Oil feed, pressure gauge and threads

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Berticus

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I am rebuilding my 850 engine after an episode with a broken con rod. The rocker oil feed lines are looking a bit tatty and I thought about replacing them but then had an idea about making up my own. I could also connect up a pressure gauge to check the oil pressure. I still don't know why the con rod snapped - I don't think it was a lack of oil but I'd like the reassurance when it is running. Anyway, the point is if I use a double banjo bolt I could temporarily connect a pressure gauge. I don't really want to permanently fit it. Anyway, I'm not very good at identifying threads so could anyone tell me what are the standard banjo bolt thread sizes and is there a supplier of suitable bolts, hoses and connectors that I can make up myself? I could make up a new hose for the front brake to match at the same time if anyone knows the connections I need for that as well. Thanks.
 
The threads for the banjo bolts are 5/16" at 22tpi. You could run a single oil line to the right side of the head, drill the intake rocker shafts and put the pressure gauge on the left side of the head either temporarrily and block the hole with a suitable plug or permanently. I wonder if a small oil pressure gauge could be screwed in that hole :?: There are some kits to mount the gauge on the handlebars, they would fit right in.

Jean
 
I think any good hose place should have what you need. You can buy all the fittings, bolts, banjos ferrals and hose to make your own from oldbritts.com Or have what you want made. They also have a nice oil pressure Gage set up if you want.
 
You can also use the old banjos with the nylon hose, if that is what you have now. Get some Nylon 11 in the correct size, hold the pipe with a flaring tool and beat the banjo fitting back into the pipe with a rubber or hide mallet, WITHOUT HEAT. Believe me, I have done it upon the recommendation of DynoDave. The line is also known as diesel air brake line. The only place I have found it is at MSC, but am told some NAPA stores carry it. It is quite inexpensive and you don't need any hose clamps. However if you want stainless lines, it only comes in black and clear.

Dave
69S
 
I have two questions for DogT. What is nylon 11 and what does MSC stand for? I would like to try this idea but don't understand what those two references are too. Thanks.
 
Here is a simple method of running an oil pressure gage. The only additional plumbing required was a T fitting, another foot of tubing and the gage fitting that probably came with the gage. The yellow line was an air hose that was very hard and difficult to slip over the fittings and thicker than stock. You can see the T fitting above the ground strap on the head steady. It went straight to the gage from the pump and the other outlet went to the right side double banjo on the head. The other end of the double banjo came back across to the left side rocker feed just as is stock. This allowed routing the feed between the carbs and more centrally which I also preferred. I kept a close eye on the line for the 1st while and eventually forgot about it. It has lasted 30 years although the last 25 have been storage but it was still full of oil. This line had ID markings printed on the outside when new but there is no trace of them now.

Oil feed, pressure gauge and threads
 
Jeandr said:
The threads for the banjo bolts are 5/16" at 22tpi. You could run a single oil line to the right side of the head, drill the intake rocker shafts and put the pressure gauge on the left side of the head either temporarrily and block the hole with a suitable plug or permanently. I wonder if a small oil pressure gauge could be screwed in that hole :?: There are some kits to mount the gauge on the handlebars, they would fit right in.

Jean
Click to expand...


Jean,
I did that on my bike last winter. Only one oil line up to the right hand side of the head. Fitted an oil pressure switch (from a car) on the left side . Removed the small switch in the headlight and fitted a warning light there. Connected the light to the switch. Works and looks fine :D

/Per
 
Thanks, I think I will try making up some new nylon pipes. I'm still not decided about permanently fitting a pressure gauge yet. If I can find a double length banjo bolt I will make up a seperate line that I can disconnect. Fitting a gauge is a good idea but I'd rather lash something up temporarily to reassure me that I can get it back on the road and then think about longer term improvements later.

Ludwig, do you know anywhere local I could get some tubing? I haven't had a lot of joy searching the Internet.
 
Per G, What kind of oil pressure switch did you use? I wanted to do the same but was worried it would be lit to often as the pressure gets low at idle. Thanks, Chuck.
 
According the technical description on the website for the "RECTULASTIC" nylon 12 hoses the working pressure drops off very steeply after 20 degees C and is down to 2 bar at 70 degrees. Is this good enough? I thought the oil temperature was somewhere up around 100 degrees C.
 
Use the proper diameter, truck, air brake, nylon tubing. I'm not at home to check the markings at the moment but it IS the ticket. Tony
 
Parker NB-4-062 is an N series nylon tubing with a id of .125" and an of of approximately .25" (which is the od of my stock lines on a 1973 850). The burst pressures are 2000 psi @ 73F and working pressure of 500 psi @ 73F. Will this fit the barbettes on the rocker oil feed banjos? I've read here in the past that some say they will fit if heated first....another posted that they must be fitted cold in order to assure they don't loosen? I sure don't want to spend $100+ on this oil line when there are other parts I need.
 
Parker NB-4-062 is an N series nylon tubing with a id of .125" and an of of approximately .25" (which is the od of my stock lines on a 1973 850). The burst pressures are 2000 psi @ 73F and working pressure of 500 psi @ 73F. Will this fit the barbettes on the rocker oil feed banjos? I've read here in the past that some say they will fit if heated first....another posted that they must be fitted cold in order to assure they don't loosen? I sure don't want to spend $100+ on this oil line when there are other parts I need.
 
How many lines will 100 feet of tubing make? At least 10 (with a lot of waste). Recycle the banjo fittings. Total cost is less than $3 each.
http://www.anythingtruck.com/commercial/airb_hose.html

As I said before, a diesel mechanic friend of mine saves the scrap for me and I have some lines on my bikes that are over 15 years old. I used a heat gun as I had no luck forcing it over the barb cold. No failures.

No question braided stainless is the final answer, but if you consider the cost difference. You could make a new line every year and still be ahead.

my $0.02
 
I was told by a NORTON dealer back in the 70s to put tubing in boiling water get bango started then put both back in and push it on After it cools blow water out of line Phil
 
Ron,

Thanks for that link, I think MSC will sell it cut in 10' sections for about .42/foot which is about double the price for 100'. I don't know if they have a minimum order or what the shipping cost would be, but it shouldn't be much. I'll find out when I try to order some. I didn't have any problem driving the banjo into my old pipe with the flaring tool and a rubber mallet. I tried holding it in my hand and it is impossible that way. I am sure Ludwig's method of drilling a hole in some wood and cutting it in half would work too. I did find you had to be very careful to drive it into the pipe exactly straight. Personally, I would be reticent about using any heat because I can get the banjos in without it and they are very tight, but if you haven't had any problems, great. I know when I took them apart with heat, the pipe was ruined.

Oil feed, pressure gauge and threads


Dave
69S
 
Hortons Norton said:
Per G, What kind of oil pressure switch did you use? I wanted to do the same but was worried it would be lit to often as the pressure gets low at idle. Thanks, Chuck.
Click to expand...

Chuck,
I assume there are many pressure switches that can be used but I use a switch that is listed to fit older Audi 100 1.8 (and many others).
The make of my switch is KW. There are several numbers listed on the box:
Oil pressure switch 500 008
8 012510 137451
Bosch 0 344 101 082
LUCAS SOB 507 (it is actually listed as SOB :D )

I cut a new thread to fit it to the existing threads in the cylinder head.

I can't recall the pressure figure for the swith but it does not go on even on very low idle. Actually goes off at a got push at the kick :D
The oil pump is restored to "better than new" condition and the cylinder head is also fixed so I guess this helps to keep the oil pressure good.

Best regards,
Per
 
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