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MG TD TF 1500 - Oil feed pipe

Hello,

There are two oil feed pipes listed in the catalogues (B&G, Moss etc.)(taking oil from block to head) for the XPAG... TC/early TD and later TD.

As I am rebuilding my engine at the moment, I have amongst my "spares" three of these feed pipes to select from, but they all look exactly the same, so, and only as a matter of interest, what is the specific difference between an early TD and a later TD one?

My understanding, in the effort to reduce the flow of oil to the head, it was the the upper banjo bolt's internal diameter that was reduced... but happy for any clarification.

regards,

Rhys Alexander
TD 12434
R Alexander

Great timing on this question Rhys.

The early TD used a rubber hose that had a spring around it.

The later TD used an open weave braided line. Exactly the same as the original fuel lines.

I just received a couple of the later lines to rebuild. I have been working to find a way to rebuild the original fuel lines. So far, I have found the inner lining (A wrapped interlocking steel that allows flexibility), but am working on how to separate the outer brass weave from the inner tubing.

Here is a picture of the original rubber/spring line and one of the later lines.

The metal woven lines that are sold today are larger than the original and the weave is tighter. The original had a brass woven cover that was plated (Nickel?)





Bruce Cunha

Rhys
The hoses Bruce refers to are the gauge oil lines not the cyl. head pipes
The cyl head oil supply pipes you are asking about are solid copper tubes
Early TDs had a pipe with identical fittings on both ends, a restrictor for oil supply to the head in the top banjo bolt and a fitting on a banjo bolt for the gauge hose-----

https://mossmotors.com/oil-pipe-head-to-block?assoc=47642

The other pipe that Moss lists has the gauge hose fitting on the side of one of the banjo fittings on the solid pipe instead of on the banjo bolt

https://mossmotors.com/oil-pipe-head-to-block-1?assoc=47643
William Revit

William,

Thanks for that. I had seen the "early TD" pipes, that you have mentioned, in the NTG catalogue where they had been labelled as suitable for a TB/TC so I ruled them out as a TD one.

I just assumed that the oil pressure guage "pick up" came off another part of the engine. Your explanation of a fitting off the the banjo bolt makes sense now.

Thank you,

Rhys.
R Alexander

Thanks for the correction William. I actually did not know there were two head feed pipes.
Bruce Cunha

I think the MAJOR difference between oil pipes is probably difference between the early and late oil pumps. The early pump has an oil filter which is vertical and the later TD pump has a horizontal filter. I'm not sure how the later filter connects to the block except through the pump. I have never had a later style, so my answer may be all wrong.
Lew Palmer

Just to make this all clear
The early pipe--
https://mossmotors.com/oil-pipe-head-to-block^assoc%23%23%2347642

had a banjo bolt fitting for the gauge built into the banjo bolt like this-
https://mossmotors.com/banjo-bolt-w-flex-line-adapt

The later pipe with the op gauge fitting built in--
https://mossmotors.com/oil-pipe-head-to-block-1^assoc%23%23%2347643

and had two plain headed banjo bolts

AND this is where you have to be carefull, whichever setup you have, the banjo bolt with the built in restrictor HAS TO go to the cylinder head to get the gauge to read the actual engine oil pressure correctly
With the restrictor wrongly fitted to the bottom the gauge will only read restricted oil line pressure

willy
William Revit

One minor clarification-

"Early TDs had a pipe with identical fittings on both ends, a restrictor for oil supply to the head in the top banjo bolt and a fitting on 'THE BLOCK' banjo bolt for the gauge hose-----"

When I first read it, someone MIGHT interpret that sentence to say that the bolt with restrictor and fitting were the same banjo bolt, but that isn't the case. If someone stuck the bolt with the gauge fitting at the top, the oil pressure reading would be low.
JIM N

Jim

Early TD's ran the oil line off the head from the factory. I am unsure when this changed (I believe it was early on).

So with that, can you post a picture of what the restricted banjo bolt looks like? It would be good to identify it.

Bruce Cunha

I've heard of that before Bruce
If early TDs had the gauge line onto the top banjo, I wonder if that banjo bolt had the restrictor in the end of it, that would still read full engine oil pressure if like that
I've also heard of a theory that some cars had the gauge fitting at the top and the restrictor in the bottom to stop hydraulic chattering noises coming up into the dash through the oil line---if so the gauge would be reading lower than actual engine oil pressure
willy
William Revit

Sorry about the poor focus. The first image is banjo bolt from head of one of our TDs. It looks just like the Moss photo. There's no restrction in this one but the hole is just a hair smaller than the block banjo bolt.

The second photo shows bolts taken off an engine currently on the stand. I posted a picture of the bolt with restricting orifice AND pressure gauge port a long time ago and was informed that it isn't stock, but a product of someone else's ingenuity and a main jet. That is mounted on the head, while the "head's restricting banjo bolt" is down on the block. I never measured the orifice but can attest the rockers get plenty of oil. Of course the cam gets the drippings so we don't want to choke it down too much.

The only restriction I see with the stock banjo bolts is in the thin oil line, and that isn't much. Unless someone can show evidence of bolts with teeny little holes or a physical restriction, it looks to me like they are a myth. The rockers probably provide all the restriction in reality.





JIM N

Photo of banjo bolt with orifice and gauge installed.

I threw in a picture of the other side of the engine so the Image 2 box wouldn't go to waste.




JIM N

Love the exhaust shroud.

I will check my banjo's but I have not seen any restrictor in any of mine. I will also measure the diameter of the orifice of the oil gauge banjo.
Bruce Cunha

This thread was discussed between 26/06/2021 and 02/07/2021

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