Hey all,

I was hoping you might be able to shed some light on a problem I have after rebuilding my 1200.

After rebuild I have excessive oil return or relief pressure happening in the oil system. The tank overflows even when run at low oil level.

Signs are:
Over-flow of the oil tank. Happens under throttle like going up hills or passing.

Using HD 20-50 oil.

Any connection between the oil delivery system and the new rings?
I installed new rings, crosshatched honing, went together fairly well I thought.

I'm thinking oil pump rebuild time but how would a marginal oil pump make excessive oil return?

Any ideas?

 

Check that you aren't using a 10micron oil filter. The Sportster can't function with too much restriction. It will do exactly what you described, or oil will come from other places.

You should be using a 30micron filter. The 10micron from a Dyna fits the sportster but is too restrictive.

If this isn't it, one of your gaskets (base gasket) may not be aligned with the flow port.

 

By overflow do you mean its coming out of the tank? I think the oil tank should be large enough to hold all the oil, especially if like you said, its kept at the low level.

You might check oil line routing for kinks and such. Also that you dont have any swapped.

On oil filters, I use a 5 micron and it works fine. The filter has a higher flow rate than what the pump is capable of. Sportsters use a gearator pump which is positive displacement. Positive displacement means the pump WILL pump X amount of oil. So lets say the pump puts out 2 GPM of oil @2K RPM. 2 GPM of oil WILL come out of that pump whether its an open line or a 5 micron filter.

 

I'm only going by personal experience and information from S&S Cycle.


http://www.sscycle.com/tech-info/tec...on-oil-filter/

 

Thanks to all respondents, I will review what I can. After releasing some oil, checking and tightening all oil lines, riding another 40km the situation has stabilized.
I would want to know what level the oil should be at with the bike standing straight up, not on the jiffy stand (hate that name, puss* name), any ideas?
Why?
Some alterations have been made so the bike leans a bit more than it did stock.

Cheers to all!

.

 

Yeah thats not even how it works.

The oil filter is not in the return (scavenge) system, its the first thing the oil hits on the pressure side. But even if it was it still wouldnt matter because the scavange pump is also positive displacement. A smaller restriction will not reduce flow from a positive displacement pump.

And heres another one.

Perhaps they should inform Harley

http://www.harley-davidson.com/store...ter---5-micron

I dont use a Harley filter, I use a WIX 5 micron. It flows up to 9 GPM. Dont know for sure but Im betting a sportster oil pump cant flow more than 2 GPM at max RPM.
http://www.wixfilters.com/Lookup/Par...x?Part=1721791

 

I keep mine 1/2 way between the ADD and FULL marks with the bike upright in its normal operating position.

 

Just some food for thought for those that use the low micron numbered filters. Keep in mind if you have your Sportster tuned to idle lower than spec for that nice Harley sound, your oil pump is not working as needed during idle. You will already have less oil flow and pressure because of that and adding a low numbered micron filter will only make matters worse for the lubrication while at idle. This of course will eventually ruin your motor in my opinion.

 

Again, its a positive displacement pump. If you set your idle lower than spec and you suffer engine damage because of lack of oil flow it would have nothing to do with the micron rating of the filter.........it happened because you lowered the idle which caused the lack of flow.

Restrictions DO NOT affect the flow of a positive displacement pump.

 

This is an old debate and has been in play since the introduction of the Twin-Cam engine that calls for a 10 micron filter, and then the introduction of the "premium" filter that's supposed to work in both engine types. (originally 10 microns, the "A" version is now 5 microns.)


The technology of glass-bead filter elements Vs. the old-style paper elements is probably the reason the premium filter works. Glass bead elements flow better than paper elements and resist blockage much better.


The premium filter (and the WIX filter you linked to) has a bypass rating of 8 psi, while the standard 30-micron filters have a bypass rating of 12 psi. Unfiltered oil is allowed to pass at a lower pressure in the premium filter, but the glass-bead element doesn't restrict as much flow as debris gets trapped.


My experience with paper-element filters for TC motors is that they cause an EVO motor to build case pressure and leak in various places.