how much piston slop is ok? and how many hours should pistons last?

[adam98]

I have a 1975 115 v4. hour meter is discontected and reads 800hours. 100% untouched factory motor. besides carbs rebuilt.
all 4 cly read 120psi , but when plugs are out you can use a screw driver to move the pistons. seems to have a goog bit of slop. should i worry about what seams to be 1/16 or more slop? on all pistons... i would hate to break a skirt off one of the pistons at 6000rpm
what should new rings read?
should i keep running this motor and go thourgh it this winter?
do i need to change the pistons?
also if i see some pitting on the piston that is likly pre detination correct?

i run my motor at 5500wot 75%of the time to get across the lake and use my electric trolling motor fromthere

and why when I tell people you have a johnson there give you a look like the motors are no good? seems this motor runs like new and pushes my 78 ranger 45mph across the lake........

 

[Haffiman]

Re: how much piston slop is ok? and how many hours should pistons last?

2000++ hours on pistons if running commercial, is no big deal! In running time, yours are just finished break-in time.
Piston rings a bit different as they loose tension over time.
Biggest danger are seals and gaskets. To be on 'safe' side, re-seal the engine every 10 years, and then even your great grand children might enjoy the engine!!

 

[boobie]

Re: how much piston slop is ok? and how many hours should pistons last?

Piston slop is normal on that mtr. As long as you don't hear any noise out of the power head when it's running, keep on going.