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| | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | Finally got the head off my 503. HRL was kind enough to add Sodium Silicate(water glass) to the water since combustion air leaked into the water, due to some true genius not tightening all the head bolts. We(HRL and I) got it home from Arkansas, OK.
Started leaking again, so decided to do a valve job and replace the head gasket. Tried to get the head off, wouldn't move, tried lifting, wouldn't move again, added shop air to 3 jugs, no joy, added shop air to all 6 jugs-that is 150 psi times 4 9/16" bore x 6 jugs, tried lifting more, finally tried lifting at various ends of head, got air leak so I knew I was making progress, finally got it off after careful lifting and relaxing many times over the course of a month or so.
Head and block look OK. Going to mill the head 60 or 90 thousanths, since the compression ratio is only 6.5 to one. The moral of the story, is be careful with the use of Sodium Silicate and how long you leave it in. I doubt the addition of antifreeze made the difference.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Feb 2004 Posts: 29,777 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,777 | Hmmmm- - - - -good to know! That stuff hardens into a glass-like substance with a melting point up around 700+ degrees when exposed to combustion heat. Apparently it also makes a pretty good glue! I've heard of oldtimers loosening the head bolts a turn or so and driving around the block a few times with repeated full throttle applications to loosen up a stuck head. Flathead Ford V8's with studs instead of head bolts were notorious for getting the heads stuck tight, just due to rust bonding the studs and the head together, no water glass needed!
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | I thought of that, after I found how hard to get off, too late then.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Feb 2015 Posts: 44 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2015 Posts: 44 | Hey Ed. Ron here. Not trying to hijack this thread, but I thought since you're on here maybe you could help me.My truck is a 54 930 fire truck with the 503 too. I removed the pump assembly, but the pump was holding the disc brake/ parking brake assembly in place. What did the normal non-fire truck have to hold the parking brake assembly in place or what can I do? Thanks, Ron | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | The pump [censored]'y was already removed from my truck when I got it. There is a Tru-Stop disc brake on the back of the 5 speed. I cannot quite picture your "pump holding the brake assembly in place." I have replaced previous pumps with a 'Brownie' and found a True-stop that fits. It is always best to have the brake on the last transmission.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Feb 2015 Posts: 44 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2015 Posts: 44 | | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | I presume you have 'juice' brakes, can you just disassemble the pump and use the brake part only? Unless you want a brownie for road speed.
I don't know if the brake will fit on the back of the 5 speed, that is where mine is.
Ed
Last edited by EdPruss; 11/24/2016 6:41 PM.
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
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