7.5 hp Ted Williams - does not run fast.

Hi all, I'm new to posting here, so bear with me! I have come across a sears ted williams 7.5 horse low profile motor. Serial # 700325R13-5092, Model Number 574-59950. I understand from reading other posts that this is a McCulloch powerhead that is air cooled, with the exhaust being water cooled. The motor seems to run OK, but it just doesn't seem to get up into the high rpm range when it is in gear. When it's in neutral it screams, but when it's in gear, it bogs down, and occasionally sounds like it's trying to go faster, but it misses and then bogs down again. Is there anything that anyone would suggest trying or doing that might correct the problem? I'm very new and green to the whole outboard motor maintenance game, so speak easy and dumb to me! Thanks in advance for all your help!

Re: 7.5 hp Ted Williams - does not run fast.

You are correct it is a McCulloch but it is water cooled.Eska 1 cylinder motors are aircooled/water cooled.
Two things typically
cause poor performance.A dirty fuel system. Or poor ignition.
You wouldn't be the first one to not realize you were running on only one cylinder.
Check for spark The ign. system is similar to any small motor of that era.
You may find an aftermarket service manual at the library.It will cover many brands below 30 hp.Usually the first few pages cover basic motor systems design.

Re: 7.5 hp Ted Williams - does not run fast.

Stelespike is correct but try this. Go to the carb and find these little screw things. These are called fuel jets and they control how much fuel gets injected into the carb. Turn the jet all the way in until it does not go any farther in but not cranking it in. Do it SLOWLY. Write down how many times you screwed it in and then unscrew it, clean it, and then screw it back in, and then turn on the engine. When you get the motor running, turn the jet in or out until it sounds like it is right. Hope this helps.
Colin

Re: 7.5 hp Ted Williams - does not run fast.

Thanks to both of y'all for your help. Figured out what the problem was. The throttle linkage was broken, leading to the butterfly valve not opening under high RPM, and the motor wanting to stall out at higher speeds. Fixed it and it ran great until...the motor overheated! Apparently a few wasps decided that the motor made for a lovely starter home and moved in, causing the motor to overheat. So, now I have to get a new impeller, and figure out where the dead wasp obstruction is. Or...find a new motor that might have a little less maintenance needs than this one. Also, while all this was happening the pull rope broke and I have not been able to find a replacement that will hold up to the demands that the old one did. Anyway, diarrhea of the mouth. Thanks guys!!!

Re: 7.5 hp Ted Williams - does not run fast.

gcj2008 said:

Thanks to both of y'all for your help. Figured out what the problem was. The throttle linkage was broken, leading to the butterfly valve not opening under high RPM, and the motor wanting to stall out at higher speeds. Fixed it and it ran great until...the motor overheated! Apparently a few wasps decided that the motor made for a lovely starter home and moved in, causing the motor to overheat. So, now I have to get a new impeller, and figure out where the dead wasp obstruction is. Or...find a new motor that might have a little less maintenance needs than this one. Also, while all this was happening the pull rope broke and I have not been able to find a replacement that will hold up to the demands that the old one did. Anyway, diarrhea of the mouth. Thanks guys!!!

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You need the hard braided nylon for your pull-starter. Any good hardware or farm & ranch store should have it----just be sure you get the same diameter by taking along a piece of the old one.

For future reference------
I really enjoy 'fooling around' with old outboards. I love reviving them and hearing them sing once again after a long neglected sleep. And they take me fishing---from a '48 Gale 3 horse and '46 Johnson TD-20 5 horse to the newest '86 Eska on my racks---and bring me home dependably. But being on an extremely limited 'fixed income' (Beaurocratese for 'Broke and needs to be fixed".) I don't like spending anything that isn't absolutely necessary to get them dependable. The one thing that I check FIRST when they finally get to the testank stage is the waterpump! As soon as a motor is running well enough that it isn't about to die for lack of my undivided attention I check to see if it's pumping like a firetruck----if not then I shut it down----THEN! And I continue to check it intensely and often thereafter until it has proved its dependability to me. I usually pull the L/U and visually inspect them as well---if the rubber is time hardened, has a pronounced 'set' or displays any evidence of cracking where the vanes meet the central body of the impeller then I wait until I can afford to replace it before using the motor on a boat.

Plenty of the right oil in the fuel mix and a new waterpump impeller are the best---and ONLY---insurance you can get for old outboards! Tom