Triumph PreUnit oil line supply -to- gauge?

[sprangerny]

I have a 1948 Triumph T5 that has a working oil pressure gauge (I tested with air pressure) but it's not currently hooked up to a supply line. Where should the supply line be attached? Many thanks.48-Triumph-LoRes2-Fla.jpg

[TechNoir]

Hello sprangerny welcome to the forum, I see that this is your first post.

On my 39 both the rocker oil feed and the oil pressure gauge feed come from the front bottom corner of the timing chest. Post WWII the rocker oil feed was moved to the scavenge side of the system but I am pretty sure the oil pressure gauge feed remained in the same place. I had a quick look at some online pictures of late 40's machines sold by Bonhams because they have high resolution images that you can zoom into and the pictures confirm my recollection.

If you google your bike and Bonhams auctions you will see what I mean.

John

[sprangerny]

Many thanks. Most likely this is the feed port you mentioned, where I'm pointing. Will just need to come up with a banjo adaptation, etc. then feed with a hard line up to the oil pressure gauge in the tank. I've seen somewhere that they installed a small rubber hose section between 2 hard lines, to lessen the effects of vibration and cracking of the copper/ss lines. Not sure.T5-Oil-Feed.jpg

[Jim]

Beautiful bike! and you look very happy on it too!

[TechNoir]

Many thanks. Most likely this is the feed port you mentioned, where I'm pointing.

Yes that is where the feed comes from. There is a hollow stud protruding from the case then a banjo retained by a domed nut similar to the domed nuts on the rocker oil feed banjos.

You will see various routings for the pipe in pictures. I think the correct post war routing is similar to pre-war. It comes up the front of the timing chest then across the top of it to the rear of the engine and then up the back of the cylinders and then forward slightly over the rockers and up to the tank gauge.

I am not certain about the rubber bit as my bike is pre-war and therefore all copper.

John

[sprangerny]

John: did you include a picture(s) of those fittings and routing? Didn't see them. Thanks, Doug - photo of the bike without any oil pressure line.IMG_20170824_084940336.jpg

[TechNoir]

The routing on the pre-war pipes is like this. Post war it was just the oil gauge but I believe it was the same route.



The fittings at the engine end are just banjo and a domed nut the same as the rocker feed nuts.

The gauge end will be to suit your gauge.

I assume that your pipe will have a break in just below the tank it as introduced in 1939?

John

[sprangerny]

Many thanks for the photo. Will start to investigate the feed lines to the rockers - and do the detective work from there. The photo is MUCH appreciated!!! Doug

[TechNoir]

I was under the impression that you had a complete bike that was just missing the oil gauge.

However your comments about the rocker oil feed suggest that you have a bike in bits with some parts missing? What other information do you need?

John

[sprangerny]

No, the bike is running and in near original condition. Sorry for any confusion. Only need to plumb-up oil pressure. Was interesting to see the pre-war line configuration. Somewhat different in 1948, where the feed for the rockers comes off a return line nipple - at the base of the oil tank.

[sprangerny]

Here's a photo of the existing return branch, where I can likely install a 'Y', to then feed the gauge - via a separate hard line up to the tank gauge.OilPressLIne.jpg

[sprangerny]

And here's where the rocker lines are currently run.IMG_20171117_104150186.jpg

[TechNoir]

Here is a close up of the stud in the timing cover from a spare that I have. The nut is the same as the rocker nuts. The nut and stud are easily available parts in the UK, given the number of Triumphs sold in the USA I would expect that you can get them easily too.

The gauge end of the feed should use the same fittings as loads of cars such as Jaguar, MG etc. I got my fittings from a Mini spares supplier, they are common and easily available.





Let me know if you need anything else.

John

[sprangerny]

Many Thanks. Invaluable stuff. Will start the 'hunt' for that stud (with by-pass/feed hole) + various fittings required. Last question: do you think the rockers are getting adequate feed by being supplied from the return line branch? Or are they suppose to be fed by the high pressure supply side? They are definitely getting 'oiled', as I cracked the banjos and kicked the bike over - and oil is being fed. But I'm pretty sure that the existing rocker supply lines, etc. are original. Just wondering. Makes sense that the oil pressure GAUGE be supplied by a high pressure, but wasn't sure about the rockers.

[Steve Swan]

John: did you include a picture(s) of those fittings and routing? Didn't see them. Thanks, Doug - photo of the bike without any oil pressure line.[ATTACH=CONFIG]21118[/ATTACH]

Boy. That pre-post WW2 era of Triumph parallel twins has to be the most beautiful of all parallel twins to come out of Merry Old England. The only other marque i would say comes close are the Ariel twins of that era. of course, any of the British machines out of the late 20's until WW2 are pretty much all asthetically stunning.