MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - Hole in the valve cover.

Car is 1955 tf1500. Valve cover has the hole where I suppose a line went to the carbs. What happens if this hole in the valve cover if shut off so it can not breath (as mine is)??? Anything Bad ???. Anything good ??. Anything?. Thanks Dave.
capdave

Dave,
If you are running orginal Volks type air cleaners should be a hose to back of forward filter. If running aftermarket air cleaners (think yours are same as mine) they make a "breather plug" to put on the orginal type valve cover to plug this. Some of the aftermarket covers do this through the oil filler cap.
The valve cover on my TF when purchased had a pcv valve stuffed in a rubber hose held on with a zip tie!
I did not notice any differance when replaced with the breather cap other than eye apeal!
Not sure if damage could occur but given the way old cork gaskets work I would think worse case would be oil might find the weakest point in this "seal?" and leak all over your pretty new engine! Moss sells the "breather cap" ...I might even have a spare...seems mine came up missing at one point and blew oil all over the inside of my compartment but I think it re-surfaced durring recent tear-down. Let me know if you are in need and I can try and locate it.
David #A1
David Sheward

It is important that the rocker cover breathes and blovking up the hole will stop it breathing. A problem with XPAG engines is sump compression and whilst there is venting through the rocker side panel gasket (cut a hole where it fits the breather pipe) the rocker cover vent is important. Normally on pressewd steel covers there is a pipe to which is attached a pipe (rubber & steel on TF) which fits the air filter.
Bob Marshall

Dave,
Maybe I did not make it clear that the "breather cap" I was speaking of does indeed allow the cover to vent...only that it does this through a baffled vent that keeps the oil from spraying out if the hole is left wide open with no fitting to an oil bath type of air cleaner. If you have never run an XP(A/E)G type engine with the cover off you would be amazed by the amount of oil "thrown" about in there! The very nature of the design of our motors (push rod) requires this to insure proper cooling of the exhaust valves and proper lubracation of the camshaft. Very important to the life of the engine this "cooling" process is not restricted or you could easly burn a valve! In it's day this was a big improvement over "side valve" motors of this era. This was pretty "hi-tech" back then! This design is also why our cars are so noisey and thus no doubt why many turnned to aftermarket valve covers made of heaveier material to quite them down. If my limited understanding of the engineering of this engine is correct...it should be noisey...if adjusted to the point where it is not..it won't last very long as the cam will soon wear out and the valves will soon be "toast"! That, and as we know the stock cover was (simply put) butt ugly! If I am wrong here ...I am sure others with a better knowledge of this will no doubt correct me as I am by no means a master macanhic.
Cheers,
David #A1
David Sheward

This thread was discussed on 16/08/2002

MG TD TF 1500 index

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