Crankcase seal

jtcarter

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A question for one of the old wise men on this board..... 1995 175 intruder motor. Is there anyway possible to check for a crankcase seal leak in this motor? If the crankcase seal was leaking, should i be getting water into a cylinder somewhere? Showing up on a plug?
 

Dhadley

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Feb 4, 2001
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Re: Crankcase seal

What is your motor doing or not doing? Are you getting water showing up on a plug? If so, which one?
 

jtcarter

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Re: Crankcase seal

What is your motor doing or not doing? Are you getting water showing up on a plug? If so, which one?
No water showing up on any plugs. I'm just having to run my air idle screws out about twice what spec calls for... for it to idle properly. I'm trying to find a reason for it. Air leak somewhere sounds about right. I'm pretty confident its not behind the oms, i've been watching for air bubbles and seem to have that problem resolved. You can set this thing at factory specs on the air screws and it won't run longer than a minute, spitting and jerking and coughing. Only when you run them out way past spec do you achieve a smooth idle with no lean pop or obvious miss. Carbs have fresh kits, i've even pulled them off and took them to a omc guy and we tore it down and went through it again, just to make sure i did it right. The old motor just doesn't want to run at low speed after you make a initial run up lake. Seems like the longer you let it set the worse the condition is. It bogs or stalls when you try to get up on plain. It also has either a miss or lean sneeze at idle after its sat for awhile. Dhadley, i've got a few post from last year on this board, just advance search and you'll see what i've went through with this thing. I seem to be able to get it to a point with the air screws that if i let it sit for a minute it finally takes off. Just kind of odd i'd have to run those screws out to that extreme to get it to run. My service book says 3 to 4 turns out. I've got them at 8 and thats where it likes to idle, weird huh.
 

Dhadley

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Feb 4, 2001
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16,978
Re: Crankcase seal

We've seen a lot of motors that the motor runs best at 8 or 9 turns out. Some motors call for that much, some don't. If you think you might have an air leak check the plates on the side of the carb body. That's an often overlooked source for an air leak.
 

jtcarter

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Re: Crankcase seal

I'm taking it to the water right now. I'll check back n later with a report, hopefully a good one.
 

jtcarter

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Re: Crankcase seal

Well i think i'm on to something here. I definitely runs better with those idle screws at 8 turns. It didn't lean sneeze but one time and thats when i was loading it on the trailer. It got on plane everytime and never sneezed but once. I'm thinking maybe another 1/4 to 1/2 turn out and i might be done, hopefully. The only thing is it wasn't hot today and the water temp had cooled off from the big rains we've had. I'll know for sure if i'm done with it, when it heats up again. That is more than likely the problem though as it really ran pretty much flawlessly everytime i started it and ran to my next spot, i've been sqeezing the bulb before i start it everytime and i think i'll continue to do so. When this thing runs right, you couldn't ask for better performance from a outboard. I guess thats why i haven't completely given up on it yet. We'll see, i've thought i had this thing fixed before and it let me down. The real test will be when we get some hotter weather. May start fishing early in the day to avoid being in the heat though, it really drains you bad, screws up your whole day.
 

Dhadley

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16,978
Re: Crankcase seal

OK, now a couple of things to look at. Make sure you're running fresh 87 octane and the right Champion plugs.
 

jtcarter

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Apr 26, 2008
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226
Re: Crankcase seal

OK, now a couple of things to look at. Make sure you're running fresh 87 octane and the right Champion plugs.
Its fresh feul. I buy only real gas, the horror story's i've heard about crapanol scares me. QL78YC is the plug i'm running. My service book calls for QL82YC. I think these plugs cross reference though. At some point OMC recommended running the QL78YC on all loopers over 40hp, 94 and later models if i remember correctly.
 
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