OK -at wits end on the vacuum stuff....


Information and questions on GL1200 Goldwings (1984-1987)
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leakyroof58
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OK -at wits end on the vacuum stuff....

Post by leakyroof58 »



Recently pulled carb rack and did the seals, etc.
Thought I was pretty clear on the vacuum lines
routing and connections, but due to waiting a
couple weeks for parts I had vacuum lines that
I didn't know quite what to do with. I found the
line from the bottom of the "slow-air-cutoff" valve
was missing entirely, and yes it backfired on decell...
I had already ordered and received the rebuild kit
for that valve, so I put it in. Once the carb rack
was back in, I wound up with 1 line still needing
a home.....coming from carb #4, I recall. It's a very
long line, as if it needs to go over to the other side
of the engine. Only problem is I see nor remember
anything over on that side. I have the Clymer manual,
but the line off carb #4 just goes off into the wilderness
on page 158, diagram 54. Have searched for all variations
of things like "gl1200 vacuum diagram", "gl1200 vacuum
schematic", etc., but so far have turned up empty.
Is there any such thing as a complete vacuum diagram
for this beast ??????? If so, where ???



froche
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Motorcycle: 1985 Goldwing Aspencade (GL1200A)
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Former bikes;
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Re: OK -at wits end on the vacuum stuff....

Post by froche »



Hope this helps.

I took off the secondary air supply valve and supporting lines, much easier in and out! I had to have 4 plugs made for my intakes to plug the inputs, but they are simple to make. As a result of doing that, I had a few ports to cover, and a new line to the ignition for vacuum advance. Also took off the purge supply, and connections , connecting the "blow by" to a tube the ended up dumping in the air under the bike.

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ekvh
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Re: OK -at wits end on the vacuum stuff....

Post by ekvh »

Doesn't one long line go up to the ignition module (black box) to help with timing advance?

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julimike54
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Re: OK -at wits end on the vacuum stuff....

Post by julimike54 »

ekvh wrote:Doesn't one long line go up to the ignition module (black box) to help with timing advance?
Yes it does, in diagram that is labeled port vacuum tube
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Riding anything is a good day!
Mike

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leakyroof58
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Re: OK -at wits end on the vacuum stuff....

Post by leakyroof58 »

Thanks to all who replied. That diagram is almost
identical to the one in my Clymer manual. What I
would up trying is connecting ALL vacuum tubes
together. By sheer luck or good Karma, it starts and
runs fine now, in fact it starts better than it has all spring.
Just need to do some road testing and several heat
and cool cycles to insure no leaks. Then I can put all
the plastic back on. I sure don't want to pull this
carb rack again !! Carb sync adapters arrive tomorrow
so hopefully I will be done with it 'till the next problem.

Again, thanks to all.

Shadowjack
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Re: OK -at wits end on the vacuum stuff....

Post by Shadowjack »

If you don't connect that long line to the ignition module, you won't get any vacuum advance when it's in high gear. If you just connect it to the other vacuum lines, it does nothing, and your mileage will suffer.

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leakyroof58
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Re: OK -at wits end on the vacuum stuff....

Post by leakyroof58 »

Shadowjack - you saved my butt !!!!

After thinking about your comment, I thought back
and even though it was 2 weeks ago I didn't remember
disconnecting anything from the ignition module. I started
checking my hoses, and found that the one from the
'anti-afterburn valve' had come off when putting the
carbs back in! Argh! I invented some brand new cuss
words never heard on earth before, knowing I would
have to pull that mess out again. Re-worked all the
hoses per diagram. Found that the Clymer manual
DOES point out this line - IF you are removing the
ignition control box ! There, on page 197, sure 'nuff
shows the hose coming off the ICU !!! (Hey Clymer -
how 'bout a small note on the vacuum diagram like
"to ignition module" ????) Oh, I guess THAT line isn't
important on that diagram ??

Anyway, I checked the Ignition module - yup, hose
coming off of it, but it's only 3" long and the end was
tucked out of sight. So this time I made sure it went
to the port on carb#4. All back in, and 20 mile test
drive went well. Ah, the joys of buying used stuff !!

Once again, you saved my butt big-time!!! Thank you !

Shadowjack
Posts: 64
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Re: OK -at wits end on the vacuum stuff....

Post by Shadowjack »

Glad I can help once in a while. I've been into that stuff several times over the last five years, so I remember it pretty well.

wiretician
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Re: OK -at wits end on the vacuum stuff....

Post by wiretician »

Just a thought for future repairs. I do a side business of weld machine repairs for a local weld supply since 2002. So, I see lots of different types of machines. Sometimes needing parts, and will sit for a week or more. I Have a simple digital camera I keep in my tool box, that I take pictures before and during disassembly. When the new parts arrive, the sometimers takes over and it is hard to remember what I did or where that wire connector went a couple of weeks later. But, I can access the pics on the computer on my bench and voila there it is. I've done the same in my garage, the older family computer and digital camera went to the bench and is aiding in the (overly extensive) servicing of my 1200. After all I have a few hundred thousand thoughts a day at work trying to keep the electrical at a steel mill going. Just a suggestion, sometimes technology can be helpful.
Experience in the Maintenance Field: Nothing is "Foolproof" to the Talented Fool. There are some that would break an anvil with a rubber mallet.

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leakyroof58
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Re: OK -at wits end on the vacuum stuff....

Post by leakyroof58 »

Thanks wiretician, but in my case a camera would
have done no good, since the line to the ICU was
never hooked up, at least since I've owned the
bike. There was no evidence I ever touched it -
still had years-old dust on it, etc. I had to buy a
splice to connect the line. Had I disconnected it,
a splice would have still been in one end or the
other.

And again, if Clymer had only spent another $.000002
on additional ink with a note on the vacuum diagram
saying "to ICU", I would have checked on it.

Like I said - the joys of buying used stuff !



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