Broken Valve Spring

[cycleguy55]

I'd unbolt the motor mount on that side and jack the engine up enough to roll it a bit more upright and provide enough clearance to remove the head.

[eschaider]

Henry Ford once said, "If you need a machine and don't buy it, you will ultimately find that you have paid for — and don't have it!

OP, this is you in spades! On two different levels.

First,

That engine is not repairable in the car. Pull the engine and fix it!

Second,

Dicking around with all this touchy feely how bad is it hurt discovery stuff is the equivalent of needing the machine and not buying it!

In the end you will not have fixed the engine, still need to fix the engine and now have to begin the process of removal and repair.

Skip all the BS, pull the engine, clean the good parts, trash the bad parts, buy replacement parts and repair your engine!


Ed

[Dominik]

Well done on getting the head off. Had a stubborn Jaguar XJ6 head which took 3 days to pry off.

As above, do yourself a favour and take the engine out. Perhaps find an engine builder. You can do it yourself. Many others did, but do you really want to?

You might find an oddball piston, deck height, pin height, bob weight combo which will make you despair.

[ZOERA-SC7XX]

I've been following this thread and don't know why you just don't pull the engine. You will end up damaging the car by effing around with this in the car. You see now that you wouldn't be able to replace the head even if it was repairable with those studs, and there most likely is some other damage. Pull it and fix it the right way.

[Gaz64]

Originally Posted by eschaider

Henry Ford once said, "If you need a machine and don't buy it, you will ultimately find that you have paid for — and don't have it!

OP, this is you in spades! On two different levels.

First,

That engine is not repairable in the car. Pull the engine and fix it!

Second,

Dicking around with all this touchy feely how bad is it hurt discovery stuff is the equivalent of needing the machine and not buying it!

In the end you will not have fixed the engine, still need to fix the engine and now have to begin the process of removal and repair.

Skip all the BS, pull the engine, clean the good parts, trash the bad parts, buy replacement parts and repair your engine!


Ed

Originally Posted by Dominik

Well done on getting the head off. Had a stubborn Jaguar XJ6 head which took 3 days to pry off.

As above, do yourself a favour and take the engine out. Perhaps find an engine builder. You can do it yourself. Many others did, but do you really want to?

You might find an oddball piston, deck height, pin height, bob weight combo which will make you despair.

Originally Posted by ZOERA-SC7XX

I've been following this thread and don't know why you just don't pull the engine. You will end up damaging the car by effing around with this in the car. You see now that you wouldn't be able to replace the head even if it was repairable with those studs, and there most likely is some other damage. Pull it and fix it the right way.

I'm sorry to say that I 100% agree with the other boys above. Near 40 years as a mechanic, I would not attempt V8 head stud removal in situ.

The engine will need a full rebuild, there's no doubt. Don't try and do things by halves. The damaged head might be salvageable, the BIG question is whether the block is salvageable.

So now let's get set up to pull the engine out, put it on a stand, and do an inspection diagnosis during the pull down process.

[bobcowan]

As said above, you're probably going to end up pulling the motor anyway. The piston and block will be so damaged that you'll need to do some repairs there.

But sometimes it's easier to remove the engine with the top end off.

Take the nut off the stud. Unscrew the stud enough so that it is clear of the head surface. You can't remove it from the head, but that's OK. Use a binder clip or duct tape so the stud doesn't fall back in the hole. You can then separate the head from the block, and remove the head with the stud in the hole. Be sure and put the stud back in the hole before setting the head back in place.

It would probably be more difficult with a bolt in there, as the bolt head would be much larger.

Once out, you could probably shorten the stud by 1/2" on the block to make the process easier.

[splenderleith]

Hey everyone, I stopped posting once it became more of a cyber bullying event than giving actual valuable advice. You could certainly read through the posts to see what I am talking about.

Just a quick update: everything is fixed and in good working order. It was a pretty big job (for me), but you can absolutely service the heads while they are in the car. From this point forward, I will be checking my valve springs annually, to avoid these issues in the future. I had to replace both valves in the cylinder and I went ahead and changed all of the springs and seals on both sides of the engine. The machine shop removed the broken valve, replaced the guides and machined the valve seats. Some of the exhaust valve keepers were a bit difficult to break free, but I was able to get them to break free with full compressor pressure in the cylinder, a socket and a hammer.

I went for about an hour drive yesterday and another 2 hours today. Everything seems good and stable.

[cycleguy55]

Originally Posted by splenderleith

Hey everyone, I stopped posting once it became more of a cyber bullying event than giving actual valuable advice. You could certainly read through the posts to see what I am talking about.

Just a quick update: everything is fixed and in good working order. It was a pretty big job (for me), but you can absolutely service the heads while they are in the car. From this point forward, I will be checking my valve springs annually, to avoid these issues in the future. I had to replace both valves in the cylinder and I went ahead and changed all of the springs and seals on both sides of the engine. The machine shop removed the broken valve, replaced the guides and machined the valve seats. Some of the exhaust valve keepers were a bit difficult to break free, but I was able to get them to break free with full compressor pressure in the cylinder, a socket and a hammer.

I went for about an hour drive yesterday and another 2 hours today. Everything seems good and stable.

I take it the piston and cylinder walls were good in the cylinder with the bent / broken valve. Any photos?

Edit (2021-11-01): "Some of the exhaust valve keepers were a bit difficult to break free, but I was able to get them to break free with full compressor pressure in the cylinder, a socket and a hammer." Standard / common way to do this is using a socket that large enough to go over the keepers and press on the retainer. Giving it a good whack with a hammer usually loosens them enough so they can be fished out once the spring is compressed. A small, strong magnet is a great tool to fish them out.

[Gaz64]

Originally Posted by cycleguy55

I take it the piston and cylinder walls were good in the cylinder with the bent / broken valve. Any photos?

Yes, I'd like some photos as well please.

Interested in how the piston survived while it was kissed by the valve margin, virtually a knife edge.

And also the bare combustion chamber please.

Gary

[ZOERA-SC7XX]

You ask for help, then when you don't like the answers, it's 'cyber-bullying'? If you knew what you were going to do, why ask?

[splenderleith]

This is about the best one I got. Once I cleaned the top of all of the pistons, it was very difficult to find anything that looked bad. There were no scratches on the cylinder wall.

The machine shop thought that with the vast majority of the valve getting pressed up past the seat that there was minimal damage incurred.

[Gaz64]

Good to hear of your happy result.