Stalling problem question.

[johnm]

I've got a Envinrude 55HP 1979 two stroke engine with an ongoing stalling problem. <br /><br />My engine is fine and runs great in all gears and full speed when COLD. When the egine warms up though and I make my way back to the ramp back from a fishing trip these are my symptoms:<br /><br />1. In gear doing about 5 knots, I am able to drive the boat through a marine channel which is about 150 meters long back to the ramp. Don't have a problem at this stage, even though egine is in gear at low speed. I have to do 5 knots, otherwise I'll get booked!<br /><br />2. I park the boat and switch the engine off while I go get the car and trailer.<br /><br />3. Back the car up, go back to the boat and start her up. Engine starts up fine, but when put into gear, stalls. Stalls in reverse too. This does not happen when engine is cold. <br /><br />If the engine is left running whilst I go grab the car, it seems to run quite rough, in gear, but doesn't stall as much. I can get boat back onto the trailer with 1 or 2 restarts, rather than 15!<br /><br />A few people recommend rebuilding the carbs, but wouldn't this problem occur when the engine is cold too if it was fouled carbs? Ie. Why is it ok cold, but not hot?<br /><br />Regards,<br /><br />JohnM

 

[alcan]

Re: Stalling problem question.

Hi John<br /> It sounds like it may be tune up time. There are lots of things that can cause this condition. Might be a bad fuel line connector,crud in the fuel system (including carb). Could be a linkage adjustment. When loading the boat after restart,do you allow the motor enough time to clear it self?

 

[ob]

Re: Stalling problem question.

JohnM,Symptom sounds to me as if you need to perform a link and synch on carb linkage.<br /> You can do a quick visual on a couple of things to see if they are in line.<br /><br />1 - With throttle lever in neutral check to see that linkage roller is aligned with scribe mark on fiber cam and just touching.<br />2 -Remove intake cover and insure that carb flaps are fully closed.<br />3- Actuate throttle control through various positions and insure carb flaps are opening equally and fully horizontal when at WOT position.<br />4 - Return control back to neutral position and inspect that flaps are fully closed and linkage roller returns to scribe mark and just touching.

 

[johnm]

Re: Stalling problem question.

Alcan, what do you mean by "allowing the motor enough time to clear itself"?

 

[alcan]

Re: Stalling problem question.

Hi John <br /> Most two stroke engines recive the air/fuel mix from the carb into the crankcase. Then under compression from the pistons down stroke, this air/fuel mix is sent to the cylender via a by pass. Since the fuel dosen't go directly to the cyl. we must first fill the crankcase with the proper air/fuel/oil mix. Normaly when starting a cold engine we richen this mix by choking/priming. This is because the crankcase already is full of air. Some times we prime a little too much or not really enough. This will cause an over rich or lean condtion. I takes most engines several seconds of run time to cycle through or clear this non-ideal mixture. If we don't allow for this to happen and start throtling up and down it just adds to the problem. Sometimes we tend to get in too big a hurry at a busy ramp. How ever I don't think this is your total problem. As I noted earlier it's tune-up and service time. Make sure what OB suggests is included.