Elan +2 TwinCam Using Water

[yosini]

Hi,

Recently returned to Twink ownership with a Plus2, and have noticed that it is using a lot of water - recent trip to Le Mans it would need topping up with a litre every hundred miles or so. It's also using a reasonable amount of oil- I know this isn't too out of the ordinary, and it leaves a few drips wherever it sits, but the water usage is a bit of a worry.

If full of oil and water the temperature gauge sits perfectly in the middle, even in traffic. I'm not noticing any lack of power, and there are no gloopy nastinesses in the oil filler cap. Any ideas where this water could be going - hopefully not down the cylinders, but I can't see any signs of drips or leaks. If it is big trouble then what symptoms other than the above should I look/check for?

Cheers

Joe

[UpTheIron]

I had similar water (but not oil) consumption issues on a Chimaera once, and that turned out to be head gasket failure - only a tiny leak was enough. Car was fine for short journeys but longer journeys would result in losing litres of water.

Main symptom was the cooling system getting pressurised, resulting in repeated failures/leaks - water pump gasket blowing, radiator blowing etc.

[Lotus 50]

Have you checked the water pump? (i.e. that it's not leaking)

[anonymous-user]

When I had my sprint in 1974, I was concerned at oil usage, 400 miles to a pint, contacted Lotus and they told me not to wory at anything over 250 miles to a pint. I've just bought a twin cam for the first time since 1985 (Big valve Europe then) and not had it running yet, but remember they are not sealed systems like modern engines, my Caterhan 1700 super print, uses water all the time, boils off throught the overflow, needs watching and topping up. If you think its excessive I'd check the rad cap first before looking at head gaskets and big expense.

[kev b]

I agree with Berw, maybe you could try attaching a catch bottle to the rad overflow to see if that is the source of the loss.

Any decent garage can pressure test your cap and system and do a "sniff" test for head gasket failure in less than an hour.

Check for a leak from the water pump spindle as that is the weak spot on a TCam especially if the belt is a bit tight.

[Lotus 50]

The level of leakage does sound a bit odd to me, a litre every 100 miles or so seems excessive. If there isn't a pipe leading from the top of the radiator by the cap to an expansion/catch bottle then that might explain it, especially if you're getting an air lock in the system which expands when the engine is hot and would push water out. You will get some water coming out of the radiator cap into the expansion bottle under pressure but most of this this should get sucked back into the system when it cools down (the pipe running into the bottle needs to be long enough to reach to the bottom of it). The bottle will usually have some coolant in it even when cold but it shouldn't be overflowing, which it would be if you're losing this level of water. It is quite difficult to get rid of all of the air in the cooling system on a standard +2, squeezing the top hose etc and even jacking the front of the car up when topping up the system may help...

If there is a problem with the water pump there is likely to be evidence of water leaking at the front of the engine/on the sub-frame cross member. You are also likely to find play in the pulley bearings. Relatively easy to check but not so easy to sort out. The other thing to check is whether or not the radiator has a leak (antifreeze stains) - if they are on the front of the rad these can be difficult to see given where the radiator sits and, I guess, you may not get visible drips under the car as the coolant may well evaporate rather than drip. As an aside, if the car is loosing coolant it's important to keep the anti-freeze levels up as it inhibits corrosion in the cylinder head and (I seem to recall) also helps to lubricate the pump.

Edited by Lotus 50 on Monday 14th July 13:13