Heater motor

[gerrym]

Mike, I used closed cell foam rubber strip (self adhesive) from Vehicle Wiring Products. part no FRS tel 0115 9305454 . It comes in 3mm thickness, cut to required width. For the flap that directs air up to the demister, I used thermoplastic garage door seal: it needs to be quite stiff. For the door seal, I'll have a hunt around and see if I had any left over. (might have chucked it)

Regards

Gerry

[mikealdren]

Gordon/Gerry,
Thanks guys.

Gerry, I was looking to replace the foam with a large sheet as the oringinal fitting but I like your solution of using a strip - does it look as though it will last well? I suspect that domestic door weatherstrip foam may be ok too.

Mike

[JJDraper]

I replaced my +2 heater unit a few years back and it is a pain to take out & put back.... My heater motor had packed up and this made winter driving very difficult. I picked up a second unit which I 'reconditioned' by replacing the foam sheeting with some from computer motherboard packaging! I have no idea what the long term performance of this will be, but it has been OK for the last 4 years.. The sealing edge strips looked OK so I left them alone. I also sealed up all joints in the box with silicone to make it air tight - every little helps. The motor was checked by running it for an hour or so connected to a battery before fitting to the car.. Easy so far.

Fitting to the car required dropping the steering column a few inches away from the dash, removing dash, disconnecting heater hoses at the engine, unbolting the heater unit and withdrawing the whole assembly from the car, dissconnecting all the other little bits and peices on the way. This work was carried out in conjunction with a head gasket change, and this helps a great deal.

Take lots of digital pictures and lable all wires... You have got a digital camera haven't you?!

Inspect the area where the hoses go through the bulkhead carefully and check the foam gaskets that close the gaps between heater unit and bulkhead. Mine were just about OK (does anyone offer rfeplacements?). To get the unit back in, I decided to replace the heater hoses with over long sections of hose (cheap enough), tightened onto the heater pipes - very tight! I slightly enlarged the hole in the bulkhead to allow the hose & clips to pass through while connected to the heater. Be very careful when enlarging the hole - to big and the foam gasket will not seal properly, too small and the hoses and clips will not go through. Pass the over long hoses through the hole followed by the heater and bolt the unit in place.

From the engine bay, grasp the heater hoses and route them correctly, then cut to the correct length. My original heater hoses had a loose stainless steel coil spring inside them for their whole length, presumably to prevent kinks and crushing - seems to work very well.

As the manual says reassemble everything in the reverse order - easy! It took nearly two weeks to get everything working on the dash.... Heater has worked OK ever since. One thing I have noted is that the heater motor seems to be the biggest single electrical load on the system, including the lights on full. My voltmeter holds steady at 12.5 volts with all lights on, but with the heater alone, it drops to 11.5 and lower.

With regard to the space for a radio. check this site out, and the brilliant mod to the heater box. Unfortunately I saw this after I fitted the new heater.... Is the owner of this website still active??

http://www.lotuselan.info/october.htm

If/when I take the plunge and do the right thing and carry out a full refurb of the car, the heater is an area for close attention for modding, especially the fan arrangement & space for a radio. Anyone with experience of this? Do Zetec conversions still use this crude device?!

Jeremy

[mikealdren]

Jeremy,
Thanks for the post. I made a similar mod to the heater of my +2 when I bought in 1980 but I always suspected that it reduced the airflow through the box. I also didn't quite cut the box back far enough so the radio still protruded from the dash by a small amount.

The Zetec conversion doesn't actually change the heater although it runs hotter so it should give out slightly more heat.

As you say, the plus 2 heater isn't great by modern standards, so I am keen to do all I can to improve it.

Mike

[mikealdren]

After a long gap (don't ask) I'm back on my Zetec build.

Has anyone used a more modern (better) heater motor in the years since this thread was active?

thanks
Mike

[USA64]

https://www.thhs.co.uk/
12v HEATER MOTOR (SMITHS TYPE)

M1210

It took a bit of hunting. This is off a saved email receipt. It's the original type, perfect fit, if by "modern" brand new will suffice.

[Gordon Sauer]

I’ve had my +2 since 89 so I guess no surprise that I wrote some things here in 2007 and I still have the car now. And it still has the Vintage Air unit in it that fully replaced the heater box and all, along with cutting back the Plenum to give it room. Car came with Lotus distributor installed AC unit so used that bracketry and a bean cartridge water pump and all is well these many years later. And then I have a Pye Clearway Radio as original which fits without protruding along with great heat and AC. Just did this to my S2 Esprit as well but these are both complete strip jobs. Improvement over the Wheezy blowing of the original units is remarkable and worth it for an enclosed car in a very hot climate. Gordon Sauer

[The Veg]

I used something more modern that was suggested to me by 1owner69. It's a motor for the system in some kind of truck if I remember correctly.

Pros: housing shape and size and shaft-diameter are all a good fit, is pre-wired for two speeds so the external resistor on the side of the heater box is no longer needed.

Cons: housing does not have mounting ears like the Smiths motor so you'll have to fab-up something, keeping in mind how big a job it is to go back in there if what you make ever fails.

[baileyman]

My Elan heater box was pretty rotten, so I glassed it back together and got a small radiator fan that almost fit between the radiator elements. A little trimming of the housing and fan diameter (this using a fine wood rasp while the blade spun) and it slipped in. There was no good way to put an original style fan on the rotten box. The modern fan blows really great, but the car leaks so much air and water into the cabin that I wonder if it matters much. It's not concourse, but also totally invisible. John