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1989 johnson 40 hp vro bogs down at wfo

L

lloyd keast

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"this engine runs great at low

"this engine runs great at low idle. At wfo it cuts out then comes right back on. I feel it is a fuel issue because i can hold the choke when it cuts out and it recovers. The cut out doesn't instantly cut, its more like it boggs down. I have checked for water,changed the plugs, changed fuel lines and filter, and replaced the bulb. both plugs are whitish grey. I ran carb cleaner through the last tank, and it made the problem worse. now it cuts/bogs at all throttle ranges. This outboard I have just puchased, and it has been in storage for two years. Does any one think that a simple acid bath carb cleaning and kit would solve the problem. Or is this something that is typical with the 40 hp vro? Also the VRO is disconnected I didn't want to mess withy it. I'm more comfortable mixing gas."
 
"You should check compression

"You should check compression wonder why the vro is unhooked could of had a oilissue and seized the 40,s were good for scored walls when vro quits may need an overhaul pull the head and look inside will get rid of the guess work if ok a head gasket is pretty cheap to get peace of mind as to the real shape of your motor but it may only be a spark problem good luck"
 
"LLoyd,

I'm playing wit

"LLoyd,

I'm playing with my 96 48 hp spl becuase it is having similar problems and I have heard of others having problems similar to yours. If the engine is new to you and has been sitting around for a couple of years then a good carb job would be in order. two aftermarket kits will run you just under $40 total. You can probably do the job your self as these carbs are very easy to take apart and reassemble.

The carbs are the first place to start. As waterman suggested you should check your compression. this is for diagnostic purposes as well as for your information and future reference. Lots of people don't trust the VRO but it is very reliable. mixing is great too though and should not play a role in your symptoms.

Give us more information regarding rps's when problems occurs, engine temp: hot or cold, etc BUT REBUILD THOSE CARBS!


Check out this other posting regarding similar symptoms
http://www.marineengine.com/discus/messages/12478/150796.shtml"
 
"The problem occurs at all tem

"The problem occurs at all temps. Right after startup through hot. The rpms @ wfo are 4200. The problem bounces the rpms from 4200 down to 3400 and back again until it quits or I back off the throttle, or hit the choke. I am in the process of the carb kit as we speak, I'll let you all know as soon as I get it done and test it.Thank you guys for your help!"
 
"Problem solved. I just wanted

"Problem solved. I just wanted to thank A Waterman and 14 ft sea nymph for your help!!! The problem was two fold. The carbs did need to be cleaned, but that in itself didn't fix the problem. After put back togeather the problem persisted. The electrical system was checked next. At WFO I wasn't getting spark to one cylinder. at low speed it was intermittent.All components were checked per the clymer manuel, and by an experienced mechanic. They tesed fine. So there for he checked the connections. Guess What??? Corrosion. All wires were disconnected and cleaned. Both cylinders fire great and runs smooth at low end. Oh and by the way, I know that people think it's redundant to check the compression, but it needs to be done!!! Mine was good but lack of it could cause the exact same symptoms. Again thanks to the folks who helped

Lloyd"
 
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