1150 merc help.

[JCJ]

You guys seem to be pretty knowledgeable so....
Merc 1150 ser# 336 9109
I'm trying to track down a mechanics manual but till then I have a few questions.
I had to rewire the boat via wiring diagram I found here. everything seems to
work. When ignition on what should be hot? I have 2 wires to switch box hot, red and white. Distributor side brown is hot ( mercury switch). with ign off red
is still hot. I have not checked spark as of yet. Should coil be hot ign on?

Carburetor. Do they only choke top two carbs or am I missing parts? How finicky is the jetting? I'll be running the boat around 7000 feet. It came from Nebraska not sure of the elevation their.

What are some other good things to go through. I've pulled the lower unit and checked pump and what not. Compression is good. rewired, and re plumbed.
Thanks,
Jerod

 

[robaru]

Re: 1150 merc help.

I can answer the carb questions. Only the top two carbs have choke plates on them. And yes, running at 7000 feet, the manual recommends rejetting from the stock jets which are usually set to run up to 3000 feet or so.

 

[JCJ]

Re: 1150 merc help.

Would you happen to know the jet sizes for my altitude. I haven't had very good luck with search.
Thank you,
Jerod.

 

[JCJ]

Re: 1150 merc help.

I take it .066 jet size is standard. .066 is .066"? The leanest jets I've found are .062. Do you guys know what the correction factor is or where I could find a jetting chart. It seems the main jet is the only changeable jet? I was thinking of jetting somewhere in the middle and live with it being maybe a little lean around 5500' and a little rich around 7000' as I don't plan on re-jetting every time I go out.
Thank you,
Jerod.

 

[Chris1956]

Re: 1150 merc help.

Red wire on the switchbox is always +12VDC. White wire below it is the ign accessory wire and it hot when you want the motor to run.

The Merc manual for that motor has all the main jets suitable for altitude listed. If I get a minute, I can look it up later. Send me a PM with the best guess of altitude and I will send you the jet size. Does that motor have backdrag jets, mounted on the carb bowl covers?