Coolant Temperature Probe Ports Across The Years

[keithb7]

The below photo shows two cylinder heads that I own. Left is a 1949 Canadian 25” 218 ci. Right a ‘54 Canadian 25” 228 ci.  The 228 engine was removed recently from my ‘38 Plymouth. Neither head has the correct size pipe threads for the original ‘38 temperature probe port for the dash gauge. (⅜ pipe I suspect)
 

I think the 228 head Has ¼ pipe. (Seen on right). The 218 has ½” pipe. I think. I don’t have tools to check pipe threads.  I'll just head down to the store and start by comparing pipe adaptors and bring some home.

Option 1:

Thinking I’ll drill out and tap the 226 1/4 pipe head port to fit the ‘38 temp probe.  Anyone have of any concerns with me doing that?

 

Option 2.

The 218 head with ½ pipe port. I source a pipe adapter and drop it down to ⅜ pipe. 

 

One of these heads will go back on my pulled 228 engine. Then back into my ‘38 Ply. I am thinking the 218 and the 228 heads have the exact same cc sized combustion chamber. Therefore there is no compression gain to be had, if I put the 218 head on.  Sadly. Would be cool if it did. 

Comments or concerns are welcome.  Thx. Keith

 

PS:

As a side note, my 228 3 3/8” bore engine will be bored over to 3 7/16” to net me a 237 ci USA Desoto engine! That alone will net me some increased compression. (Same stroke larger bore)?

 

 

Edited January 3, 2021 by keithb7

[Merle Coggins]

A 1/2 X 3/8 pipe reducer will work fine and would be much easier. 

[JBNeal]

Agreed...might be listed under temperature gauge reducing bushing...I needed one years ago, bought a universal temperature gauge at Western Auto as it had a variety of bushings included, still have the gauge in the packaging...nowadays, ya might be able to locate exactly what ya need and have it delivered to your doorstep 

[Sniper]

I think either way will work, my local hardware store has that reducer bushing in stock, my be an option for you there.

[keithb7]

Back from the store. ½ pipe reduced to ⅜. Bingo.  The 218 head shall be used. 
 

Thanks folks.  Always a pleasure doin’ business here. 
 

 

 

[desoto1939]

The correct adapter to screw into the side of the head for the temperture bulb is called a glandnut. It has the hole for the bulb at the end of the temp guage to slid into the opening of the gland hut and then the threaded nut end of the  temp gage bulb is treaded onto the glad nut.  What you need is the inner thread and size of the hole of the head to match up and then the opening and threads onthe temp gage blub outer nut to also match up

 

The nut is called a glandnut usually made of brass.

Edited January 4, 2021 by desoto1939

[keithb7]

After Richard’s comments (thanks @desoto1939)  I poked around in my 265 engine compartment.  Pic seen.  
 

The ‘38 temp probe in my pipe adaptor as seen in the pic above, does thread in nicely  However looking again, it bottoms out.  Indicating the probe is not a tapered pipe thread.  Its some type of straight thread but same tpi pitch.  Yet the ½” pipe adaptor tapers nicely into my head. Hmm. Richard is onto it. A special adaptor. Perhaps before I pay $40 shipping for and $30 for a special adaptor, I’ll try loading up the sensor threads with silicone tape. See if I can get it to bite in and seal. 
 

 

Edited January 3, 2021 by keithb7

[Jerry Roberts]

The gland nut has a tapered seat inside for the ether bulb . 

[Merle Coggins]

Ahh, yes... I didn't realize that you didn't have the proper adapter to go with the gauge. I thought you were saying that the gauge fitting was 3/8" NPT, but apparently you don't have that essential piece. As was mentioned by others, that fitting actually has a seat inside for the bulb flange to seal against. The swivel nut (gland nut) will then squeeze that flange against the seat to seal. If you use a regular reducer bushing there is no seal and coolant will flow right past the bulb and you'll have a major leak. 

Edited January 4, 2021 by Merle Coggins

[keithb7]

This insanity is slowing killing my ambition for this hobby. This is not sustainable. Who's to blame for these ridiculous freight charges?

It's frustrating. I will not be ordering this part at this cost. I will find a way to build one or source a local used one.

 

 

[Merle Coggins]

There has to be more economical ways to ship items across the border other than First Class mail. Although you may not get tracking on cheaper shipping options.

[61spit]

Keith,

 

Is this the same size you need? I don't know what shipping would be from them but the cost is considerably less for the part itself.

 

https://www.summitracing.com/parts/mor-63645/applications

[desoto1939]

I would write to Mike at MoparPro to get a true shipping quote.  Ebay is just throwing out a number on shipping.

 

Write to him to get  trure shipping charge.

 

Rich Hartung

[keithb7]

I did @desoto1939 I have been in touch with Mike at Mopar Pro. He seems like a good guy. Not his fault about all the added fees and charges to get it to my door. At the end of the day it's beyond my level of tolerance for 1 simple bushing. There is a limit to the amount of cash I am willing to toss into the wind to have a properly working temp gauge. I may plug the hole in the head again for now. Some day another seized flathead Mopar engine will appear locally. I'll get one...Someday. I'm maintaining a driver car here. Not a restoration.

 

@61spit that does look like a decent alternative option.  Yet again, the freight, exchange costs, and additional handling fees for each parcel by Fed-Ex makes my head spin. Summit does not offer basic USPS ground mail as an option.

 

Sorry to turn this thread into a whining session about vintage Mopar parts costs. I'll quietly move on. 

