I have some Fel-Pro MLS head gaskets for the Lincoln LS 3.9 and they do NOT fit the Jaguar 4.0/4.2 engines. (been-there-done-that)

Some parts fit and others are a no-go. The engines are SIMILAR but not the same.

bob

 

Thanks for the info. I believe you but I will still check to see the difference for my own curiosity.If and when those don't work I have a set in my shop for a 2001 xjr and I believe those should work, or should I get a set specifically for the 4.2.

Thanks

 

The Ford 3.9 V8 has a different 'curve' in the gasket/engine at the front timing chain area. That was the only difference I could see.

bob

 

No wisdom here, but is sounds at first like the original block suffered an untimely demise and was swapped out with this newer 4.2 block, but that somehow the original cylinder head was kept. Just a stab at keeping the cost down, I suppose.

Which sort of begs the question: Why would a car need 2 blocks replaced? Is there an underlying oiling problem, or a prior owner not believing in oil altogether? Just a thought. In any case, best of luck.

 

The reason for using 4.2 head gaskets is that they are multi layer steel and not subject to failure like the 4.0 sandwich.

 

Bob & RJ, the main difference I noticed was that the opening for the coolant passages was quite a bit smaller on the Lincoln LS 3.9. If I were to use these headgaskets I would risk overheating, and I sure in the hell don't want that. I will be placing an order for MLS Jaguar headgaskets.

Fmertz, please check my origional post on this thread. You will see photos of the damage caused by tensioner failure. The reason I opened up the bottom end was to replace the piston that was damaged. While I was doing this I was also going to replace the rod bearing. It looked in excellent condition but I don't want to take the chance of a flat spot being created by the pressure on the bearing from the valve to piston contact. As mention earlier I discovered that at least the block if not the entire engine is a 4.2. The head scratcher is why are there plastic bodied tensioners on this engine. 4.2 should be steel bodied, if I'm not mistaken, or what dumb**s would put plastic bodied tensioners back on if they changed the heads.


I'm trying to figure out if this was a complete engine exchange or just a block exchange. Also if the gasket kits I purchased, I bought a kit for a MY2000 because that is what I thought I had, are going to work on this 4.2.

I really appreciate all of you responses so I can get this car on the road again.

Thank You All

 

Researching I think was I have is a 4.2L block only. Looking at photos of a 4.2 the timing chain cover doesn't have the casting for the VVT from the AJ26. The intake manifold gasket is one piece on the 4.2 where the 4.0 has the odd shaped orings. Also the valve ,cam, covers are different along with the thermostat housing.

So it looks like to me the brain surgeons that put this motor together did all this work and put the old timing tensioners and guides, they are cracked also, back on their rebuild.

Well their stupidity let me get this car for $850. I'll put about a $1000 in it to get back on the road and have another cool looking XK8 convertible on the road again.

 

Well since I'm waiting for parts I thought I would clean all of my parts for reassembly. Got that all done so I started working on the heads.

Started with the head from the XJ8 with the bad rod that is going to replace the damaged head. First I remove what I call the cam buckets. Most came out with no problems. But the #3 bucket on the intake side would not come out. I tried putting oil on it then WD-40 and it still wouldn't budge. Reluctantly I had to use pliers to get it out and it still took about 10 minutes to get it out.

In the photos below you will see inside the head where the bucket was removed. The material you see is material from the disintegrated rod bearing. That is was what was binding the cam bucket. The other photo is the bucket itself.

Material also got into the cam shaft journals and I'm going to need to resurface those too. It will probably take me a week to repair the head but what the hell I'll have something nice when I get done.

 

It's not uncommon to have a lifter bucket that's fighting to come out. I have a very strong magnet that's bought just for that very reason. It's even more difficult to get the shim out of the bucket. Have fun adjusting those valves. PITFA!

 

Apparently, magnets are not recommended- pressurized air is supposed to be used to blow the shims out. Strange, but it works! I have done both ways myself.

