Am working on a 1940 dodge pickup. The master cylinder leaks and needs to be re-bored. I am thinking that this would be a good time to upgrade to a dual cylinder mc for safety. I have a couple of questions. First, the old mc has a three hole mounting pattern. I haven't seen any dual mc's with that pattern. Do they exist or would I be better off making an adapter for a similar bore dual one? Second, how involved is the work of adapting the existing brake lines to the new mc? Are the circuits split diagonally or front and back? Thanks! Posted using the Full Custom H.A.M.B. App!
The main problem with upgrading to a dual master cylinder is space. With the original steering gear box it's tight. Over at the p15-d24 forum do a search and you will find they are using a jeep Cherokee master cylinder and making an adapter for the 3 to 2 bolt pattern. Looks pretty slick to me. I might try it on my '46.
Another MOPAR option is the early 70s Demon/Duster/Dart/Twister/Sport/******* 4 wheel drum cylinder which is a dual reservoir cylinder. It is readily available new from your favorite auto parts store or their warehouse in a couple of hours or a day.
View attachment 2185844 Thanks for the Dart tip. I looked into the specs. It should be a fairly simple retrofit. The four mounting holes are easy to access, and I think will mount to the cross member with little fuss. Very reasonably priced, too. I found one that doesn't have the screws sticking out on the face. Hmm. Come to think of it, I didn't see a flange to mount the rubber protective boot. Well, I will cross that river when the part comes. Details of the part that I ordered can be found at http://www.ebay.com/itm/161246815242 Posted using the Full Custom H.A.M.B. App!
Oops, the image didn't load. Am trying again. Image is of the current mc. Plenty of room around the steering box and starter. I won't be putting it in for awhile, though. Electrical upgrades are underway, as is a sound reduction project in the cab and replacement wood for the rotting bed. The old mc works (it was rebuilt a few years ago) but has some pits where the piston is fully extended, so fluid slowly drips out when the pedal is out. Easy solution would be to move the pedal in by 1/8", but I would rather have two circuits for safety. I have intense memories of my mom's car's brake failure on a steep hill
WOW , Super sweet truck . Love the look of the 40 Dodge truck front end . The dual master cylinder is the way to go . Late 60,s / early 70's manual brake type . They work just fine , and plumbed right , they are much safer . They will fit in the stock location , with the use of an adapter plate , for bolt hole alignment . And a little longer pusher rod , to get full pedal . When you run the new brake lines , you will have to come up with adapters , to connect the newer style line to the older style flex hoses . Good Luck . Have fun it . Your truck makes me miss my 40 panel truck . Cant keep them all . Still got my 47 WC Panel .
Not quite the info you're looking for, but I got a brand new early dodge master from my local napa, was even stocked on the shelf. Spent a couple hours installing and bleeding the brakes and was back on the road just like new. I believe it was only in the $60 range to. Posted using the Full Custom H.A.M.B. App!
I didn't see anyone cover you second question. The lines are split front to back. Shouldn't be too hard making most of your current lines work with the new master cylinder. My vote is for the early dart style. Works well. Posted using the Full Custom H.A.M.B. App!
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