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[brian36]

things only get worse my car in trouble wife just comes in and says a guy just ran into her, bumper gone front wing gone headlight and fog light gone,aah the joys of motoring,guess I won't get to borrow wifes

[car5car]

If valve is bad, compression is usually 0.
Wet compression test should be done and I would flush engine by ATF to clean possibly stuck rings.
Mechanic cannot see anything if compression is 75. If valve is bent pretty bad, he would see it.
Usually all good exhaust valves have pitting.

[Gaffers]

My experience of burnt valves is that they actualy result in close to zero compression, and the compression test hints at a bit more than this. Never seen one on a V6, what year is it?, any sign of stem seal issues?

Also, having used endoscopes in the past, not sure how he got a view of the valve seat when poked in through the spark plug hole (small entry hole and having to view something behind the entry hole in a very small and confined space).

As already said, get it to Nottingham and leave it on the drive and I will have a fiddle.

Brian - that's an offer you really shouldn't refuse.

Agreed

plus infinity, Mark really is the guru and master on these motors 

[Webby the Bear]

My experience of burnt valves is that they actualy result in close to zero compression, and the compression test hints at a bit more than this. Never seen one on a V6, what year is it?, any sign of stem seal issues?

Also, having used endoscopes in the past, not sure how he got a view of the valve seat when poked in through the spark plug hole (small entry hole and having to view something behind the entry hole in a very small and confined space).

As already said, get it to Nottingham and leave it on the drive and I will have a fiddle.

Brian - that's an offer you really shouldn't refuse.

Agreed

plus infinity, Mark really is the guru and master on these motors 

+1 

Camera down in the cylinder. I've never even heard of that.

Anyways, the cost to rebuild is pretty low in terms of parts and I saw it as a good opportunity to renew lots of gaskets and seals. and now shes running sweet!

[brian36]

thanks to all,mark will have a dabble when we can arrange thanks to all

[henryd]

My experience of burnt valves is that they actualy result in close to zero compression, and the compression test hints at a bit more than this. Never seen one on a V6, what year is it?, any sign of stem seal issues?

Also, having used endoscopes in the past, not sure how he got a view of the valve seat when poked in through the spark plug hole (small entry hole and having to view something behind the entry hole in a very small and confined space).

As already said, get it to Nottingham and leave it on the drive and I will have a fiddle.

Brian - that's an offer you really shouldn't refuse.

Agreed

plus infinity, Mark really is the guru and master on these motors 

+1 

Camera down in the cylinder. I've never even heard of that.

Anyways, the cost to rebuild is pretty low in terms of parts and I saw it as a good opportunity to renew lots of gaskets and seals. and now shes running sweet!

Its a bore scope Webby,very usefull bit of kit for some applicazione but as usefull as tits on a boar for checking valve damage through the plughole

[Marks DTM Calib]

So this car is now on my drive and the drivers head an hour or so away from removal.

This has been a challenge, the previous cambelt change must have been done by a gorilla as the fixings are rounded and hugely overtightened plus some threads buggered.

On top of this the cam timing is a tooth out.

And to just do and things off, the heads have been off before and some brackets are missing, some cam caps fitted the wrong way round and the can seals not fitted correctly so were leaking.

Head finally off tomorrow hopefully!

[omega3000]

Nothing like a challenge eh  Amazing how some of them even run 

[terry paget]

Enthralling thread, gentlemen. I take off my hat to all you learned engineers with your experience and wisdom. I haven't taken a head off a car since my Ford Escort days, that was a simple push rod job. Nowadays modern materials and rotating valves make it rarely necessary.

Good luck to all, and keep the story coming

[Webby the Bear]

will be good to see a correct diagnosis! if its a tooth out.... bent valve perhaps?

[terry paget]

I do not think one tooth out would cause damage. Two teeth out cause clattering, engine still runs, but no lasting damage. I imagine three teeth out stop the engine.

[Webby the Bear]

I do not think one tooth out would cause damage. Two teeth out cause clattering, engine still runs, but no lasting damage. I imagine three teeth out stop the engine.

Ralf (my old PFL 2.5 v6 mig) was 5 teeth out. and still ran 

[omega3000]

I do not think one tooth out would cause damage. Two teeth out cause clattering, engine still runs, but no lasting damage. I imagine three teeth out stop the engine.

Ralf (my old PFL 2.5 v6 mig) was 5 teeth out. and still ran 

For a while 

[Webby the Bear]

Also thinking about it.... I think it's perfectly reasonable for a valve to be bent if a tooth out. thinking about how close they are together (pistons and valves).

[Marks DTM Calib]

But a single valve on a single cylinder with a tooth out?

In reality a single tooth wont cause valve impact, and the heads still not off, some arse has used standard nuts on the front pipe to manifold connection and rounded them off, got one off but the other needs cutting.

Getting quite a list of bits needed here, thankfully I have some already