'66 J3600 Brakes

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Brly
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'66 J3600 Brakes

Post by Brly »

Hi Folks,
I'm new here, guess this is an intro too. Been lurking for a while, but now have a reason to post! Sunday I brought home a 1966 J3600. I recently deleted my photobucket account (for obvious reasons I hope), so I'm trying to figure out tapatalk. I read somewhere you can post photos right from your phone? I'll get pictures up when I figure it out.
Anyway, in my opinion, the truck is in pretty good shape. Per the PO, it just needs a fuel pump to run. Its been sitting for a few years, so I'll go over everything before I try to start it. It appears to have all original equipment (AMC 327).
The other big issue keeping it off the road is brakes. The pedal goes right to the floor with no resistance. The PO said there was a vacuum issue. This truck has the Midland power brake booster. I pulled the front driver side drum off and was pleasantly surprised to find everything in great shape. Someone was in there not long ago. Drums are flat and shiny, shoes have lots of life left and aren't cracked, springs still have paint on them and the wheel cylinder looked perfectly fine. Timken bearings. I need to get the appropriate socket to get the axle nut off the rear before I can see what they look like, but I'm feeling pretty good after seeing the condition of the front.
The master cylinder is dry and I haven't even touched the booster yet. I honestly know nothing about boosters. So, I'm here looking for an idea of where to start troubleshooting the brake system. I'll clean out the MC since it was a little junky, but beyond that, should I just add some brake fluid and try to find leaks? I understand I won't be able to troubleshoot the booster until the truck is running and I have a vacuum source.
The service manual says I should still have manual brakes even if the truck is not running or there is no vacuum.
I'd appreciate any information anyone has. Is the Midland booster any good?
Thanks in advance!
Ben
1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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Brly
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Re: '66 J3600 Brakes

Post by Brly »

Just trying the photos out. I'll add more later!
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1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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Kaiserman
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Re: '66 J3600 Brakes

Post by Kaiserman »

Those boosters can be rebuilt. If the diaphragm isn't bad you might try cleaning it up and running it. There isn't much inside them. Very similar to the boosters Fords used (also Midland products).

That said if you master is dry you need to start there. If it's an old master I'd just replace it. They are available for very little. If the truck has been sitting for a long time, replace the wheel cylinders as well. Again, very cheap. Then bleed it all out and see what you've got for a pedal.

One thing to remember though, is that the slave cylinder on the booster needs to be bleed out as well.
1971 J2500 Gladiator Custom-Cab Platform Stake on 126" wb. B350/T18A/D20 D60/D60-3 w/locker 4.10's Ramsey 8klb PTO winch, Day-brook dump. 225/95R16's
1969 J3800 Gladiator 3407Z Camper Truck. B350/T18A/D20 D44/D60-3 w/4.10's
1968 Wagoneer Custom 327/TH400 Mostly Stock
1987 Cherokee Laredo 2-Door 4.0L/AW4 4" lift OEM swing out tire carrier and brushguard
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Kaiserman
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Re: '66 J3600 Brakes

Post by Kaiserman »

Those boosters can be rebuilt. If the diaphragm isn't bad you might try cleaning it up and running it. There isn't much inside them. Very similar to the boosters Fords used (also Midland products).

That said if you master is dry you need to start there. If it's an old master I'd just replace it. They are available for very little. If the truck has been sitting for a long time, replace the wheel cylinders as well. Again, very cheap. Then bleed it all out and see what you've got for a pedal.

One thing to remember though, is that the slave cylinder on the booster needs to be bleed out as well.
1971 J2500 Gladiator Custom-Cab Platform Stake on 126" wb. B350/T18A/D20 D60/D60-3 w/locker 4.10's Ramsey 8klb PTO winch, Day-brook dump. 225/95R16's
1969 J3800 Gladiator 3407Z Camper Truck. B350/T18A/D20 D44/D60-3 w/4.10's
1968 Wagoneer Custom 327/TH400 Mostly Stock
1987 Cherokee Laredo 2-Door 4.0L/AW4 4" lift OEM swing out tire carrier and brushguard
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44bz
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Re: '66 J3600 Brakes

Post by 44bz »

That’s a great looking truck! I converted mine to power breaks with an aftermarket hot rod style setup. As for the fuel pump, the mechanical ones seem to be getting rare. Searching by 60s amc ambassador with 327 might go better. Or make the switch to electric.


