Crankcase Breather Question
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Glenn
Bonneville T100
Seeker, I am sending a picture of the bike when I first got it that shows how the tubing was hooked up. As I said before there was zero in the way of information as far as how the tubing should have been hooked up. As you can see in the left photo, the tube looks like it came down from the frame tube and connected to the rocker boxes and then connected via a T connector to the elbow and the tubing to the rear fender. The second photo shows that there was nothing connected to the Tower. Since this was the first Triumph I had ever owned and the manuals were so lacking I had no way of knowing whether or not this was the way these tubings should have been connected. What I am now gathering is that the tubing from the frame tube should have connected to the rocker boxes and stopped. the tubing from the elbow should have gone straight out to the rear via the fender. Am I correct so far? Should there have been a tube from the Tower that connected via a T connector that joined the tubing that ran from the elbow tube to the rear fender tube in the original stup? Now hopefully you will be able to undestand why a simple diagram would have solved all my issues when I first got the bike. Never having had a Triumph before this one did not afford me prior knowledge of how the Triumph systems work. Sometimes those of us who have a thorough knowledge of how something works cannot understand why another person cannot see something as easily as we do. I had very litttle problems when I was putting her back together, except for this one and that was because there was nothing in the shop manual or parts manual that made anything clear. Actually nothing was offered in the way of a diagram or a detailed explanation. As I said before I see this all the time and it helps me when I write my articles to remember my experiences and I try not to assume anything. The people who wrote the shop manuals for these bikes did not do a thorough enough job in many areas. This area was completely left out.
The way it is connected now is that there is a tube coming down from the top of the frame at the front and it T's off to both rocker boxes and continues on down to the Tower which is mounted in the inner side cover. The location where the elbow was is now behind the starter and cannot be seen so I don't know if he closed this hole off or what. The end starter mount is over this area so I will have to ask him if it is sealed up or what. Since it is a dry system all of the weep holes that once fed the primary chain are now plugged since there is no longer a need to lubricate this area. I hate to be so vague but there are a lot of questions that only he can answer and tomorrow when I call him I will try to get an answer. So, try to be patient.
The way it is connected now is that there is a tube coming down from the top of the frame at the front and it T's off to both rocker boxes and continues on down to the Tower which is mounted in the inner side cover. The location where the elbow was is now behind the starter and cannot be seen so I don't know if he closed this hole off or what. The end starter mount is over this area so I will have to ask him if it is sealed up or what. Since it is a dry system all of the weep holes that once fed the primary chain are now plugged since there is no longer a need to lubricate this area. I hate to be so vague but there are a lot of questions that only he can answer and tomorrow when I call him I will try to get an answer. So, try to be patient.
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Take another look at the diagram I posted. The dark black hoses are carrying the oil and should not be connected to any of the breather hoses at all.
The lighter outlined hoses are the breather hoses.
I have no idea what those hoses on top of your cylinders are doing in your first picture. If you look closely though, I think there is another hose behind them that is the one feeding the rocker boxes.
The lighter outlined hoses are the breather hoses.
I have no idea what those hoses on top of your cylinders are doing in your first picture. If you look closely though, I think there is another hose behind them that is the one feeding the rocker boxes.
Glenn
Bonneville T100
I do understand from the diagram that the oil system and breather system are seperate. The tubing system you are referring to is a part of the breather system and connects to the Connector Rocker Box Breather (Part No. 71-3313). There is one for each rocker box. The tubing system in front is the oil feed that connects to the Rocker Oil Pipe (Part No. 71-3350) that feeds both rocker boxes with oil. I still have a few questions about some things (such as Grandpauls question about the crankcase breathing since the elbow was removed). I can assume that he covered it over since the starter is located in this area but I don't exactly what he did since I can no longer get a visual of this area since the starter makes it impossible to see in that location. But, I really have no idea. He may have covered it over with the starter end bracket and it still has the ability to blow out the gases, but until I ask him I would only be speculating at best and my assumption may be totally wrong. A question I have (since the diagram you sent which is also in my book) does a good job showing oil circulation but does a terrible job showing the air breather system) is where does the breather tube go on its path up toward the frame. I can follow it up to a certain point but cannot see where it ends in the area where the frame comes together because once again there is no clear visual of this area. I could take the fuel tank off but will wait until we remove the engine to rebuild it to get my answer unless someone else gives me this information after reading this post. I will reply as soon as I can get in touch with Ozzie. Again thanks for all of your (as well as everyone else) in trying to educate me on the T140 breather system. All information is greatly appreciated.
Glenn
Bonneville T100
I forgot to add a couple of pictures to clarrify what I was referring to in my last (above) post. The first picture shows the breather tube connection (Connector Rocker Box Breather) which attaches at the top and the second picture shows the oil supply system (Rocker Oil Pipe) which attaches from the side.
What year is your T140V ??
Mine is a '78 and I do not have those connections at the top-middle of the rocker boxes as you do.
They seem to be not another oil supply to the rocker boxes, but actually another set of breather outlets which connect to the very top of the oil in frame tube under the tank and just behind the steering head.
Oil doesn't reach that high in the frame (it would be above the oil filler plug) so being that far up and way towards the front, it would ensure that oil wouldn't get that far even under heavy braking.
Therefore, I am assuming that those two hoses connect to the other hose coming from the front of the frame and then into the breather system and "probably" to your air box as well. Kind of like a positive crankcase ventilation system where the engine will "re-breath" (via the airbox connection) the fumes that come from the crankcase and rocker boxes.
I also agree that when Ozzie put on the electric starter, it's probably not a closed-off area so allowing pressure to escape there isn't needed by way of the breather hose. But if he blocked off all the places where there's communication to the primary case, then he also blocked off where the gasses would escape.
