APE cam-chain adjuster leaks...

I haven't looked really close at it yet, but a small amount of engine oil seems to be getting past my APE cam-chain adjuster, and ending up on the bottom cooling fin at the front of the cylinder block.

Will a fiber gasket provide a better (more permanent) seal, versus replacing the o-ring used between the adjuster body and cylinder block? Then there is a 3/8" +/- o-ring that gets chewed up by the threads and jam-nut, where oil may be leaking as well.

Pics?
Steve

swest wrote: Pics?
Steve

Sorry, but I already wiped the oil off the front and probably won't be able to get a good pic of the back, with the carbs in the way...but here's a reference shot from mid-March when the new top-end was coming together.
Oil seeps onto the fin below the adjuster, then runs forward due to the angle of the motor when enough has accumulated. It isn't much of a leak, and just shows up at the front occasionally.
I want to have a seal on-hand, before pulling everything to get at it.

Wow. Shiny. You say the front of the motor? How does the oil get from the back to the front? Seems much more likely to me that the cam chain gallery o-ring that always leaks is what's leaking, and not the tensioner. But yeah, sure, spend $1 on some gasket paper or liquid gasket and see what happens.

Tho you might have a small leak in the adjuster, chances are it's the O ring around the cam chain that's the culprit. Having the crank case breather not connected to a vacuum source will allow the pressure to build inside the engine, thus leaks.
Steve

swest wrote: Tho you might have a small leak in the adjuster, chances are it's the O ring around the cam chain that's the culprit. Having the crank case breather not connected to a vacuum source will allow the pressure to build inside the engine, thus leaks.
Steve

I used the K&N breather for a short time, but the wafting engine odor drove me nuts when the bike wasn't moving. So, the rubber tube to the air box was put back on.
Last observation I didn't see oil at the top of the cylinder, but I'll take a closer look...

It will run cooler that way. It will also prevent pressure build up inside the engine. It's before the filter so that's not a problem. Why anyone would remove it is beyond me. :whistle:
Steve

Next time try this.
Steve

swest wrote: It will run cooler that way. It will also prevent pressure build up inside the engine. It's before the filter so that's not a problem. Why anyone would remove it is beyond me. :whistle:
Steve

When running pods, there is not much choice. I had pods for a short stint a couple years ago, but realized the compromise wasn't worth the problems associated with that, so I went back to the air box. Still have the (like new) pods and breather BTW...

Looking at it closer, it appears the problem is isolated to the small o-ring area on the adjustment shaft behind the jam-nut. That is a tough spot to provide a good seal, since the oil gets past the o-ring by riding along the threads which aren't sealed. Besides, after multiple head swaps, that little o-ring has surely seen it's better days. And with the bike parked most often on the side-stand, that would explain why the oil stayed on the left side, and on the second fin up.

Perhaps if I back the nut off and loosen the bolt enough, I could wipe a coat of Threebond 1211 sealant on the threads before tightening it back up...after a good solvent wash to clean the oil off the adjuster parts. That may do the trick, and save having to remove the unit from the engine, with all that involves...

Pics as requested:

My adjuster leeks a tad too. I'd use RTV to seal it up so you can adjust it. I think you're getting some seeping from the O ring too. Clean it off and spray some powder deodorant around the area and check for leaks in a few miles. I HATE THAT O RING.
Steve

swest wrote: My adjuster leeks a tad too. I'd use RTV to seal it up so you can adjust it. I think you're getting some seeping from the O ring too. Clean it off and spray some powder deodorant around the area and check for leaks in a few miles. I HATE THAT O RING.
Steve

At least we know the oil seals are good between the head and cylinder block...whew!
I've had it more than once, where an oil passage o-ring lets go. Been good so-far this time. I think this exceptional low (8000) mile ZN head has a lot to do with it, requiring very-little prep for use.

When using a one-piece (Cometic) head gasket, are the o-rings still placed in the recesses in the cylinder block to head mating surface?

I suspect it could be used and the holes made larger for the O rings. The one thing I can think of is fitment. The locators, 10mm? The spacing of the cylinders? The new head probably isn't as warped as the old one. I'd check with the supplier if he has a one piece to fit a J head. The width of the gasket around where the O rings would help from leaks if the O rings fail. The early gaskets have a copper ring to seal where you have a O ring.
Steve