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1968 J2000 - AMC 327/T18/D20 (twin stick), stock D44s, 3" body lift, 35x12.50 Goodyear MTRs w/ Kevlar
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Brly
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Re: '66 J3600 Brakes

Post by Brly »

Thanks guys. I think the master cylinder has been replaced no long ago. Same with the wheel cylinders. I'll post a photo. I've only been into one brake so far. I'll have to see if the rest are equally as good as the first.
I read the service manual regarding the booster and saw it needs to be bled. Bleeder is right on top.
Sent an email to Kanter regarding the fuel pump. I think they have what I need, just wanted to confirm before I buy one.
Thanks,
Ben
1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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Brly
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Re: '66 J3600 Brakes

Post by Brly »

Fuel pump is on the way. I asked if they could rebuild the one I have for a spare and they declined. Haven't looked around for a rebuild kit yet.
Trying to find a hub puller to get the rear hubs/drums off. Hate to pay $150 for a tool I'll barely use. Can't find anything local to rent, so I guess I'll bite the bullet.
Got the rear axle nuts off easily with a 3/4" drive breaker bar and a cheater pipe. I think the rear brakes are in worse shape than the front. Different drums on each side. Looks like the driver's side is fairly new. I'll get them opened up and see what needs replaced. The brake line fitting and bleeder looked pretty rough from the outside. Hopefully the drums are ok.
Ben
1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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tgreese
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Re: '66 J3600 Brakes

Post by tgreese »

Check on earlycj5.com - they can recommend where to get the needed puller for the best price. It is possible to make your own hub puller if you can weld.

J3600 is the 6000 GVWR truck? If so, you should have a Dana 44 rear axle and 11"x2" Bendix brakes. Parts for the Bendix brakes are plentiful and cheap.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
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Topic author
Brly
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Location: North Central PA

Re: '66 J3600 Brakes

Post by Brly »

Thanks for the heads up on the cj5 site. I ended up reserving a puller at Napa.
The J3600 is the 6000 GVWR truck. Confirmed by the serial number tag on this truck. The front axle is a Dana 44, but the rear definitely is not. I assume it's a Dana 60, but I haven't confirmed that yet. I'll see if I can find the tags on it tonight.
Thanks,
Ben
1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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tgreese
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Re: '66 J3600 Brakes

Post by tgreese »

Maybe a Dana 53? It's an oddball axle - nothing wrong with it, just very little support today. Pretty sure the 60 never came with tapered axles. The 60-2 that replaced the 53 had flanges. Both the 53 and 60-2 are 5-lug and were used in the intermediate GVWR trucks. You have a PN from the tag? If a 53, it should have the 12"x2" brakes, which is a problem. There is no source for the 12" drums.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
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Brly
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Re: '66 J3600 Brakes

Post by Brly »

Serial Number starts with 3406X. Looked it up in the service manual and it is a Dana 53 rear axle with 12" drums.
Guess I'll see what the drums look like when I get them apart tomorrow night.
Can 11" drums (or anything else) be swapped on? I understand I would need the backing plate and all of the guts.
Thanks,
Ben
1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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timwiller
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Re: '66 J3600 Brakes

Post by timwiller »

we may have sister trucks, small rear window and all. mine is 3406X100392. some PO nut put in a 304, not recommended. i knew there had to be another one left. i've had mine 15 years and never seen another. will post pics when i figure that out. will try to keep in contact when my crappy rural internet behaves??!! @$#$%%^&!
1966 J-3600 Gladiator. 304, T-18-D20 [twin stick] ,D44-D53, magniflow exhaust
Your 50 year old FSJ IS your hobby!! :lol: :lol:
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timwiller
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Re: '66 J3600 Brakes

