Atlas rocker oil feed line

MikeG · Mar 13, 2020

I have noticed that the rocker feed lines on my project Atlas should be replaced. At present there is a line from the timing chest up to the right hand side and a crossover line to the left. AN shows a single manifold feeding both sides with the line from below attached in the center of it. That seems like a better setup to me really, one less line to deteriorate/leak. Is what I have now incorrect or just different ?

Hortons Norton · Mar 13, 2020

The Atlas head feeds from the top and not the sides like a commando, is that what you have?

Hortons Norton · Mar 13, 2020

I'm working on a bitsa Atlas right now, P.O. was going to turn it into a Triton.

norton bob · Mar 14, 2020

Sounds like a late Atlas system ,same as on my 1966. Side of head feed with loop over head to other side. A Woolwich detail.

possm · Mar 14, 2020

Only a Commando feeds from each side, The Atlas & 650SS Feed from 2 holes on the top, depending on year they could be fed from the return to the oil tank ['65 and earlier] or from the timing chest ['66 and later]

dynodave · Mar 14, 2020

MikeG said:
I have noticed that the rocker feed lines on my project Atlas should be replaced. At present there is a line from the timing chest up to the right hand side and a crossover line to the left. AN shows a single manifold feeding both sides with the line from below attached in the center of it. That seems like a better setup to me really, one less line to deteriorate/leak. Is what I have now incorrect or just different ?

The hydraulic lines whether nylon style fittings or the metal type are functionally NO different, A metal one is with a T between the top or side mount heads. The nylon 11 uses a "pass thru" Y to cross over to feed the opposite side. NO functional difference... The origin of the feed is either high pressure from the timing chest or low/puke pressure from the tank return fitting.
The main hope here is the oil feed style matches the internal high or low pressure rocker shafts.

MikeG · Mar 14, 2020

I should have been more clear. The feed lines are indeed on the top of the head and the feed comes from the high pressure timing chest port. I was really just curious if perhaps the original T metal manifold at the top of the head had been replaced with the Y fitting and crossover nylon tube. Can anyone recommend a good source for new nylon tubing? I replaced the ones on my Commando with SS braided so never really researched it too much.
Thanks

dynodave · Mar 14, 2020

atlas and early commando were metal
nylon was only later commando, but I do use my own nylon fabrications on featherbeds too
MSC or McMaster Carr black nylon 11 is what I have been using since the late 80's

dculgan · Mar 14, 2020

I'm probably wrong about this one too (lol) but for someone relying on the low pressure feed to oil their rocker gear I was concerned that the crossover style nylon Commando set up would tend to favor one side over the other due to physics fluid flow.

I replaced the cracked copper tubing on my Y pipe assembly and removed the nylon line for this reason on my early 1966 Atlas. Dave

Tornado · Mar 14, 2020

Air brake or pneumatic nylon line is what some here recommended on Commando. I found some locally at Princess Auto (a Canadian version of Harbor Freight in USA). Cost me about $0.05 per foot. Fits on the banjos quite tightly, needing a lot of twisting to work it down the pipe. Has held up very well for 5k miles now.

norton bob · Mar 14, 2020

possm said:
Only a Commando feeds from each side, The Atlas & 650SS Feed from 2 holes on the top, depending on year they could be fed from the return to the oil tank ['65 and earlier] or from the timing chest ['66 and later]

No reason to think our Atlas side feed is Not a factory job. It certainly is one of the last lot

dynodave · Mar 14, 2020

norton bob said:
No reason to think our Atlas side feed is Not a factory job. It certainly is one of the last lot

last atlas 125770
my 125336 is still a top oiler
What is yours?
even some 650 mercury( starting 129147) used commando 06-0380 casting but were still featherbed top oilers...

possm · Mar 14, 2020

I used to own a P11 Ranger 129XXX still had top feed, yet my Feb '69 20M3 130XXX Fastback has side feeds.

Mike40M · Mar 15, 2020

Only thing I could add to this discussion is that my slimline 99 had the original copper top feed pipe. In -68 on a nice curvy road, it began broadsiding in the bends. Thought it was a puncture pulled up at small gas station. No puncture but a very oily rear tyre. Bought a piece of rubber pipe, two jubilee clips and a litre of oil. Fitted the rubber pipe over the cracked pipe and continued my journey. At first at reduced speed until the oil had worn off the tyre. Never replaced that quick fix, as it worked perfect.

lazyeye6 · Mar 15, 2020

Mercury. S/N 129857 (one of the last 25 made). Top oiler.

Bernhard · Mar 15, 2020

MikeG said:
I have noticed that the rocker feed lines on my project Atlas should be replaced. At present there is a line from the timing chest up to the right hand side and a crossover line to the left. AN shows a single manifold feeding both sides with the line from below attached in the center of it. That seems like a better setup to me really, one less line to deteriorate/leak. Is what I have now
incorrect or just different ?

What year is your Atlas? Post mid 1966 had a 6 start oil pump worm (double speed oil pump) and Commando type feed pipes, inaddition flats on rocker spindle, which have to be facing the right way or the head will get flooded with too much oil.

MikeG · Mar 15, 2020

Bike/engine is a 64. I have not been into this engine, nor do I intend to. It was a 1/2 finished project that I'm assembling for someone. At first inspection when I took on the job I thought the engine/trans had been gone through, but it now appears not. I've given the owner the option of trusting whats there or starting from scratch and he says trust so that's what I'm doing. I will replace the oil lines just because it's cheap and one less thing to wonder about.

Bernhard · Mar 15, 2020

MikeG said:
Bike/engine is a 64. I have not been into this engine, nor do I intend to. It was a 1/2 finished project that I'm assembling for someone. At first inspection when I took on the job I thought the engine/trans had been gone through, but it now appears not. I've given the owner the option of trusting whats there or starting from scratch and he says trust so that's what I'm doing. I will replace the oil lines just because it's cheap and one less thing to wonder about.

Originally it would have come with a metal Y or T piece to the head fed by the return oil pipe to the oil tank, and 3 start worm with scrolled rocker shafts. But, since 1964, who knows what previous PO has done to this engine?

pierodn · Mar 16, 2020

Bernhard said:
Originally it would have come with a metal Y piece to the head fed by the return oil pipe to the oil tank, and 3 start worm with scrolled rocker shafts. But, since 1964, who knows what previous PO has done to this engine?

Worked fine the early system from oil tank return?

norton bob · Mar 17, 2020

pierodn said:
Worked fine the early system from oil tank return?

Sometimes. I think the pattern of use made a difference. Bikes used for short distance possibly did not warm up fully and did not get enough oil , sludgy oil would block the small low pressure oilways.Looking into the exhaust valve areas ,it was often dry compared to the inlet side. Rockers could tighten on the spindles and make them turn and wear the supports. A little "tuning" of the bias at the tank union can fix this. Too little oil= wear and noise,too much oil =smoky exhaust,sooty plugs,burnt valves. A bit of a balancing act. But I have done it.

Atlas rocker oil feed line

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