Hopefully you’ll be able to give your opinions.
Have a 2007 CRD zd30 wagon.
Had a recent service where they noticed there was foamy gunk under the radiator cap. They did a test and found exhaust gasses in radiator fluid but no oil.
Not losing any fluids noticeably
Oil is black as midnight
Exhaust is clean
Never noticed any sort of loss of power
Normal fuel consumption
EGR blocked ages ago
Heater core possibly blocked as gear only lasts a few seconds
They suggested head removal and recondition. What are Your opinions on this? Are we thinking gasket or head?
Would you go ahead with this work or leave it until more signs?
any other suggestions?
Have been watching this without commenting so far, mine is a DI but that doesn't really make much difference, your description is the same as mine was for quite a while, I did test after test but nothing showed except ongoing movement with coolant levels, just variations, no loss. I drove it for several years like that with no issues whatsoever, but I knew something was wrong. One day I had just come back from a hard drive and after turning engine off I walked past the passenger side front mudguard and heard a bubble, lifted bonnet and saw very minor bubbling into the lower plastic surge tank. That was it, head to come off.
What I found was a minor weep between 3 and 4 cylinder, looked like it had been there for quite a few years, what had developed later was the weep extended to a small water gallery between 3 and 4 just off to the passenger side, this was just enough to pressurise the system to the point it pushed coolant into the lower bottle but would suck it back as engine cooled. No overheating was assocciated with the fault. I had pressure tested the system many times (made my own), a sniff test was done and passed (but they are unreliable on a diesel anyway), coolant was fine. I have had mine 23 years and always regularly looked after coolant (at the time the old girl had done 380,000+ K's) when I took the head off I also saw cracks running out from the GP holes, regardless of what is said by some, minor cracking there causes no issues, there are no water gallery's in the vicinity. I took the head to a specialist to get it cleaned up and valve ground and camshaft clearances done, as it turned out he was able to get me in a new head with valves for not much more than it was going to cost me to fix the old one so I went for it.
They reset everything on the head, after cleaning up the block face and ensuring there was nothing untoward I fitted it. Followed the genuine workshop manual (the one we have stored on here) to the letter in all the steps of retightening the head, complicated. I did take the final step to the maximum seeing as I run 24-25psi boost. I now use 10Tenths Race Coolant (and love it) and I'm up on 428,000k having done many more trips since the head and gasket change.
On a sidenote, because I had always looked after the coolant system the water pump looked like new, so it went back in.
My 2 cents worth on my experience.