merc 115 won't take fuel , please look!!!!!!!

[penguin]

can someone put some light on this. I have a 1972 merc 115 with about 70 hours on it, fresh water only. last year it ran pretty good but, had an idle problem ...no big deal, so this year it won't start . so I get the manual ( clymer ) and this is what was done....CARBS REBULIT LIKE NEW, NEW FUEL PUMPS,= still no start. NEW GAS TANK/FUEL LINE AND BULB, and it stays rock hard when you prime. = still no start. COMP# #1 125, #2 123, #3 130, #4 125, #5 124, #6 122, PLUGS ARE NEW AND SPARK IS VERY STRONG. so now I think it's the REEDS, so the powerhead comes off with the help of a 12-pack to cool me down . On a stand I check the reeds with the feeler gauge and it does not exceed 0.020 in,. so I RESEALED THE CRANKCASE WITH NEW END SEALS/BEARINGS, GASKETS AND ALL........ THIS THING IS LIKE NEW NOW, AND IT HAS TO RUN, RIGHT? WRONG!... SO HERE IT IS... TIMMING IS GOOD, SPARK IS GOOD, CHOKE IS GOOD, FUEL IS IN THE BOWLS AND WILL NOT DRAW INTO THE ENGINE I NEED THE MERC MASTER ARE YOU OUT THERE? ...THANKS DAVE

 

[eurolarva]

Re: merc 115 won't take fuel , please look!!!!!!!

Did you try spraying gas oil mix into the carbs and see if it will fire that way? Do plugs smell like gas?

 

[penguin]

Re: merc 115 won't take fuel , please look!!!!!!!

yes , and it will sputter a bit until it's gone. I have pulled a few plugs also and squrted some mixture in there, and does the same, sputter-run-sputter-die. the plugs..just a little fuel, not enough to start.

 

[Chris1956]

Re: merc 115 won't take fuel , please look!!!!!!!

davette, It sounds like your carb's idle passages are clogged, or the low speed screws are set wrong. Also, these motors take a lot of choke to get them to start. Spray some fuel into the carbs, close the choke and crank it. If it still doesn't run make sure there is no water in the cylinders and give the idle passages a blast of gumout, reset the idle screws and try it again. The idle passages have a connection to the large (1/16") hole in front of the "butterfly" and three much smaller holes in the throat behind the butterfly. Make sure all are clear.

 

[JB]

Re: merc 115 won't take fuel , please look!!!!!!!

F.A.Q.

 

[penguin]

Re: merc 115 won't take fuel , please look!!!!!!!

I checked them 2 times and they are clear, as for the idle, it also is correct.... It should run... keep askin me all that you can think of,and I will check again. thanks. dave

 

[DHPMARINE]

Re: merc 115 won't take fuel , please look!!!!!!!

Are the choke plates closing fully?<br />DHP

 

[penguin]

Re: merc 115 won't take fuel , please look!!!!!!!

yes they are, and they work well... thanks

 

[Chris1956]

Re: merc 115 won't take fuel , please look!!!!!!!

OK davette, it would appear we need to find the obscure issue, since the obvious issues seem to be non-problems. <br /><br />Is it possible that there is an air leak into the crankcase? This would make the mixture too lean to run. Check the transfer cover gaskets, carb base gaskets, crankcase bolt torque, look for cracks/holes in the crankcase cover. Are the main bearing bolts installed? Are the balance hoses leaking air?<br /><br />Other thoughts: <br /><br />I had a bunch of trouble with fouled plugs while trying to use a 25::1 breakin mixture on my '77 150 Merc. Those gapless plugs #$%&, IMO. Is it possible yours are fouled? You can try gap plugs of the correct size to see if it helps. (Change them back to gapless if it runs however)<br /><br />Does fuel drain out of the main jet when the brass jet cover bolt is removed? Is the main jet clean?<br />There is a fuel passage from the carb bowl to behind the main jet. If this is clogged, no fuel will get into the motor. This is a fairly large passage however, and should be the last to clog.<br />Is the "idle restrictor tube" (AKA idle jet) clean?<br /><br />That is all the possible, yet unusual stuff I can thing of at this moment. Give us an update, if you make progress, or find out something new.

 

[penguin]

Re: merc 115 won't take fuel , please look!!!!!!!

thanks chris, I will check it out. you know I do not miss much , but you had pointed out a couple of things I may not have looked at #1 THE BALANCE HOSES, and the PLUGS, they are new ,but a different brand-champion,vs ngk. anyways....I will go over it again incl; the carbs. I will keep you posted...wish me luck, and thanks to all of you.

 

[andrewkafp]

Re: merc 115 won't take fuel , please look!!!!!!!

Originally posted by JB:<br /> F.A.Q.

Try JB's process of elimination as suggested to isolate the cause.<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=forum;f=36

 

[penguin]

Re: merc 115 won't take fuel , please look!!!!!!!

I have never seen anything like this before, I have done everything but buy a new motor, and i still see these motors on the water running great. I am....stuck, any other things I may try before i pull this motor off my boat. thanks

 

[m_bickle]

Re: merc 115 won't take fuel , please look!!!!!!!

Since you have tried the obvious you may want to look at the ignition sys. If the plugs are wet? Are you firing in the right order? You may have the fuel but not the spark at the right time. Just a thought.