Johnson 2.5 HP 2006 J2R4SDS

[Travis79]

All about the model above

 

[Travis79]

I've started this topic to ask you guys for a help.
I have this engine for some time running fine and few days later it got broken.
Currently it wont start.
It has happened that I've let it stop on the water in gear with gas set to minimum few times. The boat was slowing down and when it almost stopped, the engine stopped (I know, not perfect :facepalm: ...damn fishing)
After the last shut off, this way I had to pull few times (even the engine was warm) and the engine exhaust banged like choked and stopped. New few attempts to start the engine I had to set the gas to 3/4 of the range without the choke, it turned few times and stopped. Now, it wont start at all.

I've checked the spark - OK
I've checked the fuel hose - OK
I've dissembled the carburettor and it looks "clean"
I've tried to inject fuel into air intake before the start without any better result.
The valve seems to have the compression as when attempting to start without the spark, there is sound of air compression.
I've looked at the coil, wondering if timing could be wrong and it seems that this model has quite fail-proof coil system. Magnet and coil is fixed.

Any idea what the "incorrect" shut off of the engine could cause?
Would you be so kind and give me some hints what and how to check to troubleshoot this engine, please?
To reach the service is quite difficult because of distance and its availability.

Thanks in advance.
Travis

 

[Crosbyman]

could be just bad gas…., nay filters to check ?? bad plug or crudded plug

carb looks clean isn't enough …. all passages must be clear of junk… varnish who knows what

 

[Travis79]

Gas is new, no old left in the tank.
Plug is creating the spark
If the engine was running fine before the situation I've mentioned (shut off in gear by resistance), could it be the carb issue still?

 

[Crosbyman]

you have good gas…. sparks compression but gas must reach cylinders so….check fuel flow all along it's path

tank (filter if any ??)
feed hose blocked or gone bad due to ethanol...some hose plastic liners fall apart inside check fuel flow out the hose at the carb inlet ….
crab inlet needle stuck
float stuck shut
fuel passages inside the carb need cleaning again use carb cleaner AND AIR PRESSURE ( use a Dollar store keyboard air cleaning can if you have no compressor ….blow all passages


& btw I doubt "

shut off in gear by resistance" cause any issues just mho

check/disconnect kill button

keep at it patience brings joy ​

 

[raczekp1]

there in fuel tap is fuel filter. its puhed into fuel tank outlet.
just extract this fuel filter and clean it.
check water circulation and if water pump is working fine.
water pump is just behind propeller. in gear box cover

 

[Tim Frank]

Check for sheared flywheel key, and then check compression.

 

[Vic.S]

I believe this engine is a re-badged Suzuki ?

Whether of not that right There has been a topic running on one of the UK YBW. Com forums about similar problems with a Suzuki DF2.5.
It turns out that with less than 10 hours use one of the push rods had jumped out and disappeared into the oil pan.

Worth investigating ?

I dont know if the link will work

http://www.ybw.com/forums/showthread.php?508694-My-Introduction

 

[Travis79]

OK, so this mystery is solved for me now.
The cause this time was the spark plug which was malfunctioning.
It was creating spark, but irregularly. The visual check of spark outside the chamber cannot disclose it as you see some sparks happening.
Replacing the spark with a new one solved this issue.
Thanks guys for your hints.