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Puzzling Engine

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crownroyal

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" My 1988 Johnson 60 hp has be

" My 1988 Johnson 60 hp has been rebuilt. Compression in all 3 cylinders are 140. All 3 carbs have been rebuilt twice,never found any trash or gunk in jets or bodies.Lync and sync is right and the timing is set right.Pump bulb stays hard and there is no gas leaks or air leaks.No trash in gas tank and have fresh gas with oil mixture(vro pump disconnected couple yrs ago). The problem thats driving me crazy is the engine will start and idle just fine. You can rev it up with the warm up lever and it revs as high as you want to go.When you put it in gear is when the problem starts. It bogs like its out of gas ,push the key swith in a couple times and it runs like a new motor. It will run wide open throttle all day long with no misses or bogging down. Seems when youre running wide open throttle and put it in neutral ,wait a few seconds and give it WOT it takes off just fine. But,when you stop and fish for a while with engine off and start back up,itll start fine but when put into gear it bogs. The bulb is hard but it still seems like a fuel starvation problem. Any suggestions would be helpful. All i can think of is the fuel pump(but id think it would miss or not get full rpms if it was fuel pump or it could be the valve the 3rd like from fuel pump goes to(maybe its bad) . Got me puzzled "
 
"Assuming that you are correct

"Assuming that you are correct and that the carburetors are in perfect condition, first check to see that the timer base under the flywheel isn't sticking which would keep the timing in a retarded position.

The fact that pushing the key in, activating the primer solenoid, results in the engine running properly indicates that (if the carbs are okay) the throttle butterflies are opening too soon. They should just start to open when the scribe on the cam aligns dead center with the carburetor throttle roller.

Joe
"
 
" Hi Joe,ive tried different s

" Hi Joe,ive tried different settings on the cam roller(letting it open earlier and sooner),and the timer base is working correctly.Ive heard these type carbs are a pain to clean with the brass or copper tubes running thru them. Ive noticed that the smaller tubes inside the larger tubes lean up against the larger tubes in the carb on the bottom in the bowls. IS this normal or is the tubes shot? No cracks in the tubes though. Would you rule out the fuel pump and also i can blow air thru the fuel hose that connects to the engine when i take it off from the fuel pump. Anyway to test to see if that valve is working properly or is it just a conection? Thanks "
 
The small tube is off to one

The small tube is off to one side that is normal.Any engine will rev in nuetral it means nothing.Does the motor have an adjustment on the low speed jets???Does the motor have the black plastic covers on top of the carburetors????
 
" Hi Sparky no theres no adjus

" Hi Sparky no theres no adjustment on the jets and theres no black cover on top of the carbs. The jets and tubes are spotless,thats whats got me puzzled "
 
" Hi...
Are the last 4 letter

" Hi...
Are the last 4 letters in your model No.LCEA..?
If so, I have the parts manual for that motor and maybe I can help you with your problem....TommyG "
 
I have a 2001 Johnson 90 Mod.

I have a 2001 Johnson 90 Mod.J90PLSIF and your problem sounds almost exactly like mine. I can get it to run with the key pressed in and as soon as I put in gear it sputs then quits. All symptoms identical except hard to idle in neutral. Did you solve the mystery? This one has me extremely perplexed and that doesn't happen often to me on two cycles. Tried Everything and about to pull my hair out. Any help would be greatly appreciated. Ph. 817-797-9876 or 817-358-0812 Mike.
 
" I agree with ya Mike. It see

" I agree with ya Mike. It seems like a carb problem but ive cleaned them 3 times with new kits and all. If it was a jet clogged looks like it would act up a full throttle also but it doesnt. The timing base is correct and its not sticking ,all i can figure is the fuel pump is not pumping enough pressure at low rpm's. It doesnt cut out at all at full throttle and after it kicks in you can go below full throttle and it does fine. Just seems it needs that little kick of fuel when you 1st take off and then its ok. Mike ,,,if you find out what fises yours let me know and anybody else got any suggestions id appreciate them. "
 
" This is just a thought,but t

" This is just a thought,but try the throttle shaft bushings where the throttle shaft goes thru the carb body, if there is wear it will not open and close right. It could be binding on inital engagement and not opening the flaps both sides at the same time. You know opening cockeyed "
 
" HI
I HAVE A 3 CYL EVINRUDE

" HI
I HAVE A 3 CYL EVINRUDE 70 HP ?91 MODEL.
SAME PROBLEM. HAD IT TESTED 3 TIMES AND SErVICED. STARTS EASY, RUNS WELL FOR 5 MINS THEN REVS DOWN TO 2000 AND STAYS THERE.IF OPEN THROTTLE IT JUST SPLUTTERS.IF I PRESS IN STARTER SWITCH FOR SECOND IT PICKS UP REVS IMMEDIATELY and goes well for a few seconds untill I press it again. COMPRESSION TEST ETC WAS OK, NO OVERHEATING.
DESPERATE "
 
" Try opening up the air relei

" Try opening up the air releif valve on the gas tank. Im serious. High Rpm overcomes the vacuum in the tank, a low RPM or Load will prevent proper feed. "
 
"The bowls on these carbs have

"The bowls on these carbs have well in the center where the high speed fuel pick up is. The high speed jet that feeds these wells ,is in line with the bowl drian plug. I have found these get build up and creat the problem you describe.Using a copper strand of wire careful not to scratch the jet cleans them."
 
"When all else fails check the

"When all else fails check the source... The vent to your gas tank has to be open and sometimes the pump bulb on your fuel line will not function properly and allow fuel to move as it should. choking the engine will sometimes cause the bulb valve to open, but changing the bulb might repair the problem..Thanks...JIM"
 
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