503 engine

[66Submarine]

The 22.5" was/is the tubeless equivalent to 20" tube type.

[C10 - C90 Bill]

Originally Posted by 66Submarine

The 22.5" was/is the tubeless equivalent to 20" tube type.

OK, there is my limited wheel knowledge showing, lol.

Especially with the newer stuff...

Edit: Just did a little research on the subject and there is a lot out there !!

Bill

[Firefool]

Drove truck home from shop sunday, it ran well, stopped good. First time its moved itself in who knows how long. Should be a soild rig, just need to do a ton of cleaning on it.

[bob_o]

Very cool. Thanks for bringing this old beast back from the dead!

[Mr Chevorlet]

Very nice, That was a big motor, glad i looked at your thread. Love the old fire trucks

[Firefool]

Guys I have been driving the truck and it is doing great, I did put some 22.5 radial tires on it....... any one have a interest in the 9X20 Tube type split rings? Tires are dry but have alot of tread on them be great for a farm or grain truck.

[_Ogre]

nice save on the 503 motor
i like the oddball stuff
that push rod is humongous

[edpruss]

I just got a 503 with 26M miles on it, do you know if there any high compression(propane) Pistons available for them?

Come across any spare water pumps?

Thanks, Ed
Posted via Mobile Device

[56_firetruck]

I have a 56 GMC 630 that was a tanker firetruck and I'm needing a few parts can anyone guide me in a direction? I'm needing brakes and I have a few questions

[55 gmc 630]

Did you find any parts/info you needed? I Just acquired and old 55 gmc 630 w/the 503 and am just learning about it's bits.

[56_firetruck]

No I haven't found anything yet. Can you get some pictures of the Driveshaft I'm having to make one from scratch and I need some guidance?

[55 gmc 630]

[IMG][/IMG]I can... tomorrow. I am not familiar at all with how these forums work... like how to upload pics but I will attempt it. Mine is a 5spd manual with a "brownie box" right behind it(20 speeds) so my set-up may be different than yours- like if you have 2spd rear. I might be interested in any pics of vacuum lines related to the governor. I will see if i can add an image w/this post just as test---oh, asks for url... i have to figure that one out. more later

[C10 - C90 Bill]

If no one jumps in here also check with some of the guys at Stovebolt.com, the ATHS site as well as Just Old Trucks. There are a lot of old time mechanics on those sites and they could probably help with parts too.

[cff]

I have a 54 630 with a 503 and 15000 miles. It was a tanker fire truck and I have taken the tank out. The driveshaft has a pretty cool mechanical disc brake setup for the emergency brake but the disc is mounted to the main fire water pump. When I took the pump out I'm not sure how to mount the disc for the emergency brake. Has anyone done this. I don't want to leave the pump in for a number of reasons. One - the pump sticks up above the frame rails, so I would have to raise the bed floor. Two - I don't want to have to keep maintaining the pump. Three - It's heavy. I don't want any extra weight.
Thanks in advance for any ideas.

[55 gmc 630]

My '55 , as i am told, was a fire truck tanker also... but now has a flatbed. Mine has the break thing on the driveshaft no pump remains so not sure of that set-up. I have not run truck much---got it trailered here(drove it on and off) and it's been sitting 2 months so not real familiar with it other than plugs and wires and such. Mine has a 5spd w/4 spd brownie box. Look in my photo folder- there are a bunch of pics i took for guy with driveshaft questions- see if you get any answers from them. I would have to look more closely at my set-up to tell you anything. I'd love to see pics of the pump you speak of and controls. https://www.youtube.com/watch?v=igIPSk0qqCQ . https://www.youtube.com/watch?v=1ng3QHwOAik

[1956630]

It's been some time since I've been on the site, I could not figure out how to sign in so I have a new user name. However things have gotten crazy in life I'm considering selling my GMC 630. Where do you guys recommend trying to sell a unit like this? Only would allow it to go to a good home it's just too cool and clean to see it tore up.

Thanks Joe

[cff]

Hey Joe. I might be interested in your GMC 630. Can you send me some pics? PM me and I can send you my email address or phone number to text me. Thanks, Ron.

[1956630]

Please note that you must be a supporting member to post classified items. This includes but is not limited to What Its Worth, Want To Buy, Want To Trade, and For Sale. Please consider supporting the forum by subscribing. Further information on the subscription levels available are located here

If you need any further assistance with that please contact any Admin for help.

[jjzepplin]

Noooo!