Oil Pump and Wetsumping

As discussed in the wetsumping thread (does-wet-sumping-cause-any-damage-t2755-30.html) there is talk about oil pumps. Ludwig spotted an interesting oil pump in one of Jim's pictures from a different thread (jim-how-about-them-there-timing-gears-t4679-15.html).



I bet that engine doesn't wetsump...

So the question is what did Jim make and is it feasible to produce?

From: comnoz
To: swooshdave

Sure, 20 years ago I had a couple of camshaft failures in a row. I decided the way to prevent that was to rflle drill the cam and drill a hole in each lobe for better lube. I ran an oil line to the end of the cam from the supply to the head and put a small orfice in it. Then I found that my stock low oil pressure went to zero oil pressure when the bike was hot because of the extra drain on the pump. So I took a piece of hard aluminum and built a new one with new gears .060 wider than stock and tightened up all the clearances to cut down on internal leakage. Now the oil pressure never drops below 40 even at hot idle. Someday when I get there I would like to write a program to make a few copies in the CNC machine.No Carbscomnoz

Posts: 147
Joined: Wed Dec 10, 2008 9:28 pm
Location: Pueblo Co.

Just solve your wetsumping problem by installing a CNW inline valve. First I installed a RGM type valve (aluminium) but lost 5 psi throughout the pressure range. Then I tried the CNW valve and noticed no pressure loss at all. So far I did around 12.000 mls without any (wetsumping)problems on this CNW valve:

nortonspeed said:

Just solve your wetsumping problem by installing a CNW inline valve. First I installed a RGM type valve (aluminium) but lost 5 psi throughout the pressure range. Then I tried the CNW valve and noticed no pressure loss at all. So far I did around 12.000 mls without any (wetsumping)problems on this CNW valve:

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My brother lost an engine due to an inline valve. Don't know the brand or where he got it from. Just makes me nervous thinking about anything that has the potential to block the oil flow. Obviously the CNW valve is going to be top notch.

Tightening up the clearances (either the stock pump or like Jim did) seems to be the correct answer.

I don't have any wet sumping partialy due to the fact that I also machined the timing cover for a fitting at the pump outlet and have a line going from there to the oil filter so the filter is on the pressure side of the pump. There is a rubber flap valve in the filter that prevents the oil from going through the filter when there is no pressure. Jim

I re-surfaced the oil pump as per the Norton shop manual info when I was doing my top end work this past week; I'll be interested to see if the wet-sumping is reduced...

Me too, and I finally just got around to installing the rebuilt oil pump in my 750. I have not done the timing cover mod however. That bike had quite a severe wetsumping problem, so it will be interesting to see if the rebuilt pump helps. I'm looking forward to trying it out in a few months when Spring arrives. :?

Debby

I wonder about those modern super-hard micron layer treatments for the pump gears?

comnoz said:

I don't have any wet sumping partialy due to the fact that I also machined the timing cover for a fitting at the pump outlet and have a line going from there to the oil filter so the filter is on the pressure side of the pump. There is a rubber flap valve in the filter that prevents the oil from going through the filter when there is no pressure. Jim

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Comnoz, your machining of the timingcover for a fitting at the pump outlet sounds very interesting can you be more specific on that point (please)?

Just resurfacing the pump is not the holy grail to stop wet sumping. if there is any wear in the housing at the outer diameter of the gears, there is any wear where the shafts fit or any wear between the gears on the tooth face's GUESS WHAT WILL HAPPEN








wet sumping!!!! as for the valve in the suction line IMHO it is a disaster waiting to happen. just because CNW sells them does not make it a justifiable reason to use one. he also sells barnett clutches and likes them but I would not put one in a tricycle as they are to grabby and too narrow of engagement point. a 5 plate surflex clutch is a far better option IMHO but it takes a little work to fit.

You are right about the leakage around the outside of the gears. And the sad thing is the last new pump I bought [many years ago] had 3 to 4 thousanths clearance around the gears the way it was built. That clearance needs to be well under 1 thousanth if the pump is going to maintain good oil pressure at slow speed and do much as far as slowing the oil migration back to the sump.
I figure some of the new hard coatings could be of some benefit to the pump gears and I have wanted to try some of the thicker coating on the inside of the pump housing to take up some of the extra clearance.

