I'm going to just call it a 98' xjr so I don't confuse people lol.

Changing the radiator has turned Into a huge pain,
Both gearbox oil cooler lines were seized solid in the radiator, one came out taking the thread out the radiator, the other didn't budge at all so got cut off.

I keep reading changing them out is quite a big job but can't find any info on what it actually entails.

Could I just chop some good unions off a scrap car and join them to the pipes (minus the ends) on mine.

I'll keep plodding along keeping this thing on the road but God it's testing my patience.

 

Why not get new threaded ends and a flare tool and re-make them? Or, like I did once with a BMW 735i, buy the manual transmission radiator without the trans cooler in the end tank, and buy a cheap liquid to air heat exchanger and mount it in front of the radiator and put some hoses on the trans lines.

 

I had to cut the pipe to get the radiator out, so I can't really do much with it other than join it to another cut peice with the fitting on.

What sort of pressures does the hose see?
Double clamped with a load of hydraulic sealer be enough?

 

There is no info on what the pressure is in the cooler lines. On the 722.6, this circuit is actually part of the transmission lubrication system so there must be some considerable pressure in it, probably in the order of 50 - 100 psi. So, with a safety factor, I would consider 200 psi.

Putting a rubber hose on a smooth aluminium pipe will not hold, neither will any sealer. The only way I would try is by cutting the front rubber section of the existing (cut-off) line somewhere convenient for installation of a barbed extension piece. Then, you should get a used line and make a cut at its front rubber section at about the same location as where you cut your existing line so that, when connected, you get about the same length to the cooler port. Make sure that the cut at the rubber hose of the "new" section leaves sufficient length of the rubber hose to accept the barbed extension piece. You will need to find a suitable brass or aluminium barbed extension piece that goes rather tight into the rubber hoses and double-clamp it to make the joint.

 

I was thinking instead of hose clamps,
I could use a straight compression fitting instead?
I think I saw they are good for up to around 400psi

 

Yes, that would be very good. The diameter of the aluminium pipe is probably metric. I see that this website (https://www.airlines-pneumatics.co.u...-equal/S060143), in addition to imperial, also sell metric ones but up to 12 mm (you can search for a bigger one if needed).

 

Measure the ID of the pipe and find a hard-line-to-AN fitting that fits it, then add an external oil cooler.

 

I'd prefer to just use the stock one in the radiator,

Theres already the main radiator,AC radiator, supercharger radiator,engine oil cooler and power steering cooler .. don't really want to add another cooler.

 

I hear ya. I was just trying to think of "easier" alternatives.

 

All done and working again now,
The pipes are 1/2" not 12mm so couldn't get a compression fitting, went with the barb fitting in the rubber hose section, worked perfectly