My AK 427 Cobra adventure: Hot stuff

As a change from beating an infuriating piece of stainless steel one of the other pre-body fit tasks is to sort the heater.

This is a donor item from a polo Mk2/3 which AK kindly sourced for me as I wasn't having much luck.

It's a pain to get to and virtually impossible to fit if the body is on chassis with engine in.

So. First check it's a runner with a bit of testing with the ammeter and then checking the wires with a bit of 12volts. Good fun and it's definitely a runner with 3 speeds.

The IVA test requires a windscreen delisting device which doesn't require the use of a human hand smearing a small window. Hence the need for the fan. Plus passengers do like a bit of hot air on their feet in winter.

Labelled up I can now take it to pieces to do a thorough clean.

Expected issues that need addressing - matrix degradation due to age. £24 no postage from eBay in Germany sees a new one delivered in 3 days inc foam.

And the valve featured above has an oring which leaks as soon as other builders have connected up their pride and joys...

So that's coming out and a replacement sourced for a few pennies from B and Q is installed with a bit of red rubber grease.

One of the other key IVA criteria is not to have any engine compartment air feeing into the heater fan. So this needs blocking off (B&Q have a nice guttering down pipe adapter thing which with the offset outlet means once you trim off the outside ring it's perfect for fitting between the hot water pipes.

This then needs one more flange from car builder solutons to connect to the bulkhead to draw air in from the passenger footwell.

Which should be the angled black GRP on LHS of the above photo next to the stainless engine bay cladding that I've just fitted!

The motor end of the heater is also open. The opinions are split as to whether it actually draws much air across it or not. I was originally going to leave open but again for IVA belt and braces I've now made a closed end cover for this too using part of a sanitary ware fitting from homebase and a shaped with a Stanley knife.

Above ready to cover

A healthy dose of sealant applied

And the main input end cover sealed on. I'm going to be using a 68mm flexible wire reinforced hose from CBS to allow a good airflow, which will mate to this flange below on the bulkhead (also from CBS)

Cutting the aperture for the heater was fun. Really, it was. I had forgotten how grim fibreglass dust is until I started cutting with the dremel. In hindsight a more coarse cut and less speed approach will be used for the boot floor cutout for fuel filler etc. Having made myself look like a ghost with a bit if fettling of the heater box itself I got it located in what I'm hoping is the right place.