| Author | Message | ||
     Kybuell |
Why does the oils reservoir have to be under so much pressure? Can it be vented? Just seems like the pressure could force oil through weak seals into the primary. | ||
| Littlebuggles |
You'll need to articulate why , exactly you believe the system is under a lot of pressure. For instance, you should be able to pull the oil cap out and let it run if the oil is at the right level. You can hear it breath, but there shouldn't be any ill effects to running it like that for a minute, just to observe the system operating - as long as the general area under the seat is clean so you don't drop cruddy road grime into the oil res. There should be adequate pressure to push oil through passages throughout the motor and back up into the reservoir. The XB's had some refinements in their oiling to include spraying oil at the bottom of the piston to cool the motor better, so you need pressure for that too, but there shouldn't be so much that it forces past seals. If your primary is gaining oil from the crank case (and blowing oil out the trans breather) it's because your crank seal is bad. Early seals had only a single lip and the new seals have a double lip which will seal better. My 2000 cyclone wasn't showing signs of leaking but the seal was hardened and broke to pieces when I checked it. | ||
| Sparky |
Well, ahem, if there are weak seals, wouldn't those be the obvious ones that should be replaced? Any pressure in the oil bag is a result of the scavenge side of the oil pump sucking oil out of the crankcase faster than the feed line of the oil pump can take it. This shouldn't affect seals in the primary unless they are worn out. | ||
| Littlebuggles |
Good point Sparky. I was just wondering if maybe his oil reservoir cap popped of due to overfilling (there are, mmmm, certain reasons I know this happens...) and maybe he thought the system was higher pressure than it really is because of that. | ||
| Kybuell |
I'm not saying it hasn't been overfilled a little.  I just know when I remove the oil cap while running and shortly after running it pulls out of the reservoir with a small "pop" letting me know its under pressure. Speaking of the double lip seal....does anyone have the part number handy for this updated seal?. I just did a engine rebuild and my gasket kit came with an old style seal. | ||
| Blackm2 |
HD part #: 35151-74A | ||
| Arizona_buell |
I vented mine after rebuilding , I found the same situation with pressure popping off the cap. I put a tee in there and ran the line to my catch can to relieve pressure. I replaced every seal there was so I know the seals are good and I am not getting extra oil in the tank, just too much pressure. | ||
| Kybuell |
I was considering venting it as well. I haven't checked my primary since rebuilding the motor so I don't know if any oil is getting past the crankshaft seal or not. I don't believe there is but since I didn't use the double lip seal, I've been wondering. Where are you putting the "T" at? In the vent line from the motor before it goes into the reservoir? Thanks for everybody's 2¢ | ||
| Kybuell |
Thanks for the part number "blackm2". That's the number I had but my dealer didn't have one in stock to verify the double lip. I'm just gonna go with that number | ||
| Kevmean |
I would be very surprised if the scavenge side of the oil pump could build up any excess pressure in the tank as the scavenge pump is there to scavenge only and nothing else ....if anything the pump would generate less pressure with age ,are you sure that all the engine breathing system is working as it should and that you are not building up pressure internally in the engine? ....... most pumps generate a certain pressure so if the oil it is picking up is already under pressure the pressure at it's outlet will be higher than it should be. | ||
| Arizona_buell |
I put the t fitting right at the tank vent so the pressure will blow out to my catch can that is vented to the atmosphere. I ran the hose up the frame and over the engine then into the can. Trans vent , head vents , and crank case vents all into the same can. Now I don't have to worry about the lid popping off. As a side not the can has a drain on it and it has stayed dry so to date all is well. | ||
| Buellistic |
OIL SYSTEM Class 101, just PM me for a copy ... | ||
| Dannybuell |
Please share your opinions on this. http://xlforum.net/vbportal/forums/showthread.php? t=72099 | ||
| Harleyelf |
He says to use teflon tape but doesn't mention that the white plumbers tape is oil-soluble and you should use yellow oil-resistant tape. Aside from that it looks great and I may do it to my big twin. | ||
| Kc_zombie |
Never experienced the problem myself, and this ain't my first rodeo. Usually issues like this are an indicator of another underlying problem. Seems to me venting, etc.is not really curing the problem but just working around it...  | ||
| Arizona_buell |
KC I agree, However I just completely rebuilt this engine. New pistons bored out new rings bearings and all seals, I have excellent compression and it runs great so I really don't know where to look for problems. My Shovelhead has been vented to the atmosphere for 31 years with no ill issues. I don't know where the pressure is coming from but I can assume seal and gasket failure are not far behind the pressure, So I relieved the pressure. Any insight is appreciated. | ||
| Kevmean |
An engine will generate pressure inside it's cases purely from the pumping motion of the pistons even if there is no ring blowby ..... I still suspect the issue is insufficient venting of the crankcase if the oil tank is genuingly getting too much pressure in it. Try running all the vents to atmosphere just in case the catch can is too retrictive. | ||
| Arizona_buell |
Well the problem with the stock system is the crankcase vent goes into the oil bag but has no where to relieve any pressure , thus pushing the cap off its seal to relieve internal pressure. So I gave the pressure some place to go , out to the atmosphere. I have had no issues since. The one time it popped off and oil came out it was my fault , I put a bit too much oil in it and it expanded out the top. If I had the vent there it would be in the catch can not on my rear tire and rear brake as it was... While this may indeed be a bandaid I think it is a good idea for me. | ||
| Hootowl |
The crank case vent should not go to the oil bag. Yours does? | ||
| Oldog |
perhaps I am wrong here but the rocker boxes are vented, they communicate with the crank case via the push rod tubes (X1-FSM 3-34). The breathers from the head should not be vented to the oil tank, you can in practice tie it together and vent it with a tee, in that condensate is discharged from the heads ( non xb setup ) I would not do that My 0.02$ | ||
| Arizona_buell |
The cam chest vent goes up to the top of the oil bag , is that not correct? The transmission vent is separate from the crank case vent. And the head vents are separate as well. | ||
| Kalali |
Guys - It would be totally nonsensical to think that the engineers designed the engine so that the owners had to rig something to avoid the oil cap to pop off every time they rode the bike. I'm sure they would have figured something during the past 50+ years building this engine using this design. I'm not claiming my X1 is perfect but I've never felt any pressure, negative or positive, when removing the oil cap. And I've done it many many times to check my oil level with or without the engine running and I keep the level such that the oil is just touching the tip of the dip stick, within 30 seconds of turning the engine off, with the bike in the upright position. The main culprit is almost always too much oil. Next could be blocked or pinched head breather vents. |
