Tower of Power with stalling when put into gear.

[Fed up]

I have a 79 115 Merc, recently put this motor on this boat and it was running when I swapped over. I was having some issues before swapping, when on the water you would have to hit the primer bulb when you first started to throttle up, then she would build power at take off and run great. Now after swapping the motor to a different boat I am having similar issues, I have broken down the carbs and cleaned them with cleaner and compressed air. I did not replace anything other than the fuel lines at this point. The boat got all new fuel lines and bulbs, new filters. Once you get the motor in gear and hit the primer bulb to get her going she runs like a champ, so where do I need to go from here?

Some times it will idle all day long, other times she will fire up and then die. go through this routine for a few minutes then she will fire and run like a champ, until you let it sit for a few minutes then we are back to where we started again.

 

[merc850]

Re: Tower of Power with stalling when put into gear.

If you have these carbs

there is a filter in the top that can get plugged and cause that kind of problem.

 

[Fed up]

Re: Tower of Power with stalling when put into gear.

Thanks for the tip on the filter. That seemed to be the issue, I think. After some tuning on the water I got her running decent when another issue seemed to come out.

It starts good but the idle is a bit rough and high, when you give it full thottle it seems to come out of the hole really strong but I can only get the rpm up to 5200 while at full throttle. It will get to 4900 then you trim up while on plane and it will go to 5200. Do I need to look at adjusting something to get is up another 600 rpm?

also on a side note, I removed the hydrofoil from the foot. It drives smoother while on plane but it takes a bit more time to plane out.

I should mention that the motor is on a 1989 15' Champion bass boat.

 

[redjmp]

Re: Tower of Power with stalling when put into gear.

Sounds like you need to do a link and sync.
http://forums.iboats.com/showthread.php?t=128495&highlight=clams+canino

 

[Fed up]

Re: Tower of Power with stalling when put into gear.

I will give that a try and let you guys know how it turns out.

 

[RiverKnight]

Re: Tower of Power with stalling when put into gear.

It's the carbs , just had the same prob ,, new kits installe , diaphragm , gaskets,spring, etc. She's back on the water, one thing I can tell you leave the small time repair shops behind else you gonna get screwed less you get lucky....lol....not my experience..took mine to the MARINE SERVICE CENTER at Cherry Grove , paid alittle more but it's right now and the service was the best I ever had , liove and learn again.. good luck.. could also be the fuel pump might be something to look at

 

[sourbsted]

Re: Tower of Power with stalling when put into gear.

Make shore your timing belt is in good shape. Mine was like that before the bastard broke! It would idle out of the water but once you hit the water it stall.. Had to go fast idle then quickly back it off then hit the forward lever.. A weak fuel pump can be a culprit too..

 

[quantumman29]

Re: Tower of Power with stalling when put into gear.

my tower of power was acting the same way,my problem was it was overheating,I needed new water pump,impeller,and there was a lot of bits and peices of rubber fragments in the cam shafts and carbs,had it totally cleaned out and she runs like a champ now,i have a little hesitation during take off but it quickly goes away,
mike

 

[Fed up]

Re: Tower of Power with stalling when put into gear.

Ok I think that I have got the problem solved, well at least something else eliminated from the equation.

I did the link and sync, the carbs were off a bit, so got it all buttoned back up and hit the water for some final tuning. Ran like a champ but still was not getting all the RPM that I needed. So back home we go. Pulled the carbs once again just to double check everything, then the link and sync again (at this point I can about do it in my sleep). So a week goes by before I am able to hit the water once again, back on the water it is having the same issues, but this time a new symptom shows up, you have to hit the primer bulb to get off idle other wise it will die.
What I noticed (once I pulled the cover off) was that the primer ball would get firm, but not rock hard and would pour gas out of the carbs.

So on my way home from the water I stopped by my mechanics shop (Performance Marine) these guys have awesome customer service and know their mercs inside and out, and told him I needed a fuel pump rebuild kit, and plugs. He asked what the problems were, so I told him everything.

He said lets take a look, so we pulled the fuel pump in the parking lot and he spotted one of the check valves that was not looking quite right, so we have a kit on order ( next day delivery) and he proceeded to inform me that most of my problems very well should be the fuel pump.

It would explain the rough idle, the flooding, and the bog that I am getting.
So The parts should be in tomorrow morning, I am going to do what I need to do and see if it changes anything.

On a side note, when you have two of the same motors and could swear that you did one thing to one motor, it could be very possible that you did it to the second motor and not the first. This is my case here, I rebuilt the fuel pump on my Mariner but not on the merc once I switched it over to the new boat.

 

[bktheking]

Re: Tower of Power with stalling when put into gear.

My motor has twin pumps, does yours?

 

[Fed up]

Re: Tower of Power with stalling when put into gear.

No, just a single pump on the motor.

 

[bktheking]

Re: Tower of Power with stalling when put into gear.

Huh, mines got 2 and a spot for a 3rd but it's not drilled in the block.

 

[Chris1956]

Re: Tower of Power with stalling when put into gear.

Fed - Your problem of fuel pouring out of the carbs will not be fixed by rebuilding the fuel pump. You have a stuck float, bad float or bad inlet needle or seat. They stick a lot and can unstick themselves, so it may get better on it's own. Don't credit the fuel pump rebuild with the fix, however. The rough idle is caused by a misadjusted carb idle mixture or the flooding as well. Again it ain't the fuel pump.

BK, the early inline 6 Mercs had the two fuel pumps mounted on the transfer covers. The later ones were mounted on the starboard side of the lower cowling, and had pulse hoses connect them to the transfer covers.