Engine needs full choke to idle

[David Pugh]

Hi all; I have my engine running now but I can't seem to get the right combination w/ the idle adjust, idle speed and choke.

The only way it will run is in full choke. With the idle adjust I have gone from closed to 2 turns and when I attempt to open the choke it dies. I think the problem is me, I am not doing something right.

Next I placed a plastic bag over the fire arrestor and no change in the RPM. So I removed the carb. again and replaced the flange gasket w/ non-hardening permatex on both sides. Now the engine runs much smoother but still only on full choke.

I think after the rain quits I'll go for a ride and see what happens.

Any ideas anyone???

Dragonfly Dave.

[Al Schober]

Dave,
Sounds like your carb needs cleaning - a clogged main jet will give the symptoms you describe. Needing choke to start when cold is usual, but the engine should run smoothly without choke after a minute or two.

[David Pugh]

Cleaning the carb again!

Thanks Al;
I think I'll order new gaskets first so I can get it right this time. I had a feeling it needed another cleaning.

Dave

[Al Schober]

Dave,
Have you given any thought to the source of the crud? Is the tank clean? How are you fixed for filters? My last bout with carb crud was caused by grit coming from the secondary inline filter, which was rusting away internally.
Cleaning the carb once is OK, but it starts to get old real quick. Personally, I'd rather be sailing (grin).

[67c&ccorv]

Hi all; I have my engine running now but I can't seem to get the right combination w/ the idle adjust, idle speed and choke.

The only way it will run is in full choke. With the idle adjust I have gone from closed to 2 turns and when I attempt to open the choke it dies. I think the problem is me, I am not doing something right.

Next I placed a plastic bag over the fire arrestor and no change in the RPM. So I removed the carb. again and replaced the flange gasket w/ non-hardening permatex on both sides. Now the engine runs much smoother but still only on full choke.

I think after the rain quits I'll go for a ride and see what happens.

Any ideas anyone???

Dragonfly Dave.

Are you certain the choke plate linkage is properly hooked up - it's very easy to get the linkage ass-backwards.

And do you have a MMI manual?

[David Pugh]

Still choking engine!

I have the engine running good @ idle speed 750-800rpm but still full choke. I went for a short ride in the creek and the manifold does not get hot, the head is plenty hot.

Could this be the reason why I am unable to open the choke? After all the intake air is passing through a cold manifold. I have read in other posts about the bypass valve or a closed system, could this be what I need to do?

If so where can I find a diagram on the closed system?

The crap I have been dealing with is from the previous owner who installed a new plastic tank and lines which I ended up throwing it all away, a total botch job. After I installed all new tank lines and filter and new carb I still had problems with crap. I think it was lodged in the fuel pump and I did not clean that until later when I rebuilt the fuel pump.

So for now with all new filters I removed the carb and cleaned it, I pumped raw gas into a glass and saw absolutely no crap.

I'm sure the choke is hooked up correctly and I do have a MMI manual.

Share your thoughts, Dave.

[Dave Neptune]

David, if you indeed need the choke on to run, THERE IS SOMETHING WRONG WITH THE CARB! Either there is almost no fuel pressure or the float is way to low or the carb is still plugged up somewhere.

RE the temps no concern, the engine should run without the choke when started cold after less than a minute, however it will take a ew minutes for dead slow idle.

Do you know the fuel pressure at the carb?

Dave Neptune

[edwardc]

Another possibility is an air leak, causing the mix to be way too lean, requiring extra choke to compensate. Check the gaskets at the main carb flange, and between the two halves of the carb body. You can test with small sprays of starter fluid along the gasket. Any change in RPM will indicate a leak.

Also, if you've got a PCV valve add-on, make sure the vacuum line to it is securely hooked up and sealed.

[JOHN COOKSON]

Now the engine runs much smoother but still only on full choke.
Dragonfly Dave.

How much smoother is "much smoother"? How about correctly?

Once you're sure the carb\fuel side is correct and are still have problems
check the timing. If you can move the body of the distributor by hand it is way too loose. Also are you running on three cylinders?

TRUE GRIT