1986 135hp Merc Oil Injection

"Hi, I have a 1986 135hp merc

"Hi, I have a 1986 135hp merc that won't idle. Runs strong in all other throddle postions. when I bought it the owner told me he had removed the oil injection system and that I would have to mix the oil in the gas my self. My question is..... could anything that was disconnected from the engine for the oil injection system be causing this idle problem like maybe creating a vacum leak from something that may need capping off or hooked up a different way.... anything that would cause a idle problem ? Thanks for your time and help
Scotty"

"Scotty, with the oil system r

"Scotty, with the oil system removed the only thing that would be "capped" would be the oil feed to the fuel pump.

I don't have a manual for your model year and Merc had a few slightly different designs as to where they fed the oil to the pump, however, if the "cap" is defective at all I would expect that you would have some gas spraying in the vacinity of your fuel pump.

Normally, I would suspect a bad idle (with all else being ok) to be a clogged low speed jet (or jets) in one or more of the carbs..."

"Graham, I'll check these

"Graham, I'll check these things . I think it's time to go through the carbs and get that monkey off my back. Thanks for your help
Scotty"

"There is a service bullitin o

"There is a service bullitin on those engines that pertains to rough idle and excessive smoke. There are bleed restrictors that you can get at a merc parts dealer. They need to be installed in the bleed lines running from the intake to the cyl. there are 5 or 6 lines depending on model. Check with your dealer but I think they are installed about a half inch from the cyls. this might help a little. You should also have your dealer check other service bullitins, just give them your serial number and model."

"Hi Kevin, I did have a defect

"Hi Kevin, I did have a defective cap that caps a 5\16 hose size nipple on the bottom right side of the power head about middle way bottom right. It had a hose with a screw shoved in it with a clamp so tight it cut the hose and broke in half. I ran the engine with the hood off and seen gas spraying out of this fitting. When I block it off it seems to run alittle better. It evens seems like it wants to idle but I ran it with the water hose hooked up I don't know if it will make a difference if I put the boat overboard. If I just block that fitting off will that cause too much gas in the engine and cause the engine to run rich and then in the long run make it burn more gas ? Should I try to return it some where ?Thanks for your time and help
Scotty"

"I'm not sure what fitting

"I'm not sure what fitting this is without seeing it, but it doesn't sound stock. I would recommend having it looked at. If it is a fuel return your engine would definently have idle problems."

"Hi Kevin, This fitting is sto

"Hi Kevin, This fitting is stock I think I found it in the manual and their is a arrow pointing to it and it says crankcase pressure with one way check value. The manual shows air pressure comming out and is a hose that comes off ths fittin that is suppose to go to the oil tank but the tank is gone and this fitting is capped off. when I run the engine without it capped it blows a spray of gas out when it's running. thanks for your time and help
Scotty"