Oil Pump working TOO well?

After rebuilding the engine over the winter, I fired it up today; sounds awesome. New valves, guides and rings when really, it may have only needed head bolts re-torque. The reason for the rebuild was excessive smoke on start up.

The new issue is this; I ran it today with the exhaust rocker covers off and saw a steady stream of oil coming form the right side exhaust rocker spindle, collecting in a rather significant pool around the right side exhaust spring. It drains fairly quickly once the engine is stopped (down the push rod tube, I assume) but there was more oil there than I was expecting. Oil pump is certainly doing its job but I'm concerned about excessive oil flow to the head.

Cool day today using 20W50. The lines from the pump to the head are 1/4" (same as fuel lines).

Is this accumulation of oil inside the head normal? Should I reduce the feed tube diameter? Higher/lesser viscosity oil? Will the exhaust rocker cover gaskets hold if on an extended ride?

My main concern is that the exhaust rocker gaskets will start to leak down onto the pipes (messy). Maybe I'm being to picky.

Any thoughts or advise gratefully received. :arrow:

BC
71 Commando
68 TR6P

Check your rocker spindle orientation, the exit hole for the oil should point away from the head inlet hole, if it points towards it there is no restriction and you get excessive oil flow.

Also the tolerance of the spindle to rocker may be on the sloppy side. Hopefully you'll just need to rotate it 180. You are right to think too much oil can be a bad thing up there.

Changing the line diameter will not help. This is the high pressure side of the system and this excessive flow from the spindle/rocker relationship will reduce the pressure to other vital areas in the loop.

The spindle may show an obvious ridge but the rocker less so. These spindles cost much less than a rockers, but If I know these members, someone will help you out for sure. People will "pay it forward" and have sent me things for no charge when in need.

Anyway, this needs to be corrected

kommando said:

Check your rocker spindle orientation, the exit hole for the oil should point away from the head inlet hole, if it points towards it there is no restriction and you get excessive oil flow.

Click to expand...

Not too sure I understand this; exit hole on the spindle should be on the opposite side of the spindle to the oil port on the head?

Any way; Pete V provides a solution. I'll turn the spindle so that the oil orifice in the head is partially closed, thereby restricting the flow. I understand this will increase flow into the other parts of the system so it will take some tweaking. Likely leave the right side 1/2 - 3/4 open and the left side fill open. See if that resolves the issue.

Thanks.

BC

Stillreel said:

I'll turn the spindle so that the oil orifice in the head is partially closed, thereby restricting the flow. I understand this will increase flow into the other parts of the system so it will take some tweaking. Likely leave the right side 1/2 - 3/4 open and the left side fill open. See if that resolves the issue.

Thanks.

BC

Click to expand...

NO. You misunderstood. That is not a solution and will not help you. You need to pull the spindle out, see where the hole is oriented. If it is face out from the center of the head, rotate it 180 degrees so it faces to the center of the head.
If you find that the hole is facing the center of the head upon removal, then you need to measure it up along with the rocker ID. There will be more than likely a ridge where it rides on the rocker, usually on top where the pressure from the springs would hold it. There should be .001" clearance.

pete.v said:

Stillreel said:

I'll turn the spindle so that the oil orifice in the head is partially closed, thereby restricting the flow. I understand this will increase flow into the other parts of the system so it will take some tweaking. Likely leave the right side 1/2 - 3/4 open and the left side fill open. See if that resolves the issue.

Thanks.

BC

Click to expand...

NO. You misunderstood. That is not a solution and will not help you. You need to pull the spindle out, see where the hole is oriented. If it is face out from the center of the head, rotate it 180 degrees so it faces to the center of the head.
If you find that the hole is facing the center of the head upon removal, then you need to measure it up along with the rocker ID. There will be more than likely a ridge where it rides on the rocker, usually on top where the pressure from the springs would hold it. There should be .001" clearance.

Click to expand...

