Do I really need to fit a different breather?

Oh god I feel like crap bringing this subject up. Please I hope the Commando gods can forgive me. I have gone through this stuff more times than I should have but for some reason I am up for some punishment. I still have some problems with the 71.... I am definitely doing my due diligence on learning the ways of the experts and trying my best not to fall into the pitfalls and such. I am in a dark hole of crankcase pressure and I am afraid my soul is escaping to the primary.


I can get the rotella 15w-40 freshly placed into the oil tank just above the L mark and get ready for a ride. (No oil in bottom end)

Get the bike around the block or up the street to the coffee shop and things are great.... ATF in the Primary staying red and I am feelin good about things.

I had an issue with oil flooding into the primary before and for good measures I did Hobot's recommended fix with the three studs, red locktite, and I fitted the rubber crankcase seal as well.

Now I get to the second phase of my test, giving it a healthy run over 20mi. I ran it up to get some miles on it and after 50 miles it started pushing oil out of the primary. I can stick my fat head under there to look and see it coming out of the felt seal so I know its overflowin and the chains doing a blender effect.

This is the original problem I had with the primary a while ago. I cannot seem to get it to stop. I have a 71' motor so it has the timed breather. I read stuff back and forth about breathers all over the place but from what I read the timed breather is doing just what I need.

Does anyone have a 71' with the same issue? If so please let me know the secret! I want to get out there and join my fellow Nortoneers (that means you backslider) for a first time vintage meetup but I just dont have the confidence and don't want to lose a quart during the last 50mi....(that was the rate actually)

Cheers,


Ben

Ben, unless your breather is plugged or something like that, where it pressurizes your crankcases to the point of forcing oil past the seal and into your primary, this seems unlikely.

But, why not check it out by following your breather hose up to where it hook to the oil tank and pull it off there and start the motor and feel the air poofing out as the motor breathes. Feel it ok?

Then maybe maybe there is a blockage in the hose that comes out of the oil tank and goes somewhere, usually down into your air cleaner? Pull that hose off and make sure it is clean inside.

Assuming all this breathing stuff is free and working, then it really only leaves the main seal behind your alternator as the place engine oil could be pouring into your primary.

You say you did replace that seal recently? Were properly careful and could not cut it or not seated it correctly?

I doubt very much you may have way overfilled your gearbox recently and it is dumping along the clutch rod and into your clutch and primary, but why not pull the gearbox inspection cover off and verify your level.

I'm just guessing here. But have you checked what is coming out of your timed breather? Take it off the oil tank and put it into a pill bottle or something and start the bike after a few days so there is some oil in the crank case. You should get maybe a few ounces of oil out of the breather and then it should pretty much stop. Make sure your oil tank has a breather. I'm not clear on how the 71 oil tank breathes to the air but undoubtedly it goes into the air filter somehow. Make sure that's clean and not blocked. If your oil tank gets pressurized somehow, that's not good. You could even take it out the back to the air, but I don't recommend that. I have mine going into a catch bottle so I don't get oil dripping around in strange places. My timed breather seems to work as designed, not great but to some effect. But I too did the studs/nuts from crank to primary, and I don't get extra oil in the primary, not that I ever did. It's got to be coming from somewhere and if the studs/nuts are good, the crank seal is about the only place unless it's the GB or you have some extra holes somewhere. It's been known to happen. Someone had some extra holes in the crank that was dumping oil into the primary as I remember.

Dave
69S

The timed breather will work well on a fresh engine. Once it gets up in the miles and the piston rings no longer seal as well as they did when new the timed breather does not have the volume to keep up. It was designed for a docile 500 cc motor not a rippin 750. Jim

1up3down said:

Ben, unless your breather is plugged or something like that, where it pressurizes your crankcases to the point of forcing oil past the seal and into your primary, this seems unlikely.

But, why not check it out by following your breather hose up to where it hook to the oil tank and pull it off there and start the motor and feel the air poofing out as the motor breathes. Feel it ok?

Then maybe maybe there is a blockage in the hose that comes out of the oil tank and goes somewhere, usually down into your air cleaner? Pull that hose off and make sure it is clean inside.

Assuming all this breathing stuff is free and working, then it really only leaves the main seal behind your alternator as the place engine oil could be pouring into your primary.

You say you did replace that seal recently? Were properly careful and could not cut it or not seated it correctly?

I doubt very much you may have way overfilled your gearbox recently and it is dumping along the clutch rod and into your clutch and primary, but why not pull the gearbox inspection cover off and verify your level.

Click to expand...

I have to keep in mind the bike runs without issue for the first 50 miles. I may be going crazy here but mazybe there is a slow flow to the primary and I just notice it after 50 miles in actuality. I have to look closer at it I guess and figure that part out.

