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Pulling vacuum hoses - any tips?

Posted: Mon Jan 01, 2007 11:51 am
by Spookymonster
In preparation for my first TB sync, I've made several unsuccessful attempts to remove the vacuum hoses. The hoses don't budge at all, and I'm afraid I might damage them if I pull too hard. I've even tried a 3/8" line disconnect tool, but can't seem to get the leverage to really work it. Any tips on pulling the hose without breaking it? Would a hair dryer help?

Posted: Mon Jan 01, 2007 1:17 pm
by challey
I'd think the hair dryer would make it harder to remove the hoses, since it would make everything to expand. Might be worth a try though.
Have you tried twisting the hose before pulling and maybe trying to work a little silicon spray up under things?

Posted: Mon Jan 01, 2007 3:26 pm
by Boxer
Grab the hose with a pair of pliers and give it a slight twist to break it loose, then you can pull it off with your fingers.

Posted: Mon Jan 01, 2007 7:35 pm
by Ric
Can't you simply cut them off and replace them with new hose ?

Posted: Mon Jan 01, 2007 8:22 pm
by taosports
Spooky,

You are trying to pull the hose circled in blue I hope? The red circled hose stays put.

Image

Posted: Tue Jan 02, 2007 11:43 am
by Spookymonster
Yes, I'm pulling the blue hose.

I'll try and give it a few more twists tonight and see if it helps.

As for replacing the hose, I'd rather not; the fact that I cannot see where the other end terminates makes me think running new line might not be so easy...

Posted: Tue Jan 02, 2007 1:16 pm
by CycleRob
Spookymonster,

Turning the frozen-on portion with a strong finger grip should break it loose.
If not, then just cut off the hose 3/4 inch from the end and carefully carve the remaining stub off with a knife. There's enough hose left in it's loop to reconnect it.

Just be careful that the forces you use do not break off the brass pipe that's cast into the throttlebody.

Posted: Tue Jan 02, 2007 8:39 pm
by Ric
Spookymonster wrote: As for replacing the hose, I'd rather not; the fact that I cannot see where the other end terminates makes me think running new line might not be so easy...
Looks like there's plenty of hose there; if so, just cut them off right at the spigot. Then use a sharp knife point to cut down the middle of whats left on the spigot and peel it off. You're gonna loose what, 3/8" of hose. If the hose is long enough it won't matter.

Hey, and while your at it install some sort of "T" with a screw-off cap in line with the hose so you don't have to fool with the hose next time around. Just a thought.

Posted: Tue Jan 02, 2007 11:56 pm
by CycleRob
Ric,
Adding a T in the line is a clever idea, but it will actually make a good TB synch impossible. Each spigot needs a direct solitary connection to the TB synching device. Putting an access T fitting in there will give you something approximating the average difference between the 2 cylinders. Not good.

Normally, each lower vacuum line goes to the same T fitting that connects them to the charcoal canister's solenoid operated purge valve. That means the 2 lower vacuum lines are connected to each other when the bike runs. They are T'd together so each cylinder receives the same sometimes fuel-rich purge air from the canister and the Motrionic has an easy job leaning out the fuel injection to maintain smooth running. The vacuum hoses also inadvertantly serve as a micro-balance tube that, because of their small ID and therefore low flowrate possible, is only able to erase the small throttle opening differences between the 2 throttle bodies. These small ID balance tubes do the most good at idle, when the flow is low, the running vacuum is medium high and an imbalance would be heard as a loping, uneven idle.

Posted: Wed Jan 03, 2007 9:28 am
by Spookymonster
Speaking of ID, how wide is the vacuum hose's? I bought some 3/8" ID clear hose for my DIY manometer; will that fit?

Didn't have time to work the hoses last night. Will do tonight...

