Need Help: 85 Merc. 75 hp...probs with stalling when putting in gear

RiverKnight

Cadet
Joined
Apr 20, 2011
Messages
20
I have an 85 Merc. 75 hp , when you first put it in the water runs fine, then after you run say 10 minutes and stop it wants to stall when you go back in gear and apply gas to it.Yesterday I thought to hit the choke while I gave it the gas and it took off. Problem seems to get worse the longer you run. Does anyone have any suggestions as to what is the problem here? I know it's gotta be getting to much air or not enough gas, any help will be greatly appreciated.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,074
Re: Need Help: 85 Merc. 75 hp...probs with stalling when putting in gear

First do a compression/spark test.Then rebuild the fuel pump and clean the carbs.Ethanol is a big problem with older outboards.
It's melting hoses and causing hoses to delaminate and collapse.
Replace all the hoses.Any inline connectors can be sucking air.I just remove them.
What's the rpm's at idle,in gear?Maybe too low.Reset the air screw.J
 

RiverKnight

Cadet
Joined
Apr 20, 2011
Messages
20
Re: Need Help: 85 Merc. 75 hp...probs with stalling when putting in gear

First do a compression/spark test.Then rebuild the fuel pump and clean the carbs.Ethanol is a big problem with older outboards.
It's melting hoses and causing hoses to delaminate and collapse.
Replace all the hoses.Any inline connectors can be sucking air.I just remove them.
What's the rpm's at idle,in gear?Maybe too low.Reset the air screw.J

Got real good compression ,motor idles good , cranks every time can run long as u want as long as u keep some speed just acts up when u stop and restart. I know what u talking about with the ethanol...sorta got fed up trying to figure it out myself so this morning I took it down to the beach to The Marine Service Center, they gonna take a look and see what it is. I know it's gonna cost me there but I'm ready to ride and it's nice weather down here. I'll post what the prob is when they call me back, told em to call before they do the work cause I ain't trying to spend a fortune in this deal.Thanks for your insight to the prob, check back for the update..
 

RiverKnight

Cadet
Joined
Apr 20, 2011
Messages
20
Re: Need Help: 85 Merc. 75 hp...probs with stalling when putting in gear

OK, the Marine Service Center called , they saying its the carbs and the doing a rebuild on the carbs ,should have the boat back Monday
 

RiverKnight

Cadet
Joined
Apr 20, 2011
Messages
20
Re: Need Help: 85 Merc. 75 hp...probs with stalling when putting in gear

well prob solved carbs , springs cap gasket set diaphragn,gasket grand total of 19 bucks oh but the labor was the killer 360 bucks but guess I'm happy boat runs great and I'm back fishing. Actually made it down to Murlles Inlet to the Spring Flounder Tournament it was a great day if you missed it better get on down next year. Anyway good luck and good fishing, if it bogs it's probally the carbs...
 
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