awwwww%%$$#, it got me

[Deerdog]

Hey guys,<br />Im back from the lake and the boat shop. Saturday my 150 Force started acting up. It will cranks up fine and idle like a kitten. Upon take off it boggs down but then quickly picks back up. Then it will do this on and off all the way from 2500 to 5500 rpm. It is kind of a cross between a bog and a dead miss.<br /><br />Anyway, we pulled the plugs and they all look fine (no "steam cleaned" plugs), although the #3 cylinder was a bit more coated than the rest with carbon.<br /><br />Since the boat was recently tuned in May (and ran great after that) we took it back to the shop (our friends run the place). John, the owner and friend, seems to think it may be either a stator or a coil breaking down. My dad seems to think it is fuel related. <br /><br />The tank was full of 93 Octane fuel (it wont run worth a **** on anything else) and the oil was properly mixed.<br /><br />I tend to think it may be a coil breakng down vice anything else. Any opinions would be appreciated. We all do not think it is anything serious but would appreciate any opinions. Im will find out here in a few days for sure.<br /><br />Thanks<br />Deerdog

 

[mikec]

Re: awwwww%%$$#, it got me

Id be very interested in what the outcome is. I have a very simular issue (see post below about 1992 200hp rude missing) I checked all my plugs with a timing light under failing operating load and RPM (w/o falling out of the boat even) and they checked good. Mine is fuel related, i think... Im thinking carb, or starvation, or VRO, or mix of all now...<br /><br />-mikec

 

[kev_79]

Re: awwwww%%$$#, it got me

Tough one! To find out if you have a coil breaking down is going to be hard unless you have somthing to test up to 50000 volts. When they begin to break down, it is tough, but when they go out, that is the easy part. I also would check to spark plug wires. I had a problem with one of mine once, where it had begun to break down, and was grouding against the block, or other plug wires. Some rubber tape with some electrical tape over it will fix this prob. Well, just something to check, hope it helps

 

[JB]

Re: awwwww%%$$#, it got me

I would be interested to know why an engine with the equivalent of a 7:1 compression ratio requires 93 octane fuel. The answer to that will probably point to the answer to your complaint. Remember that octane increasing additives are simply compromises to get gasoline to burn, rather than exploding, under excess pressure and heat. Those same additives create the deposits that destroy 2 stroke engines.<br /><br />Check compression and timing. Most likely suspect is ignition firing way too soon.<br /><br />Red sky at night. . . <br />JB

 

[Deerdog]

Re: awwwww%%$$#, it got me

Thanks for teh replies so far. We did continuity checks on each plug wire and they were all fine. That was one of our first things we checked out once we ruled out air and fuel.<br /><br />As for the hi-test (93 Octane): It is a Force engine which doesnt like the lower grades. The shop recommends an Octane of 92 or better. Also I can tell a difference in the way it performs with lower Octane fuel.<br /><br />The shop can test for coil breakdown as well as the stator, whihc is what I am pretty sure the problem lies. My dad had a boat years ago with a very reliable Chrysler 70 on it. It had a coil breaking down on it and exhibited the same symptoms as my boat did on saturday. will let you all know wht it turned out to be.<br /><br />Deerdog

 

[sony2001]

Re: awwwww%%$$#, it got me

Sounds like an intermittant CD unit [switchbox].

 

[ODDD1]

Re: awwwww%%$$#, it got me

Deerdog, problems like what you describe are usually fuel related... water in the fuel tank? water in the carbs? last time the fuel pump diaphram was changed? float bowls have green goo in them?<br /> All you guys remember a fuel prob will generally give a 'soft' miss/bog , an ignition prob will give a SHARP hard miss.....

 

[mikec]

Re: awwwww%%$$#, it got me

I fixed mine tonight with simular symptoms ( An Evinrude though, 200hp, 1992) It ended up being carb screws and bolts not being tourqued quite enough, seems like the machine was sucking air ( fuel starvation ) within the RPM power band.<br /><br />Good Luck!

 

[chads15]

Re: awwwww%%$$#, it got me

deerdog,<br /> <br />i have that force 150 thatr was giving me thoes overheating problems. had the same problem with mine 6 years ago. i am running 87-89 octane in mine and it does the EXACT oppisite too. if i put anything higher in it, it dont run for crap. but anyway, i had the same problem and it was a fuel problem. some moisture in the bowl was giving me fits. so drop the bowls and clean them and see what happens.<br /><br />Chad