Posted: Wed Jan 03, 2007 5:06 pm
by BchrisL
They make pliers to pull the hoses, but you don't want to pay for them.
Try a pick like one of these
Image
to loosen the hose then it should come off easily. Just put a little silicon greese on the pick and work it under the hose, while gently pulling it near the end.
Chris

Posted: Wed Jan 03, 2007 6:30 pm
by Ric
CycleRob wrote:Ric,
Adding a T in the line is a clever idea, but it will actually make a good TB synch impossible. Each spigot needs a direct solitary connection to the TB synching device. Putting an access T fitting in there will give you something approximating the average difference between the 2 cylinders. Not good.

Normally, each lower vacuum line goes to the same T fitting that connects them to the charcoal canister's solenoid operated purge valve. That means the 2 lower vacuum lines are connected to each other when the bike runs. They are T'd together so each cylinder receives the same sometimes fuel-rich purge air from the canister and the Motrionic has an easy job leaning out the fuel injection to maintain smooth running. The vacuum hoses also inadvertantly serve as a micro-balance tube that, because of their small ID and therefore low flowrate possible, is only able to erase the small throttle opening differences between the 2 throttle bodies. These small ID balance tubes do the most good at idle, when the flow is low, the running vacuum is medium high and an imbalance would be heard as a loping, uneven idle.
You are correct sir....I didn't mean to say just a simple 'T' that would still be open to any other passage, although that is what I implied isn't it. Sorry.

It would have to be a bit more sophisticated than a simple 'T'. It would need to be a 'T' (or something) which would close down all paths from itself except the single path to the TB.

One would need to use their head to devise the correct arrangment. I did something similar on my 79 CBX; giving me easy access to six carbs was a relief indeed !

Image

Posted: Wed Jan 03, 2007 10:33 pm
by Spookymonster
Wound up cutting the hoses off. The left side snapped when I tried to pull it, but it was a nice clean snap, right below the brass nozzle. I then sliced the bit of stuck hose; it was still quite stuck to the nozzle, with bits of dried white (silicon grease?) around the top. Since I'd cut one off already, I figured I'd go easy on myself and cut the right one off as well. The new hose ends posed no problems going on or coming off.

The 3/8" tubing I'm using for my makeshift sync stick went on easily enough. Assuming I have a free hour or so this weekend (HA!), I figure I'll give my first TB sync a go.

Good thinking on those picks. I'll have to check out my local Home Depot for one this weekend. While I'm at it, I'll take a look in the plumbing section for a 3/8" T connecctor w/ caps.

Thanks everyone for your help!

Posted: Wed Jan 03, 2007 10:55 pm
by Sunbeemer
Mine were grown together too, so I just cut them below the brass spigots and reattached the remaining hose after I got done synching with no problems (there's plenty enough hose). I also got the short hose pieces off the spigots intact and used them inside the too-large hoses that came on my Twin-Max Synchronizer so that I could attach them snugly to each throttle body during synching.

Posted: Wed Jan 03, 2007 11:07 pm
by CycleRob
You do NOT need a T connector!!
Use this .PDF download to correctly guide you thru the TB synch process:
http://advwisdom.hogranch.com/Wisdom/TBS4Dv1.0.pdf

It spoon-feeds novice mechanics so they do not make any mistakes. I give it an A.

Posted: Thu Jan 04, 2007 7:31 am
by Ric
CycleRob wrote:You do NOT need a T connector!!
Use this .PDF download to correctly guide you thru the TB synch process:
http://advwisdom.hogranch.com/Wisdom/TBS4Dv1.0.pdf

It spoon-feeds novice mechanics so they do not make any mistakes. I give it an A.
Yeah Spooky...you novice... :wink: :wink: :wink: ....you better forget the 'T' connection idea. A BMW Box doesn't need any such rig anyway.

Posted: Thu Jan 04, 2007 9:42 am
by Spookymonster
After doing a little research, I have to agree that a 3/8" PVC 3-way valve would be both unnecessarily bulky and cost-prohibitive. Oh well.

As a side note, I pulled my CCP this morning before riding in to work. The surging completely disappeared. If the TB sync doesn't make a drastic difference, I can always use this a last resort.