Freeze plugs

[savageskaterkid]

I know it seems like a simple question and all, and a search should have found this, but with such a broad search, it didn't help. I need to know what size the freeze plugs are in the block. For some reason my rebuild kit didn't come with plugs, and for some other reason, autozone can't cross reference a size. I need to the sizes ASAP. I think there is 2-3 diffrent sized plugs in the block alone.

[BRAAP]

You can call a local automotive machine shop and tell them you need CORE plugs or SOFT plugs or EXPANSION plugs for your Datsun L-series,. Tell them what the block is, i.e. L-24, L-26, or L-28 and what year the block is and they will set you up, (It really doesn’t matter what year or even which engine it is as the Pioneer expansion plug sets are the same fro ALL L-6 engines.) You have the option of BRASS or STEEL. Brass is more expensive, but if you plan to not rebuild the engine for at least 100,000 miles, then go with the BRASS, otherwise the steel CORE plugs are just fine. If they are having a hard time finding them for you, give them one of these Pioneer part number…

 

Steel plugs PE-132

Brass plugs PE-132-B

 

Or you could just order them through us…, but only if you promise to NEVER call them freeze plugs ever again…

 

The sizes are 35mm, 40mm, and 50mm. You'll know which is which, (one under the fornt cover, one under the bellhousing and the others are visible on the both sides of the block, 35mm).

 

 

Ruschmotorsports@hotmail.com

[Tony D]

I see someone else has the same aversion to the 'shadetree' terminology as I do...

 

LOL

 

Are you sure we aren't somehow related? LOL

 

Tip: Seal the edges with something like aviation sealer, etc before driving them in. I've also known people to use 1/2 tube of alumaseal in every engine after assembly and initial start (Ford and Volvo being two of them...) to preclude any weeping from unclean or nicked core plug bores (amongst other things).

[savageskaterkid]

I know the whole core plug vs. freeze plug thing. Actually read a nice discussion on here about it awhile back. I run into the problem alot when saying core plug and everybody thinks your an idiot. So I just said freeze plug thinking as though the majority of people still see it as a freeze plug that blows out the block when the motor freezes.

 

I just need the plugs ASAP, like tommorrow, so I cannot order. I was at autozone today, they do not have brass plugs, they have RUBBER plugs-does that seem right, I've never heard of rubber plugs.

[BRAAP]

The rubber plugs are ONLY a temporary fix to get the car off the side of the road and to the shop/home for a proper fix, (or back home from the track when one blows out, as in Garrets case)! That is the only purpose of the rubber plugs.

 

Good luck,

Paul

[savageskaterkid]

BRAAP, I do not doubt a single word you say, so I'm leaning towards autozone being wrong on this one. But then again, everybody has a time where they miss something-Is it 35mm 40mm and 50mm, at autozone there was not 50mm, but a 47mm, which is a small diffrence.

[BRAAP]

I am pretty sure that info is correct, though not 100% sure. My literature says 35mm, 40mm and 50mm are used on the blocks and I just checked an L-24 and a F-54 L-28 block in the shop and they both have 35mm plugs in the sides, a 40mm in the front and a 50mm in the back. Nissan may have used a 47mm at some point in the blocks, but none of my literature nor the blocks I have on hand have a 47mm plug in them.

 

Hope that helps.

 

Here is the 50mm plug in the back of the block under the bell housing…

 

[lbhsbZ]

Freeze plugs is better than frost plugs....I've heard that one quite a bit.

[BRAAP]

Freeze plugs blah blah blah ... frost plugs....blah blah blah blah...

 

 

One more wise crack… just ONE MORE Alice, and “POW” right to the moon…

 

 

 

Just kiddin, really..

[Ledphoot]

I have to admit... although I hate too. I have been a tech for many years and have extensive training and I have always heard them called freeze plugs or occasionally expansion plugs... Maybe it is a term used in different parts of the US ? Oh well... it all sounds good to me!

[datsun79z]

The term "Freeze Plug" is thought to have originated in the nether regions of Antartica. Originally kegs of beer when left outside overnight would freeze thus causing the keg to split and sometimes explode. A genious of a fellow came up with the idea of using a "bung" or "Freeze Plug" in the side of the keg. As the beer became colder and started to freeze the "Bung" or "Freeze Plug" would loosen and the beer would spill. There was a massive quanity of beer available in Antartica at this time and plenty of cold to go around. This resulted in much lost/spilt beer. Some of the locals not wanting to spend thier hard earned money would pay close attention to the temp. drop and take advantage of what might have been wasted brew. Eventually they put on weight and the term Freeze Plug was changed to, you guessed it, Expansion Plug.

