78 150 merc no start

[stealthdrummer]

I just got a 1978 Champion bass boat with a 150 Merc on it. The motor spins over great but won't fire unless you hit it with starting fluid first. After that it seems to run fine. I must admit I haven't had any time to get into it as I just brought it home today. If you squeeze the primer bulb it never really gets hard and you can hear a small amount of air when squeezing. I am guessing that is the problem but looking for any ideas. Also the trim will go up great but seems to struggle coming down. The pump makes a high piched whine when trying to come down. That sounds like I need a new pump, correct? Or I might just have to check/add fluid to the pump.....like I said will know more tomorrow.

 

[Chris1956]

Re: 78 150 merc no start

Did you choke the crap out of it? They need some choking to get running when cold.

Low compression will also cause you to need starting fluid, but don't use it as it is bad for lubrication. Use some 50::1 mix instead.

 

[stealthdrummer]

Re: 78 150 merc no start

I didn't use any starting fluid but the previous owner did a few times. Yea I hit the choke button and made shure it was working correctly (had the cover off) and cranked it over but still no start. Can't get the primer bulb to get hard. Going to try and replace that and see what happens. My wife and I spent most of the day cleaning everything in the boat. It was quite nasty but that was also reflected in the purchase price. It's amazing how much better it looks cleaned up.