Wierd oil leak help

[lillygunny]

My RGS engine has been rebuilt and included a roller bearing conversion and installation of an oil filter. Builder told me not to hook up oil filter until I had 100 miles on the bike-I know, I know, just following instructions. Drained oil from tank and sump, new oil added, oil lines hooked up with return line to filter IN and filter OUT line to oil tank. Started engine, have excellent return flow of oil in tank but LOTS of oil coming between primary and crankcase. Since rebuild, still wet sumps as always and if I don't drain sump would get oil leaking from primary drain (open due to belt drive conversion), so I assume this means crankshaft main seal leak. So is this major oil leak from the main seal or breather? Why did the oil filter hook-up cause the massive increase?

[duTch]

 As you say,  it may be coming from the crank main seal,  but probs more likely from the breather vent under the camshaft bush housing

[a10 gf]

First thought, have a chat with the person in charge of the rebuild, a freshly rebuilt engine should definitely not be delivered with extra 'features' like wetsump + oil leak.

[Black Sheep]

Bypass the filter. Does the leak stop? If so, the filter is the problem.

[Ted_Flash]

If you're using a standard motor car cartridge filter you need to break open the non-return valve - ie the rubber flap on the outside of the filter element.  This will reduce the back-pressure. I've never not done that so haven't seen the effect on leakage.

[bsa-bill]

If you're using a standard motor car cartridge filter you need to break open the non-return valve

News to me Ted, I've two Flash's with filters and had no problems

[Swarfcut]

  I am wondering whether the leak was there from the start, as an assembly fault, but only increased after fitting the filter. If the filter was fitted in the return line to the tank after the feed to the rockers, any restriction by the filter will tend to send more oil back to the crankcase via the rocker feed, and this oil will continue to build up. Simply removing the filter element will eliminate this factor.  Any oil accumulating in the sump will tend to increase the crankcase pressure and this may have displaced the crank seal.  I always use two circular gaskets, one each side, to seal the spacer between the crankcase and the primary inner case. As long as there are no missing bolts or other holes between the case and the crankcase, the primary should remain dry.

  All these should be in order on a newly rebuilt motor. The leak may actually be a consequence of some assembly fault, introducing too much oil into the crankcase, or a failure to scavenge correctly. Plus any aspect of the breather assembly which prevent its correct operation. If it runs ok with a tappet cover off, suspect the breather.

  Swarfy

[JulianS]

Presuming the roller conversion is SRM type and includes end feed conversion also, I would check the oil seal for the end feed at the timing cover. A worn or damaged seal can allow build up of oil in the sump - how do I know? Had the problem and found a split seal. New seal fitted no more problem.

[duTch]

 Swarfo, two things; I'd have thought the rocker oil feed take-off would be just before the tank and after the filter (I know mine is and the rocker have freshly filtered cofffe OIL  )...lilly's may be different.
 The way I see it, the gaskets behind the P-case spacer has no relation to the engine oil, and is only keep oil in the P-case (and water/out), but this case is running dry anyway....., but maybe one of the inner P-case bolts is missing or loose....

[bsa-bill]

have excellent return flow of oil in tank

If oil is returning to the tank as above then the filter is not restricting, btw oil should return to the tank with air included in it ( return side of the pump having more capacity then the feed side).
Breather behind the crankcase (close to the PC) is a obvious suspect, would agree tho that  this should not be the case with a newly built engine, Jullian's remarks make sense

[RichardL]

First thought, have a chat with the person in charge of the rebuild, a freshly rebuilt engine should definitely not be delivered with extra 'features' like wetsump + oil leak.

I looked around to see that you used a shop in South Carolina. If it's who I think it is I'm not surprised by trouble and can understand why you're not communicating with them. My experience would title that particular shop as "worst communicators in the world." You can PM me.

Richard L.

[Swarfcut]

 G'day DuTch..  Yes on both points. The rocker feed should be last in the line to the tank,  as you rightly observe.  The circular gasket has no function as a seal between primary and crankcase, other than to contain the primary oil. So right again. I just like to have a belt and braces attitude to any joint that can leak. Sod's Law says that if it can possibly happen it will. Murphy's Corrollory states that Sod's Law occurs at the most inconvenient moment.   So they say.

  So, maybe JulianS has the answer here. Also easy to check all bolts into the crankcase are present and sealed tight and that the oilseal is in place and running on the correct circular spacer behind the primary drive sleeve and the bearing inner race.

 Swarfy.

[lillygunny]

After talking with Jake Hall (HCV Motorsports) I have fixed the problem. The builder put a Framm 1394 filter in and I replaced it with a Hiflofiltro 147. Problem fixed, so the Framm must have the “flap” inside, which I honestly couldn’t figure out how to remove. Richard,  I appreciate your comments. There is more unfortunately!

[bsa-bill]

which I honestly couldn’t figure out how to remove

Yes you need a filter for certain vehicles, Citroen C5 was one of them as I recall, however a quick test is to put the filter in and blow through it, if you can then it's fine

[chaterlea25]

Hi All,
Not fitting a filter for the first hundred miles is the weirdest notion I have ever heard of 
The majority of metallic particles will "wear" from the cylinder and rings during the initial running and need to be "caught" in a filter
or preferably by a magnetic sump plug before it gets to the pump itself
I have not had problems with any of the random filters I have fitted, I usually fit a 16 to 20mm threaded adaptor to the filter head
and grab a filter from the local motor factors 

John