Oil valve solution to oil falling to crankcase

Here's a side value of the reed breathers...

A forum member (won't embarrass him) put the oil pump gasket on wrong. When he checked for oil returning, he mistook the breather return for the pump return. He rode the bike quite a bit before asking about it. Nothing was hurt (other than pride)! Had he not installed the breather, running would have filled the crankcase with oil and probably resulted in a catastrophic hydrolock.

I agree that reed valve breathers are the best solution for engines without the timed breather .

My new to me '76 Mk III presently has a spring loaded detent ball valve in line. The PO pointed it out and was very positive about it being a cure for wet sumping. I knew virtually nothing about the subject, but when it was explained the oil passes through your oil pump to create the "wet sump", I questioned how you could know the oil pump is primed at start to open the check ball?

It may be that the oil pump does somehow keep a prime at all times including after sitting unused for long periods of time, but I was not comfortable with having my oil line blocked until the pump can provide sufficient pressure to open the valve. Maybe it's not a problem, but I am choosing not to risk it, and removing the valve from my line.

Having read this thread, and some others, I have ordered the NYC Norton Reed Valve. It is first mentioned on page two of this thread and immediately impressed me as the best "big picture" solution.

I have found many of the posts to be intriguing, and not to suck up, but I found L.A.B's post # 230 to be pivotal. Rather than fight the oil pump, let it be, and use a Reed Valve. One can be made more affordably than buying a kit, but I believe I will get a well thought out, quality design with the NYC unit, and theses days, the cost is not that great. The other one looked good too, but I just chose NYC. BTW, it is free shipping...

Edfury828 said:

My new to me '76 Mk III presently has a spring loaded detent ball valve in line. The PO pointed it out and was very positive about it being a cure for wet sumping. I knew virtually nothing about the subject, but when it was explained the oil passes through your oil pump to create the "wet sump", I questioned how you could know the oil pump is primed at start to open the check ball?

It may be that the oil pump does somehow keep a prime at all times including after sitting unused for long periods of time, but I was not comfortable with having my oil line blocked until the pump can provide sufficient pressure to open the valve. Maybe it's not a problem, but I am choosing not to risk it, and removing the valve from my line.

Having read this thread, and some others, I have ordered the NYC Norton Reed Valve. It is first mentioned on page two of this thread and immediately impressed me as the best "big picture" solution.

I have found many of the posts to be intriguing, and not to suck up, but I found L.A.B's post # 230 to be pivotal. Rather than fight the oil pump, let it be, and use a Reed Valve. One can be made more affordably than buying a kit, but I believe I will get a well thought out, quality design with the NYC unit, and theses days, the cost is not that great. The other one looked good too, but I just chose NYC. BTW, it is free shipping...

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Pleased you see value in this post and value in the NYC reed valve...they work great....I see no value in a possible restriction accessory as pictured

Edfury828 said:

My new to me '76 Mk III presently has a spring loaded detent ball valve in line. The PO pointed it out and was very positive about it being a cure for wet sumping. I knew virtually nothing about the subject, but when it was explained the oil passes through your oil pump to create the "wet sump", I questioned how you could know the oil pump is primed at start to open the check ball?

It may be that the oil pump does somehow keep a prime at all times including after sitting unused for long periods of time, but I was not comfortable with having my oil line blocked until the pump can provide sufficient pressure to open the valve. Maybe it's not a problem, but I am choosing not to risk it, and removing the valve from my line.

Having read this thread, and some others, I have ordered the NYC Norton Reed Valve. It is first mentioned on page two of this thread and immediately impressed me as the best "big picture" solution.

I have found many of the posts to be intriguing, and not to suck up, but I found L.A.B's post # 230 to be pivotal. Rather than fight the oil pump, let it be, and use a Reed Valve. One can be made more affordably than buying a kit, but I believe I will get a well thought out, quality design with the NYC unit, and theses days, the cost is not that great. The other one looked good too, but I just chose NYC. BTW, it is free shipping...

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The inline check valve will stop wet sumping and can also destroy your engine. The oil pump is designed to be primed at all times and the check valve can easily defeat that design. Also, a MK3 has a built-in valve after the pump to stop wet sumping. They don't always do the job, but they don't destroy engines either. I just finished repairing an engine with the exact oil line check valve you have. Luckly the engine did not blow up, but there was bad damage in many areas and it cost him a lot to get it all fixed.

The crankcase reed valves are an excellent addition - they do not stop wet sumping but they help clear it quickly and they reduce crankcase and other engine oil leaks. They will even save you if the return side of the oil pump is not working for some reason. If rebuilding an engine, I use the cNw reed valve. If not and it's and crankcase that can take the screw-in breather, either the JS Motorsports or NYC - both work well.

