Starting carb

[Dizerens5]

A couple of years ago I read a post about how the starting carb (enrichener) can be assembled the wrong way round somehow. Can anyone direct me to that post, if it's still there? I think this may have happened to my flat-tops.
(It's a long story. Investigating fuel consumption which seemed high I found that a PO had raised the float fuel level by bending the float tabs which raise the float needle. I set all that right, no problem, less fuel used --  until the cold weather and now my 79 has become a sod to start. This gets me wondering about the starting carb assembly but I can't find info about this. Thanks.)

[wilcom]

The info you need is here on Snowbum's site. This link will get you to the right section and he has pics of the Correct and Wrong way to install them.

http://bmwmotorcycletech.info/bingcv.htm

It's a tough read, his site is like asking for a tooth pick and then someone hands you a tree(redwood, and old) and a knife.

[Barry]

It's a common question so we also have it in our very own FAQ section. Snowbum is the airhead master no doubt of that but our diagrams might just be clearer. If they are not  let me know and I'll improve them

http://www.bmwr65.org/cgi-bin/yabb2/YaBB.pl?num=1291933920

[Dizerens5]

Thanks guys that is exactly what I was looking for. I must agree the Snowbum stuff is a difficult read!

[Dizerens5]

This is a thank-you post for the info from Wilco and Barry. I've just taken off the left side carb and sure enough, the enrichener has been installed with the right side disc, stamped R. Without your info I probably would not have identified the problem!

[Dizerens5]

Yes, second carb off, and the two enricheners have been interchanged. Now the "penny has dropped", I understand why a PO went to all the trouble of modifying the floats to raise the fuel level. He did not realise the enricheners had been switched and it was the only way he could get cold-weather starting.

[montmil]

Now comes the chore of resetting the float levels to spec. Just go slowly with the little tabs and check your work often. I'm always afraid these fragile bits will work harden and break.

[Dizerens5]

Montmil I have a pair of new floats. I did not like the idea of bending and re-bending that little strip of metal, like you say. Anyway the old floats were pretty discoloured.

[montmil]

Montmil I have a pair of new floats. I did not like the idea of bending and re-bending that little strip of metal, like you say. Anyway the old floats were pretty discoloured.

 
Good call. [smiley=thumbsup.gif]

[Dizerens5]

Btw both float pivot pins were a bit damaged in their centers and one was a little bent, no doubt about what I was seeing, someone had twisted them out using pliers. But why? I'm no mechanic but even I had no trouble tapping the pins out using a small nail with pointy end blunted with a Dremel. Even to me it seems pretty silly to force the pins out using pliers.

[Bob_Roller]

If the previous owner(s), didn't realize that end one of the pin is serrated and needs to be mated up to the serrations in the carb before tapping it in, that would probably require excess force to remove the float hinge pin .

[montmil]

If the previous owner(s), didn't realize that end one of the pin is serrated and needs to be mated up to the serrations in the carb before tapping it in, that would probably require excess force to remove the float hinge pin .

[size=14]+[/size][smiley=thumbup.gif] What Bob says.

The real danger of laying into the hinge pin is breaking off one or both of the support legs. Now that gets expensive in a hurry!

My experience has been that a close examination -Me? I need a magnifying glass- will reveal the serrated end of the pin. You want to remove the pin with the serrated end coming out first rather than have it cut its way through the smooth bore leg.

[georgesgiralt]

Hello !
I had a success adusting the float level by using the bottom of a plastic water bottle. Select the smallest bottle you can in order to have the minimum gas in it.
This way, you see the float being parallel to the body of the carb...
Then once set, you cant put back the bowl and do the other side.
You have to do it as fast as you can. My bottle was partly dissolved by the gasoline so when doing the second carb the bottle began to act funny.

[Barry]

I had a success adusting the float level by using the bottom of a plastic water bottle. Select the smallest bottle you can in order to have the minimum gas in it.
This way, you see the float being parallel to the body of the carb...
Then once set, you cant put back the bowl and do the other side.
You have to do it as fast as you can. My bottle was partly dissolved by the gasoline so when doing the second carb the bottle began to act funny.  

I have thought of doing exactly what you describe but as you say the type of plastic is an issue.  I could even make plastic copies of the float  bowl at work as we have a vacuum forming machine  - but only in polycarbonate and fuel would melt that. HDPE is the usual plastic for fuel resistance but it always has that milky translucence which might not show up the floats well.  

[tvrla]

O took a 40mm bing float bowl and made a gauge out of it.

First off, the 40mm float bowl will fit on a 32, but the bail isn't long enough I believe. No biggie, just hold it up there while doing the test. Or as I recall, the bail won't go all the way, but far enough to retain the bowl. I used a 40mm float bowl because I wanted it for the larger carbs as well.

Second, I removed the block-off plug for the opposite side choke well. Then it will work on both left and right carbs.

Then I forced the overflow tube down out the bottom a little ways and cut off flush what was inside.

Attached some clear plastic tube to the overflow tube and held it up to the side of the carb.

This way I could see the actual fuel level - which I discovered to be right about the back upper edge of the float bowl.