Stuck broken valve

[Mpgp1999]

Hello

I am trying to get this 25 sedan running. It appears to be all original. I have a bent and broken valve. The motor became stuck on the valve. I don’t want to damage the camshaft. Any suggestions to remove it?

Edited January 25, 2023 by Mpgp1999 (see edit history)

[Minibago]

Remove the tappet covers

Remove the offending valve retaining pin, cup and spring.

Cut the valve stem at the base of the guide.

Remove the cam follower and plug the hole in the block.

Try to (Carefully) prise up the remaining valve part.

Perhaps using two screwdrivers.

A piece of flat aluminium plate under each screwdriver might act as a cushion on the valve seat but you may find you need to replace the valve guide and recut the seat.

If it will only come up a little way then cut the head off and drive it down 

Good luck.

[Mpgp1999]

I tried the screwdriver method. Even tried a pry bar. No luck. I will try cutting the stem. 

Edited January 25, 2023 by Mpgp1999 (see edit history)

[Minibago]

Hopefully the valve is bent below the guide and cutting the lower portion of the shaft will do the trick.

I take it you have already removed the spring and cup? 

If the cam shaft is jammed on and the cam follower is hard up against the valve then perhaps try to rotate the engine backwards a little to ease any pressure.

Back off the tappet adjustment to allow for clearance to remove the cam follower and spring.

[Mpgp1999]

I started out using a piece of wood, but I slowly started using more and more force until I made it worse. As far as rotating the engine backwards, do you think I could just jack up a wheel and turn it backwards in gear?  The motor only needs to spin backwards a quarter of an inch just enough to take the pressure off the camshaft. 

[Minibago]

Spring steel 1/2 mm thick is available in small sheets on ebay.

I bought some and I thought with judicious use of a grinding wheel I should be able to fabricate some. I just need to get a round tuit.

 

[Minibago]

My apologies

wrong thread

 

😱

[Mpgp1999]

I was able to remove the valve retaining pin. I also moved the motor back so pressure is taken off the camshaft. I tried hammering it in to break the rust free but that did not work. Now it’s almost flush. I will need two original valves. I accidentally hit another valve and it is bent. On the valve it says DB and has three holes on top for lapping. 
 

I don’t want to drill it out. With the valve in the way I can not remove the spring. Prying does not work it only bends the stem. I have been spraying atf and acetone daily   

[cutdown]

Hmmm. Time for an expert. You could try soaking it in the best penetrating fluid ever made. Its probably not obtainable or maybe never invented yet.  Next, you could try oxy acetylene, and heat the shit out of it. Might work.

 

See if you can fit the spring again in order to un adjust the cam follower adjuster. Thus may allow you to remove the camshaft, then drop the cam follower down [ after you have removed the burrs at its top edge ]. This will save you from ruining the camshaft.

 

If all else fails, remove the engine and give it to someone who can machine it out for you on their industrial drill press.

 

We once had a jap car in our workshop were the cylinder head had corroded onto the cylinder head studs. Even chain-blocking the cylinder head up in the air for a few days  with the cars front  wheels off the ground, we could not budge it.  We threw that engine away and fitted a replacement.

 

You have a problem there mate.

 

Best of luck.

[edinmass]

Use an induction heater to get the stem red hot. It will release. Are the guides bronze or cast iron?

[Mark Gregush]

Myers http://myersearlydodge.com/   ROMAR https://romardb.com/   sell new valves.

[Mpgp1999]

No dice 

[Mpgp1999]

This valve is quite stuck. Should I cut it then punch it through?

[DB26]

Is this the donor car you’re using to repair the wrecked DB? 

[Mpgp1999]

29 minutes ago, DB26 said:

Is this the donor car you’re using to repair the wrecked DB? 

That was the original intent but this car is very original. I’m going to drive it as is until the other one is up and running. I decided that I’m going to do an off frame restoration on the wrecked one and have this one as an original runner. I got the motor to run on one cylinder, but three valves were stuck open and now one valve is broken and very stuck.

[Mattml430]

I can’t see that engine running anytime soon the water galleries look to be completely clogged. Remove the exhaust manifold so you get good access to it. Good luck. 

[Mpgp1999]

Any ideas on how to remove the rust from a water jacket? I was thinking about filling it with water and flushing it.

[cutdown]

That propane or butane flame is not hot enough. That's why I suggested oxy acetylene. Best of luck. You may have to dig the crud out of the water jacket.

[Minibago]

I spent many days on my block with a pressure hose and various tools to pry loose the build up of rust and scale in the water galleries. The important thing is to get clear passage between each cylinder from top to bottom. It takes much patience and persistence to achieve good results.

[Mpgp1999]

[Mpgp1999]

I cut the valve at the bottom. Removed the spring. Engine spins freely. Valve still stuck 

[Mpgp1999]

Should I tap and drill the valve. If I can get a bolt head on the stem it could be helpful. 