Post by timwiller »

http://www.ifsja.org/forums/vb/showthre ... +gladiator go here ...this is easier than screwing with new pics. i did all that brake stuff too. when they are hot or wet you have to watch your separation still.
1966 J-3600 Gladiator. 304, T-18-D20 [twin stick] ,D44-D53, magniflow exhaust
Your 50 year old FSJ IS your hobby!! :lol: :lol:
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Brly
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Re: '66 J3600 Brakes

Post by Brly »

timwiller - nice truck! Mine is 3406X100260. I've got a lot of work ahead...
Rolled under the rear end again tonight and confirmed "53" on the rear axle.
Wasn't successful pulling the driver's side hub so I tried the passenger side and it popped right off. The drums are 11", so someone has changed them out already. Cracked the brake line fitting loose and the line twisted right off. Looks like I'll be running new brake lines.
I put the hub puller back on the driver's side. I'll keep beating on it and tightening it up until it comes off. Tried a plumbers torch but didn't get anywhere with that. I couldn't really beat on it as much as I wanted. I'm working in an attached garage and the kids are sleeping...
I'll post again soon with some questions about the fuel pump I got.
Ben
1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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timwiller
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Re: '66 J3600 Brakes

Post by timwiller »

welcome to the madness!!!
1966 J-3600 Gladiator. 304, T-18-D20 [twin stick] ,D44-D53, magniflow exhaust
Your 50 year old FSJ IS your hobby!! :lol: :lol:
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Topic author
Brly
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Joined: Mon Dec 11, 2017 6:50 pm
Location: North Central PA

Re: '66 J3600 Brakes

Post by Brly »

timwiller wrote:welcome to the madness!!!
Thanks! So here is a photo of the pump I took off (left) and the pump that came in the mail today (right). I'm a little miffed because I sent a photo of my pump to the vendor and asked them to confirm I was getting the right replacement. However, the pump lever that ride on the cam appears to match the old pump. Can anyone tell me if this pump will work on the 327?
Ben
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1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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timwiller
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Re: '66 J3600 Brakes

Post by timwiller »

AMC forums...
1966 J-3600 Gladiator. 304, T-18-D20 [twin stick] ,D44-D53, magniflow exhaust
Your 50 year old FSJ IS your hobby!! :lol: :lol:
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44bz
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'66 J3600 Brakes

Post by 44bz »

The pump on the left is the same that was on mine. The pump on the right is the older version that amc cars used. It should work being they used the same motor.

About the brakes - I haven’t come across anyone adapting 11” brake drums to the Dana 53, that’s curious.

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1968 J2000 - AMC 327/T18/D20 (twin stick), stock D44s, 3" body lift, 35x12.50 Goodyear MTRs w/ Kevlar
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Topic author
Brly
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Re: '66 J3600 Brakes

Post by Brly »

Thanks for the confirmation 44bz. I know it will bolt up, just wasn't sure if it would function correctly.
Per my previous post, I was going to look into converting the rear drums to 11" if the 12" drums were shot. I don't see why you couldn't just bolt an 11" backing plate on, knock the studs out of the 12" drum and hub and put an 11" drum on. It appears that's what somebody has done already. I'll put new parts in the rear drums and run new brake lines everywhere.
Left the hub puller on the driver's side all night. Tried to tighten it up this morning and couldn't get any more on it. Maybe tomorrow I can get back to it to beat on it more.
Thanks,
Ben
1966 Jeep J3600 Gladiator - AMC 327/T18/D20
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tgreese
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Re: '66 J3600 Brakes

Post by tgreese »

The axle end pattern should be the same as other Jeep axles, so I'm not surprised that the 11" backing plates bolt on to the 53. The question then is whether the backing plate lines up in-and-out with the drum when you put the 11" drum on the 53 hub. If the shoes ride in the drum properly, you are ok. It would also be possible to put a shim between the axle end and backing plate to move the backing plates out toward the drums a bit, if needed.

11" brakes on the rear should be fine, since due to forward weight transfer the rear axle does little of the work when braking. The front axle can be converted to disks rather easily - there are lots of articles online about this. All the Jeep closed knuckle front axles are the same in this respect, so you can follow instructions for a CJ or Wagoneer or whatever. Several places sell kits, if you don't want to scrounge the parts yourself.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
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