1/2 an oily towel

[Sheepdip]

Ferd - I might join you, maybe we could get one brilliant car out of two...

Started to look at second engine rebuild after first rebuild expired when jackshaftseized due to disintegrating waterpump gears after 1800 miles. Block has been repaired and looks good so time to look at the heads - could see a couple of Z shaped valves in LH head but cam turned ok.

Stripped valves out, nr 3 had cracked guide, then noticed condition of combustion chambers -the first one (ie nr 2)looked different to the other 3 ( I have scraped the carbon at the top)- is this head gasket failure? I've never had one before - and the heads were skimmed and rechecked before fitting.

Then tried cam in head without valves to make sure seizure hadn't dried up the oil supply. It had a couple of tight spots but turned - narrowed it down to nr 4 cap. Tried RH cam safe affect. I did remove the dowels and studs for refacing but all seeded ok on assembly Adjacent valves 6 & 7 had strangely peeling carbon on back so may have been like it on first rebuild - any ideas why or what to look for?

Not sure I can look my wallet in the eye if I have to visit the machine shop again - this engine has cost mea fortune in last 12 months, I still love the car butRover V8's are starting to wink at me as I pass the scrapyards.


Paul

[GDPR]

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Carbon peeling onvalves commonlyis where they are getting wet,sometimes through coolant down the inlet throat but more commonly oil down stem seals.

Not a hard and fast rule, but that was my experience of 21 years....

Russ:dude:

[Sheepdip]

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Hi Russ, thats an interesting idea that I hadn't come across before. I haven't checked the guides as was going to get them all replaced anyway along with new valves just in case there was unseen damage. I'll have a look.

Cheers.

paul

[Ferds]

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Hi Sheepdip!

Sorry to hear you are also experiencing some issues...

I agree with Kryten on this one (is that a good thing, given my luck???). :?

Having said that, I do have ideas about an uprated Rover V8, but it seems there is a lot to sort out before we get to that stage!

Good Luck!

Chris

[Sheepdip]

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Maybe all is not lost. Had the head inspected. The camshaft has light chatter marks on the bearing surface which may account for the problem - I've been recommended to lightly emery the camshaft bearing and see how it goes. Also the head gasket had failed - but not sure why, head is flat. He agreed with your diagnosis Kryten on the flaky valves and also reckoned the engine had got hot. So one valve and guide might be the lot fingers crossed.

This might make you think twice about where you leave your precious heads. My machine shop told me they'd been broken into recently and all the aly had been targeted and taken before being disturbed. That included several rebuilt quality engines, cylinder heads and stuff waiting to be worked on. Now they find everythingsinsured except customer stuff......they've had to pay out from their own pockets. I was told if I left anything it was at my own risk until sorted.