115 evinrude dies when engaged in gear

[frextrev]

1977 115 E. Starts easy. After it gets warmed up it will choke down and die when put in gear. Rebuilt carbs. Mechanic said head gasket bad. $350 dollars later, it still does same thing. Mech says compression low on #4 and fuel pump not working properly due to low compression. Any suggestions. Is it possibleto insert electric fuil pump in gas line?

[phillnjack]

sounds like mechanic is a rip off merchant.
why didn't he do a compression test before any work at all was carried out on the engine ?
compression test is the very first thing to do when trying to fix an outboard engine.

The fuel pump could need a service, these service kits to rebuild the fuel pump are very cheap and very very easy to do.

The dying down sounds like carbs need a clean out and lync and synce with the timing to get it pulling a bit of power in idle.

do you know what the compression figures are for each cylinder ? this again is very easy to do and a compression tester is mega cheap tool that youl have forever (unless you drop it and run over it ).
you simply take out the plugs and put in the adapter and turn the engine over with the safety cord off so the engine don't start, this will show in just 4 seconds what the compression is for that cylinder, then do the other 3 etc.

fuel pumps do lose the strength in the diaphragm, this is a usual thing to replace about every 5 years or so, and more if used daily (every 2 years).
some have had the originals on for 20 years and then wonder why its gone bad ha ha

Now if you start the engine and get it warm, just before it dies try squeezing the fuel bulb from the fuel line and see if this makes a difference !!!!! if it does then it could well be the pump, but could also still show that the carbs need cleaning out with some proper carb cleaning fluid.

hope this helps


phill

[C6inFL]

Originally posted by frextrev View Post

1977 115 E. Starts easy. After it gets warmed up it will choke down and die when put in gear. Rebuilt carbs. Mechanic said head gasket bad. $350 dollars later, it still does same thing. Mech says compression low on #4 and fuel pump not working properly due to low compression. Any suggestions. Is it possibleto insert electric fuil pump in gas line?

How low is low? did he tell you the readings for each? Have you checked the compression yourself?

You can check the fuel pressure. Don't know what model # engine but if you have a vacuum tank, check between there and fuel rail (use clear tubing) .

Also try a vacuum gauge between the on engine fuel filter and the VRO pump. Use clear tube to see if air bubbles.. If more than 4hg of vacuum or air bubbles you have an air leak in the fuel lines. If you do, use an external tank, like a "gas can" and try to isolate if the leak is at the motor or the tank side.

Did you rebuild the carbs? Did you do a link/Sync with the throttle cable disconnected? Also, what about the slow speed mixture settings? Were they adjusted / reset after the rebuild?

[joeanderson]

I have a 90 model 115 doing the same thing. I think a fuel problems. Bottom cards not getting fuel. Can the fuel pump be changed with a plan fuel pump and oil injection just bypased with premix fuel??? I just found this out but its only running on 2 of 4 cylinders. #1and2 running and 3and4 nothing can pull plug wires and no change in motor speed. Plugs are fireing and yes cards have been cleaned. Any ideas????

[C6inFL]

Originally posted by joeanderson View Post

I have a 90 model 115 doing the same thing. I think a fuel problems. Bottom cards not getting fuel. Can the fuel pump be changed with a plan fuel pump and oil injection just bypased with premix fuel??? I just found this out but its only running on 2 of 4 cylinders. #1and2 running and 3and4 nothing can pull plug wires and no change in motor speed. Plugs are fireing and yes cards have been cleaned. Any ideas????

How do you know there is no fuel getting to those cylinders? The VRO pre-mixes the fuel/oil and that is what's pumped to the carbs. No fuel would = no oil.. If you can pull the bottom two cylinders plug wires it sounds more like maybe bottom coil? Did you do a spark test? Should get a 7/16" spark gap tester, can get at any auto parts store.

[joeanderson]

Yea good spark on both cylinders fixed fuel problem now it was the float needle valve was pluged was getting fuel but not enough. The flow was restricted by a piece of rubber. Boat runs fine now in water and out does about 60 mph or close to it. But I still would like to byp*** the vro oil injection what mixture should I run? And how to byp*** it any ideas???

[joeanderson]

And BTW thank you for the info before and after. I am new to out board motor past boats have been inboards which are very easy for me to work on but now this inboard is testing me lol. But I think I have them figured out and I just read that the mixture is 50:1 since the 70s model on all HP motors is that true

[C6inFL]

Originally posted by joeanderson View Post

And BTW thank you for the info before and after. I am new to out board motor past boats have been inboards which are very easy for me to work on but now this inboard is testing me lol. But I think I have them figured out and I just read that the mixture is 50:1 since the 70s model on all HP motors is that true

Glad to hear it's running. You can plug the VRO Oil side and still use the fuel side and just premix.. I would get the shop manual so you know how to disconnect the VRO alarm.

From what I've heard when Oil side of the VRO fails it typically pumps too much oil, not less. If you get the manual it will show you how to do a oil volume test on the VRO and how to test the low oil alarm and how to verify if it's priming.