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MG TD TF 1500 - fouling plugs

OK out there, here's the latest question. My 53 TD uses a quart of oil in about 200 miles. The only leak I seem to have is the rear seal which is a spot as big as your fist when I stop the engine. I have between 170 & 180 lbs. of compression on each cylinder. The plugs get very black and carbonized after 200 or so miles. The exhaust does not appear black but there is soot in the exhaust pipe. Could this be a timing problem? The car runs " OK " but I get a little run-on when I turn the ignition off. I know the carbs are not quite right but can they cause this problem? The head is a replacment that I had machined and new valves & guides installed. Also I had the valve " oil seals " renewed. Thanks for all the responses to my past questions, you people are great! Tom
Thomas McNamara

Tom - Bring me up to date on your engine. Has it recently been overhauled? If not, how many miles do you have on the last overhaul? Is the rear oil seal leak a recent happening, or has it been there for some time (perhaps getting progressively worse)? Do you get a lot of oil smoke (blue or blue/white) when you are driving?
When I had a problem with oil compsumption (150 miles to the quart) I had put over 80,000 miles on the last overhaul (most of those miles at 4200 RPM) and the engine was quit simply, worn out. Compresion was good, but I was still getting a lot of blow by, which was blowing oil out of the breather pipe and oil was getting past the oil control rings and into the cylinders. The one thing that I didn't have a problem with, was the rear oil seal - I've never had a problem there so far.
Ignition timing will not cause an engine to run rich. The problem there (sooty deposits in the exhaust pipe) is carburetor adjustment. The run on that you are experiencing is possibly (probably) due to having the timing set too far retarded and to compensate for this (ie. getting the idle where it belongs), the idle screwsare run in further that they should be. This condition results in the throttle plates being too far open when you are at idle and the engine is pulling fuel into the cylinders and dieseling after you shut it down. You need to set the timing correctly, then adjust the carbs for the correct idle speed. If you will e-mail me directly, I'll go through an easy way to set the timing correctly. As for the oil conpsumption, you will probably have to tear the engine down to correct that. If/when you do that, check that the piston clearance in the cylinders is not excessive.
Good luck - Dave
David DuBois

I bet the carburettors are not adjusted properly and the lean/rich mixture is not right.

Debus
Denis L. Baggi

check the hole in the small tube coming from the valve cover.it should be restricted to about 1/8".this will restrict the amount of oil being drawn into you engine and cut down oil consumption.
sandy sandersfkorida

Sandy - did you narrow the banjo bolt in the oil feed to the rockers yourself, if so how did you do it.?

Thomas - do you get lots of smoke out of the exhaust when you accellerate away having descended an incline with trailing throttle?
If so - worn valve guides could be the problem.

john
John Thomas

OK guys, thanks for all the input. Turns out that I had sealed the valve cover breather pipe in fear of oil splashing out as I do not have the original air cleaner. I found a chromed breather cap in an after market store and the problem appears to be abated. Could I have been creating a positive pressure in the valve cover, thereby forcing oil into the open valves?

Speaking of air cleaners, I now have the pancake type and the front one rubs on the radiater braceing bar. Is there a fix for this? If I bend the brace bar it will become shorter and may not fit. Perhaps just flatten the pancake rim to clear? Thanks again, Tom
Thomas McNamara

Hi Tom;

Go ahead and bend the bar. Mine is bent down one and three quarters inches at a point ten and a half inches aft of the front mounting bolt. This provides adequate clearance for my Stellings and Hellings air filters. There are still enough threads available on the front mounting fork adjustment to provide about an eighth of an inch clearance between the front and back edge of the bonnet to body/radiator.

Good Luck
Dick
1952 MG TD
Dick McCutcheon

Sorry Gang;

I obviously had a senior moment with my posting. It should go to another thread. I hope you will forgive me for the mistake but sometimes.......!

Dick
Dick McCutcheon

This thread was discussed between 10/07/2000 and 04/08/2000

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.