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MG TD TF 1500 - Fitting valve oil seals

has anybody fitted new oil seals using the rope down the plughole method. It sounds OK but also a bit of a tall story.
I have tried the air pressure method but find it difficult to break the collet grip.
Any replies appreciated.
Ray TF 2884
Ray Lee


There is at least one more method, and that is to pressurize the combution chamber with an adapter in the plug-hole.

Here is a pick of the best valve seal I have found so far. Its not my idea but I have since replace the almost useless donut o-rings with the Feldpro SS70373 umbrella seal, easily available here and I suspect, not too difficult to find in the UK.

Gord Clark
Rockburn, Qué.

Gordon Clark

Not a 100% sure, but I'm pretty sure that's the same one that is used on the Chevrolet small block motors....
I used them on both of my "B's" , with great success....
I think that Ray has already tried the pressurized air method....
Just stuff a smooth nylon rope in there, at TDC, and keep stuffing until full....
John Twist has a great video on U-tube that shows how it's done.
Edward Wesson 52TD

I've used 'the rope' on other cars successfully,
attached is a picture of my valve seal.

I presume they are of German origin because I got them from the father of my wife. He is very much into Audi's and NSU's.

Willem van der Veer

Could you advise me where I would get the Feldpro umbrella seal. I certainly like the look of it, and as you have good success, I would like to get a set for my TF and Laystall heads.

George Raham [TD4224]


Got mine at NAPA.

... just Google Felpro SS 30373.

Gordon Clark

You stuff the rope in at something BEFORE tdc..then use the hand crank to compress the rope against the top of the combustion chamber. Regards, tom
tom peterson

Thanks for upgrading my comment.
Edward Wesson 52TD

I've used the air pressure method successfully on many engines. While holding pressure on the valve spring compressor, rap the valve spring retainer with a nylon hammer. When you develop the right feel for it you can move right along. The blow is not quite straight down but a somewhat sideways hit. I give the retainer a good hit first with just the air on it first. You can see when you've made the keepers loose their grip.

Of course the rope works too, just slower. My compressed air is at 175 psi.
J E Carroll

Rope works fine, but use a very pliable cotton type rope. The nylon type ropes, stiffer, don't work.
L Rutt

Thanks for all the info,the job is for a friend who has the seals ready. I think they are late "A" series Mini,midget,Metro Etc.
Ray TF2884
Ray Lee

I tried seals for the Mini but they slid off. Maybe because I have bronze guides without a slot to hold the seal?
Willem van der Veer

There are two nylon rope types available....One, is very stiff, and the other is as soft as any cotton rope....Costs more, but never wears out.
Edward Wesson 52TD

After my first 6000 miles I still was unhappy with oilconsumption and that is why I placed such seals. But no difference in oilconsumption.
Close inspection (magnifying glasses) I found the valve stem surface pretty rough AND it had an inscription: a part number plus the proud text "made in England" and this text would pass the seal every time so kind of pumping oil down towards the combustion room.
After that I shortened the valve guides with 4 mm and polished the stems. Just waiting for some better weather for testdriving now.
So, could be worthwile to carefully check your valve stems for inscriptions and roughness. A magnifying glass plus strong light will do. Without these, it is hardly noticable.
I agree to other comments that air plus a tap on the valve stem easily loosens the cotters. And just for safety I had a safety wire at the valve. And put the piston in that cilinder on TDC (car on handbrake and in gear to avoid the air moving the car) to avoid any risk on a fallen down valve.
Good luck, Huib

Huib Bruijstens


This is a Tranco valve. In its day, comnsidered to be the best exhaust valve available. Made by Farnborough Engineering of high Silicone Chrome steel. They were years ahead in exhaust valve technology and everybody used them, including MG.

I put a set into my Cooper 970S and they just didn't burn, especially at high revs, which this variation of the Cooper engine was famous for.

I have no idea what became of Farnborough or the Tranco valve. I just know that it was a performance valve of choice in the 1950s and 1960s.

One occasionally sees a set on EBay.

Gord Clark
Rockburn Qué.
Gordon Clark

Thank you Gordon for this background information. Greetings, huib
Huib Bruijstens

finally got round to the seal job. Took off valve cover and found all the valves except No3 had oil on the valve caps, exhaust had split "0" ring and inlet ring misplaced. Fitted new "O" rings and re-assembled . Ran the car around until really warm then trickled around for a few miles which had been causing No4 to oil the plug, result plug now clean
So those little rings really do do something.
The car is a YA and the first time I have driven one and quite enjoyed it.
Ray TF 2884
Ray Lee

What are you using to compress the springs and remove the cotters when you're using the rope trick?

Photo would be appreciated!
Gene Gillam

The Y-Types or "One and a Quarter Litre Saloon and Tourer are excellent road holding and very pleasant cars to drive. It is a well kept secret Ray - you will enjoy the car even more when you tune it up for modern fuel.

Happy days

YT x 1
YA x 3
TA x 2
VA x 1
and a few other modern MG's

this compressor was just a temporary device to test its use before I make a permanent one.
The long stud is the rocker cover stud which I screwed into the rocker pillar hole to act as a pivot.
The hose clips let me get the leverage correct.
The lever needs to be substantial as you can see from the bend.
The new one will have a ratchet to hold the spring compressed while I remove/replace the collets without removing my fingertips.
It worked perfectly so I can now make a proper one for the next time.
Ray TF2884

Ray Lee

Just re-read my post (26th).I meant to say that the valves in No4 cyl had drained off their oil because the seals were U/S
Ray Lee

Thanks might want to consider going into business with those!
Gene Gillam

Hi, it has taken me a long time to get round to it but here it is.Another friend thought he had a valve seal leak so I had to make a more professional compressor.

Ray Lee

And for those interested a drawing of same.

Ray Lee

As a heads up on Farnborough Engineering
I used to live in Orpington next to Farnborough in Kent. Had a school friend who started work at Farnborough Engineering as a tool setter. I believe the factory was taken over by the America Firm TRW - but we are working on 40 year old memory¡¦s here ...ƒº
They told the work force that all jobs were to stay in place and nothing was to change. Within a few year all were let go and the factory closed and was demolished.
My guess was, the competition could not stand the quality of their work ¡V so they just removed it.
And you are dead right. Up to the 1980¡¦s their Tranco valves were the best you could get. Not so sure now though!
R. D. Jones

We used sodium filled aircraft engine valves on a couple race engines and worked very well. Always trying something different. Did they ever use them in British engines? PJ
Paul S Jennings

The MG Metro Turbo had sodium filled exhaust valves.
Willem van der Veer

This thread was discussed between 11/04/2013 and 31/03/2015

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