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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 - Washer - Manifold Clamp

Is a washer used between the nut (#66) and the manifold clamp (#65) on the manifold stud (#47) of an XPAG/XPEG? Flat washer? Split washer? No washer?

>> The TD and TF Service Parts Lists do not show any washers under the nuts.

Thanks,

Lonnie
TF681
TF7211

LM Cook

I believe they are split washers. That's what I've always seen, and always used.
Steve Simmons

Interesting, Lonnie - on checking, my professionally-built TD engine has no washer, and I know that with my own rebuild of a YA, there was no way, even with slightly longer than original manifold studs, of adding in a washer. Not ideal. It'll be interesting to hear from others. John.
J P Hall

My 1500 has longer studs fitted and a heat shield and I use a spring washer under the nuts to retain tension.
M Hyde

From the web:

This year a NASA manual published in the 1990’s was distributed online in which the actual rocket scientists studied this exact problem and the conclusion that the split washer was all but useless. We’ve all been using split washers for years. I myself was particularly religious about ensuring that my own shell and my team’s boats ALWAYS used 2 flat washers AND a split washer (or lock washer to some). The objective of the lock washer (in our minds) was that this would ensure that the nut remained tightened and did not break lose. The problem, as NASA explains clearly, is that the split washer is essentially useless at this task and in fact that their is NO scientific evidence to suggest that the use of split washers provides any amount of increased friction or locking effect for nuts that would prevent them from loosening. See the study right here:

NASA Study on Fastener Design

Regards, Tom
tm peterson

Interesting. No link to the study? In my personal experience, they do help, depending on the type and hardness of the metal/nut. Many times when a nut is removed with a split washer, there is a big gouge in the nut or mating face. Obviously the sharp edge of the washer dug in and prevented any spontaneous loosening. This may not apply with really hard metal faces and nuts however. The MG factory used them pretty much everywhere on the cars, except on the engine, so they must have felt they helped. I personally would use them on the manifold studs, due to the extreme amount of vibration likely exerted. George
George Butz III

Steve - Thanks. I've always used flat washers ... for no special reason. I installed the manifolds yesterday with flat washers, before I posted my question. Gotta decide whether to replace with split washers. Wonder if no washers on the TF Parts List diagram was an oversite.

Tom - Thanks for the NASA info

George - Here is the link to the NASA Study on Fastener Design:
https://ntrs.nasa.gov/api/citations/19900009424/downloads/19900009424.pdf

I saved it to my "MG Fastener" folder on my computer. Interesting, well-documented info. Download the file to use the bookmarks.

Lonnie
TF681
TF7211
LM Cook

Very interesting. Split washers come in different metals and degrees of compression needed. I prefer the ones used my old Porsche 356. They are the "wavy" type of hardened steel washer. They do add resistance.
M Hyde

This thread was discussed between 13/12/2023 and 16/12/2023

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