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MG TD TF 1500 - TD engine runs rough when warm

I have a '52 Mark II TD.

The engine idles fine, but when it's warm, and I let out the clutch in 1st gear, the engine stumbles and bucks as if two cylinders are not firing.

When I push in the clutch and let the engine return to idle, the engine runs smoothly.

I have gear-head friends who have offered opinions. Some say one of the carburetors is not operating normally, and I need to have the carbs rebuilt.
Another says the flywheel might be loose. Another says I have it has valve problems.

Any suggestions?

Erick Blackwelder
Alexandria, Virginia

EB Blackwelder

I doubt seriously it's a loose flywheel...I'd ignore that gear-head.

I'd check timing first - make sure it's about 5 - 7 degrees BTDC at idle.

If timing is good check the balance of your carbs.

Gene Gillam

I think Gene's on the right track. Check to see your carbs are both syncing correctly. If the connecting rod isn't tight at the connections, it could be that at minimum throttle they will run nicely but when you accelerate, only one of the carbs is responding....
Geoffrey M Baker

Start checking basics- pull the plugs and see if fouled, always good to try new ones anyway. Check compression, should be even between all cylinders. Remove the air cleaner/manifold and make sure both carb pistons rise equally. Clean, gap and check points, etc.
George Butz

Erick,
After you do get the car moving ,, how does it react through the rest of the gears???? You indicate that this happens when the engine is warm,, so do you mean that this does not happen when you first try to go up throught he gears befor the engine gets tio normal operating temp?

SPW
Steve Wincze

Thanks guys for your help. I will follow your directions: Balance the carbs, and check the timing.

Steve, yes, the engine runs rough in all four gears.

Erick Blackwelder
Alexandria, Virginia
EB Blackwelder

Erick,
But it only happens when it (the engine) is warm, and not when it is first started and it is "cold"????

SPW
Steve Wincze

Steve Wincze, the engine does not stumble or sputter when it is cold.

Erick
EB Blackwelder

Have you had a chance to set the carbs?? ie balance, mixture etc?
Steve Wincze

I suggest that you check your coil. Sometimes they get an internal short that only makes trouble when hot.

Put a new one in and see if it solves your problem.

Mark Sherman
Mark A. Sherman

Next time it run rough, pull the plugs and see if two are wet or really black. You then can deal with that carb.
JRN JIM

Is the distributor grounding against the tach gearbox on the back of the generator? Regards, tom
tm peterson

This thread was discussed between 30/06/2014 and 12/07/2014

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