Cold idle

[8x56mn]

Hey guys, I have a concerne, when I start up my MC 4.0 140 it idles ruff for a few minuets and then smoothes out and the idle speed climbs to where I have to back off the throttle. Is this a normal warm up condition or do I have a timing issue.The engine starts right up aftetr a couple of pumps.I have noticed that while trolling at 1000 RPM's using my Happy Troller it will skip ever so often. Is this abnormal condition when running so slow? I know if it runs don't fix it right.

 

[ron7000]

Re: Cold idle

the startup rough idle then increase of rpm is due to too much choke and the engine running too rich dropping the rpm. Adjust the choke so it has less closing tension when cold, that way it'll open sooner and the motor will smooth out sooner or be smooth from the start. This is normal however.<br /><br />At 1000 rpms, the motor should not skip at all. Odds are it's a carb/fuel issue, might just need minor carb adjustment or overhaul.<br /><br />if it runs right, then nothing to fix,<br />but don't let a potential problem compound itself into a bigger one.

 

[8x56mn]

Re: Cold idle

Thanks I will try that. There is a small and what looks like a adjustment screw on the right side of the carb, is that for choke tensioning. I remember seeing it, but never paid any attention to it to see what is actualy does. Thanks for your reply. <br />I guess I made somebody mad, I'll keep my opinions to myself from now on.

 

[Bondo]

Re: Cold idle

Ayuh,.... I Agree with Ron,..... It Sounds like All of the Issues mentioned are Carb related,.......<br />

I guess I made somebody mad, I'll keep my opinions to myself from now on.

Did I miss Something,.??.....

 

[ron7000]

Re: Cold idle

i missed something too I guess <br /><br />the adjustment screw you mention is probably the idle mixture screw. For choke tensioning, there's a spring loaded piece on the side of the carb and what you do is loosen the cover and rotate it. One way will increase tension and want to close the choke flap, the other way will open it.<br /><br />best i could do for a pic, yours won't be exactly the same but will give you a good idea. #69 are the idle mixture screws, here there's 2, you may only have one but will be in the same relative location. <br />The choke is item #7 and the spring and cover of it item #3. You loosen the cover and rotate it.<br />

 

[Gary H NC]

Re: Cold idle

The Choke has a round black platic cap over the spring.3 small screws hold the cap on..it's usually on the side of the carb and has small adjustment marks for richer or leaner.loosen the 3 screws and turn it a notch torward lean..<br />Number 3 on rons diagram above..Sorry Ron..We must have been posting at the same time.

 

[8x56mn]

Re: Cold idle

Thanks to everyone, I totally understand, should be simple to adjust from the description. I did recall seeing the adjustment device and will take care of it on Saturday. Now I just have to worry about the starter solenoid. I had to jump across the terminals to get it to engage while holding the key on. It worked fine after that, BUT I suppose it's just a matter of time before it happens again. Also I seem to be getting some water in the bilge, but can't for the life of me see where it's coming from. Only happens when I'm running, which would make the bellows suspect, but I don't see any water coming in the hole. The bilge water does leave a slight oily film on the top of water after pumping. Again thanks to everyone.