pulling flywheel 1961 40hp Johnson

[OCboat]

Re: pulling flywheel 1961 40hp Johnson

I just started a thread a few days ago about my '66 40hp being very hot to the touch with the thermostat installed. This is a new t-stat and I tested it to make sure it is working properly so I guess this is how these old motors run. It is a little scary when the head is too hot to touch for more than a brief second. The head stays cooler when I run it with the t-stat removed and it spits much more water.

 

[royal0014]

Re: pulling flywheel 1961 40hp Johnson

I just started a thread a few days ago about my '66 40hp being very hot to the touch with the thermostat installed. This is a new t-stat and I tested it to make sure it is working properly so I guess this is how these old motors run. It is a little scary when the head is too hot to touch for more than a brief second. The head stays cooler when I run it with the t-stat removed and it spits much more water.

Both of you need to do some research, and find the root cause of the heat issue. It may be deeper than the t-stat. Running without it is not the answer, and running w/o will shorten the life of the engine.

I don't know the 'operating temp' of the engines, but use one of those non contact laser temp doohickeys and check it out. Maybe things aren't as hot as you think. I know my hand isn't calibrated


<<)))(((>>

 

[freddyray21]

Re: pulling flywheel 1961 40hp Johnson

with a thermostat they will run hotter then a motor that does not have one. That thermostat is I think designed to open at 143 degrees. Just FYI according to health department standards hot food on a buffet line has to be 140 degrees.

 

[wilde1j]

Re: pulling flywheel 1961 40hp Johnson

SS is fine and better than copper if motor is a saltwater one. Metal is the key.

 

[ward cleaver]

Re: pulling flywheel 1961 40hp Johnson

I think the reason most all parts desks sell the SS in this area is because you never know whether or not a motor is going to end up in salt water. And if SS is better at fighting corrosion and works as well as copper, then why not use it? If I were in Kansas, I would use copper if only to stick with the original old school design specs.

Regarding the t-stat, I know there is quite a debate on ditching the t-stat. You can easily find lots of folks on both sides of the issue. I know I feel more comfortable seeing a steady flow of water from my outboard.

 

[kfa4303]

Re: pulling flywheel 1961 40hp Johnson

hi ward. glad you making headway, but keep the t-stat. it was designed to have one, and when proerply installed, it should not effect water discahrge in the exhaust in any way. you can get one here at iboats for about $15.

 

[registeroot]

Re: pulling flywheel 1961 40hp Johnson

hi i have a 1961 40hp and would really appreciate it if you could manage to post pics! thanks. check out my thread on here if your interested, im just at a different stage to you, i have a new impellor fitted, lower unit reinstalled and gears synced with shift rod. im waitning for a torque wrench from my friend before i torque the flywheel back on. i would like to know exactly how to test coils/ignition prior to reinstalling flywheel if at all possible?
i have a multimeter, just dont know what to do! thanks.

 

[Tim Frank]

Re: pulling flywheel 1961 40hp Johnson

hi i have a 1961 40hp and would really appreciate it if you could manage to post pics! thanks. check out my thread on here if your interested, im just at a different stage to you, i have a new impellor fitted, lower unit reinstalled and gears synced with shift rod. im waitning for a torque wrench from my friend before i torque the flywheel back on. i would like to know exactly how to test coils/ignition prior to reinstalling flywheel if at all possible?
i have a multimeter, just dont know what to do! thanks.

You can do a search in these forums and find a wealth of info on ignition testing and servicing....or just read this entire thread....there are links galore....

http://forums.iboats.com/showthread.php?t=511599&p=3446234#post3446234

 

[ward cleaver]

Re: pulling flywheel 1961 40hp Johnson

Took the boat out to the lake yesterday and the motor ran like a champ!! I forgot my GPS so I don't know what speed we were able to make but it sure looked good to me. Next time out, I'll have to remember to bring it.

About the t-stat -- without the t-stat I get a very strong stream of water that is not too hot on my hand. With the t-stat, I get more of a mist that is almost too hot for my hand. I am reluctant to let it run very long like that because I don't want to burn up a head gasket. But maybe that's the way it is suppose to be. I have been letting it run with the t-stat for about 1 or 2 minutes before getting worried that I am causing a problem.

I know the spec is to have the t-stat and that running it under-temperature is not optimal but I don't want to cause an even bigger problem that will require major surgery to fix. I know I am moving plenty of water with the water pump and the t-stat is new. So the question I have -- is my cooling system running as designed? How much water should I be moving when the motor is warmed up to operating temp (with the t-stat)? How long should that take? It seems like it is never getting passed the by-pass mode where the t-stat is still closed and producing only a hot mist. I suppose the t-stat could be bad. I could put the old one back in and give it a try easily enough.

BTW I can hardly believe how quiet this motor is. Right there on the side of the motor is a decal that says Super Quiet but for 40hp it really is amazing how quiet it is while generating so much power.