One more for the reed sump breather and NOT a check valve! Also - apropos my earlier question about the standpipe...thanks for the responses regarding its importance to the proper function of a reed sump breather. As to details about the height of the standpipe; it would seem that the top needs to be slightly above the hole in the "floor" of the cavity in the drive-side case, where oil accumulates, drains, and is then returned. Looking at the difference in standpipes between the CNW and the JS Motorsport versions, there is a notable difference in height - BUT - the bodies are also different heights, and the resulting overall top-to-bottom "working" measurement in the crankcase is essentially the same.

Fast Eddie said:

The tube that sticks up above the screen into the crank case, is there to ensure the oil level is left in the crank case.

Without that tube ALL of the oil would be returned to the tank via the breather, leaving no oil in the cases to be whipped up be the crank and lubricate the cam, pistons, bore, main bearings, etc.

The vast majority of the internals in a Norton engine are fed by splash / mist. The oil pump only feeds the big ends and a tiny dribble to the rockers.

Without that tube, you’d effectively starve a lot of this splash / mist lubrication.

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In my ignorance I half copied the crankcase reed valve idea on my bsa A10
But I didn't use a standpipe
I wanted the reed valve mainly to clear a sump full of oil as the bike is ridden very infrequently
It has an aftermarket deep aluminium sump plate with a drain plug
I attached a hose to the sump plate with an inline reed valve mounted a few inches away between the engine plates
It did indeed clear the sump on start up
But I don't believe it emptied the crankcase completely as the bike ran fine
Maybe that was because the reed valve was higher?
I have since removed it because I damaged the hose with a bike lift
I plan to fit a standpipe to just above the height of scavenge pipe when I refit it

Edfury828 said:

My new to me '76 Mk III presently has a spring loaded detent ball valve in line. The PO pointed it out and was very positive about it being a cure for wet sumping. I knew virtually nothing about the subject, but when it was explained the oil passes through your oil pump to create the "wet sump", I questioned how you could know the oil pump is primed at start to open the check ball?

It may be that the oil pump does somehow keep a prime at all times including after sitting unused for long periods of time, but I was not comfortable with having my oil line blocked until the pump can provide sufficient pressure to open the valve. Maybe it's not a problem, but I am choosing not to risk it, and removing the valve from my line.

Having read this thread, and some others, I have ordered the NYC Norton Reed Valve. It is first mentioned on page two of this thread and immediately impressed me as the best "big picture" solution.

I have found many of the posts to be intriguing, and not to suck up, but I found L.A.B's post # 230 to be pivotal. Rather than fight the oil pump, let it be, and use a Reed Valve. One can be made more affordably than buying a kit, but I believe I will get a well thought out, quality design with the NYC unit, and theses days, the cost is not that great. The other one looked good too, but I just chose NYC. BTW, it is free shipping...

Click to expand...

The oil pump is a positive displacement pump and will draw air until it primes itself.

Edfury828 said:

I questioned how you could know the oil pump is primed at start to open the check ball?

It may be that the oil pump does somehow keep a prime at all times including after sitting unused for long periods of time, but I was not comfortable with having my oil line blocked until the pump can provide sufficient pressure to open the valve. Maybe it's not a problem, but I am choosing not to risk it, and removing the valve from my line.

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There is no way to tell with an inline check valve if oil is flowing through the engine at startup. After running a while if oil is returning to the tank then it is flowing in. That is usually quick, but have it be delayed from time-to-time and you do damage. The engine I just fixed required four rocker spindles, two rockers, big end shells, main bearings, a camshaft, re-ground tappets, and luckily only crankshaft journal polishing (they were just in spec once polished). Terrible for a bike with 8k miles! I have no doubt that the valve eventually opened on each ride but eventually is WAY too long.

You might stay primed if your built-in valve is working. Importantly, you're doing the right thing and getting rid of the check valve. Once done, if you wet sump, then remove the timing cover and figure out why in the off-season.

The reed valve breathers just need their pickup to be somewhere above the oil return line - they can and do remove excess oil, but that is not their job. In other words, the "standpipe" can be longer or shorter (as long as it doesn't hit the crank and is above the oil return pickup) with no problem - not rocket engineering. The cNw breather has no standpipe and is mounted on the outside rear of the crankcase with nothing protruding into the crankcase. That design, IMHO, is better than the sump plug type as it is doing the breathing job and has a lot bigger opening to the crankcase air and many other crankcase oiling changes are machined by cNw. The downside is having to send in the crankcases for machining and the cost. It actually clears a wet sump faster, but not as completely which is unimportant.

