Mystery leak

[MelBee42]

Hi all.
I have a had a slow coolant leak for a few weeks now. I took it to the garage where they checked everything (or at least they say they did) and finally said there was a bit of leakage around the nipples (insert your own joke here) and they changed the washers. They did however say that they weren't really sure what the problem was and had no idea if what they'd done would fix it (or not).

Seemed to be OK for a couple of weeks, kept checking the coolant level, topped up once a while ago but after that the level was low but steady. Evetnaully I kind of thought it was fixed and failed to check the level for a few days (my bad). This was an error. Engine overheated this morning en route to the motorway. (Can I just say, some people are really unncessarily rude and unhelpful. There was steam coming out of the flipping engine bay, I was indicating to move into the left lane so that I pull off the road, did anyone want to let me through?! Did they heck as like.)

Topped up with all the coolant I had (took it to the 'full' line) and got to work fine. (50 mile trip) However after checking on arrival, the coolant is empty again. I don't have any here either, which means a lovely 3 hour series of train journeys home.

Anyway, complaining aside (sorry, you can tell I am feeling very grumpy today!), I will be taking the car back to the garage tomorrow. However as they didn't help last time (although they did try, and they didn't charge me) I don't really have much faith that they will fix it this time either. So my question is, what should I ask them to check?

Some background facts:
- Car is pre-facelift but facelift engine fitted 6,000 miles ago (October)
- No obvious leaks (no liquid in the drive, anyway)

Oh, and on another topic, the power steering problem I had has mysteriously vanished for the last week. Not sure what's going on with my car to be honest!  s:( s:(

[Anonymous]

front plastic's off and check the rad. sounds like a small leak on the rad. if it is leaking then you will notice a little water on the bottom plastic under the rad, also on another note if the water taste is bitter it is coolent as anti freeze has a bitter taste. when it does run low the air in the system will be of such a level when you filled it up it would of disapeared as the air was removed from the system.

[MelBee42]

Thanks. I asked them to check the radiator last time. I can but ask again...! And will see if I can have a look myself as well.

[Wabbitkilla]

You say you were getting steam from the engine bay?

First thing is take the frunk plastics off and take a look at the Rad, minor leaks can show up by the pink staining and build up of dried out coolant, usually quite obvious once you've spotted them. Recent memory tells me someone had the front-back hard pipes leaking and had to replace one, so time to have a look at them.

From the sounds of things it sounds like it's disappeared relatively quicker this time so any decent garage should be able to find that obvious a leak.

[Peter Wright]

If you cant find a leak you might have to look at possible head gasket failure

[MelBee42]

You say you were getting steam from the engine bay?

First thing is take the frunk plastics off and take a look at the Rad, minor leaks can show up by the pink staining and build up of dried out coolant, usually quite obvious once you've spotted them. Recent memory tells me someone had the front-back hard pipes leaking and had to replace one, so time to have a look at them.

From the sounds of things it sounds like it's disappeared relatively quicker this time so any decent garage should be able to find that obvious a leak.

Thanks. It was disappearing at this rate previously, and the garage could only find the leaky-nipple issue (and after they replaced the washers it did pretty much slow down/stop, though appears obviously to be leaking as much now as it was before...!).
I did ask them to check around the rad last time but as the person who gave me back the keys wasn't the person who checked the car, I'm not really sure what they did.

Yup, steam from the engine bay. Coming from the top right hand side.

Head gasket... yes possibly, and it's what killed my MGF.  s:( s:(  Almost exactly this time last year in fact! Also due to inconsiderate idiots not letting me pull over, I had to keep it running way longer than I would have wanted - so could have done further damage.  s:( s:(
Hopefully I actually make it to the garage this time!

[Dyn-Evo]

Yeh...H/G is a possibility...!  s:? :? s:?  

How was your expansion tank?

Empty, or overflowed..?
Was there evidence of coolant being ejected from your coolant reservoir overflow pipe..?

If so, then its going to be H/G related: the coolant cap is rated at around 12psi......shoving extremely hot gases at 150psi+ into a sealed, pressurised coolant system is going to stress something.....

As the expansion tank overflow pipe should be the weakest link / path of least resistance for the coolant, it should have ejected loads of coolant....?

Also, do you have white smoke from your exhaust on throttle...?
Depending on the severity of the H/G failure, its likely that coolant is being forced INTO the cylinder(s) on the intake stroke, by the (over)pressurised coolant system..?
Have you got any symptoms of misfire..?

Its possible that the H/G only fails when the engine is hot: that means you'll only notice the problem on long(ish) journeys...?

Also, check REALLY carefully for leaks at hose joints (anywhere there is a clip,basically).
I spent ages tracking down a coolant loss problem on mine, only to find a hose join leaking, but only when the engine was hot, and up to full temp/pressure!

