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04 90 JOHNSON IS SICK

I

in2deep

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MY 90 DOES NOT WANT TO IDLE OR

MY 90 DOES NOT WANT TO IDLE OR TROLL IN THE WATER BUT WILL PLANE OUT FINE AND RUNS GOOD IN THE YARD IVE HAD CARBS REBUILT A NEW OPTICAL EYE CHANGED PRIMER BULBS NO WATER IN TANK AJUSTED CARBS STILL NOTHING SOMETIMES STARTS FINE AT THE RAMP GET TO MY FISHING SPOT FEW HOURS LATER YOU CANT START IT THE SHOP CANT FIX IT EVERY THING CHECKS AOK ANY INFO OTHER THAN MY SPELLING THANKS TROY
 
thanks for the info.i also for

thanks for the info.i also forgot to ad that since i got it back from the shop it has alot of oil on the prop and i checked the plugs they are very oily im wondering if its to lien thanks
 
"Well, I can only pull from my

"Well, I can only pull from my two experiences w/ my boat, but both had the same symptoms.

My '98 90hp use to idle rough, stall a lot, smoke a ton, and sounded like it had a cam when idling. It ran great on plane though. Turned out a head gasket (o-ring on my particular motor) had failed resulting in water in the cylinder, washing out oil, etc. The excess "smoke" was also partially steam. I knew something was up b/c that cylinder had low compression - I ended up having the motor rebuilt. So, have you done a compression check?

Then last week it wouldn't idle at all - smoked a ton, but ran fine on plane. I did notice it hiccup a few times on plane, but that was it. It turned out to be a bad fuel pump.

If you are still using the oil injection system (and I have no idea if yours is anything like mine or not), but is it possible it could be injecting too much oil?!? At full throttle it would burn it, but at idle, it doesn't need as much, so if yours is malfunctioning, that would cause smoke, rough idle, etc.

Just some things to look into if you haven't already. Otherwise I'm of no help"
 
"That helps, thanks for the in

"That helps, thanks for the info. I just unhooked my oil tank today, and started mixing it 50:1. runs a ton better. I pulloed the plugs, and it's real wet, don't know if its to rich or lean. Did you have to readjust the carb when you unhooked your oil tank?"
 
"I personally didn't disco

"I personally didn't disconnect my oil system - the mechanic that rebuilt the motor did. I do not recall him saying that he made any specific carb adjustments for it (I was sure to stay informed on the build-up, parts, etc along the way). Hopefully someone else can chime in or you can start a new thread regarding pre-mixing and try to get some help. (or search - gotta be threads on here for that)"
 
"to disconnect oil injection p

"to disconnect oil injection pump just plug it off and cut the grey wire,and dont forget to mix
previously you stated it was smoking a lot,are you sure its not steam mixed with the fumes,oil burns blue water is white ,steam.
also when was the last time you checked compression."
 
"ive already disconnected the

"ive already disconnected the oil pump,and ran the boat runs much better.andrews post about to much oil at idle made since.but i have not checked compression ive loaned my tester out and triying to hunt it down now.but i was just wondering after disconnected oil injection and mixing fuel & oil should there be any carb ajustments. it really doesnt smoke at all. thanks for the help"
 
"no adjustments are needed,i d

"no adjustments are needed,i did the same to mine
runs great since rebuild just 50:1"
 
"need some help. my engine ran

"need some help. my engine ran good for awhile after i disconnected oil inj. but now it started doing same thing.it smokes alot and it didnt before. idles like it has a cam in it. stalls alot. but still run fine on plane with no problems.i put it in a drum of water today and noticed there was alot of oil on the eng an the tank. also checked the compression. they range from 110 to 125 on 4 cyl,s ran sea foam thru tank of gas that was mixed 50:1 didnt seem to do any thing.also when running rough in the water i pushed the choke in and it killed the engine.any help greatly apperciated"
 
i just looked at my roller tim

i just looked at my roller timing ajustment and it was incorrect. i have just made ajustments.at 10:00 pm tonight thats how much its bugging me. i will try it out in the morning. thank you for your help
 
check the cylinder reading 110

check the cylinder reading 110..the spread between highest and lowest compression is more than desired
 
the readings were at full bate

the readings were at full batery. saftey pulled all plugs out. spun the eng till the gauge stoped going up. readings. 120-125-110-120. then turend over 5 revolutions per cyl and got 100-115-90-100.
 
"Well, your new conditions sou

"Well, your new conditions sound EXACTLY like mine before the rebuild. My cylinders were 108, 125, 125, 125 - just slightly out of the 10% rule, but I got the boat for a good deal, so I went w/ it. I ran sea foam & deep creep through the motor also and didn't have any luck. After running the motor a few times, the low cylinder had dropped to 90 - that's when i took it to a mechanic and like I mentioned earlier, discovered the problems and $3000 solution. Hopefully you don't need a rebuild, but honestly, it sounds like you're heading in that direction"
 
"yea dont sound good for me. s

"yea dont sound good for me. sounds like i need to get the KY ready. i guess ill have to take it in.
but on a good note iran the boat sunday and it didnt do bad after making ajustments to the roller, timing bearing. thanks to mr.JWB marine help with that page.but it did stumble a few times at idle. so i guess will see what happens. but thank you guy,s for your help. <font color=""ffff00"">THE SUN IS HIGH AND BRITE IN NORTH EAST </font>FLORIDA
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"
 
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