Need some help with a 1977 Mercury 1150 Inline 6!

[Coach Doss]

Hello All! Thanks for the help in advance!

I have recently become the owner of a 77 merc 1150. I need some help getting the thing running. I can get it to crank and run with water muffs on and I get it to the water and it wont start. The only way I can get it to cold start is by adding some gas/oil mix into the cylinder through the spark plug hole. After I get it started it runs fine. After it runs a while I can cut it off and it will start up like a new one.

My problem comes when it sits for about 10 mins. then the only way I can get it started is to add the fuel/oil through the plug holes.

Can someone give me some ideas on what the problem is and how to correct the situation. I am new to boating and would be glad to take any advice.

Thanks!
Coach Doss

 

[Coach Doss]

Re: Need some help with a 1977 Mercury 1150 Inline 6!

Bump.

 

[emilime75]

Re: Need some help with a 1977 Mercury 1150 Inline 6!

I have the same motor. I assume you have a 2 lever control box with it? If so, are you lifting the cold start lever when trying to start it? Mine requires I lift the lever to fully open, fire it up, back the lever down to half way and let it idle high for a minute or 2. At that point I can drop the cold start lever all the way and the boat will idle well and run fine.

To tell you the truth I am not even sure if this is the way it's supposed to be as this is my very first boat ever and I've only had it for 2 weeks. Someone more knowledgable might chime in with a better solution, but this one works for me. Hope that helps.

 

[dlplost]

Re: Need some help with a 1977 Mercury 1150 Inline 6!

pull the cowl off and verify the choke IS working. We had a 90 that did that, found out the choke only partially closed sometimes.

 

[Lion hunter]

Re: Need some help with a 1977 Mercury 1150 Inline 6!

Those inlines are cold blooded. Like the previous poster mentioned the fast idle almost always has to be used and the choke if it has set to long. Make sure the chock solenid is working and that it's closing the choke.

 

[iraqarmyvet]

Re: Need some help with a 1977 Mercury 1150 Inline 6!

I actually got the same stiuation. I did not put anything down the cylinders, instead I gave a quick shot of carb cleaner in each of the 3 carbs. It took right off after a little choke. These dam things are cold blooded.
Also check you plugs and wires. Wires were cracked and plugs were all gunked up.

Mine will Idle fine but once I try to put it in forward it kills. I took it to a dealer, and they looked at lower unit and they said they adjusted the cables and everything looks good down there. Thats when I found the wires and plugs.

I really should do a compressin test. I have heard of loosing one cylinder.

seen it on other posts here.

work in progress. Wish us luck

 

[Lion hunter]

Re: Need some help with a 1977 Mercury 1150 Inline 6!

Yes, check all cylinders for compression and spark. DO NOT use carb cleaner or starting fluid on a 2 stroke. You were doing it correctly by using fuel mix. Although I would spray the mix in the mouth of the carbs. Should never need more than the fast idle and choke if everything is right. Have you cleaned all the carbs and fuel pumps? A lot of people run outboards w/o a fuel filter for some reason. Junk tends to get caught in the fuel pumps and it starves for fuel, plus sends alot of junk into your engine.

 

[KBADC]

Re: Need some help with a 1977 Mercury 1150 Inline 6!

I read here once that with these motors you should prime the motor till gas drips from the carbs then start it up. Works for me everytime!

 

[rhayes2849]

Re: Need some help with a 1977 Mercury 1150 Inline 6!

1977 Mercury 1150 very hard to cold start takes me about 15 mins. Replaced plugs, check wires and Cap all good. Running 50:1 mix used sea foam in gas tank. Once stated runs great just hard to cold start and after sitting for an hour can any one help?

Thanks