I pulled the primary case to change the clutch cable yesterday, there was more than 2 pints drained out even though I measured 1.5 pints on refill. It has to be engine oil.


The main seal is new and looked to be in good condition. This is a full rebuild with only a few hours break in time.


The engine oil sumps if I let the bike sit long enough to the point where the oil doesn't show on the dipstick.


My question is that there is a round mesh screen between the clutch and primary drive sprocket on the crank shaft. Is it possible that when it sumps that oil flows through the screen in to the gearbox oil?


If not what is the screen for?


Thanks for any advice!
Steve

 

Might help if you can post a pic of the screen?, perhaps including its location?

There is an "oil transfer valve" in the primary, but only in earlier years [pre-77 i think]. I have seen it only one time but i would recognize it if i saw a pic.

It is misnamed by HD as its function is not to transfer oil; rather it is part of the crankcase ventilation system, but it does transfer some oil as a side effect.

I believe it would transfer oil while the engine is running, not part of the sumping thru the oil pump check valve.

This valve is the reason that the older models use the same oil in the primary and the engine whereas 77-on can use the HD Formula+ in the primary.

 

The screen is just forward of the primary chain adjuster webb.

My Clymer manual shows 3 quarts engine oil, HD 75 and 1.5 pints gearbox oil HD POWER BLEND SUPER PREMIUM. The primary and trans oil are common should it be engine oil in both?

 

Yes, that is the oil transfer valve. It is common knowledge to use the same oil in both the primary and the engine. The primary and trans share oil.

The most common choice for engine oil in IronHeads is 50W in normal climates, 60W in very hot climates, 20W50 in winter. Not synthetic.

Valvoline VR1 Racing oil and Kendall are the most common choices as they have additives [ZDDP] that are needed in old cast iron engines.

These are the choices made by most of the most knowledgeable IronHead guys.

 

Thanks Mick


This makes sense.


Steve

 

the numbers were ment to confuse the public and have them buy from the motor company --HD 75 = 50 weight HD 90 = 60 weight and HD 105 is 70 weight engine oil -- do sweat it on a new motor after a few thousand miles then maybe look in to it

 

Mick, as you know I'm new to the Ironhead .. Can you please provide some links on the current oils used in these old motors?


I'm also concerned about the filter. My 1970 is a XLCH being converted to an XLH. There was no stock oil filter for this model, correct? I think the Kidney tank will accept the drop in oil filter? I don't know how efficient the stock drop in filter is compared to an aftermarket in line filter.


I'm also concerned about oil pressure using a drop in filter compared to an in line setup.


OP, sorry if I stepped on your thread.

 

Most of the forum guys that i know from all over the world agree on the oil choices that i mentioned in my post above ...

http://www.phillips66lubricants.com/.../titanium.aspx

http://www.valvoline.com/ -< this site is down as i type this.

Yes, early Sportsters did not have an oil filter. The stories about the kidney tank oil filter are just old stories about an old horse hair filter. The modern in-tank filter available that i have been using for 5 years is quite adequate.

Oil pressure is not a problem. I doubt that there is any measurable difference between the two types.

Hope this helps