Pay particular attention to the heater pipe run: thats where mine was.....!  s:wink: :wink: s:wink:  

Let us know..?

[Wabbitkilla]

Head gasket, Water pump, or pipe.

Take it to a decent garage.

[MelBee42]

The expansion tank was empty.
No evidence of liquid coming out the overflow that I could see. Just a *lot* of steam coming from around where the dipstick is.
I have however noticed dry white residue around the engine bay in the last few weeks. Don't know if that could potentially be dried coolant? It's definitely not pink.
White smoke from the exhaust - yes, but only when the engine's cold.
Misfire - no, well certainly not usually anyway, though it sounded pretty rough when I started it up again after filling up with coolant on the hard shoulder.
More background info - engine overheated after 15-20 mins (half of which was spent stuck in traffic).
Thanks all - I have copy/pasted your suggestions into one handy document which I will give to the garage.
My only worry is making it there OK and without doing any further damage to the engine, as I'm 50 miles from home and really need to take it somewhere local to where I live.
Just top up with coolant and hope for the best...?!! That plan worked out pretty badly on the MGF last year!

[aaronjb]

Steam from the dipstick area would point to waterpump or the hose from the thermostat housing (just below the alternator on the back of the block) as Nic suggests.

Since this garage has had one shot at finding the leak already, ask them if they pressure tested the system - if they didn't, I'd suggest finding a better garage.

[MelBee42]

Steam from the dipstick area would point to waterpump or the hose from the thermostat housing (just below the alternator on the back of the block) as Nic suggests.

Since this garage has had one shot at finding the leak already, ask them if they pressure tested the system - if they didn't, I'd suggest finding a better garage.

Thanks.
I specifically asked them to pressure test the system... they said they did. They've always been good to me previously (and at least they didn't charge me!).

[uktotty]

I specifically asked them to pressure test the system... they said they did. They've always been good to me previously (and at least they didn't charge me!).

Got your moneys worth then!

Not heard of anyone blowing a head gasket, which is good

[MelBee42]

Not heard of anyoen bowing a head gasket, which is good

Well if it's going to happen to anyone, it'd be me, the way my luck is going!  s:( s:(

[2 of the left]

I have had same problem for a few weeks now After advice from the forum I checked the rad after removing the "frunk" plastics and found pink deposits so to keep me going until I can afford to get done all that is needed (New rad and pre-cat removal) I threw in Rad Weld which has held it until to day Have checked all levels daily - On Saturday found reservoir nigh on empty - so ran the car for 5mins whilst cold and watched the coolant level rise but it was way below minimum - Did the work commute today and before returning home checked levels again - The reservoir tank empty again! - So filled to minimum level with fresh coolant -Will have to check tomorrow in daylight to see what levels are reading. NOW before anyone goes off on one regarding using Rad Weld it's a "stop-gap" solution and as I'm to fork out for new rad shortly the system will be flushed. Had same problem with my Mk2 but ended up with steam in engine bay and warping the engine so that trying to fit a head gasket was more or less impossible - hence p/x ing for the Mk3

[2 of the left]

Further to my last - The white residue you have spotted in the bay is a direct result of having steam under pressure in that area!

[Anonymous]

Rad weld does work at filling in holes. It is also good at blocking small water holes in the water pump and engine. Its try your luck stuff.

[loadswine]

its a get you home solution really. once you get home and get the right component fitted, the system should have a good flush.

[MelBee42]

Thanks all. Took the train back on Monday night (and back in this morning - this time with more coolant!) - topped up the coolant, and managed to get back to the garage safely. Asked them to look at a few things but they were a bit dismissive to be honest! Will see what they say tomorrow...

[StuC]

It least you didn't have any disasters on the way home, luck was with you then!  :-) :-) :-)

[Anonymous]

If youre 50 miles from Nottingham, anywhere near Matt at Water Orton?

[MelBee42]

The car is at the garage that's walking distance from my house at the moment! Thanks though  s:) s:)

[MelBee42]

It was the head gasket.  s:( s:(  Just waiting now to find out how massive the bill will be...  s:( s:(

[nathanMR2]

Are they sure as we don't see many of these go?

You really dont have much luck!  s:( s:(

[MelBee42]

They were quite sure, they said they did a chemical test (I think - I possibly stopped listening after they said head gasket!) to confirm. Total bill £740. The exact same thing happened to me last year with the MGF - almost a year ago to the day in fact!  s:( s:(

[Peter Wright]

It was the head gasket.  s:( s:(  Just waiting now to find out how massive the bill will be...  s:( s:(

Or cracked cylinder head   s:( s:(