CAREFUL
ON high pressure rocker feed Nortons (1966+) I put my rocker shaft flat/hole to point toward the valve and NOT the push rods. Observe figure C7 in the commando shop manual.
If assembled correctly the main problem for over oil is worn rocker shaft or rocker or both NG.

pete.v said:

Stillreel said:

I'll turn the spindle so that the oil orifice in the head is partially closed, thereby restricting the flow. I understand this will increase flow into the other parts of the system so it will take some tweaking. Likely leave the right side 1/2 - 3/4 open and the left side fill open. See if that resolves the issue.

Thanks.

BC

Click to expand...

NO. You misunderstood. That is not a solution and will not help you. You need to pull the spindle out, see where the hole is oriented. If it is face out from the center of the head, rotate it 180 degrees so it faces to the center of the head.
If you find that the hole is facing the center of the head upon removal, then you need to measure it up along with the rocker ID. There will be more than likely a ridge where it rides on the rocker, usually on top where the pressure from the springs would hold it. There should be .001" clearance.

Click to expand...

Roger that. However the hole in the spindle is correctly oriented. Also the clearances were acceptable between spindle & rockers: no ridge on any spindle either. This still leaves me with too much oil flow. Another thread discussed why the tabs on the inner spindle cover plates would offset the spindle across the oil orifice within the head. It now appears this may have been deliberately engineered to cut the flow.

When speaking of high pressure it usually has low flow. Low pressure, high flow. So, when obstructing or partially blocking orifices, it's kind of a moot point when dealing with a high pressure circuit.

And yes, as Dave has corrected, the flats, with the hole, faces away from the center.

Here's the thread on tweaking the orientation. Some good points

head-and-rocker-spindles-t8159.html

Maybe check your oil pressure. Check for shims in the prv. You might have some stacked up in there.

Stillreel said:

Here's the thread on tweaking the orientation. Some good points

head-and-rocker-spindles-t8159.html

Click to expand...

Reading this thread, Hobot makes an argument for reversing the alignment of the exhaust spindles to allow more oil flow, as the excess oil easily exits the head via the pushrod tunnels.

This would have two big advantages in my thinking:

1. More oil splashing over the exhaust area of the head, taking away more heat.
2. More oil exiting down the pushrod tunnels, whereby it is deposited over the cam and followers.

So, is it a good idea to reverse the spindle orientation on the exhaust side?

Fast Eddie said:

Stillreel said:

Here's the thread on tweaking the orientation. Some good points

head-and-rocker-spindles-t8159.html

Click to expand...

Reading this thread, Hobot makes an argument for reversing the alignment of the exhaust spindles to allow more oil flow, as the excess oil easily exits the head via the pushrod tunnels.

This would have two big advantages in my thinking:

1. More oil splashing over the exhaust area of the head, taking away more heat.
2. More oil exiting down the pushrod tunnels, whereby it is deposited over the cam and followers.

So, is it a good idea to reverse the spindle orientation on the exhaust side?

Click to expand...

Nope. That's not the answer. No shortage of oil splashing about. I'm looking to reduce the oil flow, not increase it (with a nod to Hobit's expertise).

By increasing the flow to the head then you would decrease the flow to the bottom end until the OPRV comes into play.

kommando said:

By increasing the flow to the head then you would decrease the flow to the bottom end until the OPRV comes into play.

Click to expand...

Isn't that the other way around? Decrease flow to the head = increase at bottom end to trigger OPRV?

What I was trying to say is that is that until the pressure comes up enough to trigger the OPRV then if the flow is freer to the head than planned then the flow to the bottom end will suffer. Once the OPRV is triggered then you have 50 PSI at the head and the bottom end. I have done this type of mod to a B44, but that has a roller big end and so does not suffer with the reduced flow as it just needs a feed of oil, a shell big end will.

Got it. I understand.

Thanks all. I'll keep you posted on the results.

BC