As far as modifying the cover for a fitting I tried to find a picture but didn't find a very good one. What I did was , starting with a mk3 cover I drilled through from the inside at the oil pump hole and tapped the hole for a shortened 1/4 pipe thread 90 degree AN adapter. Then to keep the cross drilling from intersecting the hole I drilled the head feed hole larger past the oil pump and pushed in a thin walled aluminum tube with JB weld. I think I enlarged it to around 21/32. Then I tapped the hole for 1/8 pipe thread as this took out the 5/16 banjo bolt threads. Now the oil coming out of the pump passes around the outside of the tube and comes out the fitting on the side . Then it goes through the filter . I removed the press in fittings from the filter housing and tapped them to 1/8 pipe and installed AN adapters. The outlet of the filter tees into two lines, one to the cylinder head and the other to the fitting that used to be the feed for the head. This line now feeds the crankshaft and the oil pressure relief valve.
In this picture you can see the fitting coming out of the timing cover and going down right behind the brake pedal.

Thanx Comnoz for your explanation :idea:

bill said:

as for the valve in the suction line IMHO it is a disaster waiting to happen. just because CNW sells them does not make it a justifiable reason to use one.

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I use this particular valve not just because CNW sells them but because I compared, tried and measured these valves (with cold oil as well as hot oil) and I am reserved to people like Les Emery telling us it is a disaster waiting to happen just like that.

nortonspeed said:

bill said:

as for the valve in the suction line IMHO it is a disaster waiting to happen. just because CNW sells them does not make it a justifiable reason to use one.

Click to expand...

I use this particular valve not just because CNW sells them but because I compared, tried and measured these valves (with cold oil as well as hot oil) and I am reserved to people like Les Emery telling us it is a disaster waiting to happen just like that.

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I think folks reservation is not that the valve may work (and test well) but that they become a point of failure, and a disastrous one at that.

swooshdave said:

I think folks reservation is not that the valve may work (and test well) but that they become a point of failure, and a disastrous one at that.

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Swooshdave thanx for your concern but I can think of many disastrous points of failure but like I mentioned before I already rode 12.000mls with this CNW valve and before that I rode about 25.000 mls with the RGM valve but I never liked the 5 psi loss throughout the pressure range (especially at idle), that's the reason I changed to the CNW valve. Beware of disastrous velocity stacks :mrgreen:

just because CNW sells them does not make it a justifiable reason to use onete

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Bill,

Important fact is that CNW is not a parts seller like many other companies out there. Our main business is building complete machines as well as engines and we also sell some of the parts that we use in ALL of our builds. We only sell the parts we are willing to stand behind as far as performance and quality. In other words we are not a parts house offering hundreds of different products needing to move volumes in order to make the business operate. We simply decided to offer some of the parts that we stock and develop for our own machines, for those that want to work on their own bikes. As it turns out people really like the idea and the parts section has grown. Then working closely with people like Jim Comstock and Ken at Fullauto, well needless to say, there are some very exciting new products made available due to their efforts.

So what I am getting at is that is not that we just sell the valves....we use them in 100% of the rebuilds we do and we have done so for several years. I am not saying that there arent other opinions out there for what works, but we trust these valves to work and if we didnt we certainly wouldnt take any chances with our machines because of a 70.00 valve.

Whats great is that people have the choice to run with it or not.

BTW Bill.....I dont think Barnett offers a kit for your Tricycle so you couldnt use one even if you wanted to.

Thanks

Matt

comnoz said:

... I tried to find a picture but didn't find a very good one.

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How about these:





You must have better ones of the same from which you can crop the interesting parts. I was really puzzled by the pipes, thanks for the explanation. Now you have opened a bigger can of worms, you must take your bike apart and take pictures as you do :mrgreen:

Jean

I need to get a fresh motor in it before spring gets here so I will take some more pictures. Of course my picture filing system leaves a lot to be desired so finding them could be a problem. Jim

Humm, I wonder if Apple's facial recognition in iphoto works on motorcycle parts...