Merc 165 hard to start cold

[jam39vw995]

After a carb rebuild, this engine is brutal to start in cold weather. Any idea what's going on?<br />Once it warmed up it runs great.<br />I've adjusted the choke as per instructions from members here, 3/16 gap on choke plate, and fast idle cam is engauged etc.<br />Giving 1 full throttle pump before hitting the key and it's still a real bear to start.<br /><br />thanks for any ideas on what to check/do next.

 

[B_Eager]

Re: Merc 165 hard to start cold

Check your fuel pump, you may not have any fuel in the carburator to choke with.

 

[daveswaves]

Re: Merc 165 hard to start cold

Check to make sure that when you give it your one full throttle pump that the accelerator pump is actually squirting gas into the carb. You should be able to see it if you look down the carb throat while you pump. If you dont get a squirt of gas it will be a bear to start. Accelerator pump travel may be set wrong after rebuild and/or float level may not be correct.

 

[jam39vw995]

Re: Merc 165 hard to start cold

Thanks, I'll check these things and report how it goes.

 

[Doug Durako]

Re: Merc 165 hard to start cold

If that is the older style mechanical fuel pump on the GM straight six, I had to pump mine three to four full pumps while cranking the motor to get it to fire in cold weather or if it sat without running more than two weeks.

 

[affa]

Re: Merc 165 hard to start cold

Hi<br />I had to set my choke much leaner then the instruction said after my rebuild.<br />I found out by adjusting the choke just when I get it started, does it start fine when its warm?<br />Regards<br />Affa

 

[jam39vw995]

Re: Merc 165 hard to start cold

Yes, mechanical pump, yes pumping helps. 2 or 3 full pumps and it starts.<br /><br />Yes, starts and runs excellent when warm.<br /><br />I will try setting choke leaner and adjust accel. pump if needed.<br /><br />Thanks for the help.

 

[jam39vw995]

Re: Merc 165 hard to start cold

Thanks you guys. I fixed it.<br /><br />The choke was way out of adjustment, I was sure I tightened the screws enough. Reset that, and it is starting fine now after 2 throttle pumps, I have to adjust the accel. pump if I can figure out how.<br />thanks again.