Just finished flathead build. Engine runs strong normally aspirated. I have 2 Judson super chargers. Trying to get either of them working. No luck. Anyone have experience w/these Judsons? Could use some guidance… Cheers, L76
I posted this previously, Ardun heads with Judson supercharger. http://deadlycurves.blogspot.com/2014/12/vintage-feature-on-supercharging-with.html https://ofdc.forumactif.org/t86-the-judson-supercharger-history-and-technics https://www.jalopyjournal.com/forum...d-supercharger-chances.1200431/#post-13676894
Thx. MGTSTUMPY. Cool articles. It’d be great to connect with you (that your Ardon/Judson motor?). As best I can tell... I have everything setup right, but just can’t get it running. Ran great with just the carb and intake though. -L76
Be sure it's turning the right direction; vanes pointing towards direction of rotation. Not directly on topic, but Judsons must be continuously lubed or the vanes will wear out in short order. When new they came with a pre-oiler.
Thx TCTND! Got the marvel mystery oiler hooked up. Vanes & rotation appear to be correct. Can't even get it started, so no vaccuum will pull oil yet. What'd you guys use for vanes? Material? -L76
Also - there is a butterfly valve at the base where the blower feeds into the intake. Wondering the positioning of the butterfly WRT carb / linkage? Might act like a choke. Certainly designed to restrict/control air & fuel. My problem must be air/fuel since the same carb and intake run just fine without the blower. -L76
The butterfly at the base is intended to prevent the blower from seeing a lot of vacuum when you lift off or coast down a mountainside. As long as it's mostly (but not entirely) closed at idle it will be fine. It could be fully open the rest of the time without ill effects. I don't think most kits even came with one so I doubt it was a problem, but someone out there surely knows more about them than I do. P
So butterfly position should not inhibit it from starting. Wonder if there is some sort of vaccuum leak in the system... can't figure out why she won't start. -L76
It will if it's closed. I'd disconnect it from the throttle linkage, wire it open, and see what happens.
I don't see how the linkage on the carb will open the throttle from the angle it is at. Not sure how you have that all set up but just doesn't look right from this point ofview.
Judsons are very similar to the Aussie Wray and Norman superchargers. Vanes are typically bakelite, though later units used more modern materials (like Ferroform F76, a thermoset resin used in quite a few milk industry vacuum pumps). Bakelite is a cotton reinforced thermoset. Be wary of using fibreglass... the glass fibres are harder than the blower casing liner, and will "sand" it away. The cotton in Bakelite does not. Unusual to have a butterfly between huffer and cylinder head. The Norman Deluxe Type 45/75/90 superchargers did though. The butterfly was a simple swinging plate. At low revs the supercharger provides very little pressure, and the inlet manifold goes into vacuum (just like a naturally aspirated car). There is very little vacuum at the suck-through carb due to the restriction of passing through the lazily-spinning supercharger. The poor carb has low vacuum signal, and is also trying to fight fuel dropout in the slow spinning huffer. To combat this, the butterfly closes, opening up a passage directly between the carb and cylinder head. The carb then gets great vacuum signal and no fuel dropout. Your starting problem may well be that at low revs you have little carb suck. The supercharger casing and piping is all full of air. Try priming the casing/piping with some aerostart. Cheers, Harv
Damn that's awesome I thought I wanted to find another Judson, Now I know I am looking for a Norman. Years ago we had a Judson on a Commer truck, ( 1952 so yes on topic) and had a can of Start Ya Bastard , permanently mounted in a spring clip inside the truck, with a length of industrial pneumatic signal line going directly to the intake manifold. I don't think our American and European friends would probably believe us Antipodeans , even if we put a picture up...most likely get accused of photo-shopping it. Only trouble was the truck got addicted to the stuff and instead of being used occasionally, on cold days etc, in the end he just wouldn't start without it! Engine was replaced with a 283 and the Judson went missing , I have been looking for another one ever since! The problem was actually that the starter fluid had washed the bore , and run the rings dry , we couldn't find another motor or pistons for that one. https://www.nulon.com.au/products/aerosols/start-ya-bastard-instant-engine-starter
http://www.judsonguru.com/ https://www.thesamba.com/vw/archive...dson Supercharger Rebuild by Dave Cormack.pdf https://www.thesamba.com/vw/archives/lit/judson/installation/Judson Flathead Ford Installation Instructions.pdf https://www.thesamba.com/vw/archives/lit/judson/tech/2000 Torlon Vanes - Compressor Tech.pdf
Yup try starting fluid to prime it . If she fires see if you can get the fuel to keep it running . If it pops or backfires youll be able to see a vacuum leak usually.
Awesome feature number 2: the Deluxe Norman superchargers were clutched. That red round thing at the front of my picture is a clutch set, driven by hydraulic pressure. The black hoses tap into engine oil (off the cam gallery) and use oil pressure to push/pull the clutch (almost zero flow of oil so it does not rob the bearings). The clutch disengages/engages the blower pully. So driving down the road in a sedate vehicle, flip the switch and suddenly the blower turns on. Mad Max would be proud. Wonder why you'd ever turn if off though? Cheers, Harv
Damn I would love to see some pictures of your grey motor with all the goodies! What sort of crossflow head? Years ago I had a wrecking business , I scrapped the grey motors when I coulda/shoulda kept them . I had no idea how iconic those motors were. A mate came by one day asking for parts, he nearly cried when I told him I had scrapped them, he needed one (probably all of them) for a vintage midget he was restoring. Now that I have seen how well Spanners' motor goes in his HA/GR I am really kicking myself.
I have a 671 blown hemi and my car will run with the blower not hooked up...You must have a major manifold leak somewhere....
Plan is for a reproduction Repco crossflow head, McGee injection, Vertex magneto, Norman supercharger, dry sump, Mitsubishi rods, custom forged pistons. The poor 3-speed crashbox and banjo (LSD centre) will be working hard. Aiming to take the factory 75BHP closer to 200. Jam all that into an FB sedan, and road register it. Nothing like an old hoon . The head has been on order (deposit laid down) for 3 years. Teaching me patience. Cheers, Harv
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