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MG TD TF 1500 - 53TD smoking after 15 minutes

New 53TD rebuild by pro shop. Runs well at first. After about 15 minutes it smokes badly and runs rough. Any ideas?
Robert Goodling

What colour smoke, and what does it smell like
William Revit

Smoke from a rebuilt engine can be quite normal until everything settles down, the rings bed in and any volatiles are driven off. Running rough could be associated with the same process or another issue.
Dave H
Dave Hill

Valve seals, missing or installed incorrectly. I had exactly the same issue. When I took the head apart the valves seals were installed incorrectly.

Tim
Timothy Burchfield

You're probably right Tim, it's unbelievable how many times they are fitted wrongly, and by so called reputable operators mostly-and especially so if the shields are missing off the springs-I was thinking maybe a cracked head leaking coolant in-hence the question on smoke colour but valve stem seals would make sense
willy
William Revit

Could It be sucking oil from the air cleaner. I have been lowering the amount of oil in the base but still smokes. Maybe element is saturated? Thanks for your concern.
Robert Goodling

After driving, ideling, or does that matter?
George Butz III

If it runs well and doesn't smoke until the engine gets hot, at which point it both smokes and runs badly, then I'd suspect the carbs are running rich. Try leaning out the carbs and see if the problem goes away or at least gets better. Obviously you will require more choke than before until warmed up. Could be other things but that's where I would start.
Steve Simmons

I would never give my engine to anyone who was not familiar with the XPAG. Pro builders usually dont know the nuances of this engine. saw many a blown engine done by so called special engine builders who dont know what an XPAG was.
TRM Maine

Robert-If you think it could be the air cleaner, try taking it off and give it a go without it
What colour is the smoke and what does it smell like--?
William Revit

Check that the top cover of the air cleaner has not been tightened down too much. In extreme it can reduce the air flow and richen the mix.
Ray
Ray Lee

Robert,

We can eliminate 2/3 of the guesswork if you tell us the colour of the smoke.
1/ black smoke = petrol (gas)
2/ blue smoke = oil
3/ white smoke(steam) = water (coolant).

John
J Scragg

HEAD GASKET !!!!!
SPW Wincze

John Scragg left out one other smoke, white Lucas smoke.
P G Gilvarry

If the air filter is overfilled, it would run rich and rough right from startup.

Pull the plugs and check if one, two or all four are black. That may narrow down your detective work.

Double check there is an oil banjo bolt to the head with an orifice or at least a hole smaller than the block banjo bolt. Too much oil to the rockers could drench the valve stems.
JIM N

This thread was discussed between 16/09/2019 and 19/09/2019

MG TD TF 1500 index

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