1975-115hp 4cyl starting and running problems

[firstboat25]

Hope you guys can help me with this<br /><br />What boat does is that when you go to start her up all you do is crank and crank she will try to start but its like there is no fuel reaching carbs<br />I rebuilt them thinking that was there problem put back on and same result nothing.So I took them back off and checked the float needle and saw that it was sticking so I put a drop of oil in and they moved freely.Put carbs back on still same result nothing<br /> So I mixed some gas and oil in a spray bottle and would spray the carbs and get the engine to start up,she would run but die so I would keep spraying the carbs to keep her runnin all of a sudden I noticed that she would stay runnin longer and longer then all of a sudden she would idle pretty good and when she would stall just turn the key and she fired back up thought I was finally making progress<br />WELL I PUT IN GEAR TO CHECK THE LOWER END GAVE HER GAS WAS RUNNING PRETTY GOOD THEN SHE STALLED AND BACK TO SAME PROBLEM <br />DOES NOT WANT TO START WITHOUT THE SPRAY IN CARBS<br />AND WONT STAY RUNNIN EITHER PLUS SHE IS GIVING SOME BACKFIRE <br />Im tired of killin my batteries trying to start this and fix this anyone please help

 

[KYHunter]

Re: 1975-115hp 4cyl starting and running problems

Have you checked your fuel supply , ie: lines from tank, bulb, pump, filters, etc. Thats where I would start , the simple things first. If your sure you have good fuel supply getting to carbs then spark test , compression test, it seems though that if she'll run when you spray that its in the fuel system . I'm no expert but the fuel system is pretty simple on the older motors I have a '78 115. Make sure you check your vent line to tank ,every part of it , the check valve (fitting)where feed line to carbs connects at tank, the line and the through hull fitting. I'm assuming you have permanent tank if not disregard last statement.<br /> Good-Luck,<br /> KYHunter

 

[firstboat25]

Re: 1975-115hp 4cyl starting and running problems

I do have a permenant tank I even went as far as takin it out of the boat and just have it sitting on the ground. I agree that it does seem that it is in the fuel system but I just cant find it everything looks ok

 

[KYHunter]

Re: 1975-115hp 4cyl starting and running problems

Hook motor up to a temporary tank , make sure its vented and if it runs you know its somthing in your fuel supply . Check the little ball bearing, and spring , check valve fitting I mentioned above, I threw the spring and ball in the lake . Mine was sticking along with a bug in vent line . <br /> Good-Luck,<br /> KYHunter

 

[firstboat25]

Re: 1975-115hp 4cyl starting and running problems

I was just reading could the fuel/oil mixture cause this problem ?

 

[Pony]

Re: 1975-115hp 4cyl starting and running problems

Like KY says im betting its in the fuel system as well....had a similar problem with 71'. Ended up being a clog in the fuel lines before the carberators. I replaced them with the see through kind. While you are at it you may want to check the fuel pump out as well, to see if your diaphram is strong enough to push the fuel to the carbs. just my 2 cents.

 

[PDS]

Re: 1975-115hp 4cyl starting and running problems

That bit about the needle valve sticking bothers me. If it sticks once who's to say it won't stick again. Another place to check is the quick disconnect (fuel) at the engine front. If there is any small leak fuel pump will suck air in. Good luck!

 

[Solittle]

Re: 1975-115hp 4cyl starting and running problems

Describe in some detail how you rebuilt the carbs. My bet is that there is still some crud somewhere in the carbs.

 

[firstboat25]

Re: 1975-115hp 4cyl starting and running problems

HI solittle<br /><br />the kits I bought was to me pretty basic I replaced the needle and seat and the orifes gasket and drain bowl gaskets along with float bowl gasket <br />I soaked the carb and blew out everything with my compressor<br />I also posted an update if you could check it out I would appreciate it