Dual Carb Installation, Success - She Screams Options

[rpmmaxxed]

Where did you purchase the carbs from? Reading through the posts, one of the guys mentioned that you were having problems with them right out of the box.

If you bought them from webercarbsdirect, or anyone having any affiliation with them, that could be your issue. I bought a set of 44's from them last year, and ended up tossing them in the parts bin after installing them and trying to sinc them.

I was having very similar issues to you, making repair's and modifying things as need be, and it wasnt until I got to your current state, hooked up the linkage bar, and discovered that some of the parts had been so poorly machined (jets), even hardware (stripped nuts/bolts) right out of the box, that I scrapped them for readily available 40's.

Hope this is not the case, but hoping to bring light sooner than later to what can be a very frustrating discovery...

*Unfortunately it was not until after I made my purchase that I came across many people with poor reviews of them.

[Mblizzard]

John that is what I thought on the float setting. Maybe other things were influencing things or there was some grit left in them from the casting. But I know it is running so much better!

[ThePaintedMan]

John that is what I thought on the float setting. Maybe other things were influencing things or there was some grit left in them from the casting. But I know it is running so much better!

I still think it was the floats... so I'm going to just chalk it up as a "win" for me mentally (IMG:style_emoticons/default/smile.gif) It's only been recently that I've felt like I know enough now to help others, so it at least makes me feel all warm and fuzzy inside. (IMG:style_emoticons/default/wub.gif)

[Mblizzard]

I got the carbs from Redline. I would have to say up to this point my troubles have been due mainly to my inexperience. Not saying your troubles were the same. I have been in contact with them and while a little slow they have been responsive.

[Mblizzard]

While I was setting the carbs last night I happen to think about what to do with the crankcase vent that is in the oil fill port? The previous set up vented it back to the breather. I don't think it should be just plugged? So what are my options? I have seen what appears to be a vent/filter used in some application and others seem to have the vent removed. Thoughts?

[rhodyguy]

2 port exit breather box with the exits hooked to to the 2 vent tubes in the heads. you have to mount it high enough so it's all downhill. still a maint hassle as you need to take the top off the box, squeeze the oil out of the foam insert, and mop up any leftovers. using the carbs to draw off the vapors makes for a real mess inside the air filter area. i have a cfr unit that's much less long drain line i intend to use at some point.

[Mblizzard]

CFR unit is what?

['73-914kid]

Tangerine Racing

The CFR breather can is halfway down the page.

[AE354803]

Is there any advantage to returning the crankcase breather to the intake instead of just plopping a small breather filter on the exit from the breather catch can or running a tube to drip it to the ground? It just seems to send oil mist into the carbs.

I would rather dump this than feed it through my carbs.

Assume I don't care about dripping some oil onto the roads...

[Mblizzard]

I was wondering that my self on the breather. While like many others here I have spent more money than I care to admit on my 914. But I would have to be sure there was not a cheaper option than than the CFR unless the advantages were huge.

As an update to the saga. Got the cross bar installed and adjusted pretty closely. Have not gotten the chance to drive it yet but it sounds wicked when you give it the gas. Thanks for all the help. I hope to take it out for a drive this weekend and I will post the results.

[jmill]

Empi and Bugpak have cheaper $30ish options. Not as good but cheaper.

[Mblizzard]

Well now this sucks beyond all imagination. Installed new CB rotary 3.5 psi fuel pump. Got everything balanced and synced. Took top off and was going for a test drive and the same flooding crap starts. Turn key and restart and it sounds great for a minute and then slows down and dies. WTF is going on here? Turn the key off and restart and the carbs will make the engine roar for as long as you keep it revved but let off it for moment then it slows and dies. I don't even know what to do next, (IMG:style_emoticons/default/WTF.gif) (IMG:style_emoticons/default/WTF.gif)

[DBCooper]

Sounds like your idle circuit is dead. If you just installed a fuel pump could you have introduced some contaminants into the system? Pull the idle jets, see if they're still clean. If you do find they're plugged a good trick is to put a line of grease on the tops and bottoms of the air filters to keep any solids from sneaking in that way. Or alternately get some CB Jet Doctors.

[DBCooper]

Just thinking a little more, those are also the symptoms of a vacuum leak. Are all vacuum lines in place and good, including the distributor advance?

[Mblizzard]

This has been a problem with the carbs since the first start. I have taken them down 3 times and never found a clogged anything. Float level was off in one but nothing else ever seemed to be a problem.

No vaccum leaks. Mechanical advance. I have not gotten it to run well or long enough to think that there is not a fault in the carb.

It is possible that these are just a bad set. I am sending them back.

[DBCooper]

This has been a problem with the carbs since the first start. I have taken them down 3 times and never found a clogged anything. Float level was off in one but nothing else ever seemed to be a problem.

No vaccum leaks. Mechanical advance. I have not gotten it to run well or long enough to think that there is not a fault in the carb.

It is possible that these are just a bad set. I am sending them back.

Did you ever get the Tomlinson Weber book? If so it has diagrams of each circuit in the carbs, so you can use compressed air to check each one for flow, and most impolrtantly for leaks in each circuit. If you're sending them back anyway it might be worth your time to go through those, if for no other reason than to get more familiar with the inner functions. Or, who knows, maybe even find the problem if it's internal to the carbs.

[Mblizzard]

Yep got the book. Read it. Can't say that anything in it that I tried made any difference. I plan to look through it one more time but even if there is something I missed it is hard for me to see how brand new carbs would or should behave this way.

[Elliot Cannon]

I've had problems like that and it was idle jets. It doesn't take much to clog them. By the way there is nothing wrong with the cross bar linkage if it's set up correctly.

[Mblizzard]

Elliot - love the Red!

The more I think about this I am coming to believe it is the idle jets and I think I know why. Maybe hard to see but I happened to be checking the float level again and had the floats side by side. Side by side one looks brand new as it should and one looks used.



The first two photos are of the float that looks used.





Look at the brown rings on the float and note that it appears to be quite scuffed up. In fact, I think that small pieces are coming off this float and clogging the idle jets or other parts of the carb. If you zoom in on the photo on top to the lower right hand side on top of the float you can see a small opening in the covering of the float which releases small pieces when touched.



The last picture is of the new appearing float. I think someone owes new a new float, possibly new carbs, and a week of my life back!

[rhodyguy]

call redline. see if they will take them back. you know what i will suggest after that. another pm sent.

k