1960 75 HP or 1965 60 HP Jonny Fires up wont run.

[James R]

After cleaning the carb and doing all the right stuff, points, timing, sync, plug wires, it seemed to run good. But the water pump seemingly was not delivering.
Pulled the lower and did the kit thing. Put the lower back on but found that it would not go all the way in by pushing. Did all the measurements and everything was in order. Put it down to tight seals and carefully pulled it in with the bolts.
Now we have a motor that will, with effort, started up but it only ran briefly and after some fiddling could get it to run for some minutes before it died. Motor temp is way too high anyway. Checked the set up again. Seems like fuel starvation, took the carb off again and checked everything. The needle jet was a bit sticky but no crud.
Cleaned and freed it up. Pulled the out hose from the fuel pump and turned the motor over. Fuel pumps all over the place. Corrected a kink in the line to the carb.Tried it with choke, without choke. Tried adjusting the slow running mixture,1.5 turns up down, didnt make any difference.
What haven't I done?
Got any ideas fellas? Help!:|

 

[tashasdaddy]

Re: 1960 75 HP or 1965 60 HP Jonny Fires up wont run.

will what engine is it. model #. did you check compression.

 

[James R]

Re: 1960 75 HP or 1965 60 HP Jonny Fires up wont run.

We dont know which of the two motors it is but from research there is not much difference. The 75 HP has bigger bore diameters. Compressions looked good, surprising for its age. After doing all the stuff, prior to pulling the lower and relacing the water pump, it fired up and ran nicely. When it fires now it runs nicely but briefly.

 

[tashasdaddy]

Re: 1960 75 HP or 1965 60 HP Jonny Fires up wont run.

did you look for a disc like this, has numbers on it.

http://i46.photobucket.com/albums/f119/tashasdaddy/MVC-859S-1.jpg

go to your 1st post , and hit edit in the drop down on the left. take the years and hp out of the title then add that info into the body, that you don't know. people see titles like this and some avoid them. if you can find the disc, and number we'll know what you have.

 

[steelespike]

Re: 1960 75 HP or 1965 60 HP Jonny Fires up wont run.

Sometimes if there is too much grease on the drive shaft spline it won't let it slide into the crank.
If shes hot you may want to double check the impeller
sometimes the center fails.After assembling the pump turn it by hand.If running in a tank be sure the pump is well submerged.
You need to check spark when it quits.If it has spark
then in my mind for some reason it can't supply gas.
When the motor is off if you squeeze primer bulb it fills the carb.It then starts and runs but little or no gas is supplied.My guess is some sort of float problem sticking closed,closing early.If it is sucking air at some point between tank and pump it may prime but not be able to supply when running.Though not likely because you had good delivery at the pump outlet.

 

[James R]

Re: 1960 75 HP or 1965 60 HP Jonny Fires up wont run.

Thanks for the responses guys. In answer to the question on model # the only number on it is on a disc
in top of the block port side and has the usual M with the number J2398505. No other numbers except what appear to be part numbers in the various castings. The motor is the old white color.
I will pull the carb again and the lower unit. No big deal to do this and check everything. Sure sounds like fuel doesn't it. Didnt have a lot of grease on the shaft but there may have been a bunch from previous times.
This is a nice old motor and worth a bit of effort to save it.
Appreciate all the good info.d