1985 Evinrude 120hp V4 Fuel Issue? **UPDATED AGAIN**

[hilikus]

two-stroke engine...new gas, new oil...Just had the carbs rebuilt, lines flushed, new spark plugs, new water pump...took it out three weeks ago, ran like a champ...

took it out on saturday...went to prime the fuel line and the bulb would not get stiff...got up to speed and it started to "cough" and then died...smelled gas...thought it was flooded...waited 10 minutes, started it up and it started ok but then i couldn't get it up to full throttle...checked the bulb, it was firm...whenever i tried to get to full throttle it would die...i could run it at a low speed just fine...thought there might be air in the line, ran around the bay for about 30 minutes and still could not throttle up...put it on the trailer

my thinking is its a fuel starvation issue...the fuel line and bulb are original...i can fix simple things, im hoping to get a better idea of a possible diagnosis before i take it to a mechanic and drop a lot of cash...im wondering i may have a leak somewhere...i didnt have time to look for anything while i was there but will be going back this weekend...

any help is much appreciated

thanks

 

[HighTrim]

Re: 1985 Evinrude 120hp V4

Re: 1985 Evinrude 120hp V4

It is possible you may need to get yourself a new bulb. Dont cheap out with the aftermarket ones, pay for the OMC. It also sounds like it is flooded, not starved , the bowls are overfilling. Did you set up the carb after yourself? Were the high speed jets cleaned properly and thoroughally? Fuel pump filter clean? Diaphragm ok?

 

[_brad_]

Re: 1985 Evinrude 120hp V4

Re: 1985 Evinrude 120hp V4

What HighTrim said. Those aftermarket ones are junk.

 

[Solittle]

Re: 1985 Evinrude 120hp V4

Re: 1985 Evinrude 120hp V4

Other possibilities are the fuel pump or crud in the carbs. All easy to fix/work on.

 

[hilikus]

Re: 1985 Evinrude 120hp V4 Fuel Issue?

Re: 1985 Evinrude 120hp V4 Fuel Issue?

Spent about 6 hours replcing fuel and oil lines this past weekend...there were a couple of leaks and some cracked hoses...all of that is fixed...took it out and its still having the same problem so my thinking is carbs or fuel pump

now if its the fuel pump, i have a vro engine...does anyone know where i can pick up the special fuel pump and its not $350? also, im considering just mixing my gas and oil and putting in a regular fuel pump to support that change...any advice on this matter? links to parts, etc? again, this is contingent on it actually being the fuel pump...haven't had time to check the carbs yet

 

[iwombat]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

My bet is on the carbs. If you can get up to 1/2 throttle okay, the chances of it being the fuel pump are pretty slim.

 

[hilikus]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

thats my thinking...two of the carbs were rebuilt, so MY HOPE is that is the carbs...my buddy and i think it probably is, its just a matter of having the time to truely diagnose the issue...but im also getting myself mentally prepared that it is the fuel pump

a little update on what happened yesterday...started it up fine, reversed fine...put into forward, started it out slowly and it went ok...then tried to bring it up to speed and thats when it died...took the boat to his house and hooked up the water hose and let the engine run for about twenty minutes...it was running a little rough, almost like it was firing on only two of the cylinders which makes us think its a carb issue

 

[ezeke]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

edit

 

[Dhadley]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

First you said the carbs were rebuilt, then later you say only half of them got rebuilt. If you really only cleaned 2, go back and clean the other 2.

 

[HighTrim]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Paying special attention to those high speed jets, dont just soak them, clean them.

 

[hilikus]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

it was just one half of the carbs...thats where we are going to start

 

[hilikus]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Pulled the plugs today, they were wet. Pulled off the air-intake cover and noticed some burnt oil...also, the engine is backfiring a little...we've moved away from the fuel pump and are looking at the choke and intake valve...going to check compression tomorrow...any thoughts? we moving in the right direction?

 

[Dhadley]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

"Choke and intake valve"? A 1985 120 Evinrude doesn't have either. If the engine is backfiring, it may be out of time or have an air leak. Some oil in the airbox is normal.

 

[hilikus]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED**

and so it continues...checked the compression today, everything is a ok, which is actually a huge relief...back to the fuel pump and carbs

also, would something like this be happening if there were a power pack failure?

 

[HighTrim]

Re: 1985 Evinrude 120hp V4 Fuel Issue? **UPDATED AGAIN**

Start with rebuilding the carbs like stated. You cant properly diagnose problems without fully eliminating one problem at a time, and only cleaning half your carbs needs to be addressed first Id think. Pull out the jets and clean them thoroughally. FR or Tashasdaddy has a pic of the tool you will need. Let is all soak in a bath, then rebuild as per your manual. Faulty diodes in the power pack would cause a rough running engine, which is fairly easy to test.GL

Chris