Big coolant \'leak\', then pressure test found no leak

[teabagger]

Hey,

I\'m running Stu Wilsons FD. On Friday the coolant level alarm went off just as I switched the engine off, popped the bonnet and coolant was all over in the general area of the expansion tank. It also looked like it could have sprayed coolant further back and low down but it was hard to tell. Power FC topped out at 115 degrees water temp.

I\'ve just had the system pressure tested at Barr-Tech at 1bar and they can\'t find a leak.

Nino at Barr-Tech reckoned that it could be a sign that the head gasket is on its way out. They flooded the engine when moving the car around and had to take the plugs out, there is the possibility of water on one of the plugs but he didn\'t sound too sure about it. If the head gasket was a problem would it be really obviously noisy when the engine was turning from a cold start? (just had the head gasket go on my Seat and it sounded like a tractor when started from cold until the crack closed up).

The one thing I can think off is that about 2 mins before my problems on Friday I went over a *really* rough bit of road that heavily jolted the car. I wonder if this has just lobbed a load of coolant out of the expansion tank.

I\'m having the coolant checked for hydro carbons to see if there are more serious problems.

Anyway, I was just wondering what peoples thoughts were on this and I suppose a bit of reassurance that everything will be o.k and I can have my baby back on the road soon.

[MillSpeed]

For a start you wanna take it to a garage that knows rotary engines don\'t have head gaskets! :Laugh When you say expansion tank, do you mean the one ahead of the O/S front wheel or the AST by the intercooler? 115 is goin a bit, is the car showing any signs of coolant seal failure? (pig to start, persistant clouds of steam coming out of the exhaust, bubbles of combustion gasses rising to the top of the coolant in the filler neck)

[teabagger]

For a start you wanna take it to a garage that knows rotary engines don\'t have head gaskets! :Laugh

Man I feel like such a newb. They were the only high performance guys nearby when I had probs on Friday. They\'ve got a really good rep, but they\'re not rotary specialists.

When you say expansion tank, do you mean the one ahead of the O/S front wheel or the AST by the intercooler? 115 is goin a bit, is the car showing any signs of coolant seal failure? (pig to start, persistant clouds of steam coming out of the exhaust, bubbles of combustion gasses rising to the top of the coolant in the filler neck)

Yep I mean the expansion tank, in front of the driver side wheel arch. Car has been running sweet up until this. No problems on start, though I noticed a small amount of smoke on start the other day. It went well within 5-10 seconds (this is normal levels isn\'t it?), exhaust doesn\'t smell of coolant on start just like it\'s running slightly rich until it warms up which is o.k. Still waiting for results on hydrocarbon test, am I correct in thinking this should put the water seals in the engine in the clear if it comes back o.k? Am going to order a new AST cap and replace that anyway.

I\'m hoping that the jolt chucked water from the expansion tank, then after I slowed down coming into the village it drew air back into the AST when cooling and caused the increase in temps then the level warning kicked in.

[teabagger]

update...

hydrocarbons present in cooling system

clarified the water/sparkplug thing, apparently one of the plugs was damp.

suggestion that this excess presurised the system when hot causing it to overflow from expansion tank.

Am I right in thinking it could be either a water seal gone in the engine or even just could be a case of replacing the AST cap?

[MillSpeed]

Yeah, a bit of smoke/steam on start-up is pefrectly normal provided it clears within a minute or so. The hydrocarbons test should be a good indicator to the health of the coolant seals. Wouldn\'t hurt to just pop the coolant filler cap (on the engine) off whilst cold and look for any bubbles. Sounds like you might have spilled some of the water in the overflow tank like you say, how full does it get normally? Changing the AST cap is always a good place to start if the expansion tank starts overflowing.

EDIT: Just read your post, hydrocarbons could be the early signs of seal failure if the other symptoms aren\'t present. I would\'ve thought that if enough water was leaking into the rotor chambers to wet the plugs it\'d be a b*tch to start. Change the AST cap and see what happens.

[nikp]

Early water seal failure won\'t make the engine hard to start. And seeing as though there are hydrocarbons in the coolant, then unless someone knows better, that is a sure sign that the water seal has gone in the engine.

[teabagger]

When they pressure tested the system today it didn\'t lose any pressure at all, I\'ve been chatting to Stu on the phone about this and he seemed to think that if it maintained pressure then the seals were good. Also he said there was a possibility of coolant contamination when work was done on the turbos.

I need to take the spark plug out again once it\'s cooled down and look for any signs of water/coolant on it to rule out the possibility of some mistake. When they said they\'d noticed it they\'d taken it out because they flooded the engine while moving it around. It\'s a bit late to order an AST cap today, I\'ll sort one out tomorow. On the only occasion I noticed any smoke on startup there wasn\'t that much and it cleared in under 10 seconds.

In the meantime, is there anything I should/should not be doing. I\'d planned taking it to Norfolk at the weekend (180 mile or so round trip) is this a bad idea until I know more?

I\'m very new to all this, as you can no doubt tell, so thanks for all your help!

[MillSpeed]

Hmmm, I wouldn\'t be taking it too far from home until you know for sure what\'s happening. If you do venture out make sure you\'ve got plenty of pre-mixed coolant ready in your boot in case you\'ve got to top it up. As a stop gap, you can get the AST caps from halfords or any good motor factors. It\'s the same cap as on a Mazda 626. Should really get a 0.9bar cap if you suspect coolant sael trouble, but I run a 1.1bar cap off a 1.8 626 and I\'ve never had any problems. Have you checked for \'champagne\' bubbles in your coolant filler neck?

[teabagger]

Have you checked for \'champagne\' bubbles in your coolant filler neck?

Not yet, light was getting a bit too low by the time it had fully cooled last night.

I forgot to mention, the coolant level warning buzzer had stopped sounding without the garage having to add any water/coolant mixture, I thought it didn\'t seem to have lost a huge amount of liquid at the time. I think it probably took around two mugfulls of liquid to top it up. (I did this three times to allow it to work through).

I\'m ordering a new AST cap today and some breakdown cover
The engine was only rebuilt less than 25K ago so I\'d hope the water seals were fine. Will be taking it out for an hours drive tomorrow night to see how she goes.

[ds2000]

It could just be the AST has a hairline fracture thats only showing itself when hot.

Definitely get a 100% answer on the seals.

Hopefully for you its not bad