Maybe GP can assist here as I'm getting a bit confused AND the real authority here is Ozzie since he did all the work and should know.
Mine is a '78 and I do not have those connections at the top-middle of the rocker boxes as you do.
They seem to be not another oil supply to the rocker boxes, but actually another set of breather outlets which connect to the very top of the oil in frame tube under the tank and just behind the steering head.
Oil doesn't reach that high in the frame (it would be above the oil filler plug) so being that far up and way towards the front, it would ensure that oil wouldn't get that far even under heavy braking.
Therefore, I am assuming that those two hoses connect to the other hose coming from the front of the frame and then into the breather system and "probably" to your air box as well. Kind of like a positive crankcase ventilation system where the engine will "re-breath" (via the airbox connection) the fumes that come from the crankcase and rocker boxes.
I also agree that when Ozzie put on the electric starter, it's probably not a closed-off area so allowing pressure to escape there isn't needed by way of the breather hose. But if he blocked off all the places where there's communication to the primary case, then he also blocked off where the gasses would escape.
Maybe GP can assist here as I'm getting a bit confused AND the real authority here is Ozzie since he did all the work and should know.
Glenn
Bonneville T100
1979 T140E. They seem to be not another oil supply to the rocker boxes, but actually another set of breather outlets which connect to the very top of the oil in frame tube under the tank and just behind the steering head. You are correct on that assumption. Therefore, I am assuming that those two hoses connect to the other hose coming from the front of the frame and then into the breather system and "probably" to your air box as well. Kind of like a positive crankcase ventilation system where the engine will "re-breath" (via the airbox connection) the fumes that come from the crankcase and rocker boxes. You are correct again. This is a breather tube that once was connected to the tubing that ran the length of the fender. What confused me was why it originally was not connected to the Tower. Somehow it got connected to the tube running from the elbow (as is shown in the first drawings) to the fender tube. The original configuration should have been the tubing from the elbow running to the end of the fender and the tubing from the top of the frame should have Teed off above each rocker box (as it now does) and then to the Tower (as it now does). Ozzie made this correction when he did my bike. I will ask him as soon as I can make contact with him. He may not have any projects going on and chooses not to go to the shop because of the heat. Let's remember that he is in his 80's. I will report back as soon as I talk to him. At least we are getting this issue resolved. I agree with you that the upper end of the tube is probably attached to top of the frame based on the fact that it is so high that I cannot see the end of it. I also agree that when Ozzie put on the electric starter, it's probably not a closed-off area so allowing pressure to escape there isn't needed by way of the breather hose. But if he blocked off all the places where there's communication to the primary case, then he also blocked off where the gasses would escape. Would he not have to do this to enable the area to be completely dry since I now have a belt and a Norton dry clutch. Another question to ask him.The good thing is that I will be able to see everything clearly once the engine is on the bench this winter being rebuilt. I will definately respond after I speak to Ozzie. Thanks AJ. You are a good man. I don't care what anyone else says about you.
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The way I see it (and it seems to make sense) is that ALL that tubing should be connected together (on a stock 1979)........
1) Breather hose from crankcase
2) Breather hoses from each rocker box
3) Breather hose from front of frame
4) Breather hose from side of main frame backbone tube
5) Breather hose into airbox
6) Breather hose along fender
That is, unless Ozzie added those two breather openings on the rocker boxes and they are not stock???
1) Breather hose from crankcase
2) Breather hoses from each rocker box
3) Breather hose from front of frame
4) Breather hose from side of main frame backbone tube
5) Breather hose into airbox
6) Breather hose along fender
That is, unless Ozzie added those two breather openings on the rocker boxes and they are not stock???
Glenn
Bonneville T100
Makes sense to me. The elbow that connects to the tubing that runs alongside the fender is no longer an option because there is not enough room for the elbow since the starter covered it up and there is very litle area and definately not enough for the elbow. I did find out that Ozzie had a daughter-in-law to die and he is pretty distraught over this as we all would be. She was like a daughter to him. That is why he had not been answering his phone. I will give him some time before I mention anything motorcycle to him. He did not add any openings on the rocker box. What he did about the crankcase opening will remain a mystery until I can talk to him about it.
I know exactly how to solve this problem.
Buy her a BIG box of chocolates, keep stuffing the choccies in the mouth one after the other with gaps just long enough to let her take breather. See? Crankycase sorted!
Buy her a BIG box of chocolates, keep stuffing the choccies in the mouth one after the other with gaps just long enough to let her take breather. See? Crankycase sorted!
I am sorry to hear about the loss of Ozzie's daughter-in-law.
Well, they don't exist on a 1978 T140V is all I can say.
Since I don't have a '79, I have no need to buy a Replacement Parts Catalogue for one.
At least now you know they were there from the factory.
At least now you know they were there from the factory.
Changes like that by Triumph were not unusual at all . There were often changes even duing a model year.
I understand why they'd make the change.....EPA standards.
Its like a positive crankcase ventilation system on a car.
The carb intake sucks the fumes from the crankcase and the rocker boxes and re-breathes them.
Its like a positive crankcase ventilation system on a car.
The carb intake sucks the fumes from the crankcase and the rocker boxes and re-breathes them.
I know the first "E" model (T140E) was introduced in '78, it included all the epa junk.
Much the same as yours without the two small hoses that go to the rocker boxes.
I have the one exiting the rear of the primary cover, the one exiting the top-front of the frame behind the steering head, and the one coming from the upper section of the main frame backbone (on the right) near where you check the oil.....all leading to the one that goes over the fender and exits out the back.
I may have had one to the airbox when the bike was new, but my airbox is now gone with the addition of the Mikuni carbs.
