1962 Evinrude Lark 40HP Selectric Shift Power Problems

[Woodonglass]

Starts and Idles Great! When I try to go to WOT she only goes to about 30% and thats it. Does not appear to have a miss. I will be checking compression this week. 2 weeks ago I ran her for about 15 mins like this and she finally broke loose to WOT and ran great. I throttled back after about 5 mins, and she would not go back to WOT. Pulled her out and she started puking "Gassy Oil" out the bottom of the lower shroud. Pulled the shroud and it appears to be coming from mid point or higher on leg. I'm thinking maybe a stuck float or crap in the carb but fuel filter and bowl do not appear to show to much trash.

Help!!! Less than 4 hours on Total motor tune up including Carb rebuild, ALL seals (Upper and Lower), Plugs, Points, Condensers, Mags, you name it they got replaced with NEW!!! She ran Great for the first couple of outings and then this started. I'm NOT a motor guy so I'm looking for some advice on where to start. My B.I.L. did all the work on restoring this motor 2 yrs. ago but since has moved to Virginia so I don't have his expertise except by phone. Any one with experience with this old motor would be a blessing!!!!

 

[Daviet]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

Is it running on both cylinders, didn't loose spark to a plug did you?

 

[Woodonglass]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

I have Strong Spark to both cylinders.

 

[Daviet]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

Well, if the compression checks out, the only thing left is a fuel delivery problem. Maybe a piece of trash flushed out of a fuel line into the carb.

 

[Woodonglass]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

Yeah, I'm going there next. If you run it like that for a while would that cause it to puke the "Gassy Oil" mixture??

 

[Daviet]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

Yes, if a cylinder will not burn the fuel mixture, no spark or low compression, the fuel mixture will go into the exhaust system and make a mess.

 

[Woodonglass]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

Alrighty Then. Got a place to start checkin! Thanks Daviet. Maybe, I'll get to be some kinda Meck - A - Neck before I quit messin with this old boat!!!!

 

[kfa4303]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

Hi Wood. Do you have full range of motion on your throttle control? Are all of the cables/linkages ok? Perhaps it's as simple as something binding up somewhere. When you say the motor finally kicked in after 15 min on the water to achieve WOT, did it feel like your gears were finally engaged more firmly, or did the motor pick up in rpms? It sounds like all of the motor's components are ok, but these old Selectric drive motors can be quite finicky causing you to have a motor that will "run" fine, but won't "go" very well. One simple test to determine if its the powerhead vs. gears is to take a pair of insulated pliers and individually remove the spark plug boot from each cylinder one at a time as the motor is running. If you pull the lead and the motor drops in rpms/dies, that's good. It means the cylinder was firing properly. However, if you pull the lead and the motor runs the same, that means it was not firing correctly to begin with. The excess, unburnt fuel in the exhaust is yet another sign that one of the cylinders may be on the fritz, whereas fuel coming out of the front of the carb is indicative of flooding, which doesn't seem to be your issue. Also, be sure that you're using Champion J6C or J8C sparkplugs. Alternate brands can't often cause issues despite what the guy at the store says. Large drop offs in power are usually do to a dropped cylinder, but the selectric drive complicates things. Unfortunately, I don't know much about them myself. Aside from the fact that they require special grease/lube and battery to work properly. You may want to double check the charge on the battery used to change gears. Perhaps it's a bit weak and causing poor gear engagement, or something along those lines. Keep us posted.

 

[Woodonglass]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

Throttle is A-OK. Button Shifter Working fine and gears engaged. It really appears to be either a fuel or cylinder issue. I'm starting to lean towards cylinder. The puking of Gassy Oil makes me think she's not firing right so, I'm gunna really pursue that line of attack and see what happens. Buying a Compression Checker today and also check the fire. New Champion J6C's so That's not the issue. Might be a dirty carb since my old tanks could be puking but I checked the pickup and it's filter was clean, I had just installed a NEW inline fuel filter and the Carb Glass bowl was running clean sooo.... I'm really thinking I dropped a cylinder for whatever reason. I guess I'll find out soon enuf.

Thanks to both of you for your input

 

[kfa4303]

Re: 1962 Evinrude Lark 40HP Selectric Shift Power Problems

Fresh gas never hurts, but it sounds like the fuel system is ok and the dropped cylinder could certainly cause the unburnt fuel. Does the motor have a kill switch? Perhaps it's shorting and cutting in/out intermittently.