Compression test

[THEFERMANATOR]

Originally Posted by Destroyer

I thought that I remembered you mentioning that you used the Evinrude tuner stuff for soaking your carbs, and I meant to ask you way back then if there was any problem with it attacking the plastic carbs that are on my engine.

I bought it just for doing plastic carbs as regular caustic carb dip will detroy plastic carbs. It will eat rubber fuel lines though in short order. Doesn't seem to bother viton needle and seats, but the neoprene ones will swell up a bit in it.

[Joker2]

I have been adding the Sta-bil for ethanol every time I get gas since I got the motor ( last Sep. ) when it was newly rebuilt. I am thinking more about a product for decarboning. I just got a known good compression tester yesterday, I will do that first and see what my results are. I only have about 18 hours on motor, ( 10 hrs of break-in running double oil ) it seems like not enough to have to decarb. I have a 20 minute ride at idling speed each way till I get to open water every time I go out, wondering about how that is for buildup ? trying to get it to run smoother at idle and get more power out of it, only 45-4900 RPM's max 25 MPH on GPS

[Joker2]

Well went out today. Got to boat swap out the fuel / water seperator filter next off to gas dock ( 16 Gal high test ), had a problem threading on my Perko plastic gas cap, I deformed the threads and just forced it on, ( I know I need a metal one )off to go tubing, everything normal, tubing for about 1 hour, through all rpm ranges a little opened up, all fine, then it happened, she started cutting out on me no power, got it started with the fast idle lever a few times, drove a couple of hunded feet it happened again, started it dropped down the fast idle she wouldn't stay running, dumped my water seperator real quick and put it back, looked OK, also right before this happened as I was backing away from the beach slowly, into a slight chop, a little wave came over the transom, ( not sure if this has anything to do with it ) problem started shortly after that happened. Could water have gotten in somehow ?Not sure what to do, Tomorrow I am checking comp. Any chance this could be a fuel pump problem?

[phatdaddy]

so all was good until u ran x number of gallons out of the tank, try seperate fuel system and see if problems follow tank or engine

[Joker2]

Did comp. test this morning with a brand new screw in type tester. Had to do it with the engine cold, I can't start it. I got 120 lbs. on all three starboard side cyl. Had 100 lbs. on all three port side cyl. Also this is the 3rd time I found black buildup on the lower starboard side plug. I just changed the plugs last week, only ran motor about 2 hours since. I will try seperate fuel, I think those numbers were like that since I got boat, I feel yesterday was fuel related, just wanted to check comp. Is there a problem with these comp. numbers ?