56' 7.5 Evinrude Fleetwin High Speed Problem

[PaulyV]

I just changed the coils/points condensers as they were original to the motor. I have had it on the lake for 6 hour days of trolling with no issues.. Heres where I am stumped. When i get more than half throttle it wont achieve the rpms it should. By ear I am missing 2500 rpm. The boat wont really "get up and go" It pushes rather than jump. when I get to half throttle it cruises well. I have adjusted the high speed needle and the motor isn't rich or bogging down, it just wont "rev" up. In neutral it runs the full spectrum of rpms and sounds amazing. Plugs gapped at .030. Points .020 fuel 24:1. Can this be the carburator? Thanks ..first time poster..lifetime boater...

 

[freddyray21]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

make sure the spark is good on both cylinders, check compression and see what you have. Did you adjust the high speed needle on the boat? They will act different under a load. If all of that is good you may be looking at a carb overhaul. Not hard to do

 

[F_R]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

I'll bet you are running on one cylinder. Either your ignition project needs a re-visit or there is something basic wrong with the powerhead. Check for 1/4" spark on both wires, Check compression, Check for water in the cylinders.

And stop revving it up in neutral. You want to scatter it all over the area?

 

[PaulyV]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

I will pull the plugs and test compression..thats what I was leaning towards, I have double checked the install of the ignition and its fine. Just to be clear, I am not revving in neutral for fun..I have adjusted high speed while running in gear on lake. I achieve good results in smooth engine response just no top end. Thanks for the advise and I will try the compression test.

 

[Joe Reeves]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

When you are sure that compression is okay, that you have the proper spark on both cylinders, and that the carburetor is clean, adjust the carburetor as follows.

(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)

Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.

Setting the high and low needle valves properly:

NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.

(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.

(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

 

[freddyray21]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

try a new set of plugs also. even if those are new I have seen one plug bad. You can also get it running then pull one plug wire at a time to see if one is bad.

 

[itsaboattime]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

Hey Joe..........In the past 3 days I think I've seen you post your carb adjustment sequence about 7 or 8 times. I think I have it memorized....

It's a great thing to know. Got a feeling it'll come in handy.

 

[PaulyV]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

Joe..Interesting thing you mentioned. 1st thanks for the detailed information. I have the low speed set 1.5 turns..and am able to have it tweaked to idle for a nice day fishing. Heres whats odd. I have my high speed set at 4..from lightly seated. It will NOT turn a full revolution, it only will move half turn from lightly seated. Can this be a problem. Bottom dial reads 1-5..I can turn from say under the 1 to just over the 5..about half turn. As of this evening I have not been able to check the compression. I plan to troll this Sat..as the weather will be 70-75 here in CT.

The backround on this motor is, found it in a pile of garbage that was being thrown out. Paint is a 7 out of 10 emblems stickers are 8 out of ten. I began fishing with this year motor since I was 3 years old on Bashan Lake, East Haddam CT. My grandfather lost the motor in the lake back 20 years ago. So I was fortunate to find the same one. I have his 62 starcraft 12' and having this motor attached really makes my day out on the water. Fond memories. So I will trouble shoot as advised.

Glass bowl is clean although I understand the float may be gummed up/ filter a bit worn. Never touched the carb yet..I am fortunate to have her on the water..
Thanks Again everyone!

 

[wbeaton]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

Joe..Interesting thing you mentioned. 1st thanks for the detailed information. I have the low speed set 1.5 turns..and am able to have it tweaked to idle for a nice day fishing. Heres whats odd. I have my high speed set at 4..from lightly seated. It will NOT turn a full revolution, it only will move half turn from lightly seated. Can this be a problem. Bottom dial reads 1-5..I can turn from say under the 1 to just over the 5..about half turn. As of this evening I have not been able to check the compression. I plan to troll this Sat..as the weather will be 70-75 here in CT.

Do you mean to say that the knob stop on the air silencer is stopping you from turning the high speed knob out? If so, remove the cowl and stops (there should be one for each jet) and try adjusting it again. Or just take off the knobs and reposition them past the stoppers. You have to set the high speed before the low.

 

[PaulyV]

Re: 56' 7.5 Evinrude Fleetwin High Speed Problem

Thanks to everyone for their help. I found the issue. The high speed needle looks as if someone used it for a javelin throw. Badly shouldered. Everythings ok. Thanks again.