Vacuum Tree

Beluga

Member
In previous posts michael m. Commented on my Travelall having a "busy" tree. I also think it is leaking and affecting everything attached to it.

Beluga is a 66 Travelall 1000a, 304, auto-transmission (3-speed), brake booster, 3.73 axle, Holley 2-barrel carb 2300.
I am at 6800 ft altitude.

I do have a vacuum gauge, but not sure what to unscrew and attach the gauge to. My carb does not have a port like others do.

1. Is the best option to assume the tree is all bad and just replace everything?
2. Not having done this, what's the best and simplest way to accomplish this?
3. What products to use?

Here is a picture of the vacuum tree. Thank you!
 

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Quick test is to grab a can of chemtool or whatever carb cleaner you have laying around, and spray the hose connections and pipe connections going to the t and their terminations - while the engine is running. Idle will change if you hit a leaky spot with the carb cleaner (probably even out/speed up). And wear safety glasses - that crap really burns if it hits you in the eye!
 
You do have a lot going on there, but the hard lines and connectors should be fine. I'd be much more suspicious of any rotten hoses. It looks to me like you have at least one that's past its "pull date".
 
Thanks Scout and hondo!

The rubber hoses shouldn't be hard to replace, but in respect to all the metal fittings...

Do I take those apart, clean, and reassemble?
If so, are you supposed to use "gas line tape" on the threads of the fittings?
Are some of these compression fittings that naturally should be replaced when taken apart?
And finally... Should I add an extra fitting just for the purpose of testing manifold vacuum?

Craig
 
I'd replace the rubber,then start it,spray either on the fitting's,if it revs up then,takem apart an reseal. If not,then leave the sleeping dog lie. Jeff
 
Sprayed everything, no change in rpms. So I haven't changed anything.
Unhooked hose to brake booster and measured 14.5mmhg of vacuum (I think that was the units). The vacuum did fluctuate 0.5 frequently.
I am at 6500ft.
 
Your vacuum reading is pretty good for your elevation, though it should be steady with no fluctuations. When you rap the throttle, does it drop to zero and then recover to around 15 as speed returns to idle?
 
Yes. I got a better hose fitting and the vacuum fluctuates between 15 and 16. Tap the throttle hard and it drops to zero (a little tap drops it as well but not as far). It recovers to 15 at idle. Higher rpms also keep it around 15.
 
Sounds normal other than the minor bouncing at idle. You might be chasing something that isn't there. How's she drive? Charge hard up some hills. Spend some time cruising between 45-55.
 
She drives pretty well. Needs to be manually choked for the first 5 or so minutes and then is good. But she runs with a gallop (for lack of better word to describe it). I have read a lot on engine sounds here, but I think I am going to try and actually record what it sounds like. To me she sounds like she's "missing". The wavering in the vacuum correlates with wavering in rpms. I will probably start a new thread on this.

Thanks for the help with the vacuum. I had never checked mine and always wanted to have that bit of information.
Ipha members are awesome!
 
The need for choking during initial warm up is quite normal. If you suspect a missing cylinder(s), there's a couple easy ways to check. If you have an inductive timing light, you can connect it to one plug wire at a time and squeeze the trigger. The light should strobe at a steady rate. Any erratic flashing indicates an issue with that cylinder. In the absence of a light, you can carefully pull one plug wire at a time. The engine should stumble slightly each time. If you pull one that makes no change, there you go. Then you have to find out why. Failed plug? Bad plug wire? Bent or missing push rod? Etc etc.
 
Okay cool. Well I will get to that soon. Fell off a ladder 2 days ago and broke an arm and cracked my egg. But as you can see, I am alive.
Appreciate the help!
 
Oh crap!!! I feel your pain, kinda. I recently took a spill climbing out of my semi, landed on my right wrist and broke it in two places.:mad2: gravity is such an evil beeyotch! Happy healing.
 
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