Oil flow rate

stanfordcg

Junior member
Location
Cambridge
Was looking at installing a oil filter on my 3CL, liked the look of the Morgo kit (http://www.morgo.co.uk/morgo-oil-filter-kit/110-morgo-remote-oil-filter-kit.html)

I asked them if it was sutible for high flow low preasure system, thier reply was "Our filter has a 6 pint flow rate and a non-return valve".

So does anyone know what sort of flow rate the 10mm pump has?
 
I liked the looks of the older filters. Some had problems where the filter would un-screw..the "O" ring would leak slightly there. The new all metal can looks like it eliminates that problem. But you would have to cut it open now..rather than un-thread the top.

Still has the magnet..so should be Okay.

new_magnefine_3_8_s.jpg
 
As long as your oil pump is in reasonable condition, an oil filter will have no significant effect the flow rate. The gear-type oil pump is a positive displacement device which (for a given speed) has a substantially constant flow rate regardless of delivery pressure. Well, within reason at least. It'll probably go up to hundreds of psi, but will eventually stall or shear its woodruff key if the pressure gets too high.

There will be a slight drop in flow as the pressure rises due to increased leakage around the gear impellers, but it's only marginal. The leakage loss will be higher in a worn pump.
 
I have been aware of several triple motors (120 and 180) that have blown up following the fitting of an external oil filter, where no other mods had taken place, speculation comes in here, because I did not have much opportunity to investigate and may not even have seen the damaged bits, but I did have one in my garage and the cause seemed fairly obvious to me, in that the pipework and its various bends and adapters/reducers/converters was causing a massive restriction in the supply of oil to the cylinder base gallery, causing camshaft damage to a big degree, the crankshaft (surprisingly) had survived and the oil for the centre two main bearings comes direct from the cylinder base gallery, but the outers are only splash fed, you would have thought to be able to detect a difference, but I couldn't, it was cam bearings and camshaft that locked up, snapped chain, bent valves damaged pistons crowns, but not sides (pistons are splash fed) Another was a space frame conversion that I didn't get to see in the flesh, but did get sent an online video,plus a phone chat, and I diagnosed blocked oil cooler, and was correct, zero oil going through it, that motor had the semi unusual bleed hole in the oil pipe cast into the inner pri case, to lube the primary chain, and any restriction elsewhere would get "relieved" of flow/pressure by that tiny bleed(er), and I do believe it was more than one blow up before the problem was solved.

My advice is be extremely careful what you do. measure the flow rate through the outlet side of the oil cooler and its relevant hose, using a cordless drill to drive the pump, and when you have fitted your kit, do that again. Make sure you rotate the pump in the correct direction for safety, and don't start me on that one either.

CLEM
 
If using a spin-on filter canister, it would be a good idea to select a filter base that has a pressure relief bypass valve that will still allow oil to flow to the engine if the filter blocks up.

Mind you, if the filter is blocking up with crap, there's something wrong in the engine anyway. There shouldn't be so much sediment getting around inside the engine that it'll block a filter. A blocked filter (or oil cooler) on a blown up engine may be an effect rather than a cause.

Clem's advice to check flow rates is good. As well as confirming good flow, it'll also give an indication of the condition of your oil pump. If there's significantly less flow through the filter than without it, your pump has a lot of clearance around the impellers.
 
you are right Cam, the blocked oil cooler that I talked about was mounted way higher than stock (fairing nose) so the available "pump head" is affected and the extra long hoses were not oil compatible and were breaking down internally.
CLEM
 
I think the filter must be of net or sintered type. Paper filters tend to need a pressure before the filter opens. There must also be no valve which needs pressure loss to open.

Similar issue with fuel lines. Paper filters on fuel lines are after fuel pumps. If there is no fuel pumps, there is also no paper filters. It is possible to try this, add a paper filter between tank and carbs on bike in where is no fuel pump, gravity feed for fuel. On most cases, the fuel comes out from the filter very slowly. I don't say there can't be any exceptions to this.
 
