Johnson 110. 1989. Need help

boobie

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Re: Johnson 110. 1989. Need help

Do the basics. Check your compression and spark first. Spark should jump a 7/16 " open air gap on a spark tester. You can also do a cyl drop test on it when running by pulling one plug wire off at a time to see if you have a dead cyl.
 

emdsapmgr

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Re: Johnson 110. 1989. Need help

My guess is that the fuel pump you need for that high-perf V4 is 438559. This is a pump which will utilize the single pulse hose from the powerhead-same hose that the VRO used.
 
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boobie

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Re: Johnson 110. 1989. Need help

What happens if you pump the primer bulb when the prob occurs ??
 

fortyfreak9

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Re: Johnson 110. 1989. Need help

With the stock VRO system the engine would die if I didnt pump the bulb. So i converted to gas/oil mixed in the tank. The engine runs good at idle but in the lake it will not go over 2k WTO. Used the pump everyone said would work. Need ideas on what to do next. There is spark to all cylinders and no water or dead cylinder. It is a fuel issue.
 
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Re: Johnson 110. 1989. Need help

Might check your timing advance linkage. Follow it from the throttle cable up to the trigger arm make sure everything is moving correctly.
 

emdsapmgr

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Re: Johnson 110. 1989. Need help

You have the wrong fuel pump. One of the numbers on your Sierra fuel pump posting from yesterday is 385781. That part number was used on a 1974 Johnson 50 hp 2-cylinder engine.
 

fortyfreak9

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Re: Johnson 110. 1989. Need help

So it's not pumping enough fuel to the engine at WTO would be my guess? So what pump do I need?
 

fortyfreak9

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Re: Johnson 110. 1989. Need help

So if 385781 isn't right what one do I need? I was told be other people that have done the VRO conversion that 385781 was correct. Please help.
 

fortyfreak9

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Re: Johnson 110. 1989. Need help

I just disconnected the VRO wiring like everyone said, still have no idea what is going on, hope someone can help.
 

jere1972

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Re: Johnson 110. 1989. Need help

are you using a 3 line hose pump(in out suction) or 2 w/pulse hole on rear?
 

fortyfreak9

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Re: Johnson 110. 1989. Need help

2 hose with pulse in the back, mounted to block
 
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Re: Johnson 110. 1989. Need help

If you started with a vro2 pump, that is run from a pulse hose off the crankcase. You most likely need the older style 3 fitting pump used in the early 70s. Im not sure how you mounted a newer style pump to your block because the vacuum port to run the pump would be closed off and it wouldnt work at all? Also what did you do with the vacuum line from your vro to the crankcase?
 

fortyfreak9

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Re: Johnson 110. 1989. Need help

I was using the VRO2 until the gas side of the pump went TU. I changed everything to premixed in the tank and got the pump suggested. The pump mounts to the block wtih 2 bolts that screws the rear of the new pump where the pulse is. There was a fitting that I had to plug in order to use the new pump. Is the pump I have maybe not pumping enough fuel for the motor? I really don't want to get a new pump if I don't have to but I have to get it fixed.
 

johnson89

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Re: Johnson 110. 1989. Need help

thats the pump I put on a 1989 90 hp an it runs very good.....I have a complete install with pic's on this site it was about a year ago.....I was told by a boat shop that this pump will handel up to a 140 motor
 

fortyfreak9

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Re: Johnson 110. 1989. Need help

johnson89, do you have any more pics of how you ran all of your fuel hoses?

The motor also has a terrible time idling, if I move the shifter into gear it usually dies. I have to keep the throttle up even at idle.
 
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