One problem down, now maybe another?

[BossMaverick]

So to refresh everyone, I have the bike that loses oil through the breather. My thought was (and sometimes is) that the rings are shot. I had also found that I had a bad ignition coil that I had been running on all last summer.

I finally was able to install a used coil with new wires (I put new wires the other coil too). Despite it being 10 degrees out and having summer weight oil in it (15W40 rotella), it started better then it ever did last summer. Next week I will be triple cleaning the carbs since I have no idea how long it's been since it had a carb cleaning and they need new float needles/seats anyways.

So now I'm wondering how much of my lack of power is due to the bad coil and dirty carbs and not so much bad rings. I would be convinced the coil and carbs were all of my problems except that doesn't explained why so much oil is lost through the crankcase breather. After I fired it up with the new coil yesterday, I let it run for a good hour with an occasional rev thrown in. I had been putting seafoam in through the spark plug holes to see if it would free up any rings. Since the oil had seafoam in it from doing this, the vapor coming out my breather hose was pretty good. Let me backup a little. Due to how much oil comes out the breather, last summer I had rerouted the breather hose so it didn't dump oil in the airbox. I had the hose in a verticle position today since I had to put the battery back in to run it. After about 40 minutes of running, I noticed the breather hose was full of seafoam, a little water(the bike was been sitting a few months), and a little oil vapor. It was like the fluids from the vapors couldn't drain back into the engine and was just very slowly filling up the hose. After the hour or so of running, the vapors coming out was just a mild amount, nothing too strong (not like I'd guess to make it spit out a quart of oil every 600 miles).

So my question is this, whats on the other side of the crankcase breather cover on the top of the engine? Is it something that should be blocking fluids from returning or could something be plugged/broken? I couldn't find anything diagrams or anything my XS repair CD to show whats under the cover.

Thanks again!

[DGXSER]

Not sure about what is under there, only had one off once and do not recall anything to memorable about it.

To check the rings, run a compression check on the engine. IF the compression is low, then put two tablespoons of oil in each cylinder and rerun the compression check on that cylinder (Do the oil one cylinder at a time as you recheck it for compression). If numbers go up with the oil, the rings are the problem.

[BossMaverick]

To check the rings, run a compression check on the engine. IF the compression is low, then put two tablespoons of oil in each cylinder and rerun the compression check on that cylinder (Do the oil one cylinder at a time as you recheck it for compression). If numbers go up with the oil, the rings are the problem.

Dang, I was so excited about how it ran with the replacement coil that I forgot I had done that (only I used seafoam instead of oil, it was the closest liquid to grab). The compression did go up with the seafoam added. I wouldn't mind the few horses lost from the lower compression if I could figure out a way not to have the oil blown out.

[tarzan]

You should be very carefull running an engine with seafoam or gas or water
or anything other than straight oil in the crankcase.You can burn up the bearings quick.
Also, since you put seafoam in the cylinders, and I'm assuming quite a bit of it , I would drain the oil and replace it with the correct viscosity and then ride it a bit.Then see if the blow by through the vent tube reduces.Is the bike blowing smoke out the exhaust?

[CatatonicBug]

Behind the crankcase breather hose is a bit of a baffle-type thingy. Things can't really go straight up the hose without making a series of turns, and it's designed to catch liquid, and drip it back down into the crankcase. Usually, the only thing that would push oil up out of that hole in any significant amount would be if your oil was overfilled. The hole (on the inside) is above and to the rear of the clutch basket, so there is no way you could get plain seafoam out that hole, unless that is all that is in your crankcase. I would suggest an oil change first, and make sure you don't over-fill it. It doesn't take much to do that.

Seafoam can be run in the oil AT IDLE with no problem. Just don't ride it around at all. Don't put it under any load. Always do an oil change before riding it again.

