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Rebuilt Motor Blowing gas out carbs

K

kjdavi76

Member
1995 Evinrude 200 Vindicator E200STLEOA

Rebuilt the engine and now it wont idle or run right.
The carbs are blowing fuel out instead of sucking it in. Would installing the pistons with the exhaust side of pistons aligned with the intake side. Motor turns nice and free and has good compression but I cant figure out why the carbs are blowing gas outwards. I can feel the carbs sucking and then blowing on each stroke of the piston. Have checked the VRO pump out and the carbs have been rebuilt. Can pump up the bulb firm and no gas leaks anywhere. If anyone can possibly verify my problem I would greatly appreciate it.
 
Very curious. I don't know about orientation of the pistons, but I can't imagine that would cause this issue. As far as I know the pistons on that engine are uniformly domed so it's not like it would squish the air in any particular direction.

If it were me I would first pull the carbs and make sure all the reeds are in good shape. Make sure no gaskets are missing, petals are good, etc. It's pretty odd that all 6 are doing it, but this is the easy thing to check.

Were all 6 cylinders re-sleeved? Maybe the machine shop got the sleeve oriented wrong and the exhaust ports aren't lined up?

The only other thing is you might have an obstruction in the exhaust. Whoever re-installed the powerhead could have left a rag or something like that in the mid-section and it's blocking exhaust flow causing excessive backpressure in the cylinders. Another option, did they tape over the mid-section mating surface to paint the bock and possibly forgot to remove that during installation? Or, even crazier, while the engine sat with the powerhead off did a little critter make themselves at home in the midsection?

I know these are wild ideas and I'm completely spit-balling here. But, if the reeds are in good shape then some sort of blockage in the exhaust a possible explanation.

KJ
 
It will start and idle on swapped pistons...just no power. Check flywheel key to see if sheared? Cylinders wired correctly?
 
Go back and read the service manual. If your rods had dots did it indicate to
orient the dots towards the flywheel or away? I just rebuilt a 1990
60 hp and on one page it states it does not matter but then a couple
of pages later it states TOWARDS THE FLYWHEEL.
Just asking.
Oh yea, mine would not start either and I found out I had a faulty
power pack.
 
Hey everyone wanted to update this post. I ordered new reeds from Boyeson and problem is solved. Had to resurface the reed cages and change idle air jets but other than that just put the new reeds on and problem solved.
 
Thanks for following up with your resolution. The OEM Reeds will just about last forever, but Boyesen's are a fine option too. Sounds like your reeds got bent or banged around when they were out of the motor and were not sealing properly against the cages. Reeds are your only valve to keep the crankcase pressurized with air/fuel charge and any leaks around them will cause running issues.
 
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