Water Leak => Really Looking Like Head Gasket Now

[revilla]

My engine (K-Series VVC) is leaking coolant from somewhere around the head/block. I know the immediate response would be HGF but I'm not convinced at the moment ...

 

After leaving the car parked up for a couple of days there is sometimes a drop of coolant under the starter motor solenoid. There is quite a lot of staining and deposit from coolant which has run down to this point and dried. There is some slight staining from coolant on the head/block joint and the side of the block, but difficult to tell straight away where it is actually coming from in the first instance.

 

There are absolutely no symptoms other than a bit of coolant leakage. The car starts first turn, runs sweetly, pulls like a train. Absolutely no sign of water in the oil or oil in the water (although I know they can commonly fail between the water jacket and the outside edge only). The coolant is crystal clear pink and I recently drained the oil which showed no signs of cloudiness, mayonnaise or similar. Oil and water filler caps are perfectly clean. No odd symptoms of pressurisation in the water or unexplained movements in the water level.

 

The engine temperature seems to be pegged at just over 80C after warming up whatever I do, gentle driving or pushing it, hot day or cold. In the time I've had it, it has never once indicated any hotter than this. The fan cuts in and out seems to keep the temperature very stable under all conditions. I always warm it up thoroughly before revving it.

 

It must be a very slow leak as in the year I've owned the car there has only been a very slight drop in coolant level, however there is quite a bit of pink/white coolant deposit around which suggests to me it has been leaking slowly for quite a while. Whilst there is a lot of coolant deposit under the starter, there isn't any staining on the floor below it, so I think the leak is so slow that the water is running down to the lowest point and the evaporating before it builds up enough to drip. Only once have I spotted a single drop on the floor. I first had it pointed out to me by Nick Potter when it went into his garage for something else. I must have done 1000 miles since then with no sign of it getting any worse. To be honest it gives the impression that it's probably been leaking very slightly for years.

 

It appears to leak when cold rather than when hot. There is no sign of steam or spraying of water when the engine is hot and running, just a very slight seepage when the car is left parked up in the garage.

 

Given the location of the staining I was thinking of cleaning everything up and checking a few of the other known failure points to see if I can see where it comes from. I know they can leak around the water rail (either from the gasket where it joins the head or from hairline cracks or faulty welded joints). I was also going to look carefully at the water pump gasket. Another known failure point is the inlet manifold gasket, but from what I've read it's a lot less common on the VVC (aluminium) manifold and the distribution of the leaked coolant is on the exhaust rather than inlet side of the engine, although I know it can run around the engine especially with it being tilted at an angle in the Caterham.

 

If I can't find it now I was thinking of just continuing to monitor it until the winter lay-up as it really doesn't look like something that is heading for an imminent major failure.

 

Any thoughts or other points to check?

 

Edited by - revilla on 6 Aug 2013 21:17:22

[Bob L]

Sounds like it could be the water rail or a leak from the hose that connects to this point. The water rail on mine is the lowest point where a leak from the heater hose could accumulate in drips and this is right above the starter area. Push some paper tissues around the area and try a short drive. That should at least narrow it down a bit.

 

[revilla]

Bob thanks that's a very good idea. I'll get the kitchen towel out at the weekend

[Wrightpayne]

Revilla,

 

loads in the archive about water rail leaks and the causes - bolts too long and forward fixing welded on in slightly the wrong place being the main culprets.

 

 

Ian

[revilla]

Yes Ian, thanks I'd looked at some of the historical stuff. I'll try to track down the source of the leak before it travels around the engine - if I can find exactly where it is coming from I'll have a better idea of which of the causes in the archives are likely to apply.

[David Lynch]

The gasket off the water rail to rear of engine is a good starting point. On mine coolant tracked all way to front of block and dropped near Alternator. Looked nasty but thankfully took a tiny cheap gasket to solve (well that, silicone hoses, new radiator and expansion bottle while it was in bits )

[revilla]

OK its looking like a minor failure of the water rail gasket at the moment, although I'm not 100% sure as having packed around the area with tissue and going for a drive to get it all warmed up, everything was still bone dry and clean when I got back. Looks like it only leaks when it feels like it! It's not leaking much anyway, I just checked the coolant level again and it hasn't noticeably dropped.

 

There is quite a lot of coolant staining around the bottom nut of the water rail attachment point and on the lip of the head immediately below it. There is also a lot on the bottom of the starter motor, which is where anything dripping from this point would likely end up. There is a very small amount of staining around the block/head joint on the same side at the front, but I think that's just a trickle creeping along the recess of the joint from the back where it's leaking. There are also a couple of streaks down the the block at points along the side of the engine, but looking carefully I think again it is water creeping along the bracket exhaust manifold and then running down (when the engine is cold, which seems to be when most of the leaking occurs).

