Heater upgrade

[wearthefoxhat]

Hi again. My 1963 Traveller has the round heater matrix. Is it possible / difficult to upgrade this to the square type matrix? The front panel has the hole for the fresh air ducting but no hole in the bulkhead. Would the heater tap on the block have to be upgraded to suit? I've done a search on here and there is a reference to the "workshop manual" covering this conversion. Can someone point me in the direction of this manual via a link?
Thanks in advance as usual.

[ampwhu]

look at an A35 manual. it was fitted as standard, but an optional extra.

[IslipMinor]

There is a section in the BMC Workshop Manual that covers fitting the later 'fresh air' heater, complete with the necessary measurements -Section 'SS'. You will need to make a hole in the bulkhead, large enough to take the heat trunking AND the large 'O' ring that protects it through the bulkhead. Extract below:

Heater Upgrade Fixing Pt 1.jpg (167.26 KiB) Viewed 773 times

Heater Upgrade Fixing Pt 2.jpg (857.46 KiB) Viewed 773 times

Heater Upgrade Fixing Pt 3.jpg (1.39 MiB) Viewed 773 times

Heater Upgrade Fixing Pt 4.jpg (105.51 KiB) Viewed 773 times

I did this many years ago, and then a few years ago had to replace the matrix, so took the opportunity to fit a complete unit from a Mini that has more heat output. Adapting the front of the heater from a Mini to a Minor took a little while, and I also fitted 5/8" bore hoses (as Mini) to get the most water flow through the new unit. The original brass heater tap is fine (though not as convenient as the later 'push/pull' control), and on ours the return hose still goes directly into the bottom of the radiator, where the original 'round' heater return did. No reason not to use the later return into the bottom hose if it already fitted.

With either an 82°C or 88°C thermostat it seems to give a good output, but still a bit limited on a really cold winter's day! Fortunately, we don't use the Minor regularly in the winter.

[wearthefoxhat]

Thanks for the quick replies. I have now printed off the details posted by islipminor and will digest.
Thanks again