 

 

*Edit to update that a local parts supplier can get me that Morso bushing for $14.94 Canadian ($12 US funds all-in) No freight costs. 6-8 weeks delivery. Good thing I am not in a hurry. Lol.  I will order it and give it a try.

Edited February 3, 2021 by keithb7

[Sam Buchanan]

On 1/3/2021 at 2:06 PM, keithb7 said:

 

 

Edited February 3, 2021 by Sam Buchanan

[desoto1939]

Do you know anyone in the states that the itms canbe shipped to and then have them ship it directly to you. Might be cheaper that way. I see people sell items on ebay from canada and the shipping is not that high as compared to Mikes estimated shipping fees.  The item canbfit into a bubble envelope not that big of an item.

 

I know shipping costs have gone thru the roof but I send items to europe and have not paid that type of fee and have sent boxes with items in them.

 

Rich Hartung

[Eneto-55]

On 1/3/2021 at 3:06 PM, keithb7 said:

The below photo shows two cylinder heads that I own. Left is a 1949 Canadian 25” 218 ci. Right a ‘54 Canadian 25” 228 ci.  The 228 engine was removed recently from my ‘38 Plymouth. Neither head has the correct size pipe threads for the original ‘38 temperature probe port for the dash gauge. (⅜ pipe I suspect)
 

I think the 228 head Has ¼ pipe. (Seen on right). The 218 has ½” pipe. I think. I don’t have tools to check pipe threads.  I'll just head down to the store and start by comparing pipe adaptors and bring some home.

Option 1:

Thinking I’ll drill out and tap the 226 1/4 pipe head port to fit the ‘38 temp probe.  Anyone have of any concerns with me doing that?

 

Option 2.

The 218 head with ½ pipe port. I source a pipe adapter and drop it down to ⅜ pipe. 

 

One of these heads will go back on my pulled 228 engine. Then back into my ‘38 Ply. I am thinking the 218 and the 228 heads have the exact same cc sized combustion chamber. Therefore there is no compression gain to be had, if I put the 218 head on.  Sadly. Would be cool if it did. 

Comments or concerns are welcome.  Thx. Keith

 

PS:

As a side note, my 228 3 3/8” bore engine will be bored over to 3 7/16” to net me a 237 ci USA Desoto engine! That alone will net me some increased compression. (Same stroke larger bore)?

 

 

Is the temp sender on the right in your photo (from the 54) an electric one?  (It looks like a terminal on the top of the sender, but I can't tell for sure.)  Have you pursued drilling it out & tapping?  Curious because I have a 55 model Plymouth engine (230) in my 46 P15, and it has the smaller hole, for an electric sender.  I've thought of having it drilled & tapped as you suggested, but haven't pulled it back off to do that.  (I also have a 218 head off of a 49 1st series P15, but had put a lot of work into the later model head before I realized this difference.  So hate to start over with the other one.)

[keithb7]

@Eneto-55The temp probe on the right is electric. That 25" engine came out of a '54 Canadian Dodge. 228 ci. That engine resides in my '38 Ply car. That engine is out now, torn down for rebuild. That head has the slight bulge cast into it at the front to accommodate the water passages for the by-pass type water pump. I want to re-use that head. My plan is to drill and tap it for ½" NPT, so I can utilize the stock temperature gauge system in my '38 Ply car. 

 

The head on the left is spare head that I have from a 1948 25" Canadian Dodge.  218 CI engine.  It is indeed tapped for ½" NPT. However that head does not have the cooling passage for the by-pass water pump.  Additionally, neither head does me any good without the gland nut that I need.

 

Oh the joys of swapping major components.

[ccudahy]

Would a REDUCING BUSHING WORK? The internal threads don't go all the way thru to create a stop for the temperature bulb.

 

 

 

 

 

Edited February 3, 2021 by ccudahy

[kencombs]

I just took a look at that part on the bay.  It ships free to me.  Also just picked a postal code in western Canada at random and it appears that it should ship from me to you for less than 15 bucks.   USPS first class package weighing 6 ounces (my guess at the weight).  Maybe it would work to have a member order and reship, as it looks like there is a lot of seller overhead in the ship price.  Not knocking him, it does take time and material to handle items out of the ordinary.

[keithb7]

Thanks for the ideas by many Mopar friends here. The offer to re-ship parts to me  from a member inside the USA, is gracious. However, a fellow member here has come forward with a spare gland nut to drop in the mail to me. All I must do is "pay-it-forward" someday. Indeed I will, for one good turn deserves another!

[Sniper]

Well, dang.  I have the gland nut from the core 230 I bought I was going to offer up.  If anyone else needs it let me know, otherwise I will keep it safe till the day arrives that's it's actually worth it's weight in gold, lol.

[sidevalvepete]

Neil Riddle in Washington has a couple available for $24.50. Not sure what shipping is from there but have always found him a good bloke to deal with. Ebay is Seaplym. Listing number:

                  313408471222

[keithb7]

Following-up to close out this thread. Thank you to a couple of outstanding members here who “pay it forward” I secured the proper gland nut. 
 

Tonight I took my head to my local friend’s garage. He used his machinery to drill and tap the probe hole to ½” NPT. Now we should have a properly functioning bourdon tube system from 1938, in my 1954 engine. 
 

I too shall pay it forward when the opportunity arises. Thanks. 

 

 

Edited March 5, 2021 by keithb7

[keithb7]

 

 

Edited March 5, 2021 by keithb7