Following on from a previous thread..
Now 5 weeks since buying STI Spec D
Has had:
Dipper tube "mod" to expansion tank
New thermostat
Engine out and new head gaskets (which HAD failed)
Continues to bubble air into expansion tank
so:
New water pump
New caps for header and expansion tanks

MKar in Rochdale have no idea what else to do
Any suggestions?

 

Airlock? How have you been filling it? Is it overheating?

 

Cracked head maybe?

 

It's with M Kars (scoobie Main dealer, Rochdale)
they have done all the above work.
I think the original haed gasket failure is indeed secondary to an air lock caused by whatever is blowing bubbles into expansion tank.
heads were crack and pressure tested before being "faced" to remove surface marking
Water pump was replaced as, apparently, seals can suck in air at high rpm if there is even slight wear on shaft bearings

Here'sthe whole sorry story from the start...


Picked the car up from Redline in Knarsborough 5th June.
I live in Preston, and the car boiled before I got home
Limped last 5 miles in 3 hops so as not to get it TOO hot
It dumped its coolant onto my drive from the expansion tank.
allowed it to cool, topped it up (warm water) and drove 1/2 mile up the road.
Boiled when i got back ,coolant dumped again.
Rang Redline, very apologetic, agreed car must be faulty, but asked that we try and find out what was wrong before giving money back. Claim to "know" the car, and believed it kosher...
They arranged beaver tail for next morninbg which brought me a Diesel Mondeo(!)"courtesy" car ,and took my Spec D to Subaru Main dealer.
The first two "fixes" did not stop it boiling, but the head gasket change has (they say)
However, it still has air bubbles coming up in the expansion tank once it is warm
These are "less" since the water pump change, but it's still happening
Don't think it can be right!!
And neither, it seems do Subaru UK
rest as above...

 

Prosport in Stockport, 0161 432 9999

Tony

 

Need the cooling system pressure checked again IMO (assume its been done before? ) to asstertain the system is water tight.

Cylinder leak down test may help too.

Could be anything from a cracked cylinder liner to a tiny hairline crack in the radiator end caps or heater matrix (which is possible since the engine did overheat and over-pressurise, which causes secondary damage).

 

I've had intermittent problems over the last 2 years on my Spec D, with the expansion tank filling but not getting syphoned back into the system.
I think I've recently found the cause - the rubber pipe that enters the expansion tank is push fitted at the other end. This was pretty loose and I believe that when the coolant cooled down, instead of syphoning back the overflowed coolant, it just drew in air.

Next time the car was started, I would get a bubbly sound from the heater matrix (air lock) and the expansion tank would gradually get fuller and there'd be a few air bubbles.

Suggest you cable tie or clamp the push fitted end and bleed the system by pulling off the radiator and turbo returns to header tank, squeeze top rad pipe and then putting thumb over each pipe to remove air lock. Also start car up for a while with rad cap off and put heater to high heat.
Put cap back on and repeat bleed process as above while topping up header.

When you say the car boiled, what happened? Gauge go into the red?


BTW, what is a dipper tube mod?

nick

 

Dipper tube mod is exactly what you describe..
The tube which delivers coolant into the expansion tank sucks itslef to the bottom of the tank, so that it can't "refill" the system as it cools. If (as you found) there is a loose fit anywhere, you get air sucked in instead!
There is a mod for (as I understand it) the bottom of this tube to prevent the problem

thanks for all the help guys..

I called "enough" today, and Redline are going to give me my money back.
Another Spec D to look at in Cheshire on Monday.

If anyone thinkink of using M Kars in Rochdale, I wouldn't bother..
they haven't got a clue!!

Mark

 

Mark, thats why I use Prosport in Stockport

Tony

 

Is it called "snipping the end off the dip tube"
Also found the expansion tank filled up a lot of sludge until the first coolant change - this doesn't help the syphon effect either.

Good choice of car BTW