R75 right intake oil drip

[ebeeby]

I have checked the breather hose and it is NOT touching the black plastic air intake tube. The breather itself is the upgraded variety.
I get an occasional oil drip (a drop or two) from the lower joint before it enters the carb. You can see the fitment isn't quite right but it was the best I could get it early this year when I had to pull the jugs for pushrod tube seals.

1) Is there a trick to get the fit better where the black plastic tube enters the rubber boot that couples it to the carb? Maybe I should (carefully) use a heat gun to get things soft?

 

[ecjjce]

Reversed?

Hi there-

I think you may have the intake tube reversed, or upside down. I believe the double clamps are on the case side and not the carburetor side, but am not super familiar with this year (1973?) R75/5, but definitely worth checking.

God luck,

ECJ

 

[stevenrankin]

No help

I am sorry, I can't give you any help or ideas.

I am just chiming in to say "I hate this stupid method some engineer designed for this purpose"!

I may just be stupid but I always have a problem putting the danged things back together. St.

 

[20774]

I think ECJ is on to something. My /7 is exactly reversed from what you have pictured. I also think that Snowbum has mentioned that the screw buckle on the bottom hose clamp should not be at the 6:00 position...rotate it a bit so that the flat band of the hose clamp is making a solid connection.

Also, note that the air intake tubes are different left to right. The right carb is located a bit farther aft because of the offset on the crankshaft for the cylinders. So, be sure that the shorter of the two tubes is on the right side.

 

[jhall]

Close Enough

The OP's pic looks close enough to me, and is about same as mine, which I disassembled yesterday in prep for other work to come. I noticed the right side had more oil in the elbow than the left side. It is just a primitive version of PCV, and an occasional drop of oil is not an issue for me at this point in life. Though I did remove the factory PCV on the R100/7, decades ago. I removed the entire hose, from breather to elbows, and inserted wooden plugs into the housing holes. I then ran an external, 5/8" hose from the breather to behind the air cleaner box, and allowed it to, "draft" as many cars did in the 1960s via a, "road draft tube". It kept the elbows clean, and very little oil came out of the 5/8" hose, since there's less vacuum via road draft. I may also do the same to the current Airhead, just because I can. LOL

 

[m_stock10506]

Hi there-

I think you may have the intake tube reversed, or upside down. I believe the double clamps are on the case side and not the carburetor side, but am not super familiar with this year (1973?) R75/5, but definitely worth checking.

I have a '74 and an '84. The 1974 /6 has the "sleeve" and two metal clamps next to the carbs, just like the photo above. The 1984 R100 has the sleeve and clamps up by the airbox. Never had a problem getting them to fall into place. The "trick" is to have everything a bit loose until you have it all lined up, then start to tighten the clamps.

 

[pauls1150]

It's been a long long time... but I seem to recall that the seam should be facing down, so your tubes may be reversed left to right.

 

[ebeeby]

All good input. In looking at the other tube, yes they are different and the left side seems to have less "90" in it, and yes, the right side carb is further aft, but seems to "need" more "90" in the tube.
Anyone have /5 photos of both sides with good fitment? I replaced these tubes oh, 15 years ago and oriented them the way the old set had been...

 

[20774]

I replaced these tubes oh, 15 years ago and oriented them the way the old set had been...

BTDT! I had been working on my /7 for a few years and happened to stop into the old BMW dealer in St. Louis. Just visiting I think. Anyway, the service manager came over, we were talking, and he said right away that my air tubes were on upside down. Who knew? I had simply replaced them the way I found them...or maybe I had removed them once and didn't pay attention to how they came off and put them back on wrong. It can happen!

I don't have a /5 but likely someone will step up with some pictures. Here's a picture of the right side on my /7. What I notice on mine is that the turn on my tube happens closer to the engine than in your picture. By making the turn sooner like mine, it lines it up to the intake side of the carb better. Your turn happens so late, that it's not finished completely before it reaches the carb. What does the tube on the left carb look like? Is there any chance your right one should be on the left? And I win on the dirty carb contest!

 

[daz]

BTDT! I had been working on my /7 for a few years and happened to stop into the old BMW dealer in St. Louis. Just visiting I think. Anyway, the service manager came over, we were talking, and he said right away that my air tubes were on upside down. Who knew? I had simply replaced them the way I found them...or maybe I had removed them once and didn't pay attention to how they came off and put them back on wrong. It can happen!

I don't have a /5 but likely someone will step up with some pictures. Here's a picture of the right side on my /7. What I notice on mine is that the turn on my tube happens closer to the engine than in your picture. By making the turn sooner like mine, it lines it up to the intake side of the carb better. Your turn happens so late, that it's not finished completely before it reaches the carb. What does the tube on the left carb look like? Is there any chance your right one should be on the left? And I win on the dirty carb contest!

So what's that piece of string for?

 

[20774]

So what's that piece of string for?

Good eyes! It's part of the "belt and suspenders" to hold the right side battery cover on. I loop the nylon string around both plastic hooks on the inside of the covers...in the middle I used one of my Boy Scout knots, a tautline, to draw the string tight. It's amazing that piece of string has survived this long...not been lost or eaten up by battery acid...been doing it's job for over three decades!

 

[daz]

Good eyes! It's part of the "belt and suspenders" to hold the right side battery cover on. I loop the nylon string around both plastic hooks on the inside of the covers...in the middle I used one of my Boy Scout knots, a tautline, to draw the string tight. It's amazing that piece of string has survived this long...not been lost or eaten up by battery acid...been doing it's job for over three decades!

Geeze I have not seen a tautline for years. I have to practice that useful knot. I almost always use a half hitch where that tautline would be more useful. Thank you!

 

[Omega Man]

There is a piece of string like that holding the galaxy together
om

 

[cycleman2]

Pretty normal to get a bit of oil in the right side as the breather hose directs the oil mist from the crankcase to that side. And yes in the original picture the intake hose is upside down, 2 clamps on the breather and one at the carb.

 

[20774]

Geeze I have not seen a tautline for years. I have to practice that useful knot. I almost always use a half hitch where that tautline would be more useful. Thank you!

Half hitches seemed like the thing to use when you were bringing your horse up to a rail...not that I've done that! But easy to twist two circles opposite directions and slip over the end of the rail. I always used the tautline when setting up the side ropes to hold up my tent when on scout camping trips...we needed adjustment to get the proper tension. Then of course, there was the bowline...always was kind of trick to learn how to tie one with a rope around your waist, like they threw a line to you in a swift river...one hand to hold the line while the other ties the knot. Knots were fun!!

 

[ebeeby]

Update: I think I tightened the clamp on the lower end of the black plastic tube too much causing it to "kink" and allow oil to condense there and drip out. I think I did this when a slight drip developed long after initial assembly when I replaced the pushrod tube seals a year ago. Upon disassembly oh, a month ago, I massaged the "kink" out of the lower end, re-assembled, being careful not to torque the clamp down too much though the second clamp to the carburetor can be well tightened. Leak has stopped.....

 

[1074]

Just remove that sleeve and everything should line up. The sleeve was used on later models.

 

[20774]

Something that might help is to rotate the clamp a little away from the turnbuckle being at the bottom. Turning a little bit gets the full band of the clamp to lay along the plastic, not give it "room" to buckle.

 

[crouthier]

Hi, here's photos of the right side of my '72 /5. For reference.

Chuck

 

[ebeeby]

AH-so. I will have to see if the black elbows will work like that...