Wait! What? "the "standpipe" can be longer or shorter (as long as it doesn't hit the crank and is above the oil return pickup)" ???

The reed breathers for sump plug applications are nowhere near the crank. They screw into a cavity/chamber of their own at the bottom of the drive side case. But, you are right about 'above the oil return pickup' which is a hole in the cavity/chamber above that and behind the crankshaft.

Kip said:

Wait! What? "the "standpipe" can be longer or shorter (as long as it doesn't hit the crank and is above the oil return pickup)" ???

The reed breathers for sump plug applications are nowhere near the crank. They screw into a cavity/chamber of their own at the bottom of the drive side case. But, you are right about 'above the oil return pickup' which is a hole in the cavity/chamber above that and behind the crankshaft.

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If the standpipe were long enough, it would hit the crank! I know exactly where they are and I've had them and the crank in with the other case half off!

My point was that it could be longer or shorter and it will work, it's just a matter of how low it will drain the sump and if too low, the oil return will be starved.

In fact, remove one and you can easily see the crank and touch it with your finger.

That recently saved a guy here because he had a magnet come off the oil plug and thought he had to take the engine apart - we told him to remove the sump plug and turn the engine until the magnet came into view stuck on the flywheel - worked perfectly.

hybridracer said:

I agree that reed valve breathers are the best solution for engines without the timed breather .

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IMHO the reason Norton, Triumph, et. Al. removed the timed breathers is that they were ineffective and a PITA when building/rebuilding an engine. It was also pretty terrible to throw away a crankcase damaged where one got fouled or improperly installed and tore up the crankcase and camshaft bushing.

hi,
Volumes have been written on this. Many install shutoff valves and are very happy with the results
I know you’re trying to do everything correctly and I hope you are rewarded with a superb bike but I urge to to reconsider installing a valve.
At the risk of ’blowing my own trumpet I guess I have to confess to being a something of an expert understanding risk (aviation). No matter what assurances you give yourself or what precautions and safety mechanisms you include, I believe the risk of a catastrophic event is only increased by putting a potential fail point between your engine and the oil that lubricates It. The slight risk of seal damage is outweighed by the very slight risk of oil starvation.
Some may be aware of Prof James Reason’s ‘Swiss Cheese‘ model regarding the trajectory of a disaster but in brief, if something bad can happen, it will happen, almost always as a consequence of a string of a number of seemingly unrelated events. You may choose to call it Murphy’sLaw if you want but it is impossible to fully guard against. To point, trains have the best signalling systems in the world but they occasionally still run into each other.
Yes, wet sumping is an issue with my Mk2 which is not ridden nearly enough but i never rev it on start up, keep it an idle until I see bubbles appearing in the oil return line. Up till now I have had no issues (famous last words) but I would rather confront a blown seal than a seized engine. Draining the oil and returning it to the tank is arguably the gold standard, providing scrupulous cleanliness is maintained.
Many will disagree with me and their opinions are equally as valid as mine
Alan

javifoto70 said:

Thank you everybody! Now I see my colleague was right and I will definitely buy and install an oil tap with cutout switch on my bike before the first kick over. I do not want to take any risk to damage the engine after the many months I will spend restoring the bike. And once the bike will be ready I will use it with pleasure but probably randomly because I own other bikes I also need to attend.

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marshg246 said:

IMHO the reason Norton, Triumph, et. Al. removed the timed breathers is that they were ineffective and a PITA when building/rebuilding an engine. It was also pretty terrible to throw away a crankcase damaged where one got fouled or improperly installed and tore up the crankcase and camshaft bushing.

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marshg246 said:

If the standpipe were long enough, it would hit the crank! I know exactly where they are and I've had them and the crank in with the other case half off!

My point was that it could be longer or shorter and it will work, it's just a matter of how low it will drain the sump and if too low, the oil return will be starved.

In fact, remove one and you can easily see the crank and touch it with your finger.

That recently saved a guy here because he had a magnet come off the oil plug and thought he had to take the engine apart - we told him to remove the sump plug and turn the engine until the magnet came into view stuck on the flywheel - worked perfectly.

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Okay - possible but highly unlikely, way too long if it hits the crank...and if you have pictures of the case half with the breather installed, I'd love to see it. Thanks!

marshg246 said:

IMHO the reason Norton, Triumph, et. Al. removed the timed breathers is that they were ineffective and a PITA when building/rebuilding an engine. It was also pretty terrible to throw away a crankcase damaged where one got fouled or improperly installed and tore up the crankcase and camshaft bushing.

