Water leak - Possibly ?

[Rob P]

Guys,
Looking for some guidance after taking the Lotus out for a spirited dash at the weekend. No issues whilst driving through the Yorkshire dales and over the border back into Lancashire. Parked the car up at tea time, then went out later that evening and put the hood up and the cover and didn't notice anything strange.

However the following morning I came out to the car to find a small amount of fluid in the clacks in the pressed concrete driveway, the liquid was a rusty colour but on closer inspection the actual colour appears to be pink so I'm thinking it is coolant. Is this correct ?

Today I have been under the car looking for tell tale signs of any leaks and nothing could be found. Took the car out for a little drive after checking the Expansion tank was still full, looked slightly down but certainly not empty. after the drive I went under the car again and still nothing. I've had a look around the Vital Fluids posts and can't see anything of this nature so wondered what people think this might be, is there a release for pressure on the expansion tank that might have kicked in? at a loss guys as there is nothing obvious to be seen

[GeoffSmith]

If it is pink (and oily) then I'd suspect power steering Rob. Throw some water on it to check whether it is oil or water based.

[Rob P]

If it is pink (and oily) then I'd suspect power steering Rob. Throw some water on it to check whether it is oil or water based.

Thanks Geoff I did wonder about it being power steering but there appears to be no change to the power steering capability on the car and checking the level seems to show no loss of fluid, had the front wheels off this afternoon and cleaning off all of the Underside to see if I could see anything and currently can't see a thing

Any specific areas that would warrant checking as a starter for ten?

[HJ2]

You could check the color of the liquid in the coolant reservoir!
Open it up (not whist hot ) and check the color of the liquid inside. If it is the same as on the driveway, then it could me your waterpump. The can leak sometimes only in the transcient from hot to cold, when almost cold. After total cooling down the dripping stops again, leaving you wondering where it came from.

[Rambo]

But should the antifreeze in the Elan not be Ethyleane Glycol based ie blue rather than the OAT (organic acid technology) based coolant ie pink ??

If you have blue coolant then its likely to be PAS fluid as Geoff has suggested. If you have pink coolant then it could be PAS and/or coolant leakage

[Rob P]

Checked the coolant and it is indeed pink took the car out for a little trip tonight and Power Steering still working as it always has so looks like it is a coolant leak of some sort albeit quite small

I have parked the car with a white sheet underneath the engine this evening so any minor drips can be found in the correct location in the morning and hopefully highlight the offending part.

Thanks for the feedback guys, I'm sure I'll get to the bottom of it tomorrow

[HJ2]

Then my guess is that the use of pink coolant ate away the brass of your heater valve and it is leaking now.
A lot cheaper than a waterpump, and do change the coolant! (Green is the colour of my choice).

[GeoffSmith]

do change the coolant!

Sooner rather than later.

[Rob P]

Then my guess is that the use of pink coolant ate away the brass of your heater valve and it is leaking now.
A lot cheaper than a waterpump, and do change the coolant! (Green is the colour of my choice).

Thanks HJ2, sounds very feasible and I must admit I was reading about the different coolants on another thread the other day and thought I would do a check at some point. I assume the heater valve is tucked away somewhere difficult to access (as most things are on this car lol)
I'll have a look at the manuals to determine where this is, assuming this is the offending part are these readily available as spares from anywhere particular before I go searching the Web?

Green Coolant, is that any specific make that you recommend? If I'm going to make the change I might as well go down a route already travelled

BTW after giving the car a good old clean underneath and taking her out yesterday in the sunshine I placed a sheet under her and this morning no coolant at all. I drove yesterday without the heater on because of the sunshine so I wonder if it only happens to leak when the heater has been in use?

[maz_r]

Useful info here in the Wiki

[Rob P]

Useful info here in the Wiki

Perfect, Thanks for the info, once the car is back on the drive (Note to self, never put son on insurance if I want to see lotus again) I'll give it another look and check this part out

[epipete]

Iirc, with the heat turned off the Coolent doesn't circulate the heater matrix part of the circuit thus there would be no leak (if the valve is sound). On the other hand most of the heater circuit is the cabin side of the bulkhead so any leaks there will be in the footwell.

You can feel both of the pipes from the bulkhead forewards to their respective links to the main system and see if there is any wetness there.

[HJ2]

The coolant is pressurized either way, so a leaky valve will leak under the bonnet i'm afraid.

[Rambo]

Rob - as previosly mentioned you need the Ethylene Glycol coolant (tends to b e blue over here) not the organic acid technology (OAT) pink stuff

The pink stuff rots your bits due to the use of different metals

PS Bloody EC have a lot to answer for

[Rob P]

The coolant is pressurized either way, so a leaky valve will leak under the bonnet i'm afraid.

I was hoping that would be the case as I haven't had any dampness in the foot wells for some time now
If my lad ever brings it back home today I'll have a look at the Valve specifically, probably more likely to be a job for tomorrow. Then if it is the point of failure then purchase replacement, drain system and replace with something Blue

Thanks for all the guidance guys

[Rambo]

Make sure you use a coolant flush and thoroughly clean the closed circuit. OAT and EG don't mix well

You will have better compatibility with the metal parts using EG (blue)

[HJ2]

More good advice!

[Rob P]

Well I am now totally at a loss as to what the liquid was/is, after the car was out all day yesterday with my lad there have been no further leakages, the coolant level hasn't dropped and the power Steering level is the same as it ever has been
I've been under the car with a fine tooth comb and can't find any leaks (well except a couple of Oily ones which I already knew about.)
Checked the Heater Valve which looks rather old and tired but no leaks, all the hoses look good (Silicon hoses all round in Blue, I would prefer Black but it was what it came with)
Power Steering connections are all good, no leaks from the pump either and the usual whoosh noise when steering wheel is turned when stationary.

I will as a matter of course be changing the coolant as you guys have advised and will look at best flushing methods online to ensure a clean system before topping up with EG. Just one question, has anyone used the Evans Coolant stuff that Ed China was touting about last year??

Thanks again for all the info, been really useful to find my way around some bits of the car I haven't had to touch as yet

[HJ2]

So that returns us to the water pump by the looks of it....
I used the Evans Stuff in Peter's car and it runs fine!

[Rob P]

So that returns us to the water pump by the looks of it....
I used the Evans Stuff in Peter's car and it runs fine!

Thanks HJ2, funny enough the water pump was swapped out just after I got the car, so maybe just two years ago now when the Cam belt was done.
I did run it on the drive this afternoon and let the fans kick in, well one fan kicked in so might have a dodgy fan as well but the one fan quickly cooled the car sufficiently quickly to not worry me and still no leaks, I have a run out this weekend for St Georges day so will see how she behaves on that and then it's coolant change time

Might go with the Evans stuff if I can be convinced the leak isn't going to reappear, I hear it's expensive stuff