73 Johnson 115 binding when starting

[Fair Boater]

Motor ran great one week ago. Still burning previous owner mixed fuel (24:1), less than two weeks old, mixed w/ Johnson oil. Motor now turns over VERY hard, sometimes stopping starter rotation. Even when turning flywheel by hand, motor can bind completely, but inconsistently. Back off from bind, and can turn flywheel or try starting again. Rebuilt starter (bad armature) and NEW battery have been installed. Occationally tries to start, but eventually binds and dies. Seems to want to bind more as you turn it over more. Ideas on where to look? This is my first boat, but I'm very interested in doing work myself (great w/ motors, etc.). I've poured over motor manual, but would like an opinion or two before jumping in too deep, perhaps without having to. Appreciation for any help in advance....<br />Bummin' Bob with a Bindin' Boat

 

[MGuckin]

Re: 73 Johnson 115 binding when starting

Frequently, binding is caused by improper initial timing.<br />Fuel enters the cylinders, compresses but will not ignite.<br />If you can turn your motor freely with all of the spark plugs out,try checking your timing linkage adjustment.

 

[Dhadley]

Re: 73 Johnson 115 binding when starting

When turning the flywheel by hand the plugs should be out. If it still binds, and its still inconsistant, drop the lower unit and try turning the flywheel again. <br /><br />Why are you running double oil? What spark plugs are you using? When you pull the plugs do they all look the same?<br /><br />Good luck!

 

[Fair Boater]

Re: 73 Johnson 115 binding when starting

MG and DHadley,<br /><br />Thanks a ton for the advice - the binding was caused by a lower unit that had a hole worn between the water sleeve and oil compartment in the unit. Oil out, water in, no lube and heat help, dead lower unit. Shreads of metal all OVER the place! <br />Replaced lower unit and all is good. I also learned how to properly check for oil. I understood from an additional thread I wrote that there is no way to place a sensor for the lower unit oil.<br /><br />Thanx again for the help... I feel like I LIVE in these forums...<br /><br />Better Boatin' Bob

 

[Fair Boater]

Re: 73 Johnson 115 binding when starting

DHadley -<br /><br />To follow up on your questions of plugs, oil mixture, etc.<br /><br />I have learned the proper 50:1 ratio with approved TC3 OB oil, and the motor runs MUCH better than it did before I had the lower unit problems. <br />Plugs were correct, motor top and bottom units tested VERY well, according to the place that installed the lower unit. They explained a ton of little things to me, and I feel much better about what to look for/do/expect with my new investment.<br /><br />Again, thanks for the advice - I'm always looking for more!<br /><br />Bob