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MG TD TF 1500 - valve stem oil seals

Does anybody know if there is a modern style valve stem oil seal that fits over the valve guide that will fit an MG TF 1500 engine.
Thanks for your help
Paul
New Zealand
P Hicks

Ones from a late BMC A Series engine fit a 1250 so I suspect will also do for a 1500. You only need them on the inlets and you will have to dispense with the shrouds that fit inside the springs. The seals really need a groove cutting in the guide to prevent them lifting. I have heard of this being done with a needle file which means the guides can be left in place. If your problem is exhaust smoke this is often caused by the original seals being wrongly fitted. They should be placed in the "washer" that the collets are fitted into, under the collets. They are often simply slipped over the valve stems. When running, oil collects in the recess in the "washer" and without the original O ring seals runs past the collets and down the stems. You can test to see if they are OK by removing the rocker cover and seeing if the oil around the collets drains away. The shrouds inside the springs prevent oil splashing on the stems.

Jan T
J Targosz

You will find that opinions vary. There are those who feel the modern or umbrella seals do a great job, and there are those who feel that new seals permit the flow of too little oil to lubricate and cool. There are those who state that the original o-ring design allowed just the right amount of oil, if properly installed, and those who feel that nmodern seals must offer an improvement.

I am of the o-ring school - they work fine for me. I have worked on perhaps a dozen engines where I have found the o-rings erroneously slid all the way down the valve stem, rather than being retained just below the collets in the valve groove. When installed properly, they work perfectly well.

Tom Lange
MGT Repair
t lange

A tip when fitting original "O" rings. Cut the conic tip off a cartridge nozzle at the valve stem diameter, slightly chamfer the inside. Slide on the ring and push into place over the stem with a small ring spanner.
This saves your finger nails and the rings from damage.AsTom says it is important that the rings are compressed by the collets.
If you take off the rocker cover after a run ALL the valves should retain some oil on the caps.
I have renewed the seals on my own and friends engines without removing the head from the block.
I only wish I could be out there doing things like that now.
Ray TF 2884
Ray Lee

I stock Teflon Positive Stop valve stem seals. More than 60,000 miles with no issues. Recommend set of 8 for all valves.The top of the guide needs to be machined to fit.
Len Fanelli
Abingdon Performance Ltd.

Len Fanelli

I'm with Tom lang, The O rings, if instaled properly, are very good and have never given me issus in 50+ years of owning a TD. I did find a friend in Bielefeld Gremany with a TC that had been worked on - where they had installed the top oil deflector to the bottom. Which has the action of forming a pool of oil around the valve stem and it smoked really bad. Simple fix and problem resolved.

Rod Jones

I have had excellent success with the Feldpro umbrella-type seals. They completely cover the valve stem housing and I certainly can't report any leaks for the several years they've been in place. Actually they're off a Chevrolet 140 in-line 6.

Affordable and easily available from NAPA - Picture attached.

Gord Clark
Rockburn, Qué.

Gord Clark

I agree with Tom. I have been playing with TC engines for about 50 years and have never had trouble with the original system. The problem has often been that people push the "O" ring on to the bare valve stem before fitting and compressing the valve spring and top washer. In this situation the "O" ring does nothing but float uselessly along the valve stem.

Correct method: The valve washer and springs must be compressed, then the "O" ring fitted, followed by the collets (wedging the "O" ring inside the valve spring washer) and then the spring released. In this way, the "O" ring is jammed in the taper below the collets, and prevents oil, which collects in the washer, from seeping through and running down the stem. The original shroud which fits in the upper end of the inner spring acts as an umbrella to prevent other oil from splashing in and going down the guide.

Cheers,
Bob
R L Schapel

Agreed, I'm with the original 'O' ring troop--
Another little trick is to chamfer or dome the top of the guide if it's flat on top, I've even seen some new ones that were slightly concave on top and would have acted like a funnel if left like that---
William Revit

This thread was discussed between 17/04/2020 and 21/04/2020

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