Well I ended up getting one of the CRDs that I was looking at, that the PO expected needed a new HG. I was ordering parts to do the obvious things while trying to figure out what really is going on with the engine. I'd like to get opinions from the experts here, to see if what I am thinking makes sense.
PO had reported a slow coolant leak (going down in the res) and in one case a cloud of white smoke. He was thinking head gasket although the white smoke did not reappear but the coolant was still going down. No overheating or signs of oil-collant mixing, and no sign of exhaust in the coolant. Other issues I noticed were: A glow plug code for #2, and A LOT of oil up on the valve cover with it wettest with oil around the CCV. Otherwise the CRD ran pretty well the little I had driven it, no excessive smoke or other problems.
I did some initial checking for coolant leaks, and think I have found a good sized one at the thermostat-head connection, a bunch of dried antifreeze crust which was wet underneath when broken off. Great I thought I found the coolant leak. That was going to be my next fix.
Got new Bosch 5v GP's and was trying to put them in as the first step as I can't get tags until it passes emissions and it won't pass emissions with a CEL. I was also going to crank the engine while the GPs were out to see if any coolant comes out. Unfortunately the GP removal has gone pretty badly. I pulled #2 first as it was the one with the code. It came out and was sooty but complete, no problem. Hey I thought I was home free. But I ran into problems with the other GPs. #1 broke off just under the threads, the SS sheath that covers some of the ceramic and has the sealing cone is still in the head. #3 was worse, it broke off mid threads leaving the bottom of the threads and GP in the head. It's getting a bit hard to see in there, but #4 appears to have separated at the nut, so that when I spin it the nut and top part of the GP turn but the threads and lower GP do not, still all in there but 6 threads out. All in all a disaster. Not sure entirely what, if anything I did wrong. I had the block heated and warm, plenty of PB Blaster on the GPs, did not use excessive force. And I've changed GPs on about 8 or 9 engines before, without issues. Just not my day I guess
But if anyone has any thoughts as to what I did wrong or what 3 GPs breaking off might indicate in the engine, I'd like to learn from this if possible. Maybe a bunch of carbon inside the combustion chamber gluing thoe GPs in?
So I am making plans for a HG and perhaps a new head, and wanted to get the advice of folks here about some of the choices and what I can or cannot do given the state of the GPs remaining in the head.
1. I'm assuming that I should not move the crank until the head is off and any GP remnants are cleaned out of the cyl. Is that right, or does twisting the top off a GP necessarily mean the ceramic bottom part has broken free? Would it be OK to move the crank by hand to get the alignment pins in place or too risky?
2. I suppose when the head comes off it should be pretty obvious if there is coolant in any of the cyls. Even if not, it still leaves the question of does this head have a small crack in it someplace which caused the white smoke every so often. Does it make sense to try and salvage this head or go with one of the reconditioned heads from VM in GB? What do folks think and what's their experience with those heads? It seems that the reconditioned head from them is about the same price (or maybe even less) as one would pay at a machine shop to do the work on the old one.
3. Also be interested in hearing if new valves or maybe just exhaust valves would be good insurance. What do folks think?
4. I hadn't really expected the GP job to go this badly (or really badly at all), and thought that I'd have a running engine now to figure out the oil slick on the top of the valve cover. Might be as simple as a bad CCV or its gasket. In any case I'd like to get a handle on that before throwing a bunch of new parts and my time elsewhere on this engine, possibly in vain. So again, any thoughts from the experts here: The valve cover is covered with oil and attached dirt, mostly on top, worst around the CCV but the oil goes over to the drivers side and quite a ways to the front. One other place I found oil was the EGR tube which goes to the intake elbow. I removed that to get GP access, and noticed a bit of oil coming out of the ERG (or is it the cooler there) when the tub was freed. Any thoughts about what might be the cause of this oil and what it might mean about the state of this engine. (BTW, I did confirm this CRD has the GDE eco tune)
5. I'm assuming that along with the HG and new head (or rebuilt one) I'd be putting in the usual, new TB and kit, new WP, new rockers (no noises but at 140K miles). Any other parts that I should be replacing?
Thoughts and diagnosis of what's wrong all appreciated.