[79XS11F]

Oil blowing by the rings will be burned and exit by way of the exhaust so that issue if present is not related to oil coming out the breather hose. Is this hose still hooked up to the air box? If so you might be looking at oil off an oiled type air filter that was over oiled or oil being washed off that type of filter by fuel getting into the air box.
Rob

[DGXSER]

Rob,

If the rings are bad enough, the compression can blow the opposite direction pressurizing the crankcase enough to push oil out the tube.

[79XS11F]

The oil level should be well below the crank case tubes outlet from the cases so compression stroke blow by pressure should just get out the vent without forcing oil with it. Otherwise downward movement of the pistons with or without good rings would always be doing the same thing. There's always air moving in and out of that tube. that's the other reason it goes to the air box and has its air filtered. That's what I would expect unless the oil is very over full which has been pointed out as a potential problem.
Rob

[TopCatGr58]

Hey Boss,

Can't recall all details, but if the bike had been sitting for many years, sounds like it might have since you were worried about stuck rings. Sea foam quickly flows past the rings down into the crankcase and oil, and as mentioned can cause bearing damage if run for too long under any kind of load.

But if it's not been run for many years, aside from the rings possibly sticking, compression loss can also be temporary until it gets RE-broken in. Aside from Seafoam, Mystery Marvel Oil is also known for getting rings unstuck. You may want to get some more "cheap throwaway oil", drain the oil, put in fresh, with some MMO thru the spark plug holes, let it sit a day or so, then run it again for 5-10 minutes with NO LOAD, then drain it again, put in GOOD OIL, and then hopefully with some warmer weather, run it for several hundred miles and then recheck the compression readings.

Also, you'll want to ensure that you don't have a fuel system leak that could be getting into the crankcase oil thinning it out adding to the ability for the oil to get vaporized or atomized to blow out the breather tube!

T.C.

[DiverRay]

I second the thought of the bad coil causing a LOT of raw fuel to get past the rings, and cause the problem. I would say change the oil, add a little seafoam to the fuel, and see how it runs. My guess is you will NOT see as much oil smoke, or loss.

[BossMaverick]

I should clarify a little. It was like something behind the crankcase breather cover wasn't letting the fluid drain back into the crankcase when I had the breather hose in a verticle position. As far as the seafoam, the amount I added to the cylinders is at or below when the can says that can be added to the oil. I'm sure the seafoam went straight through the rings and into the oil, then as the oil heated up as I ran it, the seafoam evaporated off which caused more vapor/mist to leave the engine via breather hose (my theory at least). I also know that I have an occasional leaky float seat or two with a combination of leaky petcocks but last year I put valves on the fuel lines so I can completely turn off the gas (I was too afraid to dig into the carbs last year to fix them but now I'm ready), so there shouldn't be any gas in the oil unless one of my valves are defective. My oil level is at the upper level of the sight glass (with the bike level, not on the kick stand).

As far as my history with the bike, I got it about a year and a half to two years ago and have been riding it for a riding season and a half (about 7,000 to 8,000 miles total). I thought any stuck rings would've freed itself by now but some on here convinced my otherwise so that's when I put seafoam in the cylinders. I would love to be able to ride it right now to see if it's help but there is ice on the roads so I can't. I'm just trying to get it running right for this year's riding season.

I guess my main question/concern is how the fluid in the breather hose (in a verticle position) could not drain back into the engine. Could something behind the breather outlet cover be plugged up like a clogged artery?

When the weather does finally warm up so I can ride it, could heavier oil help my problem? I've been using Rotella 15w40 but I'm game to try a bike oil in 20W50 if it might help. Any thoughts?

[DiverRay]

You could pull the vent cover and pour some seafoam down into the area. I would try this just before an oil change! It will "clean the plugged artery" if that is the problem. I DO know the return hole for the oil is fairly small, and if something climbed in and died, it could block it.

[79XS11F]

Hmmm ... if the breather tube or passage way is blocked the crankcase will not breather properly, you would not have oil coming out of the tube and you could run the risk of blowing other engine gaskets / seals. The crank case must breath. Take a funnel and pore some oil into the top of the breather tube and see that this oil flows away at a reasonable rate.
Rob