[datsun79z]

This true. Really.

[Tony D]

I run into the problem alot when saying core plug and everybody thinks your an idiot.

 

Correction: Slack-Jawed Shade-Tree Gomers think you're an idiot. People who understand casting, and people who have had prefessional schooling in Automotive Technology will understand exactly what they are when you say 'core plugs'.

 

"Freeze Plugs" is a misnomer based on someone making the anecdotal observation that sometimes those plugs will pop out of the coolant in happens to freeze. Think about this: that ice expands throughout the whole jacket---I have seen PLENTY of cracked blocks where NOT ONE PLUG WAS DISPLACED!

 

The plugs are there for the purpose of removing casting sand, providing access to something during machining, or (As the correct name suggests) holding cores in place during casting.

 

If they are 'freeze plugs' then why are they on the back of a Nissan Intake Manifold?

 

Reason: They need a hole there to support the CORE of the plenum while casting it!

 

Core Plugs, Soft Plugs, Welsh Plugs. I can give you a reason catagorically why those are a correct terminology based on engineering facts.

 

I can show you countless reasons through failures why they are not 'Freeze Plugs'... Urban Legend and Gomer Myth, perpetuated by the uninformed and uneducated---if it seems like everybody is looking at you like an idiot, take the time to educate them---ignorance is a terrible thing to leave unrectified.

 

If they argue, consider the thought you may not be getting great service buying stuff there...

[SUNMASTER]

Hi there

 

Here in South Africa we call them welsch plugs.

 

freeze plug = welsch plug = core plug

http://spriteparts.com.au/welsch.htm

[BRAAP]

I recently received a PM and felt it was relevant to post publicly. Here is that cut and paste with the question and my response, though the name was changed for privacy.

 

remember we talked about freeze plugs and what they are for? you say to drain sand out of the cast iron block....

 

 

well question....

 

if they arent to prevent the block for cracking' date=' then why are they in alluminum heads and al blocks???[/quote']

 

For the same reason. When Aluminum heads, blocks, manifolds, etc, are cast, the same process is used. The only difference is the material being poured into the molds, Aluminum vs Iron. Those core holes are where the foundry drains the sand out of the block or head no matter what material they are cast with, then they plug those holes with metal plugs. Those same holes are also where the internal core is supported if an internal core is utilized, such as with a cylinder head, engine block, intake manifold. Aluminum will crack just as iron does, though I think cast aluminum is a little more flexible therefore a little more forgiving when water freezes within, though Aluminum heads/blocks will still freeze break if water freezes in it.

Tony D. brought up something I totally forgot about. Look at the end of the plenum of a stock EFI manifold. You’ll see a 35mm core plug, exact same plug as used on the blocks, yet there is no water/coolant running through the manifold. No reason for that plug other than to support the inner core a specific distance from the outer core, (this establishes the manifolds wall thickness), and also serves as another location from which to drain the sand out of the manifold after it is cast, just as Tony said.

 

I’ve included a couple of online references as well that should help explain these plugs a little better. .

 

Hope that helps.

 

http://www.econofix.com/frezplug.html

 

http://en.wikipedia.org/wiki/Freeze_plug

 

http://www.austin7.org/core_plugs.htm

[bubbleguinea]

so heres another question........i do not understand----

 

the way water expansion will work, is it will freeze and take the easiest way out...this way is the freeze plug....not cracking iron........

 

if you drill a safe with a 2 inch hole at the top, fill it to the brim with water, and freeze the safe, the water will expand and dribble out the top, and freeze....the safe wont crack!!!

 

so if you put a press fit plug in that same hole, freeze it , the frozen water will take the path of least resistance!!!

 

is that not correct????

 

ive got people at work (Main Auto Parts) who will argue left and right saying the CORRECT term is FREEZE PLUGS...and im realying all this information to them, but they still insist about the physical properties of water when it freezes.....

[nbesheer]

Well this might be coming out of left field but as far as I know when water freezes it freezes from the top down. so the surface is frozen then I suppose when the rest freezes under it I pushes ice up and not water, where as water can flow out of a hole sheets of ice might not.

