To Dhadley

[Bluefish]

I was reading your advice to kaino, and the talk with dunk, and I wondered what you think the rpm on a 150 1990 evinrude pushing a 20ft G/W about 4100lbs at wot should be.<br />Thanks

 

[Dhadley]

Re: To Dhadley

We found that the crossflow motors have reduced combustion temps when capeable of 5800 RPM at WOT with an average load. Anything you can do to keep the combustion temps where they need to be will extend engine life. Using fresh 87 octane, good oil at the correct ratio and Champion plugs combined with the proper RPM should keep the temps in the correct range. <br /><br />Good luck!

 

[Bluefish]

Re: To Dhadley

Dhadley<br />Boy you guys like the high rpms wow best I ever had 5600 when she was new and trimed to the max, must of the time we have a nasty chop here, do you run on lakes ??? know I run 5200/5300 wot I put that on the replacement prop michigan it was never the same...Anyway I also wanted to ask you about the plugs I see you always say champion plugs I swicth to ngk plugs br9hs-10 .40gap years ago because of champions qualty problems, bad plugs quick breakdown etc. I fond the ngks would last two seasons if I wanted to. ??????????????<br />Thanks

 

[Dhadley]

Re: To Dhadley

I very seldom run any of my motors at WOT for extended periods because of water conditions but I like to make sure they are capable of the top RPM. Sometimes we do run at 5800 RPM, or more, for extended periods. The point is to not "lug" or over prop an engine. Look at an 2000 Evinrude / Johnson accessories catalog on page one. That is an example of coking damage resulting from too much carbon build up. <br /><br />I stick with Champion plugs, in stock OMC motors, because that is what the manufacturer has calibrated the motor to run with. Just like Mercs and Yamahas are set up for NGK's. If you have had good luck with them then I would certianly think you should stick with them.<br /><br />Good luck!