Johnson J90TLCIM hardf to start after it has been running for awhile

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Hi there, on initial cold start, I can use the fast idle no problem and within 30 seconds put in gear and the motors goes no issues. Once it is shut off and sits for 10 or more minutes, it is very hard to start, turns ok but wont keep running and if put in gear stalls. if I try to use the fast idle also it will just stall. I have to let it sit idling for possible 5 minutes then i can use the fast idle or put in gear and runs fine after that, any thoughts??
 

racerone

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After warmup do this test.-------Leave all plugs in.--------Use a spark tester set at 7/16"gap and see if you have strong spark,
 

emdsapmgr

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After shutting down a running engine, the powerhead will heat up significantly. This heat can affect weak ignition components. Once running again, the impeller will cool the powerhead down to normal operating temps. Agree-check for spark when the engine is heat-soaked.
 
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I am kinda thinking the heat would have something to do with it. what components should I replace? I am pretty sure it is a ignition component that i should just change and try
 

racerone

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Where in Canada ?----I am pretty sure that you need to do some testing first !-----Could be as simple as the starter motor needing repairs.---Throwing parts at it gets expensive in a heartbeat !!
 

racerone

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????-------Everybody says that their starter works fine.--------That is untill they fit a known to be good starter !-------Testing / inspection is the path forward.
 
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what are you talking about racerone??? I know 100% the starter is fine and that is not what i am having an issues with .If you read the 1st post you will see the issue. a bad starter and not going to made a motor stall, or do you really think that???
 

1983 ercoa 21'

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Cranking rpms should be 250.
as to what to test.
power pack
stator
timer base
coils
plug wires.
refer back to your first response and start by warming up the motor then doing a spark gap test making sure it jumps a 7/16 gap.
cdi electronics will have step by step procedures for testing your other ignition components.
remember to test when warm or you won't find your problem.
 
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Cranking rpms should be 250.
as to what to test.
power pack
stator
timer base
coils
plug wires.
refer back to your first response and start by warming up the motor then doing a spark gap test making sure it jumps a 7/16 gap.
cdi electronics will have step by step procedures for testing your other ignition components.
remember to test when warm or you won't find your problem.

Do you have link to this site? a couple other people around town say possible the power packs also. I see a few of them on ebay for around $65 so not sure if just buy a couple of them and try it? the motor seems to of had one replaced already as one is black and the other is blue.
 

emdsapmgr

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1983 posted the website for great electronic component troubleshooting: cdielectronics.com They have the best info for testing the voltage outputs from the stator and timer base. You will need a special "peak reading" voltmeter to accomplish these tests. So, if the timer base and stator check ok, you are really down to the power packs. Further, once you know it's an electronic ignition component, you can do your own shade tree testing. You can swap the 4 coils, and both of the power packs. Seeing what happens with the spark when components are swapped will tell you a lot.
 
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image_229609.jpg Thanks Guys, going to get a couple of power packs and replace those and see how it is.

I did take it out again toady and started to and when i slowed down after about 10-15 minutes started to run rough. was having a hard time keeping it running and took the cover off, and found this, a broken plug with. it looked like it has been broken for some time as there was ox idization on the cable. I tried to repair it the best I could in the boat and got it running again and running pretty good to for about 1 1/2 hours. When I went to load up, I shut it off an went and got trunk and was getting it ready to load, and started it up and seems to run pretty good and was able to use the fast idle right away without it quitting, is it possible that it is just a plug wire that was causing the issue? or should I still replace the power packs? thanks for everyone help with this issue.
 

emdsapmgr

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Replace a pack when it is found to be defective through testing. No need to replace one that still functions.
 
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Replace a pack when it is found to be defective through testing. No need to replace one that still functions.

The problem with that is it cost more for the test equipment to test properly and in a shop here they charge a minimum of $75 plus tax to asses the module, it is only 64 to replace one. So I can just swap out and seeing they having been change in some time, spending a few bucks on a motor I am planning on keep isn't that bad. Even talking to a few places around here, they say it would be hit and miss on finding issues, as they want to keep for a few days to run and heat up and a few hours in the shop is more that what the parts are worth. Just would be nice to hook something up or to find a person with the same issue so limit the number of parts
 

racerone

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You can do a lot of the testing with a multimeter, about 40 loonies at Canadian Tire.------------Or you can throw parts at it and even a " blind squirel can find the odd acorn " is a saying that comes to mind.
 
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You can do a lot of the testing with a multimeter, about 40 loonies at Canadian Tire.------------Or you can throw parts at it and even a " blind squirel can find the odd acorn " is a saying that comes to mind.

if you look up the testing to do it properly, you need more then a multimeter and i would rather throw money to a part like the power pack than a starter motor.
 

racerone

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I have repaired these motors for many , many years.---The starters on these motors are elegantly easy to inspect and repair.---That is if you want to learn how easy it is.--------Understanding the basics makes the testing easy, very easy !!!!!
 
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