Thread: 3.9 Rough on startup when cold but fine when warm

So it appears that this is a blown cylinder head gasket. I have been keeping a very close eye on engine temp amd I am hoping that the damage is not extensive. I am trying to work out now if this is in any way related to the heater core packing it in and dumping coolant into the cabin some weeks back. The car was idle for 4 weeks whilst I was in the UK and the coolant usage is now apparent on my return.

Interestingly the original symptoms have reversed to a degree. Roughness up to 60kmh followed by smooth running has been replaced with rough running when hot over 50kmh. I am obviously 1 cylinder down and there is some mechanical noise from the right bank but I cannot hear the clicking of a slipped liner. The smell of coolant from the exhaust wasn't obviousness at first but is now pronounced when warm.

Off for a strip down and examination tomorrow. Time will tell what the damage really is.

Compare the plug colours, coolant in a cylinder will generally stain the insulator a funny colour. If the problem is at one end or the other of the block, a head gasket is likely. If the offending plug comes out of the middle 4 cylinders you have a cracked block or head.

Bugger Bigdog.
I was just thinking about PMing you to see how you got on with the cold start stuff.
Probably overheated when you lost the coolant. It had never been overheated in the previous 13 years or before AFAIK as I talked to the first owner, although the digital temp monitor should have indicated the actual temp, as it is dry.

It has Triumph Rover Spares super duper head gaskets on it which cost a bomb, but stopped coolant drools out of the head ends , which were there with the Ehlings. It has ARP head studs so you have to take the nuts off the LH head then undo the studs with the hexes in the top of the studs. I cannot remember if you have to do it with the right head.
The heads are the last iteration of 4.6 heads which I bought from TRS.
Any questions please PM me
Regards Philip A

Thanks PhilipA. I was very conscious of the temp when I lost the coolant. I don't think it went past 104 and the standard gauge did not move much and certainly didn't light up, however the heat sink effect after I stopped the engine, especially with low coolant, I didn't monitor. I had a tip tray ride home after that so there was no running on empty. However it looks as if the damage was already done.

Such is life with a 22 year old car. I am getting my local mechanic to look at it tomorrow. He is not a rover expert but he has experience of rover 3.5 V8's, both normally aspirated and supercharged so he might know enough. I guess we need to know what to look for and what to expect? Warped heads as a minimum? Anything else that we should look for? What should we replace as a precaution with the top end stripped?

Maybe time for a TRS 4.6 bottom end if I have slipped liners? Thoughts?

I really doubt that it would have a slipped liner given that it has never been over 102 degrees ( and that was for a moment climbing Mt Pinnibar in summer and the rad fans then cut in and it went down) , so hope for the best that it is just a blown head gasket. although the engine would typically rise at least 5C-8C on heat soak and maybe even more.
I am pretty surprised considering the lengths I went to to try and ensure that it never got hot. I think you should hope for the best and think head gasket but plan for the worst.
A 4.6 would be nice but was out of my price range and you should perhaps think about the 240KK transmission.
Regards Philip A

It appears that This is too big a job for my local mechanic. So I am now looking for recommendations on who to use around the Sydney upper north shore area. Particularly some one within 10-15 kms of Hornsby.

Is anyone able to let me have the name of a reliable mechanic that I can contact? I am loathe to use someone new without a reference.

Cheers.

Ayers at Brookvale have a good reputation phone 99056048 .

British and Swedish at Narrabeen have done work on that car. If the ownership is still the same , the son was pretty good on Land Rovers.

I intend to have Ayers do the LT230 input seal on my D2 soon.
Regards Philip A

Any views on Davis Performance Landys ? I also have a recommendation for them.