need advice please- engine shot?

tnvolsdj

Recruit
Joined
Jul 3, 2004
Messages
4
I am not very mechanical so please be kind. Boat was running fine then died. Was able to restart, but could barely go over idle without enging quitting- "limped" back to dock like that. Ran compression test both cold and warm. I read 2 different instructions and got the following results:<br /> cold warm<br />top 129 123<br />middle 139 129 <br />bottom 129 123<br /><br />I took off the head and everything was dirty, but I couldnt really see any damage or anything. I am not sure, but wouldnt damage be obvious?<br /><br />Also I noticed a little fluid (gas mix) collected in the bottom of the carb intake.<br /><br />85 Force 85 HP<br /><br />so is the engine ( and me) screwed? mechanic said if compression was bad I was looking at 2K and he didnt even want to work on a POS Force. I have the manuals, but I am not sure I could do it myself. Also, if buying a replacement engine, does this one have 20 inch shaft??
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: need advice please- engine shot?

Hi, Davod.<br /><br />Welcome to iboats. :) <br /><br />No, your engine is not terminal. The compression numbers are fine.<br /><br />From your description it sounds like you have lost fuel flow or lost spark to one or more cylinders.<br /><br />Bad idea to pull the head. You will need a new head gasket.<br /><br />Put her back together and try squirting some fuel premix into the carbs while running. Does it pick up speed? That would suggest a gummed up carb.<br /><br />Does it have spark to each cylinder? You may have lost spark on one or more.<br /><br />Is the throttle plate opening fully on all carbs?<br /><br />Let us know what you find.<br /><br />Good luck. :)
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,797
Re: need advice please- engine shot?

Ditto JB.<br />Your compression readings look great for a motor of that age.
 

tnvolsdj

Recruit
Joined
Jul 3, 2004
Messages
4
Re: need advice please- engine shot?

Some good new- thank you! Is it possible that I am not doing compression test correctly, because I took it to mechanic and he said once cyl was bad? I did it myself because I want to make this a whole learning experience and sometimes Im not all that trusting. Surely, the mechanic would not be trying to rip me off? <br /><br />As for the spark - before I took off head, I had one of those little tools that lights up if spark is going. I got a shock using it just placing it on the wire for the middle cyl. It seemed like the plug wires came off pretty easily. Upon inspecting the plugs I found the caps to them were loose. These plugs were installed last year.<br /><br />Since I have the head off, should I clean all the parts ( the insides of the cyldrs too)? What to use? What not to do?<br /><br />You guys are really great to help with the info
 

tnvolsdj

Recruit
Joined
Jul 3, 2004
Messages
4
Re: need advice please- engine shot?

I got the head gasket and put the head back on. Took it out today and it worked great for a little while, then stalled. Cranked right back up but wouldnt go very fast without dying. I thought -thank God I stayed fairly close to dock! I was completely disgusted. <br /><br />I pulled the boat out of the water and was preparing for the drive home, when I took off the engine cover. A spark plug wire had fallen completely off the spark plug on the top cyl. I took the boat home and compared the old plugs with these newer ones that had been installed last year. The new ones were Napa Autolite the old were Champions. I stuck the old plug in the wire and it appears to have a thicker body and the plug stays in.<br /><br />Looks like I may have found my problem!!!!
 

CoachHolland

Petty Officer 2nd Class
Joined
Apr 20, 2004
Messages
165
Re: need advice please- engine shot?

I think your mechanic told you a bad cylinder and two grand just because he didn't want to work on the engine.<br /><br />Glad to hear that it was a cheap fix. I wasn't aware that Autolite made gapless plugs for this motor. The champions are gapless, right?
 

tnvolsdj

Recruit
Joined
Jul 3, 2004
Messages
4
Re: need advice please- engine shot?

The autolites were not gapless. There old champions were not gapless either L77JC4. Is gapless better?
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: need advice please- engine shot?

Merc calls out a UL18V plug for your motor. This plug is not gapless.
 
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