whats this hose for?

[friesman]

My bike has been running like crap for a while now and i finally had time yesterday to have a look at things and clean it up a bit.

I found a hose connector broken and both ends of the hose open and one end has a good vacuum on it, when its plugged the bike runs way better, so for now until I can get the connector replaced is it ok to just plug the hose ends?

Just what is that hose for? Any ideas?

 

Thanks for your help,

 

Brian

Edited June 17, 2012 by friesman

[bkuhr]

hard to tell for sure, but the brass insert looks like you may have broke the nipple off the MAP sensor used for adjusting ignition advance. MAP sensor mounted upside down on same plate TCI and coils on near left side corner. Is this hose comming from the #2(left front) carb boot nipple fitting?

[friesman]

Its not a brass fitting its a piece of plastic that joins the hose together, the other half of the hose is down to the left a bit in the pic, with the end of the hose with the plastic inside facing end on to the camera

[dingy]

Agree with Brian.

 

This is half of the restrictor coupling in the TCI vacuum line.

 

The end that has vacuum will connect to the #2 carb. The other end will go to the boost sensor.

 

Pic attached.

 

Gary

[friesman]

thanks GUys, now i just gotta find one,

is that a special connector or will any connector that fits work?

 

brian

[bkuhr]

Agree with Brian.

 

This is half of the restrictor coupling in the TCI vacuum line.

 

The end that has vacuum will connect to the #2 carb. The other end will go to the boost sensor.

 

Pic attached.

 

Gary

 

Was right about MAP sensor line but did not realize had restrictor in line, thought restrictors was just for sync sticks/gages.

 

To answer friesman question, restrictor used to dampen vacum pulses seen buy the ignition advance sensor. As my stock 83 did not have a restrictor, I think you could get by with just a plastic union to join the 2 tubes back together, or a 1 piece new tube from end to end. MAP sensor to #2 carb boot.

 

You could, and at a minimum need to, just plug the end of tube with vacum with a screw to prevent vacum leak,

but,

your TCI will not provide ignition advance based on engine load until the MAP sensor is hooked back to the tube.

 

With the MAP hooked back into the line, with either new union, or 1 piece new tube, should be nearly satisfactory, but you may find you will need to add a restrictor back in the line.

[dingy]

Any connector will work.

 

This one also served to be an adapter for the 2 different size vacuum lines. Larger hose on the intake manifold, smaller one on the boost sensor.

 

PM me if you want me to send you one I have. I just got to find it, I know I have one.

 

Picture attached of a Doorman replacement that Auto Zone or similar parts stores have. #47311

 

Gary

[friesman]

Thanks Brian and Gary

I am sure I can find that restrictor around here, .....it will be nice to get her running right again.

 

Brian

[KIC]

Thanks Brian and Gary

I am sure I can find that restrictor around here, .....it will be nice to get her running right again.

 

Brian

 

Brian,

 

If you need one I have one that I can mail it ASAP. Did the kickstand arrive yet ?

 

Bill

[friesman]

Brian,

 

If you need one I have one that I can mail asap.

 

Bill

 

Thanks Bill, but I picked up a generic one here, but ive been too busy and/or its been raining so I havnt had an opportunity to see if things will work yet.

 

Brian

[PBJ]

Hey Brian my 86 started doing something similar they other day. The engines started running fast idling around 2800 rpms. I couldn"t get it to slow down and I had to head back home and readjust the idle its okay now and idling about 900rpms. But it reminded me of a problem i had with my car and that was also a vacuum advance issue with a cracked hose.

 

i was about to post a new thread until i read this. is this what your bike was doing? I'd like to know so i know what and where to look first. Phil.

[friesman]

NO mine wasnt idling at all, i was having to keep on the throttle at lights and lots of backfire on decel and shifting. Fast idle speed sounds like maybe an air leak somewhere on a hose though..... sorry, Phil, got nuttin for ya...

 

Brian

[Snaggletooth]

Now ya did it! Ya got mine starting to act up. It is fine on the cooler days but once it hits the 90's and I get some heat built on the motor the idle starts to climb. Only does in on the hot days and on a hot motor. Once the temps drop a bit and the motor runs cooler it's back to fine.

 

Now I got to start chasing vacumn leaks again. Probably a crack in a hose. Geesh.

 

Mike

[PBJ]

Yes thats exactly what happened to me It was a hot night and the engine was getting hot. the idle kept climbing and i could not get it down until i readjusted the idle. I only hope now its not too low. But so far so good.

 

But someone here has had to have had this problem before can anyone give me a direction to go? maybe I need to start w a new thread on this ?