[Mark Gregush]

The bottom of that valve looks mushroomed out. if it is, best get in there with a small file and clean it up before trying to push it up. I had to do this same thing with a Model T block, just kept working at it. Only took a chunk out of one valve guide boss. 

 

[Mpgp1999]

7 minutes ago, Mark Gregush said:

The bottom of that valve looks mushroomed out. if it is, best get in there with a small file and clean it up before trying to push it up. I had to do this same thing with a Model T block, just kept working at it. Only took a chunk out of one valve guide boss. 

 

I tried to get it to turn with a pair of vice grips. I tried to cut above the marks. I’ll file it.  Is there a way to press the valve up. 

[Mark Gregush]

Tap it up from the bottom, tap it down from the top, use plenty of penetrating oil then let it soak (not WD-40), tap it down from the top, tap it up from the bottom, rinse and repeat. Tap don't hammer and use a brass punch if you can. 

[Minibago]

I would clean the valve stem up at the top.

Obtain a thick piece steel to make a plate / block with a threaded hole for a high tensile bolt (perhaps larger than half inch and turn down the end to the diameter of the valve stem) I would clamp this plate to the block rather than use the head studs.

Use the bolt tightening to press out the damaged valve.

Trying to punch it out will not be successful as the block will flex and could break. If necessary you could take both the guide and the valve remains out together but this would require an hydraulic press.

[Mpgp1999]

1 hour ago, Minibago said:

I would clean the valve stem up at the top.

Obtain a thick piece steel to make a plate / block with a threaded hole for a high tensile bolt (perhaps larger than half inch and turn down the end to the diameter of the valve stem) I would clamp this plate to the block rather than use the head studs.

Use the bolt tightening to press out the damaged valve.

Trying to punch it out will not be successful as the block will flex and could break. If necessary you could take both the guide and the valve remains out together but this would require an hydraulic press.

If the valve guide is damaged how can I replace it. Is it threaded!?  

[Mattml430]

If you have access to a welder, weld a slide hammer to the top and try removing it that way. 

[Minibago]

I would suggest using a K Line valve guide liner.

 

 

 

New guides are available but this will require heating the block and using a press with the possibility of block damage.

[Mpgp1999]

4 hours ago, Minibago said:

I would suggest using a K Line valve guide liner.

 

 

 

New guides are available but this will require heating the block and using a press with the possibility of block damage.

I will try to use the valve guide. If the new valve is too loose I can knurl the stem. 

[Mark Gregush]

The guides are a press fit, pushed in and out from the top. How to do it is in the "Mechanics' Instruction Manual", but the valve would either need to be cut back flush with top of the guide or removed. 

With all the pounding you have been doing to remove the old valve, the guide may have moved. 

The top of the valve guide should be 1-7/16 inch below the top of the block, this is important, per the instructions in the MIM.

To get the old guide out, it needs to be moved down within 1/4 inch of the lifter, scored around the upper edge with a chisel then broken off with a brass drift. Then pressed down the rest of the way. Need to be careful so as not to crack the block.

With the valve cut/ground back top and bottom, there may be room to come down without having to breaking it by removing the lifter assembly. I don't know, have not tried. 

With all the grinding and cutting that have been done, you will need to give it a good clean up to remove all the metal bits.

 

Edited February 1, 2023 by Mark Gregush (see edit history)

[Mpgp1999]

[Mpgp1999]

I was able to tap the valve down and use a pry bar to move it up a little. After doing this twice I got very hopeful but it is still stuck. I got the bottom of the valve stem to clear the valve guide by a 16th of an inch or so. I’m not sure what is the best next step. I could either continue tapping it down and cut off the excess at the bottom.  Or I could try to push the valve up from the bottom using a bolt or something.  I could try to drill out the valve entirely, but I would need a stronger drill bit or I could use a carbide and grind it away.  

[JACK M]

Looks to be pretty well mushroomed at the top to be trying to drive it down.

The pushing up idea may work if its not similarly distorted on the bottom.

Maybe tap it back down until you can see it and clean it up a bit with a file?

How about then welding a nut or the likes to the stem on top so that you have something to pry on to pull it up?

[Mpgp1999]

If all else fails I’ll break out the welder. 

[Grimy]

Is there enough stem above the surface of the block to use a stud remover to get some rotational movement out of the stem?

[Mpgp1999]

There is nothing above the block. 

[Mpgp1999]

I taped the valve stem and put a nut with jb weld on it. I didn’t hold at all. Perhaps there was some oil or it has been cold and needed longer to cure. 

[DB26]

What a saga this has turned into! I hope it budges soon. 

[Ron Lawson]

If you can get a nut to fit why use JB I would have mig or stick welded it to the stem