Topica Loopframe_Guzzi Archive


Subject: RE: Oil Filter for a loop

Author: Greg Bender

Date: Jan 12, 2005, 10:38 AM

Post ID: 1718197798



I'm glad you are bringing up these issues, Patrick. It helps me - for
one - learn a lot. Thanks!

Hmmm...as I'm reading the text and looking at the diagrams in Guzziology
(section 5-11), it appears that filtered Guzzis work as follows (all
except those with external oil coolers):

1. Oil is picked up from the screen in the pan.
2. Oil is sucked into the oil pump.
3. Oil is pushed from the oil pump into the oil filter via the center
hole in the oil filter.
4. Oil goes from the ouside holes of the oil filter to various parts of
the engine.

It also appears that Guzzi's have a pressure relief valve through which
oil passes either before or after it has lubed the rear main and cam
bearings ('before' for filtered models, 'after' for non-filtered
models). The purpose of the pressure relief valve is to make sure the
oil pressure doesn't get too high, as would be the case with cold, thick
oil.

It doesn't appear that there is a oil bypass valve apart from whatever
is built into the filter. Is this really correct?

So...
If the stock design oil bypass valve occurs in the filter on the 'push'
side of the oil pump,

Then this new design would need to have the oil bypass valve in the
filter on the 'pull/suck' side of the oil pump.

It wouldn't seem to matter whether the oil pump is pulling or pushing
oil through the filter, but perhaps I'm missing something here.

In the end, careful planning would need to go into the design of this
new filter so it would suck oil through the filter under the appropriate
conditions, but then also bypass the filter when necessary. Perhaps the
specifics could be gleaned from studying the pressure under which the
UFI filter bypasses?

I haven't heard back from the folks in Germany who created this filter
system, but it would sure be nice to ask them some of these questions.


peha-@comcast.net wrote:
 
Greg: Most oil bypass valves are on the pressure side or downstream of
the pump. The bypass opens and oil flows to the engine without
filtration. At least you have oil. The device we are discussing has
the filter on the SUCTION side of the pump. I doubt there is any way to
create a bypass for filter clogging.

Mind you, this is all speculation. This guy designed it and it may
work, provided you keep the oil and filter changed religiously. I have
no direct information. I only wonder about the design.

Patrick


 Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
Show your pride with a free* USA T-shirt. Click here to confirm
your address.
http://click.topica.com/caac2N5b1dfltb1o6faa/PermissionData
-------------------------------------------------------------------

Hi Patrick,

Good thoughts you have here. If I'm understanding you correctly, you see

the main problem with this unit as the lack of an oil bypass. That is
problematic and something that would need to be addressed as the engine
cannot be starved of oil.

But I'm still interested in this overall design because it would be very

easy to install and wouldn't require new front main bearings or a
different oil pan, plus all the machining that needs to be done with
Dave Richardson's approach. If an engine were disassembled, Dave's
approach would probably be the preferred one. But on an assembled and
running engine, it would be nice to have a bolt on fix.

I'm not sure which type of oil (dyno or synthetic) he recommends nor the

change interval. If an oil bypass was installed, then I don't think it
would matter which type of oil was used. Without an oil bypass, however,

I would think that synthetic would be preferred simply because it is
thinner when cold and would probably pass through the filter medium
better. As for change interval, I *think* the first filtered models
recommended 3,000 mile oil changes and 9,000 mile filter changes (every
third oil change). My 2000 Quota recommends synthetic oil and filter
change every 6,000 miles.

I think there is probably a range of acceptable miles for the oil/filter

changes. I personally like the 6,000 mile interval because it is easy
for me to remember when to change all my fluids (engine, trans, rear
drive)...but there is nothing scientific about that.

Without having the part in hand, it's difficult to know how it might be
altered to provide an oil bypass. If I understand the Guzzi system,
bypass is provided by a spring inside the UFI filter. If I'm wrong,
somebody please correct me. If that's the case, then perhaps the center
bolt that holds the filter on might be designed and machined in such a
way as to provide a spring loaded oil bypass system.

Of course, this all requires designing, machining, and measuring
capabilities that my garage does not have. But, in my opinion, it's an
intriguing idea that holds definite promise.

Patrick Hayes wrote:
 


Greg Bender wrote:
 where they have apparently made an adapter to allow the use of a
non-canister/exposed type oil filter inside the oil pan. This seems very


attractive for obvious reasons (longer between oil changes, maintain

A regular cartridge oil filtration system generally has some sort of
pressure sensing bypass designed in. Either in the filter itself or in
the oil pump and passages. If the oil is too thick, too cold or the
filter is too dirty, the oil supply bypasses the filter and continues to


lubricate vital parts.

The filter proposed here has no such bypass. If you leave it for
"longer duration between changes", you risk having the filter medium
blocked up and the engine starved for oil. How many old loops went
hundreds of thousands of miles without anything but a bug screen to
filter oil? Sounds maybe risky and at least debatable. Wonder how long


he is recommending exchange intervals? And if he is using Dyno or
Synthetic oils?

When Guzzi first came out with the in-pan filter on Tonti frames, I knew


a guy who had moved up from a loop. He decided the filter exchange was
a hassle. He removed one, blew out its guts, and re-installed the
cartridge shell so that it would work like his reliable old loop had
done.

Patrick Hayes
Fremont CA



Regards,

Greg Bender
1971 Ambassador
2000 Quota
http://www.thisoldtractor.com/gtbender

Your free subscription is supported by today's sponsor:
-------------------------------------------------------------------
How about a cruise on your favorite cruise line-from us? Click
here.
http://click.topica.com/caac2NYb1dfltb1o6faf/PermissionData
-------------------------------------------------------------------



Regards,

Greg Bender
1971 Ambassador
2000 Quota
http://www.thisoldtractor.com/gtbender

Entire thread: