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MG TD TF 1500 - Throttle Link Adjust and Idle speed

My idle screws are up as far as can be and still I am idling too fast 1500-2000. (What should idle be - 800 rpm?) I see there is a throttle link that goes directly to the foot pedal rod but can find nothing on any youtubes etc. Will adjusting that link help give me more room to bring down the idle on my TF?
K E MURPHY

Keith, look and see it the brass stops where the idle screws pass through are resting on the "shelf" of the carb bodies. Check both carbs. My guess is one of of the two is not. Could be the fast idle from the choke is holding it up...or perhaps the throttle linkage as well.

You can disconnect the linkage at the carb and see if that makes any change and if so loosen the nuts and screw in the rod to allow the carbs to fully close.

Another possibility is that the butterfly plates have been put in backwards and won't allow the carb to fully close.
MG LaVerne

Your engine should idle well below 1,000 RPM. Is this a new condition? What have you done to the car recently?

First pull the end off the linkage where it connects to the carb to see if it is the linkage or the carb. If there is no change in speed, then it's the carb. If it drops way down, it's the linkage (adjust this by loosening the locknuts and twisting the rod to change the length).

On a TD (I assume you have one) there are 3 carb screws no note - 1 for idle, and 2 for balance. If you loosen the balance scres you will have to re-adjust. You should be able to see if one or more screws are against the stops on the carbs.

Check to see if the carb can be slowed by pressing hard on the linkage ball - you may have a binding throttle plate. You should follow the WSM instructions about the basic set-up the screws, linkage, connectors, etc., and balance the carbs It's remotely possible you may also vave an air leak.

Tom
t lange

Help! I just loosened the throttle link lock nuts and turned the link 4 or 5 turns in either direction and it made no difference. With the idle screws backed all the way off it still idles at 2000 -2200 making it a b*^#ch to get into gear! BUT YES if I push down hard on the linkage ball it slows it down! Then when I release it pops right back up to 2,000. My mechanic went through yesterday and tuned. I just restored it over 8 years, but engine sat while body was finished. I have driven it about 300 miles. He said he couldn't get it slower because it needs to break in more??
I am afraid to mess with the other screws and get the carbs out of sync. Can I adjust some of it to get it lower without messing with the sync of the carbs? Help! I have adjusted way in the past, but really don't want to take the air cleaners off etc on the TF as it is a bear.
Keith
K E MURPHY

My butterfly's were installed backwards by PO making it impossible to close them far enough, hence a fast idle. They are beveled and there is a right and wrong way. I would ask your guy if he was aware of this. If not, you have a 50% or getting them backwards.
Ed
efh Haskell

I see my friend LaVerne posted an answer - I was just talking about you last week!! My neighbor was saying how fun and crazy we were to drive the ocean to ocean in 2012 MG to Reno. I said no, and told them about the guy who first drove from CO to MD so he could start out at the coast! They said they guessed craziness was relative, and I didn't seem so crazy now!
K E MURPHY

Hi Keith,

Hope you locate your issue (and I would add to the above suggestions the possibility that the carb bodies themselves may need to be repositioned slightly on the intake - this sometimes causes binding of the interconnected throttle shafts).

To add to what Tom mentions above - the two air intake balance screws also serve as your general idle adjustments (there is not a separate idle screw). The third screw that sits on the front carb boss adjusts the "fast idle" only (which comes in to play when the choke is used) and should not be used to increase or decrease your normal idle.

I agree with LaVerne and Ed that you need to pull your filters (they are not that difficult to remove) and check the discs for proper centering, free movement, and orientation - If the throttle shafts were pushed to far towards the center connecting piece when tightening the small clamps, the throttle discs can jamb up

improperly centered jet housings may also be binding your damper pistons - which will cause the car to run fast - but this condition would not be impacted by pushing down on the throttle joint ball - which you mention you did .

Let us know what you find!
DLD

Get a copy of the NEMGTR's "The T-series Handbook" and/or look at Dave Braun's carb tuning info. If you understand the mechanism and how/why they work, tuning will make sense and be easy. Suggestions above right on. Very important (do this first): make sure the individual throttle shafts don't bind, and that the springs on the outer ends are adjusted so they snap shut. Remove the throttle shaft to pedal link from one end (don't adjust, remove it), and loosen the center coupling to verify freedom/snapping shut of each individual shaft. That must happen or nothing else will work. George
George Butz

Thanks to all, I will take to heart. Guess since my mechanic didn't get them to work I will have to do myself! When we restored the car, the carbs worked great, so as to not have that to worry about, we just took off and set aside. I do have the T Series handbook and about every other one - but like my exercise equipment and guitars, nothing happens unless you use them! Will let you know how it comes out. Guess if I take the cleaners off, might as well use my uni-syn?
Keith
K E MURPHY

Does this look familiar?

MG LaVerne

Or maybe...

MG LaVerne

Thanks for the great pictures! Grandkids!
K E MURPHY

This thread was discussed between 28/05/2014 and 30/05/2014

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