NADA 3500 air filter cannister

Hello Simon / Eggbert68b
I have a NADA air filter housing for the V8 engine, surplus to my requirements. I no longer have the warm air collector that bolts on to the right hand exhaust manifold, nor the flexible warm air hose that rises up to meet the air filter canister. The vacuum unit on the top of the snorkel is functional, I repaired it. So is the AC-Delco bi-metallic thingydingy in the right side filter canister end. I refinished the unit in silver Hammerite. Make me an offer! Feel free to send me a private message via this forum.
 
How did you repair the magic pulling / vacuum device? on the hot / cold air inlet diverter. I have one that is out of commission.
 
Hello Adrian. I opened the vacuum unit up, slowly and painstakingly, so as not to deform the 'lip' that encircles the one half of the unit. Not unlike opening a tin of paint. Gentle levering with a small screwdriver. I replaced the disintegrated rubber diaphragm (actually just a heap of dust!) with a new one cut from an old truck inner tube! I soldered a new 'hook' to replace the broken one. This part attaches to the mixing flap in the snorkel. Reassembly was the reverse of the above procedure! Reforming the lip to encase the lower half of the unit, trying not to leave it looking too deformed. Lashings of silver Hammerite paint, a new dust collector bulb underneath, new rubber bushes for the mounting points on the intake manifold, and a new mesh from a stainless steel kitchen sieve encased in the original rectangular outer lip finished it all off nicely.
 
The vacuum units are available new. They are handed however. they were used on various English cars but also on American cars. the early seventees Pontiac Trans Am with Ram air (scoops at front of Bonnet) used both left and right handed. I forget which one the Rover uses. I bought a set of two from, I think ,Impala Bob then found them on Amazon....
 
Chaps,
This may sound a tad flippant but is there a need to have a fully functional vacuum unit.
I would like to propose using both the exhaust manifold air source and the bonnet scoop supply as dual cold air supplies.
In a similar way that I have modified the SD1dual warm /cold air sources on past applications, could the NADA temp unit be bypassed and supply dual cold air feeds.
I’ll stand corrected based on your experience. Appreciated Simon
 
The vacuum units are available new. They are handed however. they were used on various English cars but also on American cars. the early seventies Pontiac Trans Am with Ram air (scoops at front of Bonnet) used both left and right handed. I forget which one the Rover uses. I bought a set of two from, I think ,Impala Bob then found them on Amazon....

I haven't had a working vacuum unit for the last ten years and have had no problems, but I would like to get it working properly if possible. What specific part is it exactly that I should be searching for? I have looked on the internet but cannot find anything similar. I know from my own experience that Rover did poach parts from American cars for the NADA's so I imagine this came from a particular make, model and year of American car? Also how does it come off of the original airbox? I don't remember looking but I am sure if it looked like it would come of then I would have taken it off!!!!
 
Yup, it is one of those, without that large rectangular bracket it is sitting on in that photo. The folded lip I was trying to describe is nicely visible in that pic too. When I cobbled mine back together it didn't look quite as nicely rounded and tidy anymore, despite my best efforts.
Using an authentic Trans Am part has got to release a few extra horsepowers too! Not as many as a flaming firebird decal on the bonnet, perhaps, but a few.
 
A lot of the UK ones were made/supplied by ACTS in Salisbury which was I believe a management buyout of the AC Delco . (GM) filter plant in Southampton . For instance they made all the bimetallic valves that control the vacuum actuators . I wonder if a lot of the parts would be common with GM.
 
Last edited:
on the Rover the unit is held on by a spot welded steel strap. Similar to the unit pictured above. You need to drill out the spot welds and replace with pop rivets. The cans can be had without the box shown. I think you may have found the site I bought mine off Adrian...Note what I said about them being handed. The vacuum pickup is at a particular angel to the actuating leg and there is a left and right version. You can of course turn it around and use a longer vacuum line.
 
The valve on the NADA P6b is common to both hot and cold feed - open one and you close the other it is effectively one piece of metal. The actual internal airflow in the filter system is pretty average, not sure why they designed it like that....
 
No need to drill out the welds for the retaining 'strap'. It can be gently bent back enough to extricate the vacuum unit and fit a replacement, then gently bent back to the original position and retained by the 'tongue' on the one end.
 
Back
Top