Lotus Elan and Lotus Elan Plus 2 Forums

While on my annual 1200 mile tour, the diaphragm in the heater water control valve ruptured. Immeditae loss of coolant, thank god for anti-freeze, which I smelled as soon as the diaphragm let go.

Having just replaced a similar valve on another lump I am restoring, the valve, mounted to the car is of the newer style. with a spacer behind the diaphragm, next to the outer stamped housing, unlike the one I just replaced.

The question is: Is this another piece of asian junk rubber, that is now the only available replacement? Or is this tearing normal, and requires a "spare" to be carried for use in underway reapirs?

No damage done, because the coolant odor allowed immediate shut down and temporary repairs. Was carrying extra water, they don't call it Death Valley for nothing. No other problems and no additional loss of coolant getting back home.

Should I order another one????
Rob Walker
26-4889

I had one of those go on me a long time ago.

I seem to recall I made a temporary fix of some sort. Possibly with some rubber in the spares in the boot

Perhaps it might make more sense to carry a blanking plug for the head and a clamp to squeeze shut the top heater hose.

prezoom wrote:The question is: Is this another piece of asian junk rubber, that is now the only available replacement? Or is this tearing normal, and requires a "spare" to be carried for use in underway reapirs?

Should I order another one????
Rob Walker
26-4889

My control valve is the original 1969 vintage and I've had zero problems with it. I didn't even realise there was a diaphragm in there! Who knows whether modern replacements are substandard or whether you've just been unlucky but there does seem to be a trend towards rubber bits not lasting as long as they used to - gear lever gaiters, rotoflexes etc. Having just replaced my Stromberg diaphragms I'm now wondering how long they'll last?

Rob, I'm going to be a pedant and a total PITA and advise that Plus 2s don't have a heater water control valve. Ergo, this post should not be in the "Things in Common" section. There you go, got that off my chest.

Regards

gerry

Stuart, my new brake and clutch pedal rubbers lasted less than 2 years, now totally perished and useless. The one I took off were worn but not split after more than 30 years. We are being had!!

Thanks everyone. Wasn't sure if this was a new or continuing problem. Adding parts to the kit in the boot, to take care of this problem if it ever comes up again. I could whine about it being another Lotus problem, but just about every British car uses one variation or another of this valve.

gerry......well excuse me!

Rob Walker
26-4889

Rob, no excuse me!
Would the heater work with a just an on/off manual valve under the bonnet, no rubber to fail? Just too inconvenient?

Regards

gerrym wrote:Rob, no excuse me!
Would the heater work with a just an on/off manual valve under the bonnet, no rubber to fail? Just too inconvenient?

Regards

Yes, I suspect you could work out something of that sort. And who needs "partial heat" in an Elan anyway?

Hmm, if you can get a tapered brass fitting to screw into the head, you could probably make a better control valve from a standard domestic plumbing washing machine tap.

billwill wrote:Hmm, if you can get a tapered brass fitting to screw into the head, you could probably make a better control valve from a standard domestic plumbing washing machine tap.

This is one I was considering installing on my Plus 2 to replace the ell; as Gerry mentioned Plus 2 does not have a coolant valve and relies on flaps in the heater box to turn the heat off which does not work all that well on a hot day.

Not sure if the threads on this valve would be the same as the Lotus? This part is billed as for a 1098 or 1275 cc MG Midget. Back in the day my 998 cc Midget had a valve like this under the bonnet, but I do not recall if it was threaded in or used a mounting plate. Perhaps someone knows if the treads are the same or what the Lotus heater valve thread size is?

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... K:MEWAX:IT

stugilmour wrote:
Not sure if the threads on this valve would be the same as the Lotus?

I think it's a standard pipe thread.

I don't know if it's of any relevance to this thread but in my S4 Zetec conversion I used a Solenoid Heater valve from a modern car.
It has push on stubs for the hoses which are secured by Hose Clips (Jubilee's)
It's situated close up to the right of the heater above the Driver's leg & supported purely by the Hoses going in & out of it.
It's controlled by a switch on the Dashboard & is of course either fully on or off.
The Switch is positioned where the push / pull control for the original mechanical Valve would have been. No Holes remaining & no new Holes needed anywhere.

John

John,

Do you happen to recall the brand/part # for that solenoid valve? Is it half-inch? I tried hard a couple years ago to find such a part with no success.

-Will
45/9693

Yes the part I used was made by Bosch for a BMW, which is not really where you want to be searching for a Part that doesn't cost too much.
I've attached a Photo so that you can get an idea of the size.
The Stubs are for 20mm I/D Hoses but I had to get some Nylon stepped adapters to get down to the size to suit the Heater; they're available straight or 90?.
I also hacked off the 2 Pin Connector & soldered on flying leads which I then secured to the Valve Body with 2 Component Epoxy.
Hope that's been of some help?
Cheers
John

Sorry I'm having problems downloading the Photo.
The Body of the Valve is about 100mm long & the plastic Stubs come out of one end of it at 90?.
The Body Dia. is about 30mm

D.J.Pelly wrote:Yes the part I used was made by Bosch for a BMW, which is not really where you want to be searching for a Part that doesn't cost too much.
I've attached a Photo so that you can get an idea of the size.
The Stubs are for 20mm I/D Hoses but I had to get some Nylon stepped adapters to get down to the size to suit the Heater; they're available straight or 90?.
I also hacked off the 2 Pin Connector & soldered on flying leads which I then secured to the Valve Body with 2 Component Epoxy.
Hope that's been of some help?
Cheers
John

Sorry I'm having problems downloading the Photo.
The Body of the Valve is about 100mm long & the plastic Stubs come out of one end of it at 90?.
The Body Dia. is about 30mm

Aaaah! got it on there now

The tap you show above (not the later solenoid suggested) looks as if it needs multiple turns to operate it, so it would be a bonnet up manual operation.

The reason I suggested a washing machine tap is because these operate with just a 90 degree quarter turn and have a detachable plastic handle, so it should be quite easy to make a lever which can be operated by the original dashboard pull wire control.

Obtainable at most DIY stores.
http://www.diy.com/diy/jsp/bq/nav.jsp?i ... p&x=16&y=9

You would need a few more plumbing bits to connect it in, though all but the tapered thread should be quite standard.