110 Hp Mercury 1966-67 outboard fuel leak

[allenprimo913]

hi guys,

i finally got my motor running after replacing the plugs and points and tested it on the water yesterday. it idles good out of the water and rough and dies in the water everytime i put it to gears(forward or reverse). i wanna see it run so i increased the idle speed just to get it running. at first it runs ok but rough then hesitate at WOT speed at aprox. 10-15mph. it doesnt seem fast enough for a 110hp. i put 6 gal. of gas and cruised about 3 miles out. While cruising i noticed a gas smell but i dont see any leaks visible outside, took cover off and i dont see any fuel leaking anywhere, the carbs, the fuel lines and the gas tank. because if there is i should be seing fuel spill inside my garage.

so i turned around and BOOM!! motor stop running completely. i pumped the primer and all i feel is air and no gas , my gas tank went empty that quick.
as i got the boat out i saw fuel coming out from the back of the back of the propeller. i dont know where it could be leaking from.

i dont notice the fuel leak if i start it at home at low speed but i can smell and see that the water coming out from the lower unit has smell and mix of gas but where could it be leaking. why is the gas coming out from the propeller and mixed with the water ? so i assumed it leaked all my gas more on high speed. does the fuel pump has something to do with this leak.

thanks for the help guys, i really need response , i like the boat and i plan to take my family this summer but cant do without gas.



i forgot to mention, i have finally got my service manual but i dont see any exploded view of the fuel pump . it has 2 fuel pumps with hoses going to the top carb and lower carb and while running at home i dont see any fuel leaks visible so im not sure where the fuel leaks coming from.

thanks again

 

[Laddies]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

That sounds like a bad fuel pump diaphragm

 

[allenprimo913]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

hi laddies,

you are absolutely right, i disassembled the bottom fuel pump and the diapram is busted and have some water build up in it

i took the top fuel pump too and same thing , no wonder my six gal. gas went only for 3 miles.

where can i order this 1966 parts, i looked at iboats and it says mallory or sierra parts but dont know which one.

how would i know the right part?

i assumed my serial # is 1878825, is this a valid serial number for 1966-67?

thanks again

 

[Laddies]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

The Sierra number is 18-7804, can be purchased thru NAPA, Prime Line parts at most auto stores. You should be able to type it in search at the iboats store, their parts section lacks many numbers as they tend to sell mostly fast moving items I believe.

 

[Yepblaze]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

I would think most of those diaphrams would still be available from Mercury.

I usually opt for the OEM check valve kits, they come with the diaphram and gasket.

Just pay attention when you change them out. To remove all old gasket material, and note inlet/outlet orientation.

 

[allenprimo913]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

i called west marine here in sacramento, california and they have to order it as they dont stock it no more.bucks outboards also has to order and finally one in rancho cordova ,prescision marine has it and i will pick it up in the morning.i checked the price here in iboats plus shipping will cost me at least $11 and at rancho its only $5.75 takes me 20 mins.

hopefully that will fix the rough idle too as soon i replace the fuel diapram

tnks guys for quick response.

 

[allenprimo913]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

its me again, finally i got the kit for the fuel pump and i installed it, at first it sounds very good better than before and i dont see any leaks at all, it ran for few minutes then died and hard to start, the primer is hard and i know theres fuel going in the carbs, i checked the spark on all plugs and they all there but its having hard time starting.

it was running before even the diagphram is busted now that i fixed and replaced the diagphram how come its hard to start. itn seems its out of timing
even if i close the choke still hesitate to start.

should i go check the timing ? even if i didnt touch it before, the only thing i messed with is the idle speed screw of the 3 carbs.

what else could have been damaged when the diagphram was busted, i notice some gunks or gogoms, like muddy black jelly coming out from the place where you put the earmuffs when i was done with it. i had to stop and no luck to get it running because its getting dark.

i need inputs from the expert: if where to start after i replaced the diagphram.

thnks guys

 

[Laddies]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

I think that with the diaphrams leaking the engine had fuel in the crankcase the minute it turned it fired the fuel. Now it must pull it from the carbs, First those engines must have a starting battery not a deep charge as they require a lot of amps to start but I think you may find someone before you got the engine has leaned the carbs down to get it to idle as the diaphrams started to leak to make it idle, thats quite a common problem.

