took apart second head, need some help

[fishingdave]

well i took apart the port side head and notice that there is damage to the top piston and the bottom one seems fine. On my starboard side the bottom piston is the damaged one, could it be that one of my carburators were running lean? which carburator controls what pistons ?? I have a 1989 v-4,and all the help would be great, here is a link of what i have so far and thanks for all the info on my last post.<br /><br /> http://supercool3598.tripod.com/johnson/index.album?i=2

 

[Dhadley]

Re: took apart second head, need some help

Like I said in your original post, looks like typical coking damage. Broken rings. I'll bet the motor was propped out in the low 5000 range.<br /><br />It should be very borable. The rebuild kit you mentioned in another post and a couple of heads and you'll be ready to work on the set up to avoid it hapening again.<br /><br />If you like the motor, it should be a very worthwhile project.

 

[fishingdave]

Re: took apart second head, need some help

thanks dhadley for the info, the motor was propped out for lower torque insted of high speed, what would be the correct prop for this motor with a 18ft glassmaster center concole?<br />Also what causes coking damage?

 

[Dhadley]

Re: took apart second head, need some help

The correct prop will put the wot rpm's at 5800 with an average load. Coking is promoted by high combustion temps. Most likely from lugging the motor.