Thread: 4.0L Rover V8 Valvetrain Carbon Buildup

Wow...might have been mistreated before you got it?

Cheers

That's pretty much what mine looked like when I replaced my head gaskets. Not sure why, as had never overheated to my knowledge. Perhaps the magnatech 10W40 isn't up to job. I've been thinking about changing to Penrite semi synthetic just in case.

I'm guessing the change periods are too long, although it's quite probably limited detergency/dispercency with the oil too.
Basically not enough detergents and dispersants in the oil's additive package.


There's an oil additive available from the US that will slowly soften and remove the bulk of that over a couple of thousand km.
It's a lanolin ester based product so is safe to use and won't result in big chunks breaking off and blocking oil galleries if you are interested.
I haven't used it for years, but a couple of very clever blokes I know in the US have tested it and said it definitely works, unlike most any other additive.

I do 5000k oil and filter changes. These old design of motors like it. You might not have problems if the vehicle was used a lot for highway runs but for less than that 5k is the way to go in my view. I don't care what the book says...with manufacturers it's all about reducing their costs and selling the vehicle as low maintenance (!! - until it's out of warranty...)

Cheers

Andrew, I used to do 10,000km OCI's with the warm 351C in my old F100, but it was running LPG 99% of the time and Mobil 1 15W-50.

It was spotless internally.

As you inferred, usage is very important to determine OCI's.

Lots of short trips, stop/start city driving.
Bring the oil change interval right back.

Rick the LPG does run clean! My D1 is still on LPG 300k klm original motor untouched and my D2 had injected LPG for 100k klm. You had to change oil by the numbers not colour on the stick as it was always light honey.

Cheers

Yep, that was what the old cabbies used to tell me when I was a kid, and my own experience bore it out.
I think the only potential issue with LPG was nitration of the oil? (And valve seat regression without hardened seats)

I only ran petrol in emergencies.
It was either Shell 98 or Avgas with octane booster.
The comp ratio was silly, but it worked.

Originally Posted by ozscott

Wow...might have been mistreated before you got it?

Cheers

I agree, With that much build up I suspect that this motor has missed out on regular oil changes.