Please help,

I have a 1993 Import WRX 2.0Turbo (VF34) in my 1963 split screen camper. It's been in there for over 30K miles so the installation is well tested with no overheating problems.

I bought the engine from a breakers which was unknown and fitted it to my 1963 Splitscreen campervan, I've been happy motoring with it and it made 305BHP not that I use it all.

Now recently on two occasions i found my header tank completely full to the top and evidence of it spitting out at the top over the pressure cap. Somehow I think there is air in the system, I can sometimes hear gurgling sounds after a run, the engine does not overheat and there have been no temp fluctuations. I have started the van from cool and the coolant level dropped 2" straight away and it went back to normal levels overnight.

It has happened again today, I replaced the coolant 1500 miles ago and now it has a darker colour to it compared to what I put in (pink stuff).
If you massage the flexi pipes the coolant goes down as the air is bled out, I can't find any leaks anywhere, I replaced the thermostat and water pump 20K ago the rad is brand new as is the heater, all coolant pipes are new as well.

Any ideas, I'm going to have a sniff test done next week.

 

sniff test then see

 

Are you running an under-slung radiator ahead of the engine - if so, it can be a pain to bleed the system.

Mick

 

Yes I am, it is the same design concept as a Lotus Elise, the Rad is sealed off there is no pressure cap on it, the pressure cap is on the header tank.
I'm pretty sure it's bled but I take your point.

I drained some of the coolant out last night and compared to new stuff it's gone slightly cloudy with a very very slight dark / dull look to it when you compare new with the coolant that's done 1500 miles, would this be expected ?

Is it worth doing a leak down test ?

 

Sounds more like an airlock.

 

Sniff test...ask a decent garage to do one, it tests for hydrocarbons in the coolant, cost a couple of £ to do, peace of mind.

 

I just drained 250ml out of the header tank (when cold) to get it back to the max cold fill level, been for a 10 mile drive and the tank was full to the top again.

 

I agree now, but how's the air got into the system, the systems been fault free for 1500 miles (since I filled it up) if there was air in the system i would have thought that this was well gone by now,I'm concerned that the coolant looks dull and cloudy as well like it's been stained with exhaust gas.

With no visible leaks I am assuming the worse which could be a gasket breach from combustion to water.

 

Where are you measuring this level to drain 250ml out?

It refills itself because when it gets hot the coolant expands.

The air has got in because someone refilled without checking "how to" on here. Very easy to airlock, impossible to bleed.

 

sniff test, get it done to rule out HG failure.

 

I have had two sniff tests done at two different garages and they both came up with the same result which was negative HC's in the coolant.

 

As above^^^^^

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