I’m looking for guidance from the Lotus community regarding the heater valve and am starting this new post as I could not add to the below which was previously closed. I have an early Series 1 Elan (October 1963). I believe I have a faulty heater valve and would like to replace it. I attempted to remove the existing valve however there wasn’t sufficient clearance as it made contact with the fiberglass body. I do have some clearance, between the bottom of the heater valve and the fiberglass body. I have not yet checked my engine mounts, to determine whether they have failed, however wondered whether a removal of a heater valve should be simple and accomplished with nothing more than a wrench to unfasten it and back it out by hand. Surely that would be the servicing procedure, right? Or would the engine need to be raised to be able to remove the heater valve? Thank you in advance for your guidance.
You normally need to undo the exhaust engine mount and raise the engine a little to unscrew the heater valve. this can often be done by just raising that side of the engine with a jack without even disconnecting the mount
The outer part of the valve can be removed by drilling out a rivet which enables removal in most cases unless the engine mount has collapsed but you still have to install the new one and I don’t like dismantling a new one
The replacement is normally not that straightforward!
I have on a couple of occasions managed to remove it easily, but it normally requires the LH engine mount to be slackened or removed, in order for the engine to be jacked up to provide necessary clearance to rotate the cable bracket surrounding the screwed nipple.
However, whilst rebuilding my Sprint the brand new engine mounts that I had installed two years previous, had failed even before the engine had been started for the first time!
The rubber vulcanising to the metalwork had come apart - noticed when the carbs started to touch the fibreglass bulkhead.
Rubber ain’t what it used to be !
The removal of carbon black constituents from rubber, due to carcinogenic issues has started to manifest itself - so check yours aren’t failing in any way, maybe adding to your pain!
During production Lotus made many changes to the body moulds. It’s a mystery to me why they didn’t change the profile of the fibreglass in that area to make heater valve removal easier. They must have had plenty of feedback from service centres etc. saying that it was a right PITA.
It is not difficult to fit the water valve in the forward position where it is clear of the body.
I did that some 10 years ago. The heater pipe has to have a slight curve on it to pass over the Temperature gauge bulb assembly and needs to be a bit longer to reach the new position. Fortunately mine had enough slack for this.
I am familiar with BSP pipe fittings having used them for cooling high power electronic equipment throughout my working life and had no trouble at all.
I got rid of the horrible valve years ago and fitted an in-line ball-valve in the passenger footwell. I can reach over and move the lever from the driver’s seat (preferably when not moving!).