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I agree. Timed breathers have never been great and are usually only effective in a certain narrow rpm range.

Because Reed valves do not prevent an engine from fully wet sumpinng, there can be no oil over the in tank mesh screen. So then likely no oil in pipe upstream of pump, so no pressure feed to crank at start up until pump re-primes and that cannot happen until enough oil has made it back to tank.

I prefer my solution, a ball valve with ignition defeat on feed line. Wet sump completely prevented. No risk of starting without oil feed to pump. Feked in UK sells such a valve with switch for about $80. I made my own for about $10 in hardware store parts and a micro switch.

Curiously, Velocette had a spring loaded ball check valve on the pump feed line on most of their bikes for decades. They use, as far as I can tell, a similar gear pump as our bikes. Some how many are still running fine for 70 years?! I would not use one, but they can be reliable when made right I guess.

Tornado said:

Because Reed valves do not prevent an engine from fully wet sumpinng, there can be no oil over the in tank mesh screen. So then likely no oil in pipe upstream of pump, so no pressure feed to crank at start up until pump re-primes and that cannot happen until enough oil has made it back to tank.

I prefer my solution, a ball valve with ignition defeat on feed line. Wet sump completely prevented. No risk of starting without oil feed to pump. Feked in UK sells such a valve with switch for about $80. I made my own for about $10 in hardware store parts and a micro switch.

Curiously, Velocette had a spring loaded ball check valve on the pump feed line on most of their bikes for decades. They use, as far as I can tell, a similar gear pump as our bikes. Some how many are still running fine for 70 years?! I would not use one, but they can be reliable when made right I guess.

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I agree that a shutoff with fail safe protection would be good. The Feked solution is not fail safe - no micro switch is. I bet you did a good job - that's not to say all would. I'm amazed at the self-inflicted problems I must fix.

Although expensive, I always offer customers a MK3 timing cover or have them send their cover to be modified. Although it does not always work to prevent wet sumping, the valve after the pump is safe.

You are right in your first statement. However, the oil cannot go below the output of the oil tank and the reed valve will pump lots of oil to the tank in a few engine revolutions. It only takes a couple of ounces to add enough oil in the tank to start the feed. Also, a great deal of oil is thrown around in the engine until the sump is cleared. Finally, the crank is generally partly to completely full in a full wet sump so the big ends will be OK. Wet sumping is much less dangerous than a closed valve!

On the Velocette question - I know nothing, but if the check valve is below the oil pump or at least well below the metal oil pump feed pipe, it could do its job without starving the pump - much like plumbing - a trap. I believe that could be done on a Norton to make a check valve safe - but I ain't gonna try er!

Kip said:

Okay - possible but highly unlikely, way too long if it hits the crank...and if you have pictures of the case half with the breather installed, I'd love to see it. Thanks!

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Of course it's unlikely - what dummy would manufacturer and sell one so long that it would hit the crank. If it so hard to understand the point of my statement even after I explained it, I apologize!

Tornado said:

Because Reed valves do not prevent an engine from fully wet sumpinng, there can be no oil over the in tank mesh screen. So then likely no oil in pipe upstream of pump, so no pressure feed to crank at start up until pump re-primes and that cannot happen until enough oil has made it back to tank.

I prefer my solution, a ball valve with ignition defeat on feed line. Wet sump completely prevented. No risk of starting without oil feed to pump. Feked in UK sells such a valve with switch for about $80. I made my own for about $10 in hardware store parts and a micro switch.

Curiously, Velocette had a spring loaded ball check valve on the pump feed line on most of their bikes for decades. They use, as far as I can tell, a similar gear pump as our bikes. Some how many are still running fine for 70 years?! I would not use one, but they can be reliable when made right I guess.

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The Velo spring loaded valve on suction is also what Holland Norton Works sell. Their ball-and-spring tank fitting replaces the stock tank outlet fitting (the one with the screen). The Holland Norton Works one does not have a screen. Their rationale is that all the oil comes back to the tank via the filter. Not so if you have a reed valve.

Kip said:

Okay - possible but highly unlikely, way too long if it hits the crank...and if you have pictures of the case half with the breather installed, I'd love to see it. Thanks!

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?!?

You’re the guy who asked how long the pipe should be !

Greg is simply trying to help you understand the logic behind the extremes of too long and too short.

So actually it is not highly unlikely at all, it is in fact definite that if it’s long enough it will hit the crank !