Radiator Drain Cock - Replacement

[AYM707]

Think we all agree ... that Toyota designed the FJ40 series correctly; but why did they make the radiator drain cock plastic???

Desperately looking for a solution that works ... need to plug the hole. What innovative solutions have you guys come up with?

 

[Bear]

contact
@ToyotaMatt

 

[ToyotaMatt]

Think we all agree ... that Toyota designed the FJ40 series correctly; but why did they make the radiator drain cock plastic???

Desperately looking for a solution that works ... need to plug the hole. What innovative solutions have you guys come up with?

They didn’t …

You have. A non-OEM toyota radatior drain plug and most likely a aftermarket radiator it self

This is why :

Genuine OEM SKUNK-WORKS Parts Radiator Drain Tube & Petcock F & 2F engines J.I.S. Tread Pitch FJ40, FJ55, FJ60 96431-03873-R - VintageTEqParts.com

Reproduction radiator drain tube & petcock 96431-03873 Correct JIS thread Pitch & Diameter Fits 1964-1987 F & 2F engines ,...

vintageteqparts.com

Originally it was a long cast iron tube with a brass pet-cock

They eventually rusted away to nothingness and leaked total failure..

I said that can’t happen any more and stopped that monkey business .

Marine grade Nickle alloy infused red brass will outlast man kind …

So we now can keep our good OEM radiators

 

[73FJ40]

One version of an OEM radiator drain:

 

[GA Architect]

Think we all agree ... that Toyota designed the FJ40 series correctly; but why did they make the radiator drain cock plastic???

Desperately looking for a solution that works ... need to plug the hole. What innovative solutions have you guys come up with?

FWIW: In the photo below, the zinc plated large six-sided extender is a Toyota OEM piece that comes with the 16400-49356 radiator. As for the plastic plug, it is off my CSF 2888 Radiator. This plastic plug is a M10x1.50 unit. The brass extenders are M10x1.50 extensions with allen head plugs.

 

[KennyBob]

FWIW: In the photo below, the zinc plated large six-sided extender is a Toyota OEM piece that comes with the 16400-49356 radiator. As for the plastic plug, it is off my CSF 2888 Radiator. This plastic plug is a M10x1.50 unit. The brass extenders are M10x1.25 extensions with allen head plugs.

View attachment 3203419

@GA Architect what are the M10x1.25 brass extensions for? I’ve got an aluminum radiator and I’m in need of an extension for it. Hoping those are them.

 

[GA Architect]

@GA Architect what are the M10x1.25 brass extensions for? I’ve got an aluminum radiator and I’m in need of an extension for it. Hoping those are them.

They are M10x1.50 adapters, see below:

Here is a 50MM extension: Pipe Fitting 1/8" NPT Female to Metric M10 M10X1.5 Male Brass Adapter N-#AC | eBay - https://www.ebay.com/itm/162531629821

Here is a 100MM extension: Fitting for Tooling Pipe to Metric 1/8" NPT to M10X1.5 Male 100mm Long | eBay - https://www.ebay.com/itm/202673046100

Also, I haven't taken a pic of my final extension pieces, but they have a slim nut screwed as far as possible. Then I soldered the nut-to-extension joint solid. That way I can use a rubber sealing washer between the extension & radiator....However, I'm still running my original extension, seen here ( Post #10 ).

 

[Green Bean]

The little plastic draincock makes a mess of things when you need to drain the radiator. The OEM design allows the coolant clear the radiator support and spill into a bucket.

 

[Fast Eddy]

Desperately looking for a solution that works ... need to plug the hole. What innovative solutions have you guys come up with?

Same threads as a spark plug.

 

[3_puppies]

Same threads as a spark plug.

X2 that is what I was going to say.

 

[locklaw]

Same threads as a spark plug.

Yup, I got a 40 out of Oz that likely had a spark plug in place of the petcock for at least 10 years based on the buildup in the plug and how much the threads had been corroded. It only started leaking once I replaced the spark plug with a NOS petcock and extension...

 

[Fast Eddy]

Oh, BTW, what's wrong with the plastic drain plug? They have always worked (as well as a spark plug) for me.

 

[middlecalf]

Which do you guys prefer, the hotter or cooler spark plugs?

 

[3_puppies]

Yup, I got a 40 out of Oz that likely had a spark plug in place of the petcock for at least 10 years based on the buildup in the plug and how much the threads had been corroded. It only started leaking once I replaced the spark plug with a NOS petcock and extension...

is it leaking at the rad where the extension screws in? it can be a weak area when extra torque is applied to remove the extension.
I always hold the extension when removing the drain so not to apply extra forces to the bottom of the rad, as I tore the bung out of a rad years ago, before knowing better
the pic @73FJ40 posted above shows the bung

 

[3_puppies]

Oh, BTW, what's wrong with the plastic drain plug? They have always worked (as well as a spark plug) for me.

the old ones weren't plastic
like the pic @73FJ40 posted above

 

[Fast Eddy]

the old ones weren't plastic
like the pic @73FJ40 posted above

Metal corrodes. Plastic does not. The plastic ones come out with finger pressure in my experience.

 

[acy76]

Bumping this in case it helps someone else, either in a pinch or permanently: I ran into this issue with an OE FJ55 radiator. Someone had removed the drain assembly already when I bought the truck.

I installed a spare/broken block drain in its place and it threaded in and has not leaked in heat cycle testing. See "before" photo here: New pig day - https://forum.ih8mud.com/threads/new-pig-day.1297194/post-14856199

It's only temporary unless it works.

These block drains are still readily available in several flavors from the dealer or vendors here for less than $20.

 

[2 Bees]

While in the process of getting my 72 FJ40 4-core radiator re-cored, found out the seat for the petcock had eroded. The petcock extension ( 2nd item in pic) into the radiator were a weird thread pitch. So down to the Hydraulic Shop, we found it's 3/8-19 British Pipe. We also found an adapter for converting male 3/8-19 BSPT tapered to female 3/8-18 NPT (bottom item in pic). First item in pic is for the TLC block drain petcock (Gas & Diesel) which is the same size as the radiator petcock extension.

You can get this adapter at most Hydraulic Shops. --- 7040-06-06 ---- female 3/8-18 NPT --- X --- male 3/8-19 BSPT Tapered (bottom item in pic)

 

[sleepycruiser]

Does anyone know the torque spec for the metal petcock in the bottom of the radiator?? Pulled my radiator out today to replace (going to be a few weeks bc I’m shipping my water pump out to have rebuilt).

 

[SteveH]

Does anyone know the torque spec for the metal petcock in the bottom of the radiator??

Finger tight, and then a little more until it doesn't leak. Don't reef it down! If you wipe it dry, and it doesn't leak at full operating temp (and pressure), you're done.