1985 40 HP Nissan, locks up

[Crazy Joe]

I was going a long and the motor stopped.It would not tune over,I tryed it again after a while and it fires but stopped dead again after a few seconds. Could the piston rod bearings be shot? I have no metal filingd in the cyclinders
Any thoughts??

 

[pvanv]

Re: 1985 40 HP Nissan, locks up

Some more information would help us help you. Having your precise model for this 25-year-old would help. Trying to diagnose the problem from your description could lead to almost anything.

Did this problem just start recently, or have you had problems like this for some time? Are there any indications of overheat? Is this an electric start unit? When it fails, is it seized, or can it crank, even if it does not fire?

If in fact it did lock up -- seize -- then you may have been operating without TCW-3 oil in the fuel, or you may have severely overheated.

On the other hand, if it is merely a stalling issue, especially one that improves after sitting, it could be as simple as not having the vent open at the fuel tank, or a bad o-ring at one of the primer hose connectors.

 

[Crazy Joe]

Re: 1985 40 HP Nissan, locks up

The Motor Is a
NS40C
Other Numbers
361A-1 65991

It ran fine I don.t think it's over heating ,the water is spewing out of the pee hole just fine, I have the proper mix ,it says 40-1 but I do 32-1. I changed the lower end oil.
?
Thanks for the reply.

 

[pvanv]

Re: 1985 40 HP Nissan, locks up

Ok, so it is not locking up. It is stalling. Time to do basic troubleshooting. Get out the Factory service manual, and go through the fuel, ignition, and mechanical systems (likelihood of problems are in that order).

You may be starving for fuel, for instance, but you need to check for that condition.

If this seems a bit beyond your skills, best to get to a dealer.