Xk150 harmonic balancer removal

I am pulling the engine in a xk150 to do a transmission swap. I was advised that the harmonic balancer needs to be removerd before pulling the engine. Ive already removed the drive shaft. Does it need to be reinstalled to help lock the motor before the center bolt can be removed?

You could use the output flange on the tranny to “block” rotation, or use an air wrench on balancer bolt, or use a big screw driver thru the flywheel viewing port (in bell housing) to lock the F/W, or use a long length of threaded rod to act as a piston stop…

I was not aware that the damper had to be removed on a 150 to pull the engine. It does not on a 120. Maybe this advice came from an E-Type owner, which would be correct for his car.
If true, another idea is to remove the trans top cover and put it in two gears at once, say 1st and reverse.

It helps but not essential. as suggested it should come free if you use a shock/impact driver approach. even a decent hammer on a 15/16 spanner will work. A for of people cut the bonnet support/closing frame to give more access ten simply weld it back in. (makes it like the 120)

Thanks , I made a bat that bolts to the flange and locks against the tunnel. Would have been much easier to gave done it before removing the drive shaft.

Hello Pat. I’m going to be pulling my 150 motor as well for a transmission swap. I’m going from auto to 4 speed. Are you keeping original type or converting?

I swapped to a T5 . I got a kit from Driven Man that includes the trans, If you go that route you have a .63 or a .73 adapter plate, speed cable and a new drive shaft. Its quite a job to get everything out and then back in. I’ve got the original 4 speed with overdrive the drive shaft and all the hardware if you are interested. That includes the speedo drive cable, shifter, w/ knob and the clutch disc. I could even include the OD switch and indicator dash plate. The two switches on the gearbox, one for activating the over drive one to lock it out on 1st thru 3rd are there but the lock out switch is stuck closed. Which doesn’t really matter but should be replaced.

I had a couple of issues with the T5 conversion kit, the bolts that hold the tranny to bell housing were a ½” too short and the speedo cable is 16” too long. I told the supplier about the bolt issue I have not informed them of the cable issue. There are several items that need to be removed from the engine to pull it. The motor mounts are a challenge in the back. The right side is particularly difficult. Cutting off a box end wrench helps a lot. There are two ground straps. Easy to miss one. The interior has to come out. Removing both floor boards and the tunnel are required. The clutch slave cylinder needs to come off as does the timing pointer at the front of the engine or it will get damaged trying to get the engine out. The harmonic balancer needs to come off, Orielly auto parts will loan you a puller for free. I took the tach drive off the engine to keep it from being damaged and I found using wire maker numbers to label everything made reassembly a breeze. You also need an adjustable engine hoist so you can shift the balance point. Harbor freight has them for about $40.00 and the four L brackets fit the head bolts. I found using the back head bolts and the third from the front helped the angle. You need three people to get the engine and transmission out . take the front tires off and drop the spindles down on blocks and put jack stands under the rear frame area. It really helps. The original setup is tight to get out. The T5 is about 1 “ shorter . I had the exhaust manifold silver powder coated while I had it apart. It looks great. Take a lot of pictures, you will be surprised what you might miss when it goes back together. If you have any questions or need morale support give me a call. 214-697-5828 . Much of this information was generously shared by two brothers, They are very talented Jag mechanics that specialize in old vintage jags and were very patient with me.

Good luck and take your time. I’m guessing it’s a 60-70 hour job if you are a fairly good mechanic ( a shop quoted me 30 hrs but I don’t think that’s realistic ). Btw the T5 has a 1-1/16” dia input shaft, the original tranny has a 1-1/8” dia. Also buy some moving blankets at Harbor freight or Northern tool. They help protect the fenders and interior as well as the windshield. Blue painters tape will help protect things as well.

Hello Pat,
Thanks so much for all of the useful information. I’m still wrestling with converting to standard or re-sealing the automatic back up again. Out of curiosity, how much would you want for all the kit you have?

I may take you up on the phone call when the motor is hung up half way out and won’t go back in!


I’m open to suggestions and not in a hurry. Probably about $2000.00. The t5 kit is around 4800 . You still need the bell housing, clutch pedal Assyrian, slave cylinder and bracket . You also will have the tunnel modification . It’s a lot of work but well worth it if you enjoy driving the car.

Call me if you want to talk about it. Text me before hand so I know it’s you.

What modification does the tunnel need besides the hole for the stick?

There is a sheet metal “dome” that goes over the top of the hole in the tunnel. If you think you are going to do the modification I can try and make a simple template of the tunnel hole and a rough sketch of the dome piece,=, Mine are still off so I think it would be a faily easy to do . Maybe use some heavy paper and trace it out. I’m probably a week or two away from putting it back together so the timing is good right now. Let me know … The shifter needs some clearance for the lever movement. I have some foam board I could make a profile of the dome so you could make a replica from it. The hole in your tunnel may be the same but it would be good to know before you start., The stock transmission and the T5 are supposed to be configured the same.

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Here is a picture of a T5 next to a Moss 4sp with O/D.
the gear shifter of the T5 fits exactly where the Moss was.

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Thanks for the picture. I’ve got it in and everything works. The T% kit came with bold that were ½” too short and the speed o cable was too long. I was lucky enough to have a friend that’s a master machinist and when we shortened the cable the fitting got damaged. He made another one out of stainless . I drove it briefly last night, now all I need to do is put the tunnel, floors and interior back in and I’m good to go. I now have a spare Moss box if anyone needs one along with the drive shaft and cable. The car is going to be much easier in traffic with the new ratio. This project has gone really well.

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I have been driving mine for two years now and the T5 has brought the car alive, it was a joy to drive before now its awesome, and being able to ram into first while still moving is magic. I had to play with the speedo drives and ended up with the brown coloured driver, you can get a packet of 6 drives with various teeth to get your speedo to be correct very cheap on e bay. I also had to increase my clutch actuating rod by one inch as l did not have enough adjustment.

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Hello Pat!
Good to hear you got it in and working. I sent a quote request to Driven Man. If you could photograph the dome and tunnel I think that may be good. I don’t want you to have to do a whole template but appreciate the offer!

No problem. Here is a list of things I think you will need in addition to the driven man kit. A bell housing with the throw out bearing and slave cylinder assembly. A master clutch cylinder with the pedal brackets and linkage. I’m not sure who will have the parts . Recently , I started buying parts from Engle Imports in Kalamazoo MI. They know old Jags and have great customer serv ice. I deal with Buzz 800-900-2905. They may be able to help you find the other parts you will need. The forum is also a good place to start.

I’ll put a tape measure on the tunnel when I take the photos so you can check your setup to compare. Plan on taking both floor boards out . It makes things much easier. Also ask driven man if they can shorten the speedo cable. Mine was 16” too long and I am fortunate that a friend could modify it, otherwise there would have been a big loop that was cumbersome. Your original cable will not work. I also went with the .73 final drive ration on 5th gear . >63 was too low for crushing speed, IMO. The Moss box was .8 in OD. BTW, where are you located?

Thanks for the info!

I’m not sure what the rear end is with an auto to determine what ratios to get. I’ll have to do some digging…

I’m in Red Hook, NY - Hudson Valley - not Brooklyn.