 

Addicted2boost, l do use a magnet to remove the buckets from the head and they all came out fairly easily. But the bucket in question was almost froze in the head. What was binding it was the bearing material that was in the oil and reduced the clearance that it caused it to bind.

Dsnyder, Glad to hear that a little air will remove the shims.

Today the Jag dealer calls me and says my parts are in. I was exchanging the 4.0L rod bearings, NCC1612BA4, for the 4.2L rod bearings, AJ83904. The parts man decided to see the differences between the bearings. They were the same bearings. The numbers on the back of the bearings were the same, the 4.2 bearings should have been shorter. The strange thing is I order the rod bolts for the 4.2 and they were shorter like they should be.

So I called SNG BARRATT to see if their bearings for the 4.0 & 4.2 are different sizes. They had none in stock so he is going to contact Jaguar to make sure I get the correct part this time. A lot of time for $25 in bearings.

Addicted2boost I will be happy when I'm adjusting the valve clearances because I'll almost be done by then.

Anybody else have this problem?

 

I have seen a few heads with the lifter bucket oil feed holes were clogged with coked up oil and ending with the same results. Unless you have a large amount of bucket shims, it won't be that easy to adjust the valves. I've spent countless hours trying to get mine just right when I had the heads off.

 

I have 2 bad motors, 4 heads of shims. I see what you mean by it being difficult to get the shims off the bucket. I started removing them from the bad motors to give me an invetory of shims for when I do the adjusting. Even with air they are a PITA. When I built 1300cc motors for my sons race car Yamaha has a grove on the bucket so you can remove the shims easily even with the camshaft still installed.

As for adjustment if you don't have a shim that is the right size you can do the calculation to see how much less shim thickness you need, usally less because of wear if not put in a larger shim, and with a dial indicator measure the height of your valve and little by little grind the top of the valve till you get the desired height. It is usally a very small amount but you can get the exact clearance that way.

 

I never got a response from sng about the rod bearings. I then contacted Jaguar Palm Beach. I explained my situation that I need bearings for a 4.2L. They had none in stock but got them front England and they arrive a couple of days ago. They were the correct ones. I'm back in business.

While waiting for the bearings I rebuilt the heads and they are ready to be reinstalled. I'm just short a few shims and I'm sourcing those from another member. Just hope he has the ones I need.

Have a day off work today so I'm going to try to get the piston and rod back in and get the bottom end buttoned up.

 

Finally got all of the correct parts and finally started it last night. Reminder I bought this car with a motor that was froze, so I don't know how it ran the last time it was running. So the issues might be from before I got the car or I may have done something wrong. It was hard to start and couldn't get it to stay running for more than a few seconds.

Checked around and found a vacuum line underneath the throttle body was disconnected. Discovered it was missing a clip, thanks to jagrepair.com, that kept it in place. Purchased that today and installed vacuum line.

Started it back up and it kept running now but only at idle aND still running rough. Give it any throttle and it dies. I let it idle long enough to bring it up to opeating temperature. Now it's giving me codes.

At first it gave me P0300, P0301, P0302, P0303, P0304, and P0341. Showing random misfires on bank 1 and CPS problems. I changed the CPS I got from one of my donor cars. Also checked the two wires from bank 1 CPS connector to the ECM. The two wires had no resistance.

Put everything back together and now I get these codes P0300, P0302, P0303, P0308, P1316, P0340, andP0341. The misfired cylinders have moved. It is still running rough at idle and can't give it any throttle.

Before every restart I do a hard reset. And last night it blew the 10amp #18 ignition coil supply fuse as it was dieing or it caused it to die.

Hope somebody can chime in, I'm just now starting to learn about all these modules and sensors. I'm used to my 66 Mustang that has two wires going to a single coil.

 

I been trying to dianose the running rough problem, diicribed in previous post. Since it blew the ignition coil fuse I was looking in the direction of electrical. But first I put a new fuel filter on, probably need one anyway, and checked fuel pressure at the Schrader valve. Got 40psi so I figure fuel is good. And while it was running I took a stethoscope and could hear each injector clicking.

