Mk II External Oil Cooler drain plug

Dancin

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Does anyone know what size socket the drain plug on factor Mk II external oil cooler takes (SAE or metric). Appears to be close to 34 MM or 1 5/16?

Thanks,
Dan
 

Austin Healer

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1 5/16 fits the closest, but it is likely a BSF/Whitworth size as all oil and fuel line fittings on English cars are BSB (British standard brass) thread. these use BSF/Whitworth wrenches that are based on the fitting diameter and not the size of the head. The special bolts for the oil filter adapters are 13/16 Whitworth!

There are NO metric fasteners on any English car before 1973.

You know why the French invented metric? It makes it sound so much longer than 6 inches......
 

65beam

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1 5/16 fits the closest, but it is likely a BSF/Whitworth size as all oil and fuel line fittings on English cars are BSB (British standard brass) thread. these use BSF/Whitworth wrenches that are based on the fitting diameter and not the size of the head. The special bolts for the oil filter adapters are 13/16 Whitworth!

There are NO metric fasteners on any English car before 1973.

You know why the French invented metric? It makes it sound so much longer than 6 inches......
The MK 2 Tiger had a 15/16 X 7/8 wrench included in the tool kit. It was intended to be for use on the oil cooler fittings.
 

Austin Healer

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The MK 2 Tiger had a 15/16 X 7/8 wrench included in the tool kit. It was intended to be for use on the oil cooler fittings.
The question was for the drain on the cooler, NOT the hoses... The hose fittings are SAE because they were made from US sourced parts. The adapters and the oil cooler were British made and because of that have BSF/Whitworth sized fasteners..... (adapter bolts/oil cooler drain). The fuel line fittings at the OE SU pump and for the oil pressure line also are BSB thread and use BSF/Whitworth wrenches.

I own a Mk2 Tiger.
 

65beam

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The question was for the drain on the cooler, NOT the hoses... The hose fittings are SAE because they were made from US sourced parts. The adapters and the oil cooler were British made and because of that have BSF/Whitworth sized fasteners..... (adapter bolts/oil cooler drain). The fuel line fittings at the OE SU pump and for the oil pressure line also are BSB thread and use BSF/Whitworth wrenches.

I own a Mk2 Tiger.
Maybe the intention was to use the King Dick adjustable wrench. It's standard. Whitworth and metric. Or just use a plain old crescent wrench. Did you ever notice that the Tiger oil cooler is basically two series 5 Alpine coolers double stacked?
 

Austin Healer

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The adjustable wrench is nowhere hear big enough for the Mk2 oil cooler drain plug. As for the alpine cooler vs. the Tiger cooler... the diameter of the cross tubes are different. The Tiger cooler uses 1/2" i.d tubing and the Alpine is 3/4" tubing. The construction is also totally different. Alpine oil cooler tubes are soldered into the adapters for the hose fittings which are also designed for larger diameter hose fittings. Tiger oil coolers are brazed together and virtually impossible to get apart. The Tiger oil cooler also has a drain and spring loaded bypass that the Alpine doesn't have.

The Mk2 supplemental wrench only fits the fittings at the oil cooler. The other hose fittings are all 3/4" AF (SAE)

I have a crash damaged Mk2 oil cooler (it doesn't leak). I wanted to take it apart to either repair or replace the cross tubes. I had thought about using Alpine cross tubes as I have several. That's when I discovered the difference in tube diameter. I ended up just standing on the oil cooler which straightened it out... Now all I have to do is pull all the cooling wires out again to make it pretty... as it's a spare, I'm in no hurry.
 

65beam

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The adjustable wrench is nowhere hear big enough for the Mk2 oil cooler drain plug. As for the alpine cooler vs. the Tiger cooler... the diameter of the cross tubes are different. The Tiger cooler uses 1/2" i.d tubing and the Alpine is 3/4" tubing. The construction is also totally different. Alpine oil cooler tubes are soldered into the adapters for the hose fittings which are also designed for larger diameter hose fittings. Tiger oil coolers are brazed together and virtually impossible to get apart. The Tiger oil cooler also has a drain and spring loaded bypass that the Alpine doesn't have.

The Mk2 supplemental wrench only fits the fittings at the oil cooler. The other hose fittings are all 3/4" AF (SAE)

I have a crash damaged Mk2 oil cooler (it doesn't leak). I wanted to take it apart to either repair or replace the cross tubes. I had thought about using Alpine cross tubes as I have several. That's when I discovered the difference in tube diameter. I ended up just standing on the oil cooler which straightened it out... Now all I have to do is pull all the cooling wires out again to make it pretty... as it's a spare, I'm in no hurry.
I believe I said basic design. Some modifications required for Tiger use.
 

