Throttle linkage

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jimjumper
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Joined: Thu May 19, 2016 8:56 pm

Throttle linkage

Postby jimjumper » Sun Jul 30, 2017 3:13 pm

I finally got around to diagnosing a low RPM problem on my 240D. With the the throttle fully against the stop I was only getting about 2000 RPMs. I initially thought maybe the rack was sticking and pulled off the cover where the lever is attached by a spring to the governor. Pulling on the spring while running got full 2400 RPM's so my first thought was to shorten the spring wire but I noticed that the lever still had space to move rearward. I followed the linkage down and discovered a small screw with a hole thru the head with a wire type lead seal attached to a locknut. When the throttle is fully pulled to the stop the locknut butts up against the injector pump and limits the full throw of the lever. I removed the seal and nut and that allowed the lever to be pulled fully back and got 2400 RPMs then. Any idea what that seal is for? It appeared to be factory but I can't imagine why the factory or the refurb guys would want to physically limit the rpms. In any case, I got it working the way I think it should but just scratching my head as to the thinking for the limiter screw.

winston
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Location: North East Texas

Re: Throttle linkage

Postby winston » Mon Jul 31, 2017 5:59 am

My theory is the seal served as a warning not to exceed the recommended set rpm.

Are you confident you tachometer is reading correctly?

jimjumper
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Posts: 31
Joined: Thu May 19, 2016 8:56 pm

Re: Throttle linkage

Postby jimjumper » Mon Jul 31, 2017 7:54 am

I am fairly sure it is. I was initially suspicious when I was only getting 2K max, so I put in a new tach and cable and got the same readings. I have a Harbor Freight tachometer that I'll check it with this afternoon.

jimjumper
Volunteer Poster
Posts: 31
Joined: Thu May 19, 2016 8:56 pm

Re: Throttle linkage

Postby jimjumper » Mon Jul 31, 2017 4:12 pm

Checked it with a tachometer and pretty sure the tractor tach is close to correct. I was getting a lot of oddball readings from the handheld tach but got enough readings at various speeds to be pretty sure that they match pretty close. I'll be really careful and check it for overheating every half hour or so for a while.


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