Oil line size question

Hi guys,

I'm replacing the oil lines and adding an oil filter kit to my '70 Roadster. Problem I'm running into is with the oil line sizes - the Andover kit gives you 3/8 inch lines to go with the filter unit but the male ends on my banjos and the junction block want bigger diameter hoses. I'd rather not have to buy new male ends, can I use a heat gun or is there some trick to getting the 3/8 inch hose on without compromising it? Can you pick up a larger diameter hose and still get it to clamp onto the filter unit?

Thanks guys!

David B

Which banjos are you referring to?

Other than the small rocker feed line banjos, the only other one I can see is the large one at the rear of the oil tank and the hose to that is exactly the same size as the rest of the lines to and from the filter and the oil pipes on the engine behind the timing cover.

Danno said:

Which banjos are you referring to?

Other than the small rocker feed line banjos, the only other one I can see is the large one at the rear of the oil tank and the hose to that is exactly the same size as the rest of the lines to and from the filter and the oil pipes on the engine behind the timing cover.

Click to expand...

It's a '70 Roadster, so I expect he means the two central oil tank banjos.

L.A.B. said:

Danno said:

Which banjos are you referring to?

Other than the small rocker feed line banjos, the only other one I can see is the large one at the rear of the oil tank and the hose to that is exactly the same size as the rest of the lines to and from the filter and the oil pipes on the engine behind the timing cover.

Click to expand...

It's a '70 Roadster, so I expect he means the two central oil tank banjos.

Click to expand...

OB shows a filter conversion kit for 69-70 Commandos. A buyer would assume the kit is all-up as-is, but?

That being said, a larger hose can be sleeved down with a short piece of small hose, but if it's a pressurized line, I would do something to bond the inside piece to the larger hose. many times a smaller hose can be heated and adapted to a larger fitting with some judicious heat application and a good shove.

Danno said:

OB shows a filter conversion kit for 69-70 Commandos. A buyer would assume the kit is all-up as-is, but?

Click to expand...

The OB "Oil Filter Conversion Kit" listed in '68 -'70, Group 48, is the NV factory 064283 kit for '71 - '72 Commandos, although it can be adapted to fit earlier models, neither OB or AN makes that clear, unfortunately.

http://www.oldbritts.com/13_064283.html
https://andover-norton.co.uk/en/shop-details/16306

L.A.B. said:

Danno said:

Which banjos are you referring to?

Other than the small rocker feed line banjos, the only other one I can see is the large one at the rear of the oil tank and the hose to that is exactly the same size as the rest of the lines to and from the filter and the oil pipes on the engine behind the timing cover.

Click to expand...

It's a '70 Roadster, so I expect he means the two central oil tank banjos.

Click to expand...

Yep, it's the central oil tank banjos.

I think the nipples on the junction block are just soldered on.
After removal from the engine a propane torch could be used to remove them and you would then have the 3/8" pipe.

The banjo is a bit closer to the camera so the size difference isn't quite as much as it appears in the photos but this gives an idea as to the size difference in the male ends:

Danno said:

L.A.B. said:

Danno said:

Which banjos are you referring to?

Other than the small rocker feed line banjos, the only other one I can see is the large one at the rear of the oil tank and the hose to that is exactly the same size as the rest of the lines to and from the filter and the oil pipes on the engine behind the timing cover.

Click to expand...

It's a '70 Roadster, so I expect he means the two central oil tank banjos.

Click to expand...

OB shows a filter conversion kit for 69-70 Commandos. A buyer would assume the kit is all-up as-is, but?

That being said, a larger hose can be sleeved down with a short piece of small hose, but if it's a pressurized line, I would do something to bond the inside piece to the larger hose. many times a smaller hose can be heated and adapted to a larger fitting with some judicious heat application and a good shove.

Click to expand...

I have the Andover kit. That's what I'll try tonight - get the hose nice and warm and see if I can persuade it on. Wish me luck!

I fitted an oil filter kit to my 1970 Roadster in 2012.
I struck the same problem with the hose size being too small for the banjos and junction block.

As Bob said, the barbed ends on the junction block are soft soldered to the pipes. I removed them, leaving a pipe dia. of approx. 3/8" which the hoses could fit onto.

The banjos are another matter. I think they have 3/8" pipes which are then sleeved up similarly to the junction block but with plain rather than barbed sleeves. They appear to be silver soldered not soft soldered.
Rather than butcher the banjos, I put them away for posterity and made new ones from scratch with 3/8" pipes. Having a lathe is essential for Norton owners.

I forgot to mention previously:

For forcing hoses onto pipes that are too big, I smear some rubber grease on the pipe. I don't usually apply heat as it makes the hose soft and so it collapses as you try to push it.

I also ran into the same problem a while ago. I am pretty sure it was an Andover kit and the hoses in the kit were too small. Also too short, as I recall. I made a couple of inquiries about buying some replacement herringbone pattern hose of the correct and almost fell off my chair when I heard the price. I used the existing hoses where they were visible, and bought some correct diameter hose (non herringbone) for the not visible parts. Fiddly job, cramming all that hose into a very busy space. And especially fiddly if you have to drill the mounting holes in the cradle to mount the filter body. The dimensions for the hole centers provided in the kit are close, but they differ enough from a couple of other Commandos that I have with factory installed filters that I didn't trust them.

Stephen Hill

As an update, I was able to use some 3/8" line from my local Brit bike shop. It was rated for 50 psi instead of 400 psi like the stuff in the Andover kit so it was more flexible and much easier to work with. I was able to get it on the banjos and lines out of the engine. I tried desoldering the barbs from the oil junction block but they weren't budging. I should be in good shape though. Thanks guys!