I am in the process of pulling the heads on my spare V12. The right side came off easily. I am using the head pullers from Jaguar Preserve (Camp Chaos). I have 2 sets.
The left side head comes up about 1/2 inch and stalls. I released the pullers and bolted the head back down to try and break the crud on the studs. I am using PB blaster to soak the studs. The studs on the exhaust side are free because the penetrant flows down the stud holes. On the intake side it is a different story. I have been using the penetrant for over a week and it is not going down the stud hole. Right now I have the head sitting at 1/2 inch off the block. My plan is to bolt it back down a second time to see if it will break through some more crud. The problem seems that as you raise the head the crud jams up the head. Just in case the question comes up... I am lifting the head evenly so it does not jam on the studs on one side. Any ideas as to how to approach this? PB Blaster is not doing the trick. What other penetrant can I use?

 

You need to use the single plate tool. It spreads the load over ALL of the studs. We have never had a member that failed to remove the heads and no stripped or broken studs. Best of luck.

 

I am a member of the JCNA. Or should I say JCOF. How do I go about getting the tool?

 

Here:
http://www.jcna.com/tool-loan

Jon

 

jal1234: I went to http://www.jcna.com/tool-loan and I can't find the cylinder head puller. I browsed through all of the tool catalogs and it is not listed there.
I also went to Coventry Foundation's website but when you click on their tool rental it sends you back to the JCNA tool site.
I may have to call my local Jaguar Club for more assistance.

 

There's a phone number on the How the Program Works web page. 888-258-2524 Ex#7. Call them.

Jon

 

OKAY all: I was able to remove the right side head intact. However, the side with the dropped valve seat, cyl #1 was stuck on solid. I could only get it to lift approx 1/2 inch. I had past the point of no return so I could not clamp the head back down. Given that the head is damaged, I decided to cut the offending studs one by one. With the puller still attached, counting from the front, I cut Stud #6, tried the puller and no go. I then cut stud #5 - no go. Cut stud #4 still no go. finally, I cut stud #3 and the head came off.
Now, I have to remove the cut studs. I have various stud removal tools, but I am soaking the bottom of the studs with a 50/50 mix of acetone and marvel mystery oil before I attempt to remove them.
Now that the heads are off, I am going to remove the timing chain cover to replace the chain and tensioner and all the gaskets on the oil pan and windage tray.
Given that I have to turn the engine to clean up the piston bores, what can I use to lock the liners in place before turning the engine. I read somewhere that I can use fender washers to hold the liners in place but it did not say where to bolt the fender washers on the block. The shortest stud is 3 1/2 inches long. While I am waiting on a response I will see what I can come up with.

 

Content / V12 Engine / Clamps for cylinder liners - S3 E-Type

This is the sort of thing. A few pieces of wood over the relevant studs and across the liners will do fine, too!

On stud removal, one of those magnetic resonance heating gizmos might be worth a try if the mixture does not work. Heat the stud really hot, let it cool and try again.

 

We have a lot of tools that are not on the PDF. Since the head puller is not a factory tool it is not included. We do need to update the PDF but as all ore volunteers there is limited resources. That said if you simply fill out the tool loan form and ask for V 12 head puller that will do the trick.

 

Now that the engine block I am going to use is partially stripped down, as stated before, I am going to replace the timing chain and tensioner and the necessary gaskets. Once the bottom end is out of the way, I am going to pull the engine from the car. Since that engine has bottom end issues, my plan is to pull those cylinder heads to use on the aforesaid block.
So I am still going to get the tool from JCNA. I am timing it so that I will have everything ready to pull the heads, so when I get it, it will be a 2-3 day turnaround. I should have the engine and tranny out of the car sometime next week.
This is what I came up with to hold the liner in place. The washer only covers one edge of the liner. These are on the 3/8 bolts on the block. Will that suffice if I take my time and turn the engine slowly?

Is this good enough? The washer is only covering one edge of the line

 

Another thing. With the heads off, I removed to timing chain cover. Even though I am replacing the chain and tensioner, I want to know if there is a way to get the tensioner in the install position. Right now the tensioner is in it fully curved position. I know that you have to move it upwards to get the rod to lock on the tab and that would put the tensioner in what I would call the install position. That would leave the chain with slack to install the camshaft sprockets after which you would have to release the tensioner against the chain.
Given that I have the old tensioner exposed and the heads off what tool is needed or what can I make to mimic the tool to to put the tensioner in the straight position.
I don't know it this is making any sense at all but I want to practice doing this.

 

Watch this video on the timing chain tensioner. He shows the pitfalls of the factory tool and a homemade tool that works better with less risk of breaking the tensioner in the process.
Jon

 

Thanks Jon. That video answered my query regarding the tensioner. I can make up a threaded tool like that but I will wait until I have the heads installed.
I looked at the cost of a new tensioner and the price blew my mind. My option is to try and save the existing tensioner. the engine in the car also has a tensioner so I would be careful not to break either of them. With the use of the threaded tool I will not have to retract the tensioner all the way and that in itself will prevent it from breaking.

 

The "homemade" tool is a reasonable copy of the JD42 which was replaced with JD50. Either tool worked well on the V12 when they were newish. At this age it will be a miracle if you can retract one of them without breaking or at least cracking them. New ones are $$$ but the job is too complex and the risk of a broken tensioner too great to not replace them. Best of luck.

 

Some good news: Yesterday I tried to remove the studs and they felt as if they would shear off further down. Today, I was able to extract the 4 studs I cut. I soaked the studs with a 50/50 mix of Acetone and Marvel mystery oil overnight.
For those who have never seen what destruction a dropped valve seat do I have attached a pic of what it looks like.
Strangely, there was no damage to the piston or the piston bore.

 

The Jaguar method of pulling up on the tensioner exerts a lot of force on the lower pivot pin bore.
There is a big risk of breaking that pivot point as shown in the Camp Chaos video.
An alternative is shown on page 6 of this Word doc.

 

I want to retract what I posted about no damage to the piston #1 where the valve seat dropped. I was cleaning out the cylinder bores and I noticed that there was some slight damage to the piston crown. There are a series of small dings to one side of the piston. I am not happy about it. I am thinking of changing it out with one from the engine in the car.

 

Yeah, I'd change it also. May have pinched the top ring land, or cracked the top of the piston. Change the liner with the piston, in case they are a different size group. Be sure to make sure the pistons weigh the same. It'll also give you a chance to check that rod bearing to ensure it didn't get damaged when the piston got damaged.
Jon