'84 35HP Evinrude Troubles (STILL!)

Palssonater

Seaman
Joined
Jul 3, 2007
Messages
60
A while back I posted about my primer valve being faulty and the fuel pump flooding the motor out via the primer. I've since removed the primer and tuned the motor accordingly. Nice tan colored plugs now when running. I've never used the primer in warm weather to start and it would start on the 3rd pull every time last year.

The problem still exists in starting the motor and keeping it running. I've taken the carb apart and checked needle and seat, main jet and fuel mixture needle. Everything checks out there. The only thing I haven't done is to see if the float will actually float in a bowl of water(just thought of that now as I type).

It took me about 20 pulls to get any sort of feeling that the motor had helped itself turn over by combustion. Another 20 to get it coughing and sputtering. By removing the fuel line from the motor and pulling it seemed to help the motor start and idle for a time. I then replaced the fuel line and primed the ball to fill the carb. It would idle for a bit more and then die out. Had to remove the fuel line again to get it started. I went through this process about 5 times before I took it for a ride.

Now the motor running fairly soundly at first begins to die as I throttle up. I slow and prime the ball again. And repeat this procedure a couple of times. Eventually the motor is running fine and I pick up some passengers and we go on our way fishing. About a mile down the river after running at WOT for that time it sputters out and the ball again is softer than normal running. Slow to a idle, pump primer and continue the next mile unphased.

Used it the entire day fishing, starting the motor with one pull here and there to move us around our favorite spot and fill our stringer. Off we go back up river to the launch. Flawless almost the whole way, but then dies right on the last leg of our journey. Boat comes to a stop and I put it neutral to start it on the first pull and keep on the go. Finished by loading up.

So this is starting to get to me. I have the fuel pump repair kit on order, however by inspection of the diaphragm it looks fine. All the gaskets are in good condition and no leaking fuel from the pump. I can't think the needle and seat(in carb) are sticking because I've had that apart and pressure tested it. As well as noticed the float travels freely. I've inspected all fuel lines for leakage and cleaned the inside of my tank out thoroughly.

There is a line I am unclear of what it is. It runs from the engine block above the fuel pump to the intake manifold on the lower left hand side of the manifold. I believe it to be a re-circ line or would it be a vaccuum line for leaf/reed control?

Regardless I am at my wits end. I will try a loaner fuel pump tonight, wait for my kit to come and repair my own. I have borrowed a tank to ensure that it was not my fuel line from tank to motor supply. Although I am not totally convinced that isn't it either. Either way, can you guys think of anything I've over looked. I am frusturated and could see how I could look past something simple.

Sorry about the venting.
 

Palssonater

Seaman
Joined
Jul 3, 2007
Messages
60
Re: '84 35HP Evinrude Troubles (STILL!)

Nothing? I guess I must have it covered then eh?
 

BF

Lieutenant
Joined
Apr 8, 2003
Messages
1,489
Re: '84 35HP Evinrude Troubles (STILL!)

How does it die? Does it do the fast/slow thing like it's running out of gas? or does it just plain die from WOT? If the later, I'd be thinking that it might be electrical. Also, I don't know what to think about the fact that it started last year on the 3rd pull without primer... Does it also have choke? I'd think that an OB that cold starts without choke/primer is set up to be running too rich at idle at operating temp. Your description of having it easier to start when you disconnect the fuel line to the carb also suggests that maybe it's flooding. But maybe that's fixed when you disconnected the leaky primer (?). Maybe try adjusting the float level down so it closes sooner (?). I don't think I'm being much help to you, but these were my thoughts from your post anyway...
 

Palssonater

Seaman
Joined
Jul 3, 2007
Messages
60
Re: '84 35HP Evinrude Troubles (STILL!)

Thanks BF.

No this motor does not have a choke. I will be repairing the primer. That whole assy. costs like 60 bucks US though. WOW! I think I will try and see if it is just the orings for a cheap fix. Otherwise, this countryboy will just use a squirt bottle into the carb. lol.

The motor does not completely die out. That's why I think it is a fuel issue. I understand the complete loss of spark would mean electrical. I am able to save it most times from a stall if I just slow up on the throttle and re-prime the ball as it is way to soft.

As for setting the float, do I just bend the piece of metal slight to make it sit lower in the bowl? I would imagine that's how to do it, while maintaing the spot where the needle clips to it. Use a straight edge for a clean bend. I will try that if my pump replacement doesn't work out for me.

Thanks for the reply. Keeping my head level is hard to do and its easier with advice. :D
 

iwombat

Captain
Joined
Jul 12, 2006
Messages
3,767
Re: '84 35HP Evinrude Troubles (STILL!)

The primer bulb should be soft once you're under way, it's just part of the fuel line at that point. You may want to double-check your fuel lines for an air leak and make sure your tank is venting properly. Also, give your anti-siphon valve a once over. A good way to eliminate all this is to try and run it with a portable tank and different hose. If that doesn't change anything, then start suspecting the fuel pump and carb.
 

BF

Lieutenant
Joined
Apr 8, 2003
Messages
1,489
Re: '84 35HP Evinrude Troubles (STILL!)

it doesn't take much effort to adjust the float level. The little metal tab where the float connects bends easily enough with little force. If you have the carb off, and the float bowl off the carb, hold the carb upside down. The float should be level with the carb body, and about even with the height of the gasket (which should remain on the carb body). To lower the float level, you'd tweak it so the float is a bit higher (when it's upside down). That would mean when it's right side up, the needle would be closed earlier. Check to see where yours is... sometimes when you put a new one on, it needs to be tweaked to be level.
 
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