 

I'll stick some pictures up when I get them off the camera.

 

I think I'll just keep my eye on it for now. It will be up for MOT in about 4 weeks and I'll probably put it into a Seven specialist like James Whiting as I want a couple of other bits looked into, so I'll ask for an expert opinion then, and if it is just a minor intermittent seep from the water rail gasket I'll replace it while the car is laid up for the winter (and take the opportunity to fit the bleed tee I have in the garage while I've drained it!).

[revilla]

Pictures:

 

Head Below Water Rail Gasket 1

Head Below Water Rail Gasket 2

Starter Motor Bolt

Front Of Head Gasket

Side Of Engine Block

 

What do people think?

 

[Mankee]

In the "Head Below Water Rail Gasket 2" photo, you can see where the leak is coming from the flange?

 

I had this same problem with my old-style water rail. It was fine with my old engine but leaked with the new one as soon as I started filling it up with coolant. The welding and flange was rubbish with respect to the water outlet on the head. But I've used two gaskets plus instant gasket, made sure that there is no tension on the front bracket and checked that the bolts don't bottom out in the head. No drips and smiles all round!

 

This was my leak. Proper gushing out.

 

http://images50.fotki.com/v1572/photos/8/42688/10523039/photo-vi.jpg

[revilla]

Thanks Mankee... As mine is barely dribbling I think I'll stick it on the "winter" list but I'll order a couple of gaskets in and monitor it closely for deterioration. Don't suppose you happen to know if the corresponding standard gasket from Rimmer Bros fits the Caterham rail do you? Not checked yet but expect the price will be a lot better without CAT.

[Mankee]

The part number PET10042 has been engraved into my head (the one on top of my shoulders, not my eninge) after having to order so many of them! It's a standard Rover part.

 

Rimmers' postage rates can sometimes be expensive for small items (I've used them a few times for bigger bits), but I've found a Land Rover place local to me in Manningtree who have been hugely helpful when I've needed random gaskets sharpish and needed them put in the post, even though I'm only 10 miles away. Try them out:

 

http://www.brit-car.co.uk/product.php/89424/0/gasket_thermostat_hsg_1_8l_pet_f_l

 

Good luck! :)

[revilla]

Yes I priced up ordering a couple on Rimmer and from your link and it would save me a few quid thanks. One for my list of useful contacts there! Cheers.

[Harry No Sheds Flatters]

I recommend you fix it sooner as it will only deteriorate and as we know K series do not like overheating. To delay the repair, which should not take much more than an hour, you risk a much larger repair bill.

[Mankee]

I would echo Captain Sensible's suggestion. Fluid leaks, however small, are not good. If coolant can get out, air may get in. Plus caring for the environment and roads by not dropping fluids etc.

 

It's worth ringing Brit Car and speaking to a human about postage as they are such small items and they may be able to do it for less than the website quote.

[revilla]

With a name like Capt Sensible, how could I not listen? Thanks for the advice, will order the bits and crack on with it.

[revilla]

Still worried ...

 

After a couple of hours blatting this morning I left the car in the garage, just went out it and took this picture. There was a clear droplet of coolant water oozing from the head/block joint below the water rail, but the water rail flange itself and the head above the joint was absolutely bone dry. I ran my finger around the bottom of the rail flange and there was absolutely nothing.

 

I can't make my mind up. This doesn't look like water that has run down from the water rail flange to me, it looks more like it is coming from the head gasket, however there is clearly some staining above this level towards the water rail as discussed above. I still have a nagging feeling that I've got a head gasket failure and the staining above it could be water that has been blown backwards from the failure while driving.

 

Mmmmm ....

[simonpa]

From the tracks of the dried coolant, it still looks like the leak is from the water rail.

 

I would maybe first try tightening the bolts (check the manual for torque settings) first and if still leaking, then change the gasket and see how you get on.

 

Cheers - Simon

 

[revilla]

Yeah I guess it makes sense to try the easy fix first and worry about the big problem if the simple fix doesn't work. Thanks for the advice and the reassurance.

[revilla]

Still worried ...

 

Changed the gasket on the water rail, applied some sealant and torqued it all up. The rail was a good fit, when the flange end was nipped up the bolt sat nicely on the bracket at the other end so didn't appear to be putting any strain on the gasket. The old gasket looked fine when removed.

