Advice needed........

Hi did the valve clearances today and checked over the engine - oil,coolant level etc....

Noticed with the engine running i am getting tiny bubbles in the coolant expansion tank they are around the side of the tank - no sign of any oil in the coolant at all, no white mess in the rocker cover or dipstick.

Am i right to suspect the head gasket??

Daz

Was it hot?

Nope hasn't overheated since i've had it - have replaced: thermostat/heater matrix/top rad hose/new coolant/new tank cap it always runs in the middle of the temp gauge and my 2nd gauge and sender thats in the top rad hose indicates when the thermostat opens and the temp of the coolant passing through to the rad. It reads at just over thermostat temp.

Daz

Just thinking that gases are getting past the head gasket and into the expansion tank - can't see bubbles appearing in the tank just tiny bubbles around the inside of the tank

Daz

If you cant see them appearing I wouldn't worry to much, sometimes after water is agitated small air bubbles might stick to the sides, if you see them appearing alot then it might be something more

If the head gasket is leaking into the coolant when you start it from cold it would pressurise quickly and sometimes you can smell exhaust fumes in the expansion tank, or you can do a sniffer test with the right equipment

Yep might have to see if a local garage can do a sniffer test to answer that question, but it doesn't pressurise quickly.

Been looking on ebay for new gaskets and bolts, spotted a reconditioned head thats been acid cleaned/skimmed/pressure tested hot with new valves/valve guides/valve stem oil seals and valves ground for a good seal and 12 months warranty.

Daz

DISCOVERY1-DAZ said:

Yep might have to see if a local garage can do a sniffer test to answer that question, but it doesn't pressurise quickly.

Been looking on ebay for new gaskets and bolts, spotted a reconditioned head thats been acid cleaned/skimmed/pressure tested hot with new valves/valve guides/valve stem oil seals and valves ground for a good seal and 12 months warranty.

Daz

Click to expand...

Sounds expensive and maybe not needed, if you do find combustion gas is getting into the coolant have your head pressure tested, it should be ok if you haven't over heated it....hopefully

Yep not sure how much it costs to get the head skimmed/tested not sure where i can get it done round here either

Daz

does it need skimming ,testing i wouldnt bother with just check face for cracks they are allways visible

Its not overheated so i'm just wondering if i can get away with a gasket change?
Haven't got the head off as i only noticed the tiny bubbles today.

Never done a head gasket before so not 100% on what i should look for??

Daz

now, it's friday night.. so y'know BUT..are you sure you aren't being a big drama queen? AFAIK if you had a serious head gasket issue then the coolant level would be waay over level.

Nope don't think so..................
I'll get it sniff tested and go from there.

Cheers
Daz

300 tdi ? id whip head off fit new gasket its bound to need doing unless it has recently

Well it has done 190k so yep probably does need doing - any tips on doing it james??

Cheers
Daz

But if it aint broke.....

mark-d said:

But if it aint broke.....

Click to expand...

Yep thats the BIG question........... is it or isn't it??

I'll get the sniff test done tomorrow morning hopefully and go from there

Daz

remove brass bung on lh side just in front of down pipe ,to drain coolant ,remove inlet manifold undo exhaust manifold head can be removed by just pulling turbo away while still piped up ,with a disco 2 rear bolts cant be removed or refitted with head on so use magnet or similar to hold bolts up injectors can be left in ,torque setting is when doing bolts up one bolt flat is 60 degrees just mark head and bolt ,and also mark bolt so you know its been done after each

mark-d said:

But if it aint broke.....

Click to expand...

at that mileage id do it ,£10 for head gasket alls that needed others can be reused if you want to save cash with no issues

Thanks for the info James

Cheers
Daz

UPDATE: phoned the garage to ask about a sniff test and they wanted to charge £30 so i've bought a proper kit to do it myself off ebay for £25

The kit includes everything needed and a big bottle of the special fluid

Daz