[OlderThanMe]

I say if your motor does get to that freezing temperature it is much more likely to bust a wimpy little rubber radiator hose than the iron block...

[BRAAP]

This more of a rant against the close mindedness of people in paid informational job positions that should not be in those positions. Thank you for allowing me to get this off my chest.

 

 

Don’t take this wrong Bubble, it is not directed at you. It is truly frustrating to spend so much time and effort trying to educate and help those willing to learn and understand, only to have it get thrown back up and questioned, YET again! You are caught between what is written here on Hybrid and the close minded Slack-Jawed Shade-Tree Gomers, parts counter guys you work with. Those guys arguing to the left and right about this are obviously NOT engineers, machinists, engine builders, or tuners, etc., (the rest was edited out as it really just reflected my feelings toward the blatant close-mindedness of some individuals. If only we can get them to broaden their minds little more eh?…) ARRGHHH...

 

I encourage those same guys at the “Main Auto Parts” to read this thread and I hope they not only can, but that they will in deed comprehend what is being posted here, including the links which also explain exactly what we are trying to convey, (wiki-pedia is awesome). It would be interesting to hear from them as they explain where and how they got their misinformation about “freeze plugs” and why they still want to believe the myth even after being shown factual data that unequivocally does NOT support their argument? I then encourage those same nay sayers to go to ANY automotive machine shop and ask the owner and workers how come those freeze plugs aren’t doing their jobs with so many FREEZE broken blocks and heads lying around? Show them the picture of the block pictured below and then have them explain how and why the freeze plugs failed to do their job! I’ll post why, (doubt it will do much good). Because they ARE CORE plugs, NOT freeze plugs! The only protection ANY and ALL cylinder blocks and heads have against freeze breakage is proper antifreeze/coolant maintenance! PERIOD!!!

Have these guys visit a foundry that casts metal parts and ask the guys that actually do that for a living about core plugs, and then ask some engineers about metallurgy and the properties of water, especially in its solid stated. If they choose to keep a closed mind, so be it. I personally am done with beating my head against the wall on this subject. If a closed minded parts counter guy swears that they are freeze plugs, and are only to protect the block, then you can be absolutely sure that parts store will be flagged as a place not to support.

 

 

In your example of the safe, if you fill it with water, the safe will still bust. Water expands in ALL directions when it freezes. As it does freeze and expand, any liquid water that is near the small hole will be expelled, but the safe will still break. Another example, a glass of water. The entire top of a drinking glass is open which in theory allows for expansion, but the expanding ice will still bust the glass, because ice expands in ALL directions, not just up the and out the available opening. The same is true in engines. The iron and aluminum will flex, but only to a certain point, and then it just separates, ie. cracks.

 

Paul… Out!

 

[Tony D]

"the way water expansion will work, is it will freeze and take the easiest way out...this way is the freeze plug....not cracking iron........"

 

No, the way water expansion works is hydraulic pressure, it's equal throughout the system IF the water is fluid...

 

A "Relief Valve" only works in a FLUID system. When it becomes solid, it expands against the other solids and the cast iron will break.

 

Anybody arguing this point is simply ignoring the obvious question I have always posed: If their Function is NOT for holding CORES in place (hence the name "core plugs") then what in the world is the liquid that is going to Freeze in the INTAKE MANIFOLD PLENUM???

 

In this case, it is a Core Plug Hole. And you Insert a Welsch Plug into it, where it plugs the core plug hole.

 

There is a logical, engineering argument AGAINST the term 'Freeze Plug', and and equally strong engineering argument (up to and including Foundry Practices for over 100 years) for the term "Core Plugs".

 

The people at the local generic auto parts store have how many hours of engineering coursework behind them? How many years actually working in the automotive business?

 

Like I have said repeatedly: 'Just because you screwed your sister for 17 years doesn't mean it's right!'

 

As this subject is heading towards the 'beating the dead horse' realm... I will add the obligatory note: The difference between simply being ignorant, and being stupid is refusing to see the facts. When the facts are presented, and you refuse to change your incorrect stance, you cross over from the realm of the merely ignorant, to the stupid. Not knowing is one thing, knowing better yet still clinging to the old terminology is plainly stupid. Period.