6.75HP auto choke not gaining full RPM

[Pet982]

About 1.5 years ago I started tinkering with 6.75hp auto choke that would not start without spraying gas down the throat of the carb.


I just got some time to start tinkering again and now it will start up without manually priming. I will run at a low RPM for a quite a while, at least 30 sec to over a minute without ever fully picking up RPMs. I can move around the governor lever but there is no affect on the RPMs. It will once and a while for a sec or 2 go up to full RPM but then just fall right back to low.

Is it possible the compression release is sticking in the released position? or would it not run at all?

I put a brand new aftermarket auto choke carb with no luck

I tried changing it to a primer style carb. with no luck.

It now has the new auto choke carb on it.

Verified the auto choke system was working correctly.

Did a leak-down test.

on the HF tester it showed in the green (20% ish). I also used the tester on a Briggs Quantum on a yard vac and that showed 30% but that engine runs like a champ.

 

[Boudreaux In Eunice La.]

I think you have a spring issue somewhere........... The gov spring or the choke spring.........

What gov did you move by hand ???? That plastic vane near the flywheel ???? On the small Briggs that is a wind driven gov.

On yours you have a mechanical gov........ Here is a video I made a while back that might help you.... I need to redo this video since I got a new set up......

Hope this helps you.......... Let us know Mon Ami ~!~!

https://youtu.be/qOm-D93Y9-k

 

[Pet982]

When its running (low RPM) and I move the throttle lever attached to the carb plate there is no change in RPM. The lever at the other end of that, under the gas tank, is attached to the governor on the crank, correct?

The choke vein will open with the flywheel wind but not fully because its not spinning too fast, but when the bi-metal control opens from heat it will stay open. And if I wiggle that around there is no RPM change except when I hold it closed it will stall out.


The only RPM bursts are random and only for a split second but then it will drop right back down.

I can get spring pictures and post them to see if you see anything out of place. But the choke plate holds closed and opens with wind, the throttle also holds closed but does seem to have a lot of resistance to open.

 

[Boudreaux In Eunice La.]

Sorry about the late reply..... I just got back from vacation... I cut it short a day or two because I had to come back home and rest..... Working in the shop is easier than on vacation LOL....

Let me know if you still here ~!~!