Problem again ! Chrysler 55hp

[ac439]

So after rebuilt carb, fuel pump, idling adjusting and repeated testing on driveway, I went out to the lake with a boating friend last week. Engine started right up, things went smooth and we were on the lake for an hour and returned home. We didn't stop the engine during that whole hour.

With last week's good experience, I took the family out to the same lake today. Engine started right up and we were cruising on the lake for 15-20 mins before we decided to stop at the middle of the lake and fish. So, we did fishing for about an hour.

Then the engine won't start (it would crank). After fiddling for about 3 minutes, the wife pointed to the MinnKota. I had no choice but hooked it to the starting battery (last time went so well so I didn't bring the deep cycle). the 50lb trolling motor definitely pushed all 4 of us back to the ramp in about 20 minutes but the trip was like forever.

I tested the motor on driveway many times, shut off and restart without problems. It's just at the lake where the problems will come. Other than unable to restart, the engine runs strong and idle fine. I don't know what else I need to do. I have noticed the engine seems to run differently (weaker) when the engine cover is on. When I tested it on driveway, the cover was off. The other place that I have not messed around much was the idling mixture adjustment. I just use the settings that most of you recommend (1 and 1/4 turns CCW).

I have lawn tracter, lawn mower, gas trimmer and pressure washer all using 2 cycles engines and never ever run into this problems. I just don't understand why it is so difficult to get an outboard reliably running.

Any suggestions? - AC

 

[ck85abc3]

Re: Problem again ! Chrysler 55hp

How long have you had the motor?

How long did you try to start it?

Did it flood?

Did you wait 10 minutes and then try to start again?

 

[12Footer]

Re: Problem again ! Chrysler 55hp

I had one like that, and I came to the conclusion it was the "nature of the beast". But do not dispair, as there are a couple of tricks you need to try if you haven't already. The throttle handle has a button that allows you to give it throttle without being in gear. Push the button and PULL the handle OUT (towards the center of the boat). Push the throttle forward, (as if to take off) Sometimes the carb would refuse to take-up fuel from the bowl at idle throttle, so I had to take the handle out of gear, give it gas, start it, bring the throttle back to idle (it clicks back in), and wait a few seconds for the RPMs to settle back... But that is why they designed the throttle handle like that no doubt. I had to use it on several occasions after running, then sitting for a while.


Give that a try next time, or carry a butane refill, have somone give the carb a blast of butane, while you try to start it... But just enough to start it, as butane has no lube for the motor.

 

[Frank Acampora]

Re: Problem again ! Chrysler 55hp

Sometimes these engines run a little hot and there is no gap or heat break between them and the carb. It will run fine all day and even re-start right away. But when you let it sit, the fuel heats up and vaporizes out of the carb. Try re-priming the carb with the fuel line bulb.

BTW: I had a 55 that would run fine in the driveway but would never start at the lake. I came to the conclusion that it was allergic to water--Had to find a dry lake to do my boating. LOL

 

[ac439]

Re: Problem again ! Chrysler 55hp

Thanks guys for suggestions. I think the difference seems to be engine cover off during driveway testing but cover on at the lake. I'd wonder if the heat trapped inside the engine cover has caused vapour lock or something. But I did prime the pump again and wasn't getting any luck. I'm thinking to test the engine again tomorrow on the driveway trying to simulate the situation with cover on. At the lake, I did use the fast idle function for starting but it didn't help. Maybe I need to adjust the fast idle to a little more to help out. I'm afraid to go for bigger lakes since the trolling battery may not be able to get us back. - AC

 

[byacey]

Re: Problem again ! Chrysler 55hp

I just use the settings that most of you recommend (1 and 1/4 turns CCW).
Any suggestions? - AC

Did you actually adjust the low speed needle for proper running; or just turned it out 1 and a quarter turns? Could be you're running it too lean and it's not getting enough fuel to fire when it's warm.

 

[ac439]

Re: Problem again ! Chrysler 55hp

Did you actually adjust the low speed needle for proper running; or just turned it out 1 and a quarter turns? Could be you're running it too lean and it's not getting enough fuel to fire when it's warm.

No. I didn't adjust the low speed mixture needle. I only set it to 1 and 1/4 turns. I did play around with it a little though and found the engine speed goes up and smoother with the needle at around 3/4 turns CCW from fully closed position. But I was told that it may be too lean and may burn the upper cylinder. I also tried to get a mid-point but failed. When I turned the screw in, the engine speeded up so much so that I had to back it off. So, I got a compromise that I adjusted the idle throttle stop to make the idling a little higher but keeping the meedle at 1 1/4 turns.

If anyone can share insight on how to correctly adjust the idle mixture screw, please share your thoughts.

Thanks. - AC

 

[byacey]

Re: Problem again ! Chrysler 55hp

Warm the engine up, and with it in gear at idle, adjust needle until it runs the fastest, and then turn it out counterclockwise an additional 1/4 turn or so. You might have to adjust the throttle idle stop screw after to get the idle slow enough; should be around 700 RPM, or as slow as it will smoothly idle in gear.

 

[ac439]

Re: Problem again ! Chrysler 55hp

Ok, I did a driveway test again today. After opened the vent on top of the fuel tank, I pumped the ballon tight and the engine started right up. I let it ran for about 20 mins to full warm up. No problems at all. I did a little bit of adjustment on the idle mixture screw. Now it is about 7/8 turn CCW from fully closed position and I feel this setting gives smooth idle. I turned off the engine, put the cover back on and let it sit for an hour (to simulate the last eipsode on the lake). I went back to the boat, left the throttle at idle (not even fast idle), didn't pump the ballon and turned the key. No choke. The engine started right up, not even needed to crank much by the started. So, I shutted it off and restarted it again a few times, no problems. I waited another hour, then restarted the engine, no choke, no need to be on fast idle, no problems. The only difference between driveway test and real situation is the water level from the trash can is not as high up as on the lake. It is about 4-5" below the water level on the lake but I don't think this is the problem. I always have water coming out from the exhaust with the trash can so I know the water path is good.

I did try to put prop in gear, engine idle but I was using a trash can for water and it spilled out 1/4 of water in 3 seconds so I abandoned the idea. Maybe I need to do it on the lake.

But the driveway test today all passed and couldn't reproduce the problem. This is what driving me nuts. My son doesn't want to go boating with me anymore because for the last time on the lake, we had engine problems and he was disappointed. I don't know what to do except to keep the trolling motor on the boat and both batteries fully charged for boating.

Thanks for all the help. (Until next time.....I'm stuck in the middle of the lake.....)

-AC

 

[byacey]

Re: Problem again ! Chrysler 55hp

You really should adjust this in gear on the lake. This way the motor is under load and you can adjust it accordingly.