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compression question 3cylinders at 140 and one at 125?

May be something stupid like a stuck ring, may be scoring. It should run fine like that though. I'd check for obvious things and would just run it and keep an eye on it.

You may be able to peer in through the spark plug hole and find some clues but given it's an inline engine there's no way I know of to inspect the cylinder without tearing it down. Does the plug look any different on that one? Has it ever been rebuilt before?

Jon
 
Which triple is this, and which cylinder is 125? If it's one of the earlier ones, and it's the top, you're in trouble.

Jeff
 
Yeah they tested it 3-4 times . And the bottom one is the 125 .and it looked and felt a little wet compared to the other ones . To my knowledge is has not been rebuilt . The guy at the shop said I was taking a risk to get a carb rebuild bc he's not sure if that would fix my problem . My pronlem is when I give throttle , the boat wants to die and it feels like it's not gwtting enough fuel
 
sevensixoh said:
Yeah they tested it 3-4 times . And the bottom one is the 125 .and it looked and felt a little wet compared to the other ones . To my knowledge is has not been rebuilt . The guy at the shop said I was taking a risk to get a carb rebuild bc he's not sure if that would fix my problem . My pronlem is when I give throttle , the boat wants to die and it feels like it's not gwtting enough fuel
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Assuming it's an older engine you don't want to pay to rebuild, the worse scenario by running it with a problem is you make it worse and eventually that cylinder scrapes itself worse.. There's no other way to even investigate a compression issue with an inline engine other than tearing it down, of which the labor is probably 50-80% of the cost involved during a rebuild.

In my humble opinion, given it's a borderline difference as mentioned, the engine should be able to run OK. Even with an obviously bad cylinder some engines run just fine, the others just carry it. Bogging is typically a carb problem, most likely your issue is simple clogged carbs.

When you need to pay someone to do everything though the cost of a carb rebuild goes from ~$100 in parts and some of your own time, to something closer to $400 (I figure they bill 2.5 hours shop time at $100 and parts at $150).

It's probably worth the risk to have them rebuild carbs given your other option is a new outboard for ~9K (assume it's a 70HP engine?).. But if you are really not the type to be doing any such work on your own, getting something new with a warranty may be your best bet in the long run. Repairs are very expensive and they really add up if your only option is the dealership, so you deal with both downtime in the boat and the cost, it often works out better just to finance something new.

Jon
 
Disconnect the fuel line and run the carbs until dry. Reconnect the fuel line and disconnect it at the tank then stick it into a can of SeaFoam or equal and fill the carbs w/it using the squeeze bub primer. Keep the engine upright and let the SeaFoam soak for 24 hrs. Squeeze the bulb until firm after 12 hrs. in case some liquid evaporates. Reconnect the fuel line and start it on a hose and run it at 1200 RPM until it stops smoking.
 
There's no other way to even investigate a compression issue with an inline engine other than tearing it down
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If its the crossflow triple you can remove the transfer and exhaust covers and inspect the cylinders wall and rings..
 
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