 

On closer inspection, although the photographs appear to show streaks of coolant coming downwards from the water rail flange gasket, in reality there is very very little deposit there compared to along the head/block joint. After taking the car for a short drive, there is coolant again at the head block joint but tissue paper wrapped around under the water rail flange is completely bone dry and clean, apart from a tiny bit of coolant marking on the bottom (i.e. away from the gasket) which was clearly caused by the coolant droplets shown in the photographs previously spraying backwards in the airflow while driving; I think this is actually the source of the previously observed streaks.

 

In addition, there was a bead of liquid coolant sitting on the corner of the block at the front on the exhaust side as well as at the back where seen previously. Coolant is clearly leaking from somewhere and tracking along the channel of the head/block joint through capillary action. I'm now quite sure it isn't from the water rail gasket, and there is nothing around any of the hose joints or along the bottom of the rail itself, which is quite clean.

 

One possibility which occurs to me is that it could be weeping from the gland seal on the water pump under the timing cover (or even I suppose the pump gasket); it would have a bit of tortuous route from there up the head gasket but again could be carried around by airflow and if it was only a slight seep it may not be noticeably dripping as drips may get caught within the cam belt cover while stationary, so I think tonight I will whip the timing cover off and have a good look at the pump ...

 

Otherwise I can't really think of anything else other than the early stages of head gasket failure between the coolant channels and the outside . Time to re-read the workshop manuals, make up some liner clamps and get the spanners out.

 

If I do need to do the head gasket, I guess I it would be prudent to change the timing belts and therefore water pump and tensioner at the same time, so as long as I don't cock it up I'd change most of the other possible coolant leak points in one go. I've read Oily's comments on the Payen BW750 and BW5750 gaskets ... does anyone know how critical it is to fit the uprated oil rail at the same time? I've seen it variously rated as "optional" to "necessary", but would mean pulling the sump off as well.

[Grubbster]

Just something else to consider - on my last K series the water rail leak was actually nothing to do with the gasket but was in fact coming through the weld where the flange is welded to the tube. Just a tiny pin hole in it, so no amount of changing the gasket and applying sealant ever made any difference. May not be the case on yours but something to look into just in case?

[Bob L]

Take the capillary / tracking / wind effect out of the equation. Start it up on the drive from cold and dab tissue (dark green paper hand towels are ideal) round all areas while its getting warm. This should confirm the source.

[revilla]

Tonights efforts - I took the bonnet and nose cone off, removed the timing belt cover, wiped all damp areas dry, then ran it up to temperature while parked up in the garage, watching and testing with tissue paper for the emergency of water from any joints or gaskets ...

 

With the nose cone off, it was clear that water was appearing around the front corner of the head/block joint as well as the back corner (where previously seen), as shown here. This water had clearly been dripping and depositing coolant stains around the alternator mounting as shown here.

 

There was no obvious source of the water other than the head gasket. The line of the gasket just oozed droplets and both ends and the odd drip ran out from behind the exhaust manifold/clamp as shown here. If I carefully mopped the little wet patches away with tissue, they just became wet again. No steam, no squirting, no pressure in the cooling system (even with the fan cutting in and out I could take the expansion bottle cap off without any whoosh of air, bubbling or anything else).

 

The water pump, the area below it and the rest of the area behind the timing belt cover was clean and dry as shown here. The water rail itself and the front and rear hose connections, as well as the attached sensors and gasket were also completely clean and dry as shown here and here.

 

I also very carefully inspected the inlet side of the engine, which was as clean as the day it was made, so I don't think there is any chance that the inlet manifold gasket is leaking and the water tracking round the head gasket channel with the angle of the engine. Because of the angle of the engine, on the inlet side I could see the actual edge of the head gasket, which was clearly only a single layer, so I guess I still have the old original elastomer gasket fitted rather than the MLS and shim type.

 

As far as I can see that doesn't really leave me with any other conclusion other than a very small failure of the head gasket between the waterways and external face of the block on the exhause side, with the water then creeping along the gasket channel by capillary action and appearing at both ends and places inbetween.

 

Luckily it appears as though I have caught it early enough to avoid any further damage, as there are currently no signs of oil in the water or water in the oil or any other engine damage.

 

If anyone would care to confirm or disagree, please do so ... I don't want to pull my engine apart unless it really needs it. My plan at the moment is to pull it apart and fit the new MLS gasket and shim and new water pump and timing belts while I'm at it. What I can't decide is whether I need to fit the uprated oil rail too, which would involve pulling the sump too.

 

Thanks.

[simonpa]

From what I remember, Oily mentioned that the front nearside of the K had a propensity for leaking, due to the waterway close to the edge of the gasket there.

 

 

[tweeky]

isnt there some sort of presure test you can do ?