Next while the car was running I pulled the coil wires of coil #1. There was no difference in the sound of the motor. So I figured that I found the problem and checked each wire from all of the coils to the ECM figuring I had a short somewhere. What I should of done first was to pull the coil and spark plug to see if it was firing. So after checking every wire from the coil to the ECM they all checked out with no resistance.

So now I think it is the ECM. I took it out and open it up to see if there was any evidence of any problems. Everything looked good but that doesn't mean there still might be a problem with it.

So I get suggestions from dsnyder and my son to check the compression. I'm saying to myself it can't be a compression issue I put on a new headgasket and I reseated the valves. I take the spark plugs, out, they are new, to do the compression test. On the left bank the plugs are completely fouled, the left bank has a head is from another car because the origional was damaged. On the right bank the plugs look as if they were new.

It doesn't take Surlock Homes to figure something isn't right. I do the compression test and I get between 175 to 185 on the left bank. I check the right bank and they are all 0.

I pull the head figuring that I must of damaged the headgasket or maybe something got between the head and block when I did the installation. The headgasket looks undamaged.

Since water from the head got into the cylinders from the head removal I topped them off figuring if it was a problem with the pistons that water would drain around the pistons into the crankcase. No drainage the pistons and rings look good.
Take the head to my bench and remove the cam buckets. Put spark plugs back in and turn the head over. Pour solvent into each cylinder to see if the valves are leaking. Only a slight leak on one intake valve and I will seat that one better later.

Only one thing I can think of left. I take a piece it straight flat iron and put it across the cylinders. In the photo below you can see the gap. I have a flashlight behind it to show the gap easier. I measure it with a feeler gague and there is about .007" gap. I have a warped head.

My mistake I should of checked it before I put it back on but I assumed, you know what they say when you assume anything, since it was the origional head there should no problem.

I checked the block and it is good and flat. So now I will have the head surfaced this week.

 

It's a good thing you have determination and patience! Keep it up and you'll get it. Adjusting those valves are fun aren't they?? I did mine 6 months ago on my 234K mile XJR when I had the heads off. PITA!

 

Monday I got the head back after they shaved .007" off. Picked up new headgasket from dealer and proceeded to put things back together. Before putting the head back on I insalled the spark plugs aND turned the head over and poured solvent inot each cylinder. Not a single valve leaked.

Put the head back on the car with new headgasket. Torqued the new head bolts to specs. Installed cams and timing chains. Timed the cams usING the proper lock down tools. After I get it timed I remove the timing tools and rotate the engine a couple of times with a socket on the crankshaft and then double check the timing by making sure the flats on the cams were aligned. Everything is perfect.

I decided I was going to do a compression check before I put everything back together. I get a reading of 0 on cylinder 1. I then check them all and they are all 0. I think what the hell, actually I thought a different word but we have ladies on the forum also, what is going on. It's acting as it's out of time but it can't be I double checked the timing and the valves weren't hitting the pistons, the motor turned freely. I put my finger over the spark plug hole and it about sucked my finger in. I was getting vacuum not compression.

So i'm staring at the head trying to think of what could possibly be causing this. I'm looking at the intake cam and I see the factory part number on it and think to myself I didn't put the wrong set of cams on the head. I checked the numbers and yes I did I grabbed the wrong set of cams off the shelf. I grabbed the cams that came from the donor left bank head. I had left bank cams on the right bank. So the right bank was 180° out of time. I don't know how the engine even ran on four cylinders.

I take a lot of time when I disassemble a head to mark each valve, cam buckets , and springs to make sure everything goes back to the same spot it came from. I never mraked the cams, I just put them in a tray so they won't get damaged. I learned my lesson, from no on I mark the cams as to what vehicle and what bank they came from.

You all have permission to have a laugh out loud on my account.

I'm thinking about starting a new thread in the " Off Topic" section called the most stupid thing I've done.

 

Easy mistake, and I'm guilty of not labeling everything, but I will learn from this.

 

If that's in your top 5 then I'm way ahead of you....or behind your. BTW, since this is a Jaguar forum, any ladies would be well acquainted with all those words.