MotoJouni said:
Similar issue with fuel lines. Paper filters on fuel lines are after fuel pumps. If there is no fuel pumps, there is also no paper filters. It is possible to try this, add a paper filter between tank and carbs on bike in where is no fuel pump, gravity feed for fuel. On most cases, the fuel comes out from the filter very slowly. I don't say there can't be any exceptions to this.


Very common to find paper based in-line fuel filters on big (even small) trailies 'back in the day'. Filtration rate is a function of filter area: if gravity feeding then simply install a bigger filter until you achieve the required flow rate characteristics.
 
The oil flow rate  (PSI) is not any more the 1.5 to 3 lbs max - Flow rate is determined by volume (Not PSI). If you can find a pressure gauge to meter a 3 Lb sweep, all the best to yah or just open the top end via a valve adjustment cap and see the oil flow to ensure you got top the end lubricated.

One reason why I tap and drill the cross main gallery to the head with a brass plug to see if it's spitting oil when I pull the plug or put a gauge on on it.

You can place a couple plugs in the main gallery to route, that is by-pass through a cooler, but not necessary (750 SFC's mills did it?).

Basic check to ascertain if your oil pump is working and delivering descent oil volume to the top end.

A metal screen filter with an optional magnetic drain plug using HDEO Diesel DINO Oil 15W40, oil change regularly will work with open mouth Manual Lift Dellorto or Mikuni Carbs.

Expect a Rich Dirty Fuel Stand Off at Idle - It's the nature of a 7500+ RPM 120 Mph 750 Breganzie.

I don't intend to get our 3 Cyl Members upset but the same basic principle applies.
 
AndyW said:
Very common to find paper based in-line fuel filters on big (even small) trailies 'back in the day'. Filtration rate is a function of filter area: if gravity feeding then simply install a bigger filter until you achieve the required flow rate characteristics.

Now I didn't understood what is a trailie. Is it a some sort of bike, tractor, trailer or what it is?  :)
Even my dictionary didn't know what it is. Schools in Finland mostly teach grammar, less to understand the language. I have found many times that people think I understand or speak the language better than I really do.

Can you say bike models which had the paper filter originally on gravity feed fuel line? This would be interesting one for me. I asked this today from a person who officially inspects museum motorcycles in Finland. He could not say any model. In Finland people installed paper filters afterwards to gravity feed fuel lines and often got troubles after that.
 
Motojouni, most of the Finns I've met who remember what they learned in school about English do speak quite good English, but it's English as spoken by people from England. Vince (and Chris and myself) are Australian and speak a quite different version of English, one that uses lots of words you would never have learned in school. Like trailie. And chook chaser.
We do use these words in normal conversation. Fair dinkum.

Ken
 
mcnicol said:
Motojouni, most of the Finns I've met who remember what they learned in school about English do speak quite good English, but it's English as spoken by people from England. Vince (and Chris and myself) are Australian and speak a quite different version of English, one that uses lots of words you would never have learned in school. Like trailie. And chook chaser.
We do use these words in normal conversation. Fair dinkum.

Ken

Absolutely. And when I was in school, some years they teached British English and some years American English. I honestly think I was not able to speak English five years ago. Sometimes I have said things a little bit differently on this forum than I really ment or little bit misunderstood what was actually said. And then the whole conversation goes somewhere very far away from what I actually tried to say. I have also catched myself using some finnish phrases directly translated, those have actually very different meaning in Finnish.




 
Paul Marx said:
Why should anyone want a filter?
Paul

I think the reason is that the only filterings are that "squirrel separator" (finnish spoken language) before the oil pump and centrifugal separators on the crankshaft (and these are at the side circulation, all oil doesn't go through them).

The twin manual said that the oil must be changed after every 2500 km and on triples after every 3500 km (these for Breganzies). At least one reason to this short interval is to get the particles out from the oil circulation.

I have also a drain plug with strong magnet, but it catches only particles of steel, not even stainless steel. The magnet works mostly only as indicator, there is something wrong for sure if it catched more than just few particles after the running-in period.
 
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