Engine leaking into primary drive : V-Twin Forum: Harley Davidson Forums

econnor · 08-18-2009, 04:20 PM

This is happening on my 96" S&S Evo. I have changed the engine main seal once about a month ago, thought everything was fixed. I just opened the primary and it is obviously not fixed. This engine has always vented from the heads and the case. I checked the line coming from the case breather and it is not blocked, neither is the case fitting. I can change the main seal again but also need to fix the cause. This engine is almost 13 years old and the oil pump was rebuilt five years ago when the top end was redone. The breather gear is an S&S steel piece, could the problem be with the oil pump?

What could cause almost a quart plus of oil to get into the primary case?

frankysfree · 08-18-2009, 04:22 PM

check your runout on the crankshaft. if it isnt within spec thatll cause it to leak everytime.

springer- · 08-18-2009, 05:25 PM

Though I have never seen an S&S engine have this particular problem it is possible, check this link for information about the case bearing race on EVO engines. It might be worth a look next time you are in there.
http://www.v-twinforum.com/forums/ev...what-look.html

Refresh the page if the pictures don't show up the first time.

strokerjlk · 08-18-2009, 05:46 PM

SPRINGER
good stuff most aren't aware of these issues.
I will add one more that goes along with the same issues.
some aftermarket motors have a insert for the crank bearing seal etc..the insert is pressed in and bolted if these bolts loosen up and allow the insert to flex it will allow oil to pass through to the primary also.
Not sure if S&S evo's use it but std cases and rev tech cases use it

econnor · 08-18-2009, 08:19 PM

I am going to have to get in there and do some exploratory work. I have pulled the outer primary and cleaned out the oil, but maybe this weekend I will pull the primary drive, rotor and stator so I can see what is going on in there.

Lets suppose it is the case bearing, is it fixable? Let me rephrase that, is it economically feasible to repair or is the fix a new case?

Smokedyvr · 08-19-2009, 10:51 AM

Springer,

Not my problem but I truly enjoy the pics and tech stuff you post!

nmaineron · 08-19-2009, 12:09 PM

I would give S&S a call and explain the situation to them.You don't say how old your machine is,it shouldn't be happening in any event.

If it is the bearing insert,rework would end up being a pain,I would opt for new cases.

econnor · 08-19-2009, 01:14 PM

I just spoke to someone at the S&S tech support line. As typical, they were not much help. This weekend I plan to pull the primary drive stuff, rotor, stator and wash the inner case real good. After a short ride around the neighborhood there should be enough oil to pinpoint the source of the leak. Not looking forward to another rebuild this year.

springer- · 08-19-2009, 01:16 PM

You can go to an autoparts store and buy oil dye. Then with a black light you will see exactly where it is coming from.

econnor · 08-19-2009, 07:23 PM

Thanks Springer, your posts are always dead on and very informative.

Honestly, I am starting to look forward to rebuilding this engine. I have been crunching numbers in my head all day.

The engine with the oil leaking is a pretty stout 96". But since the time I put that engine together I have accumulated some components that would make for an even better build. For example: this engine currently has S&S heads, they are ok, but I have a set of STD dual plug heads that were done by Dan Baisley, I also have a set of S&S Billet rocker boxes to replace the XL boxes that are on there now, I just picked up a S&S Billet oil pump to replace the non-billet S&S pump, lets not forget my Jims Hydrosolid lifters. The more I think about this, it is about time to rebuild her.

After the issues with the case are sorted out, I can send everything out for fresh powder coat and high lights. The cylinders will get a fresh hone and some Axtell 30* pistons. All of the hardware in this engine is 12pt SS from Diamond so it will get repolished. I will probably replace the steel breather gear with one of those new reed valves.

This engine currently has S&S 4 5/8" wheels with Eagle rods, RedShift 624 cam, S&S roller rocker arms, Smith Bros push rods, Crane Hi-4E, Super G, S&S flanged cam cover and Jims lifter blocks.

Before this crank was trued it was static balanced at 60% and then the left wheel was sent to Balance Masters to have their active balancing system (mercury filled tube) installed. This engine runs as vibration free as a high compression stroker engine can. My guess is the rods and everything associated with the crank will be ok, might need retruing, but I do not see much work needing to be done down low.

So I am thinking with some fresh powder coat, gaskets, honing, new pistons, and the parts I have collected I should have a very strong engine that looks very fresh as well for maybe less than $1,500.00.

I just have to wait a little for things to cool down before I start working on it. No air conditioning in my garage.

Of course the problem could get solved this weekend and these plans will be put on hold. I will keep everyone posted.

Ed

econnor · 08-21-2009, 09:43 PM

Update:

I just pulled everything out of the primary to look at the main seal, the situation is not nearly as bad as I thought.

The main seal looked buggered up. Like the inner lip may have been pinched on the inside. Looks like a simple seal replacement will fix it. If not, I am definitely going to rebuild it.

Ed