Is this engine on its last leg???

[Bobby Powell]

Engine is a '84 90hp IL6. <br />Been very reliable past couple of years. About a three weeks ago the motor was almost impossible to start. I had to put a shot of mixed fuel into the mouth of the cardbs in order to get it to start. After it starts it runs like a champ. Cut it off and let it sit for 20 mins then start it again...no problem. Cut it off again and let it sit for 3 hours and then it's hard to start again.<br /><br />I replaced the Tempo fuel filter/water seperator. Replaced clear inline fuel filter just before the fuel pump. Took it back out and the probelm still exist. <br /><br />Removed the fuel filter/water seperator and retested...still exist. Now I am thinking it may be bad fuel lines but I don't see any air bubbles in the clear inline fuel filter....so I count that out. <br /><br />Now I can now get it started by priming the fuel bulb till it's hard then holding down the push to choke (fuel enrichment system) for about 10 seconds and then reprime the bulb and choke again for another 10 seconds...do this one more time then it starts up after a couple of cranks..sounds like it's flooded for about 5 seconds then idle outs fine. Possible weak fuel pump diaphram??? <br /><br />So now I am thinking it maybe gummed up carbs.<br />I pull the plugs and found number 2 fouled, 3, 4, & 5 look clean with traces of spark, and number one is fouled with itsy bitsy pieces of metal shavings. <br />The shavings were balck as if they were in there when the motor was running...which throws out my buddies thought that the shavings were from the threads of the spark plugs...which the last two full turns were kinda hard to get it out...once breaking free the plug unscrews by hand and then the last 2 full turns requires assistance of a socket wrench. <br /><br />Now I am looking for advice.<br />Should I rebuild carbs and clean out the number one cylnder as good as I can and let her run till the motor really croaks??? <br /><br />Or is this motor now beyond help and ready for the grave yard??? <br />If so it would be a donar motor first for any other sick motors.<br /><br />Problem is...if it's dead then I am out of a motor till winter time. <br />Looking for advice on what to do...and want to hear other past experiences similar to mine...what was the outcome?<br /><br />Thanks in advance....<br /><br />Bobby

 

[BF]

Re: Is this engine on its last leg???

Hi,<br /><br />How about doing a compression test? Sounds like the one cylinder/piston/rings might be damaged. A compression test will tell you. Sometimes if a piston breaks up, hunks of metal get whacked into the spark plug. Maybe it deformed the electrode end of the plug (making it hard to remove).<br /><br />I've never tried it myself, but I'd think a motor running with one dead cylinder probably would not go for long (and would probably leave you paddling).<br /><br />My guess is that it had a clogged carb, and once you got it up and running on the other 5 cylinders the cylinder with the clogged carb (and no fuel/oil) eventually melted down.<br /><br />Depending what the compression test tells you, maybe you can find another "tower of power" for cheap with a good powerhead but a wrecked lower unit and make one good one (?). <br /><br />good luck.<br />Brent

 

[mcginleyc]

Re: Is this engine on its last leg???

Bobby, I agree with the quick diagnosis of BF. I would say that if the motor runs well have that number 2 cylinder bored. Keep in mind that you have to find what originally caused the problem or it will happen again. I would rebuild all carbs after having it bored. This is standard procedure along with replacing fuel lines. To get everything absolutely clear in the carbs soak them as well as rebuild them. Just make sure to remove any spagetti seals, but I don't think those old carbs had any. I guess it all comes down to the $ aspect. Good luck

 

[Greg New Zealand]

Re: Is this engine on its last leg???

Don't write off your motor just yet. You mention that it idles out fine. How is it running at WOT and other throttle ranges?<br /><br />I agree with BF - do a compression test and compare all cylinders. Have you done a de-carb? Carbon build up may be a reason for hard starting and she may just need this all blown out. They run so much better after a clean out. Seafoam is popular over there and it will give your carbs a clean too.<br /><br />Keep posting

 

[Bobby Powell]

Re: Is this engine on its last leg???

Thanks to all that replied. <br /><br />BF, Good Idea...didn't think of doing a compression test.<br /><br />Greg,<br />Motor runs great through the whole throttle range.<br />Although I did a decarb last fall. Probably 20 hours ago.<br /><br />I'll do a compression test and rebuild the carbs.<br /><br />If compression is bad...looks like I'll be buying a motor from iboats.<br /><br />Thanks,<br />Bobby Powell

 

[Clams Canino]

Re: Is this engine on its last leg???

Don't sell it short yet. Test it and decarb yet again. Often times a melting piston will foul the plug and save itself. The inline 6 always requires a bit of throttle and a LOT of choke to start.<br /><br />-W

 

[Greg New Zealand]

Re: Is this engine on its last leg???

Hey Clams - great to see you back on board.

 

[Bobby Powell]

Re: Is this engine on its last leg???

Clams, you have given me hope! <br /><br />Thanks, a bunch...<br />(obviously that's what I wanted to hear) <br /><br />Sometimes the truth hurts but it never hurts to to be hopeful.<br /><br />I let ya'll kow how it goes.<br /><br />Bobby

 

[threecylinder]

Re: Is this engine on its last leg???

Yes, it is done for! Please crate it up and send it to me immediately!<br /><br />Are you sure the pieces were metal? Possibly they were just black pieces of carbon?