Author Topic: Vacuum Leak  (Read 6057 times)

Offline augustdiesel

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Vacuum Leak
« on: August 20, 2018, 10:54:36 AM »
Got the compressor, clutch, and drier replaced on my suburban, now have cold air finally. However, seems I have a vacuum leak somewhere as the unit is stuck in the split level system, dumping all my cold air on the floor and only trickling out the dash vents. Any ideas as to which line I need to be looking at to get it back to max setting?


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Offline fvaldes27

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Re: Vacuum Leak
« Reply #1 on: August 20, 2018, 09:22:25 PM »
Same issue in my truck, what I know is that the issue is related with a faulty vacuum valve that control the internal gates, still in process to take out all the SC system.

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Offline VileZambonie

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Re: Vacuum Leak
« Reply #2 on: August 21, 2018, 04:48:08 PM »
Is the vacuum source connected to the reservoir under the hood?
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Offline augustdiesel

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Re: Vacuum Leak
« Reply #3 on: August 22, 2018, 08:20:59 AM »
Is the vacuum source connected to the reservoir under the hood?

That I am not sure of. At risk of sounding ignorant, where would I be looking? I have a 6.5 NA diesel under the hood. Previously had a 6.2.


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Offline VileZambonie

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Re: Vacuum Leak
« Reply #4 on: August 22, 2018, 10:15:15 AM »
Can you post a few pictures of your engine compartment and we can help you identify where to go?
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Offline augustdiesel

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Re: Vacuum Leak
« Reply #5 on: August 22, 2018, 05:37:03 PM »
Can you post a few pictures of your engine compartment and we can help you identify where to go?


Yeah I’ve got a few of those!





I don’t have a photo of the passenger side of the engine bay right now but will get one when I get home. Thanks!


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Offline bd

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Re: Vacuum Leak
« Reply #6 on: August 22, 2018, 06:19:31 PM »
Any of the back of the engine with the air cleaner removed and the firewall area from the center to the passenger (right) side?
Rich
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Offline augustdiesel

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Re: Vacuum Leak
« Reply #7 on: August 22, 2018, 09:31:27 PM »
Any of the back of the engine with the air cleaner removed and the firewall area from the center to the passenger (right) side?

I will have to get that tomorrow sometime. Looked through everything I have and couldn’t find anything


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Offline augustdiesel

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Re: Vacuum Leak
« Reply #8 on: August 23, 2018, 11:28:18 AM »
Any of the back of the engine with the air cleaner removed and the firewall area from the center to the passenger (right) side?


Here you go. Just took these.









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Offline VileZambonie

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Re: Vacuum Leak
« Reply #9 on: August 23, 2018, 05:24:00 PM »
Fix your broken vacuum hose and make sure the little hose isn't pinched
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Offline JohnnyPopper

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Re: Vacuum Leak
« Reply #10 on: August 23, 2018, 05:52:56 PM »
Way to go Vile one! Good eye!
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Offline augustdiesel

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Re: Vacuum Leak
« Reply #11 on: August 23, 2018, 07:59:47 PM »
Fix your broken vacuum hose and make sure the little hose isn't pinched


Ya know, I had noticed those and figured they needed replacing just wasn’t sure what they went to. Any idea if a special hose is required and what size? Thanks again! Seems like an easy enough fix.


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Offline VileZambonie

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Re: Vacuum Leak
« Reply #12 on: August 23, 2018, 08:19:04 PM »
Just match them up at the auto parts store
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Offline 75gmck25

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Re: Vacuum Leak
« Reply #13 on: August 24, 2018, 08:13:57 AM »
It looks like your vacuum canister might be mounted differently than mine, but this is how mine looks.

Look at the A/C evaporator housing and the silver accumulator, then look right behind the housing next to the blower fan housing, and you should see the top of a a round black canister.  This is the A/C vacuum canister. In your last picture I can only see two wires (no canister), so maybe yours is missing or mounted differently. 

There is a vacuum line from the intake manifold over to a fitting on the canister, and then a 2nd smaller vacuum line from the canister through a rubber plug in the firewall to the A/C controls.  If you remove the glove box cover you can see up under the dash where the vacuum line comes through the firewall and crosses over to the A/C controls.  This is GM vacuum hard line, so sometimes it gets old and brittle, and you may find it is broken.

Bruce

Offline augustdiesel

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Re: Vacuum Leak
« Reply #14 on: August 24, 2018, 09:29:27 AM »
It looks like your vacuum canister might be mounted differently than mine, but this is how mine looks.

Look at the A/C evaporator housing and the silver accumulator, then look right behind the housing next to the blower fan housing, and you should see the top of a a round black canister.  This is the A/C vacuum canister. In your last picture I can only see two wires (no canister), so maybe yours is missing or mounted differently. 

There is a vacuum line from the intake manifold over to a fitting on the canister, and then a 2nd smaller vacuum line from the canister through a rubber plug in the firewall to the A/C controls.  If you remove the glove box cover you can see up under the dash where the vacuum line comes through the firewall and crosses over to the A/C controls.  This is GM vacuum hard line, so sometimes it gets old and brittle, and you may find it is broken.

Bruce

I will check it out as soon as I can. I cannot see your photo btw if there was one. I’ve marked my intake vacuum hose in yellow, and it routes to a device (marked in red) that is just to the driver side rear of the engine bay, close to where the glow plug relay would be (removed). The intake vacuum line is also split, so all of these lines probably need to be replaced.

 



I’ll get out there during my lunch break and get better photos of these vacuum lines and where they all go


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