.

 

[ezeke]

Re: 1989 johnson 120 runs 2500rpm at full throttle

Someone please correct me if I am wrong, I can't find anything that shows me this year 1989 V4 120 with a (CD4) has the SLOW feature installed.
I know for a fact my 87 140 v4 does NOT, plus no blocking diode..
Can someone verify if this operating temperature is acceptable for this motor? I thinking its 2 high but I no expert.

Beginning with 1988 models, the big bore looper V4 120 and 140 have QuikStart and S.L.O.W incorporated in the newer powerpack part 0583489 now superseded to 584041. The last year for the older powerpack (0582262)on the V4 Looper was 1987.

 

[buggyman20]

Re: 1989 johnson 120 runs 2500rpm at full throttle

According to the " CE " LOOP SERVICE MANUAL for 120-300 HP. The motor has the S.L.O.W. warning system. It limits the motor to 2500 rpms when the temp reaches 203 degrees. The engine must cool to 162 degrees and be stopped to reset. By the way the CE is for the engine year in the model number. And it does have blocking diode in the wiring harness.

 

[nymack66]

Re: 1989 johnson 120 runs 2500rpm at full throttle

Thanks for the feedback Guy's, I was not sure now I know ...

 

[bktheking]

Re: 1989 johnson 120 runs 2500rpm at full throttle

nice avatar BK,...LOL

Not bad eh, although my nickname has zero to do with Burger King!!!

 

[buggyman20]

Re: 1989 johnson 120 runs 2500rpm at full throttle

I have checked the coils they check out ok. What would be your opinion if I get an orange or yellow spark instead of a blue spark? It is raining here so I can not check them today. Also would the power pack have a tendency to act up when it is hot and not when it is cold?

 

[buggyman20]

Re: 1989 johnson 120 runs 2500rpm at full throttle

Just checked the spark with tester. All 4 wires put out a blue spark on the tester. Measured at 1/2 inch. Any ideas?

 

[SparkieBoat]

Re: 1989 johnson 120 runs 2500rpm at full throttle

it could be an intermittent problem with one of the power packs..run it on the water until it starts to act up then test spark..

 

[ezeke]

Re: 1989 johnson 120 runs 2500rpm at full throttle

it could be an intermittent problem with one of the power packs..run it on the water until it starts to act up then test spark..

There is only one powerpack on this engine.

 

[SparkieBoat]

Re: 1989 johnson 120 runs 2500rpm at full throttle

roger that, could it still be a power pack issue??

 

[buggyman20]

Re: 1989 johnson 120 runs 2500rpm at full throttle

For anyone out there. Does anybody have any experience with the Power coil or Charge Coil or Sensor Coil going out and what it caused the motor to do. These are the only things I have not checked because I do not have the correct equipment to check them. Thanks

 

[buggyman20]

Re: 1989 johnson 120 runs 2500rpm at full throttle

Finally got it to the lake. I put new plugs in it. It gets out of the hole very well and runs good up to 3/4 throttle. About 4500 to 4800 rpms. When I opened it up full it started cutting out. When I backed off it smoothed out again. I tried this a couple of times and it did the same thing. Any ideas?

 

[jonesg]

Re: 1989 johnson 120 runs 2500rpm at full throttle

I just read all the posts from #1, I don't see that you have yet to discover whether you have a fuel problem or ignition failure.

Run it til it acts up.
A timing light will show if its dropping spark under load,
hitting the choke will show if its fuel delivery ( if the rpm's pick up).

In the meantime, you rebuilt the carbs?
did you do a link and sync ?