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Suspected missing vacuum hose

859 Views 9 Replies 4 Participants Last post by  OVD385P
Hi guys. Had the old girl on emissions machine and of is very high at 11% so suspect air leak somewhere. Was checking vacuum pipes and think something is missing. Please see image attached. Believe there should be a hose on this unit? If so where does it go to? Any advice at all would be appreciated.


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That's the filter for the carb weakener device, the hoses run from the carb plenum to the weakening device and from the weakening device to the filter in your photo. There should also be a vacuum hose from the distributor advance to a t-piece on the hose that goes into the weakener device. Another place where vacuum leaks are common is the vacuum hose to the cruise control bellows or at the bellows itself.
Thank you very much, where is the carb weakening device located please.
Directly to the left of the b-bank carb there should be 2 solenoids together, the forward one is the anti-dieseling solenoid and the rearmost one is the weakener solenoid.
Thank you, will look again as soon as I get back from today's wedding. This will most likely explain my poor acceleration and general lack of power.
Chapter U pg 13 That nipple finds it's way to the charcoal canister under the LF fender thru the fenderwall.


Thank you, just been looking at this, in particular fig U10. Most helpful
I have a home grown 1974 / 5 Shadow 1 like yours I do not think the uk cars were fitted with the charcoal filter canister as shown in the attachments above different emissions control?
My car has the same set up under the bonnet as shown in your pictures
There are no obvious signs of it ever been fitted, which makes sense. However the car has been messed with by previous owner. The distributor fitted has no vacuum unit on it but I have found a vacuum pipe going to the distributor with a screw stuffed in the end to blank it off. The more I look into the car the more confused I am getting..
I have had to retard the ignition timing in order to get any acceleration, but this makes it poor to start from cold.
Doing another wedding tomorrow then taking off road until sorted. Even got local garage a little confused.
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