 

[allenprimo913]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

thanks fleet but i didnt quite understand what you mean, do i have to rebuild the carbs or just keep trying starting ?whats the procedure on how to adjust idle mixture speed, i screwed them all the way in till it stop and backoff 2 turns, tried 2 1/4 , 2 1/2 then 3 turns, i had luck most of the time on 2 turns, seem to idle pretty much even but after i replaced the diagphram none yet.
either i m flooding the carbs or timing is off?

does my battery needs charge, does it has to spin faster to get it started? i have another spare and it does the same thing. maybe i have to buy a new fully charged one.

how about those jelly black gummy stuff that came off the bottom are those normal? i was thingking those are the residue of gas/water mix when my diagphram was busted build up.

 

[Laddies]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

If you have not tinkered with the timing or sycronization they should be fine. I think that now it'd running rich, set the carbs at 2 turns and adjust them in the water in gear, if all else fails in the adjustment the carbs will probably have to be cleaned.

 

[allenprimo913]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

thansk laddies

im working on it right now and i noticed the plugs are wet, is that mean im running it rich?

if its too rich , whic way should i go for the adjustments? clockwise or counter clockwise?

i know if i go clockwise the rpm goes high, am i right? is this mean more gas consumed or less?

rich or lean? can you elaborate on this?

thnks

ill wait for your response then i will try it again

 

[Laddies]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

In or clockwise leans the mixture and yes at idle it will use less fuel but thats not the purpose of it, it is to smooth out the idle, if it gains to many RPMs you will need to slow the idle speed down. It is common for surface gap plugs to idle a little wet so that dosn't really tell much.

 

[allenprimo913]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

im trying to start it but it hesitate to start primer is good but i dont see fuel goes or comes out of the carbs which is good, but if i put the gear or lever all the way forward , shouldnt i see fuel squirt on the carbs?

so i probably running it rich or lean then because it feels like im flooding the carbs,

im confused but im still trying so i will try bring the carb idle out conuterclockwise.

tnhks

 

[rtpassini]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

is your spark good? pull your plugs to make sure they are okay after all its been through. you sure you put the pump together right?

 

[allenprimo913]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

okay ,

i finally got it to idle, like i said all sparks good on all plugs.

for some reason, maybe i mean maybe the guy i bought it from which i can locate him no more dicked with it. reason why he sold it to me cheap.

here are some stuff i have to adjust to get it running .

the lever that connects to the distributor was messed up, the throttle cable not adjusted right and the lever cable for forward reverse misaligned.

if i hold the lever advance it a lil bit it runs fine and idle so the reason i adjusted it, now i can control the idle, i have to turn the idle mixture screw to about 4 turns, i dont know and not sure if that is too rich or lean not unless somebody will tell me. but this is what its running right now, i have to bring it to the river to adjust it right when it shift to gears.

with this setup , it hums pretty strong and good not before there was a leak on the diagphram. and it sounds different from before, i think it should sounds like this than before like meaner and stronger now. i can prove that when i bring it to the river.

thasnks guys for the input. gotta go eat..wife's bitching and getting jealous on the boat...

 

[Laddies]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

The fact that the idle jets need to be a couple extra turns open make me think that the carbs are dirty. if it's just the idle passages the worst it will do is, as the they clean up with running you may have to readjust the idle mixture, but if it acts lean at higher speeds don't hope for the best and try to run it as a lean high speed can damage a piston so take the time and clean the carbs.

 

[allenprimo913]

Re: 110 Hp Mercury 1966-67 outboard fuel leak

ok i will do that as soon the carbs kits i ordered from iboats will arrive on tuesday. the weather is not good today anyway so i will just wait.

thnks for your quick response.