1950's Montgomery Ward Misses at high RPM

[crapola82]

I have two engines, one johnson sea horse, and one montgomery ward sea king. They are both 25hp, and when the covers are off they are identical motors (except for the fuel delivery system). I believe they are both from the 1950's. My problem is with the MW. When idleing, it runs like a champ and when at high speed, the motor misses and bucks really hard. It does this every few seconds while at high speed. Is the problem with a possible fuel/air leak, or ignition?

 

[Mod2]

Re: 1950's Montgomery Ward Misses at high RPM

Moving to Other Outboard forum.

 

[joaklay]

Re: 1950's Montgomery Ward Misses at high RPM

The first thing I'd check is the ignition coils as with age, they crack badly and cause high speed power loss. Ign wires may also be NG.

 

[steelespike]

Re: 1950's Montgomery Ward Misses at high RPM

When you say "bucks really hard" does it seem like you hit something?If so you may have a worn clutch dog.A fairly easy repair if mechanically inclined.<br /> You should work from a manual.You may find one here or try the library.

 

[jch7450]

Re: 1950's Montgomery Ward Misses at high RPM

Yep, i'd look at the plug wires, coil ect.<br />How old are the plugs in it?

 

[tmcalavy]

Re: 1950's Montgomery Ward Misses at high RPM

What they said...check the condition of the coils plugs and wires. Generally a bad coil will start to drop out when the motor reaches running temp, especially at high speed. If the coils/wires are good, check the clutch dog...if it has a shift. Some of the early 50's models were direct drive, later went to a neutral clutch (with forward and N only) and later went to F-N-R shift capability. If it physically bucks, like jumps, it's probably a lower unit problem...if it just sneezes and starts cutting out you need to adjust the high speed carb jet/needle. If its a 50's model outboard it has two carb jets...high speed (largest/longest needle) and slow speed (smaller). Get it running and let it warm up. Turn the high speed needle clockwise gently until it just seats/closes...don't force it after it stops turning. The motor will choke out and die by then. Back it out 3/4 to 1.5 turns counterclockwise, restart the motor and run it up to speed past idle and into Fast. Adjust the needle either way until you find the sweet, smooth running spot. Note about how many turns out this is...this is your baseline setting. Now idle it down and do the same with the slow speed jet/needle...it won't be as sensitive. Find the spot where it idles best and accelerates smoothest. Your old outboard is now properly carb tuned...provided the carb is clean to begin with. Good luck.