I do know though that I replaced the Crankshaft oil seal and when I did so I made sure to get the new one in and seat it well. I talked to the guy at Centuryt Cycles in San Pedro (cool shop) and they said sometimes old cases get hairline cracks at that place. I inspected this closely as I was concerned about that possibility. No cracks found and the seal installed nicely.

Now the rings could be wearing I suppose. I dont know the mileage on the motor but it doesnt smoke and seems to get up and go pretty good. Thats no real indicator though...

I think I am going to pull the tube again and watch the airflow. Last time I did this it was flowing nicely but it was shooting and spittin oil as well.

Also this 50mi marker is happening even though I drain the sump which doesnt get wet sumped either over night. The oil tank seems not to fill the crank too badly.

I will make you a deal. I will send you one of my sump plug reed breathers. Install it and connect the hose that went to your old cam fitting to my breather. Cap the old fitting. Don't bother messing with the crank seal. If it fixes your problem you owe me 175.00 plus shipping. If it doesn't fix your problem I will send you a call tag to return it. Jim

Note; If your bike has a frame crosstube below the sump plug my breather will not fit.

comnoz said:

I will make you a deal. I will send you one of my sump plug reed breathers. Install it and connect the hose that went to your old cam fitting to my breather. Cap the old fitting. Don't bother messing with the crank seal. If it fixes your problem you owe me 175.00 plus shipping. If it doesn't fix your problem I will send you a call tag to return it. Jim

Note; If your bike has a frame crosstube below the sump plug my breather will not fit.

Click to expand...

Now that's a GREAT deal from comnoz !!! (and you should JUMP on that) just my 2 cents, :mrgreen: cheers.

comnoz said:

I will make you a deal. I will send you one of my sump plug reed breathers. Install it and connect the hose that went to your old cam fitting to my breather. Cap the old fitting. Don't bother messing with the crank seal. If it fixes your problem you owe me 175.00 plus shipping. If it doesn't fix your problem I will send you a call tag to return it. Jim

Note; If your bike has a frame crosstube below the sump plug my breather will not fit.

Click to expand...

Breather on the sump plug? Lemme look at that installed! I havent seen that on here. Maybe I havent been looking hard enough? I may definitely be interested!

edit** think I found it... will be reading...new-product-t10721-60.html

As the owner of one of Jim's sump breathers, I would take that deal in a heartbeat. If I weren't already very glad to have one.
Mark

ok one look At that thing and PM sent.

no crosstube under the plug, just a bunch of trader joe bags and oil stains.

I swear I have chased all the other leaks down and the bike is tight as can be. No valve cover leaks, no timing case leaks, no head leaks, no oil tank leaks...

Well at least its not coming out the 3 front primary 'studs'. If it was mine and Wes was hovering about with his timed breather '71, he'd drily tell me its ring blow by and nothing will keep ahead of that on the boil. Interesting experiment to give idea on the pressure contest dominator. Still can't completely put a crank seal out of mind.

You need to take a messy hotted up ride for us then crack the primary and collect the volume, or at least open the chain check plug and eyeball before and after level in relation to the chain. if you filled gear box over the lowest gears that can been seen through the cap then may have to ride all messy a while longer til seeks its natural level. Could put AFT in gearbox so if the drips or primary fill ain't very dark then guess what that implies.

Wes's '71 has a weep from head but nothing else blowing out up to 80 he takes it.

I lost 1.5 or so quart to the primary in 100 miles. I can almost envision a slight seep coming from the crank seal after complete warmup 15 miles or so....

I had the recommended level of ATF in the primary to start with. I have been pretty meticulous about it since I've been monitoring this issue and have had the primary off a few times already.

The crank seals new too. I guess I could replace it again but if I do so I may go with the metal rimmed one and some permatex just to change it up a little.

I wish I had some way to understand the sump because the bike doesn't wetsump bad at all.

I habemt touched it since I parked it so I can check the primary level and report this here too but keep in mind the primary level is what's in there + what's flown out and all over my tire garae floor and highway!!!

I monitored the loss my way of dipstick originally since I don't want to lose the motor on the way home.

Triplex chain only needs oil to cool and flush for the long run, so might be worthwhile to video for us with the cover off to see what's showing up, hehe, before and after getting underneath to plumb the flapper valve. You already know what to do before the mess test. Rest well while wondering why all '71's don't over fill the primary and on items that are supposed to keep the pressure out of the crank case. If rings, so barrel off guess what next step leads to..., next time I'm putting non-melting thread in seam as on Peel and as Schimdt does with floss. Crazy making when only some many weekends left to ride cleanly.