Mid 80s Johnson 40 hp

Outboard Related Only
mgsolakis
Posts: 161
Joined: Thu Apr 16, 2015 10:04 pm

Mid 80s Johnson 40 hp

Postby mgsolakis » Sat Jul 08, 2017 11:38 pm

Johnson 40 hp will not allow me to pump gas into it. The VRO is disconnected. It was working fine but started getting fritzy then stopped accepting gas altogether. I tried a new line and it still would not explain further. To explain a bit more, when I pump the primer bulb it gets hard but no gas goes through. When I pull the hose off it just sprays fuel. Any help would be appreciated.

outbdnut2
Posts: 360
Joined: Wed Apr 27, 2016 2:46 pm

Re: Mid 80s Johnson 40 hp

Postby outbdnut2 » Sat Jul 08, 2017 11:44 pm

Is your carb float stuck in the "up" position holding the float valve shut?

mgsolakis
Posts: 161
Joined: Thu Apr 16, 2015 10:04 pm

Re: Mid 80s Johnson 40 hp

Postby mgsolakis » Sun Jul 09, 2017 12:09 am

Could be but would the motor start with the float stuck? This one is starved for fuel.

david bartlett
Posts: 920
Joined: Tue Mar 10, 2015 10:15 pm
Location: Western Maine

Re: Mid 80s Johnson 40 hp

Postby david bartlett » Sun Jul 09, 2017 12:25 am

mgsolakis wrote:Could be but would the motor start with the float stuck? This one is starved for fuel.


It would start if the bowl had fuel in it. If the float pin is stuck closed, after the initial fuel in the bowl is used, it would not run.
AOMCI Member
Member Pine Tree Boating Club chapter of AOMCI

"I don't fully understand everything I know."
"There is nothing — absolutely nothing — half so much worth doing as simply messing about in boats." (Kenneth Grahame)

mgsolakis
Posts: 161
Joined: Thu Apr 16, 2015 10:04 pm

Re: Mid 80s Johnson 40 hp

Postby mgsolakis » Sun Jul 09, 2017 10:08 am

Okay so guesses see to involve an inspection of the carb as a first step. Thanks, I'll take a look. I was not sure if the fuel fitting on the motor or the fuel pump could cause this.

User avatar
Garry in Tampa
Posts: 1864
Joined: Mon Mar 09, 2015 2:32 pm
Location: Florida

Re: Mid 80s Johnson 40 hp

Postby Garry in Tampa » Sun Jul 09, 2017 10:44 am

Pull the fuel line off he carburetor and see if the primmer bulb in the line then works. If not, the fuel pump may be improperly assembled, or have a clogged filter. . . :)
Image

fleetwin
Posts: 1790
Joined: Mon Mar 09, 2015 4:27 pm
Location: Rhode Island

Re: Mid 80s Johnson 40 hp

Postby fleetwin » Sun Jul 09, 2017 3:11 pm

I "think" I understand what you are describing, but want to make sure....Primer bulb won't pump up, seems hard already, fuel sprays from fuel connector when line is disconnected.
I am assssuming the engine ran before, but does not run now, and no work has been done...
I like Garry's advice. If fuel does pump from the carb supply line, then reconnect the hose, pull the carb drain plugs and try pumping the bulb again...
If no fuel pumps from the carb inlet line, I would check the engine side of the fuel connector. Some of these engines had a check valve on the connector that may be messed up. You mention that the VRO has been disabled. Is the VRO still in place, or has it been replaced with a fuel pump?
Perhaps the VRO is messed up or improperly plumbed, maybe someone swapped the fuel inlet line and pulse line....
Or, like Garry says, perhaps the fuel pump filter is messed up...

mgsolakis
Posts: 161
Joined: Thu Apr 16, 2015 10:04 pm

Re: Mid 80s Johnson 40 hp

Postby mgsolakis » Mon Jul 10, 2017 5:40 pm

This is my brother in laws Motor and he claims it was fine then stopped working. I will try Garry's advice, and Fleetwin I will check the fuel pump as well. I do believe that the VRO is gone and replaced with a fuel pump if my memory serves. I'll be up there this weekend. Thanks for the suggestions and I'll let you know what my findings are.

mgsolakis
Posts: 161
Joined: Thu Apr 16, 2015 10:04 pm

Re: Mid 80s Johnson 40 hp

Postby mgsolakis » Sat Jul 15, 2017 9:44 pm

So I pulled some of the hoses off, and go pumped through the motor fitting, through the fuel pump and into the carb. I put it all back together and pumped fuel into the engine and it filled normally. The engine started right up. Why?

Jerry Ahrens
Posts: 698
Joined: Tue Mar 10, 2015 9:49 pm
Location: Lake of the Ozarks Mo.

Re: Mid 80s Johnson 40 hp

Postby Jerry Ahrens » Sun Jul 16, 2017 8:43 am

It sounds to me like you had an air pocket inside the primer bulb. The correct way to use a primer bulb is to hold in horizontally, with the OUTLET side of the primer bulb facing upward. While squeezing the bulb, the internal check valves will work alot better. This may sound crazy to some, but it works. Some boats that I've worked on have the fuel line routed in a way that makes it difficult to hold the primer bulb in this manner, or the line may not have enough slack in it to allow this.
The cheapy aftermarket primer bulbs are notorious for this kind of thing as well. By a Quicksilver or BRP (OMC) primer bulb to get a good one.
Jerry Ahrens AOMCI Member MAPS Chapter President


Return to “Ask A Member”

Who is online

Users browsing this forum: Garry in Tampa and 10 guests