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| | | | Joined: Aug 2021 Posts: 3 Moderated | | Moderated Joined: Aug 2021 Posts: 3 | So we pulled two leaking freeze plugs out of our original 228 today. (1946 gmc ec152)
We then spent over an hour with the garden hose, flushing globs of dirt and rust from the block. It’s now running clean water. But when I reach a finger inside the freeze plug holes, I can feel what seems to be a rod or line, and it feels loose. I’m guessing oil line? Anyone have any idea what this might be? I’ve looked all over but can’t find any info online about the inside of a 228. Would appreciate any insight. | | | | | Joined: Dec 2015 Posts: 2,062 Big Bolt Forum Moderator | | Big Bolt Forum Moderator Joined: Dec 2015 Posts: 2,062 | welcome to the site! You may not get an answer here, as this is the welcome centre forum, where folks introduce themselves and their truck. Not a lot of questions get answered here. Your question would be better answered in the engine shop area. | | | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 | Depending on where your poking it very well could be an oil line. You don’t want it to come loose. Our engine experts will be along soon.
Martin
'62 Chevy C-10 Stepside Shortbed (Restomod in progress)
'47 Chevy 3100 5 Window (long term project)
‘65 Chevy Biscayne (Emily)
‘39 Dodge Business Coupe (Clarence)
“I fought the law and the law won" now I are a retired one!
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USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
| | | | | Joined: Feb 2000 Posts: 5,194 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,194 | Shouldn't be any oil lines in a coolant passage, could be a loose wire someone lost in there while poking out dirt. Maybe they didn't pull the freeze plugs like you did and used wire to poke around and lost it. | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | There are bunches of fiber optic borescopes available on Ebay for ridiculously low prices that will let you take a detailed look inside that water jacket. One of the ones I use regularly has a 5MM probe 24" long, a right angle mirror attachment, and a variable intensity light built in that lets me look at the rifling of gun barrels all the way down to .22 caliber, and also look inside engine cylinders. It paid for itself the first time I used it!
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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| | | | | Joined: Feb 2016 Posts: 148 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 148 | I'm going to guess it's from the factory. Mild steel wires were commonly used to suspend and hold the cores in place when casting the block. These wires were "almost" always removed by the foundry before machining the block.
Last edited by DavidBraley; 08/05/2021 1:38 AM. Reason: Spelling
-David
1953 2-Ton GMC
I'm a machinist... because engineers need heroes too.
| | | | | Joined: Feb 2020 Posts: 47 'Bolter | | 'Bolter Joined: Feb 2020 Posts: 47 | I've had 5 GMC engines apart recently, and all had wire rods in them from the factory. Part of the casting process. No worries.
Joe
just retired and finally making headway on my project truck. 1940 GMC AC152.
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | LD,
Make sure to use a rod or large wire to clean out drain and petcock holes of trash and rust that tends to accumulate there.
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: Oct 2018 Posts: 118 'Bolter | | 'Bolter Joined: Oct 2018 Posts: 118 | Have seen the same thing on several GMC inline 6 engines. The wire is about the same diameter as a coat hanger. As mentioned, probably used in making the sand core.
The oil line to the cylinder head on the GMC is external.
Best Regards... | | | | | Joined: Dec 2018 Posts: 2,450 'Bolter | | 'Bolter Joined: Dec 2018 Posts: 2,450 | LDJones Remember those sixties mopars that the coolant looked like chocolate milk?? That was from core wire in the block, | | | | | Joined: Aug 2021 Posts: 3 Moderated | | Moderated Joined: Aug 2021 Posts: 3 | Thank you everyone, I’m feeling a little better about the mystery wires... | | |
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