Austin Healer

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I believe I said basic design. Some modifications required for Tiger use.
as you probably know, I make hoses for the remote oil filter set up for the all Tigers. I did specially make a set of hoses for someone in Florida to run an Alpine cooler with a Tiger. New fittings for the Alpine hoses are made of unobtainium and the hoses are different internal diameters (Alpines have larger fittings and hoses) I was able to recycle some original Alpine fittings and cobbled up a set of lines. I wouldn't want to do it again.

So, a little more than "some" modification required...
 

o2bdriving

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1 5/16 fits the closest, but it is likely a BSF/Whitworth size as all oil and fuel line fittings on English cars are BSB (British standard brass) thread. these use BSF/Whitworth wrenches that are based on the fitting diameter and not the size of the head. The special bolts for the oil filter adapters are 13/16 Whitworth!

There are NO metric fasteners on any English car before 1973.

You know why the French invented metric? It makes it sound so much longer than 6 inches......
I'm using the 1 5/16 on the oil filter but that seems too small for the fitting at the block. Do you know the size of that block fitting? The parts list shows two different part# but not the size. Thank you.
 

Austin Healer

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I'm using the 1 5/16 on the oil filter but that seems too small for the fitting at the block. Do you know the size of that block fitting? The parts list shows two different part# but not the size. Thank you.
the correct size is 13/16WW I bought a socket off of ebay some time ago... remember Whitworth sizes are the diameter of the thread, not the size of the head across the flats...
 

o2bdriving

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the correct size is 13/16WW I bought a socket off of ebay some time ago... remember Whitworth sizes are the diameter of the thread, not the size of the head across the flats...
Sean, thank you. Using a 3/4 crowfoot flare-nut socket to get around the header was able to loosen the fitting on the block adapter however it is ~1/8" too tight (between inner fender and engine block adapter) to remove the hose and tackle the adapter. I am considering a couple of options for removing the hose;
  1. Removing the steering bone to make room to wiggle it free. (it's so close, I can see the flare)
  2. Separate the hose at the fitting. Looks like it may be your repo hose.
  3. Back out the block adapter to see if somehow that frees it all up
Any ideas are welcome. I'll get it done but would appreciate the wisdom of those who went before to make it easier.

PXL_20241217_134045284.jpg
 
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Austin Healer

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Sean, thank you. Using a 5/8 crowfoot socket to get around the header was able to loosen the fitting on the block adapter however it is ~1/8" too tight (between inner fender and engine block adapter) to remove the hose and tackle the adapter. I am considering a couple of options for removing the hose;
  1. Removing the steering bone to make room to wiggle it free. (it's so close, I can see the flare)
  2. Separate the hose at the fitting. Looks like it may be your repo hose.
  3. Back out the block adapter to see if somehow that frees it all up
Any ideas are welcome. I'll get it done but would appreciate the wisdom of those who went before to make it easier.
I am assuming that you have already disconnected the hose from the oil cooler?? this will make it a lot easier to manipulate the hose I'd try the steering dog bone first, if that doesn't work you'll have to disconnect the exhaust from the header flange... Loosen the header to cylinder head bolts... If that doesn't give you enough room you might have to bash the header.

I've fit my hoses to cars with headers, both Mk1/Mk1a and Mk2 and while difficult, I've not encountered the problems you are having.

My hoses all use 3/4" AF (across the flats) fittings and not 5/8" so I have no idea where yours came from

I have found from past experience that it is a lot easier to deal with the hoses with the radiator out as well...
 

o2bdriving

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I am assuming that you have already disconnected the hose from the oil cooler?? this will make it a lot easier to manipulate the hose I'd try the steering dog bone first, if that doesn't work you'll have to disconnect the exhaust from the header flange... Loosen the header to cylinder head bolts... If that doesn't give you enough room you might have to bash the header.

I've fit my hoses to cars with headers, both Mk1/Mk1a and Mk2 and while difficult, I've not encountered the problems you are having.

My hoses all use 3/4" AF (across the flats) fittings and not 5/8" so I have no idea where yours came from

I have found from past experience that it is a lot easier to deal with the hoses with the radiator out as well...
you're correct, 3/4 across the flats. cold here so the hoses are a bit stiff. thank you for the tips.
 

Austin Healer

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you're correct, 3/4 across the flats. cold here so the hoses are a bit stiff. thank you for the tips.
The retaining bolts are the same size for the upper and lower adapters... if they are different, you likely have an aftermarket lower adapter. the upper adapter is aluminum and the lower is cast iron. If they are my hoses, they have a single inner wire wrap, so will be stiff regardless of temp! cold here too... snowing for the last 24 hours
 

o2bdriving

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The retaining bolts are the same size for the upper and lower adapters... if they are different, you likely have an aftermarket lower adapter. the upper adapter is aluminum and the lower is cast iron. If they are my hoses, they have a single inner wire wrap, so will be stiff regardless of temp! cold here too... snowing for the last 24 hours
Got it out after spinning the steering wheel a bit. The steering knuckle was in the way just enough to make for a tight fit. Is this your repro hose?

PXL_20241217_155537436.jpg
 
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