Author Topic: 340 Engine Coolant Block Plug's  (Read 1060 times)

Offline daveh

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340 Engine Coolant Block Plug's
« on: September 12, 2016 - 10:44:17 am »
Hey guys,

I need 2 of the engine coolant block plugs for my 340 like in the link below.  I would prefer copper or stainless something that's not going to rust.  The two that I removed were pretty corroded.  I would just like to get something that's not going to corrode.  Thanks


Offline Mopar73340

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Re: 340 Engine Coolant Block Plug's
« Reply #1 on: September 12, 2016 - 04:46:18 pm »
You should be able to find something in brass that would not corrode as badly as steel. I use brass petcocks in mine just like in the radiator. Makes coolant changes easier.
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Offline 1 Wild R/T

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Re: 340 Engine Coolant Block Plug's
« Reply #2 on: September 12, 2016 - 06:02:42 pm »
Brass is usually a good choice, however since they are a softer metal they don't grip the block as hard as steel plugs & have been known  to pop out occasionally, usually when the engine is spinning big RPM's... High RPM's means the water pump is putting more pressure on there cooling system, it also means the tires are borderline to loosing traction..... Dump four gallons of water if front of the tires & life can get pretty exciting..... 

In the past guys would drill & tap holes & use retainer straps over the plugs, or There are brass/copper expanding plugs that lock in very securely...
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Offline EV2RTSE

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Re: 340 Engine Coolant Block Plug's
« Reply #3 on: September 13, 2016 - 10:59:31 am »
I just did a set in a 340 car that had been sitting for a long time. The one that had started leaking was between the engine and the transmission (of course) so I pulled the engine and replaced all of the plugs with brass. Chances are if you have one or two that are borderline, then there are likely more too. If you are concerned with the softer brass plugs popping out, another option would be to use thicker plugs than stock so that there is more contact area.