I'm tearing down an friends engine to rebuild it for him. Back story is was rebuilt, and in theory properly machined. Had this done while he was away in college in Kansas, USA 3 years ago, now the car is on the west coast of Canada. Engine has 500 miles on it since it was rebuilt and when I pulled the dipstick, it looked like silver paint the oil was so full of metal flakes. So engine came out and the head was replaced (that was the source of the metal) and I was asked to assemble the engine. Lower end was together and I decided to take everything apart to double check clearances etc and clean completely.

This is the condition of the rear main seal - can I have the collective opinion about it's condition please and my options? Replace, resize, or leave well enough alone and reuse? as far as I know, it wasn't leaking. Alas, I don't have the proper sizing tool available.

The rope looks burnt to me, thus my asking.

 

Not sized with the proper tool and burned! Replace and use the proper tool to size the replacement. That one looks like the problem engines of the last XJ6 cars.

 

Agree with CF

Machine the scroll off the shaft (to 3" IIRC) & fit the SKF Viton "flex-seal" from Rob Beere.

There is a thread here on the subject.

 

While that would be nice, there isn't either the budget or a competent machine shop around here to do that work. I'll fit a new original style seal to it once I've cleaned everything.

 

Understood JB!

 

This crank has been ground to 0.040" undersized and from all the metal that went through it I can feel the grooves on the journals with my fingernail. If it was my engine, I'd replace the crank and rods, so wouldn't be doing the seal conversion on this crank.
Some nasty looking bearings for having less than 500 miles on them.

 

Yugh!

 

Wow. Those bearings are munched. If the crank is already 40 under, you have no choice but to replace the crank, right? I think 40 under is the largest bearing you can get and that crank clearly needs to have material removed. It is a boat anchor in my opinion (or maybe an interesting lamp base).
I just went through the anxiety of installing the rope seal in my engine. I have to admit that I don't understand what the sizing tool is doing. The rope seal is as far into the groove as it is going to go. I don't see how it can compress any more. In your picture above it appears to be driven as far into the groove as it will go and it is still mushroomed over. I used the crank itself (end cap torqued down) to push the rope seal into place and then cut the ends with just a tiny amount of seal proud of the surface in the hopes that the slight interference fit will help the seal. I can feel that the newly installed crank seal is adding some drag. Is that to be expected?

 

Bloody hell! I have seen some botched jobs in my time but nothing quite as bad as this.
I suspect that the engine was assembled "dry" and without some initial lubrication the crank and bearing are going to grind each other to death.
I did see a case of a MK2 engine overhaul where the crankshaft oil galleries were blocked with debris which the engine reconditioner had not cleaned out and similar damage resulted. This led to a law suite.
I endorse the previous remarks on this post that this crankshaft is a write-off.

 

Another shop rebuilt the engine and they stripped cam studs, the cam oil feed pipes were overtightened and the threads stripped out etc. It was a mess, and that's what lead to the head being replaced. The shop in Kansas resleeved the block with new liners and I'm wondering if the block wasn't properly cleaned afterwards. This is the filter behind the lower timing chain tensioner.

Agree, keeping the current crank wouldn't be my first choice. I've told the owner to keep an eye open for a replacement crank and rod set. Somewhat surprisingly, this engine had excellent oil pressure.

The owner is 25 and this was his great-grandfathers car that he inherited. Alas, funds are tight for him at the moment. I'm helping him assemble the car so it can at least be driven again.

 

You are a kind soul JB. I realise you are doing it to help a young man that is obviously sentimental about the vehicle.

What a mess & the very best of luck. This one has "botch job" written all over it. I hope you find no more evil doings in that motor. I would check everything.

 

Much of the body of my Mk2 was restored by people who went to the same school as these engine men.

 

The good thing is the ring gaps were perfect, the piston to bore clearances were perfect, and the rod and main bearing clearances were in specification, so that's a start! Oil pump has a few marks, but it will be servicable. I've seen worse.

 

Well that's some good news!
G

 

To close the loop, I have the engine back together and delivered to the owners house.

It needed very thorough cleaning, I was amazed at the amount of metal particles than came out in my parts washer. I ended up replacing the timing chain assembly due to wear on the sprockets and the backing plate due to the metal particles. I also used one of the thick Cometic MLS gaskets to bring the compression ratio back to 9:1

I did make a sizing tool for the rear crank seal, even with the tool it takes a fair bit of effort to get the ropes into the grooves deep enough. I used the black ropes, not the white asbestos ones. I also soaked them in oil for a few days prior to installation to help the process. The crank turns by hand, so I hope it's right. I'll find out soon enough I guess.

 

I wish you well. I use a wooden hammer handle to do all the initial rolling of the seal into the grove & then the sizing tool. One should NEVER trim any protruding ends off of the seal or it will leak. You need to roll the entire seal until flush & then use the sizing tool.

 

I ended up using a piece of steel rod I had to initially work the seals in, and then the tool for the final sizing. I did know about trimming and just kept working at it until I had all the length pressed in. I did put a small dab of RTV on the faces of the metal seal retainer halves where they came together. The rolling in took more work than I thought!

 

Thats fine. Mine does not leak but maybe I will put a dab of Yamabond on the ends next time. Belt & bracers.

It is time consuming to do correctly. In fact a PIA.

 

All that "silver paint" in the engine oil was the bearing metal from the main and big-end bearings.
Apropos the rear seal, it is essential that the crank can be turned reasonably easily after fitting the seal. If the seal is too tight, the heat of running can be such that it melts the bearing metal in the rear main bearing that lies close to the seal. This then results in loss of oil pressure and engine failure. I also hope you managed to clean out the dirt traps in the crankshaft. It is a bit of a PITA to do. It would have been better if these had never been in the crankshaft at all, but there you are, all XK engine users are stuck with them now !

 

The metal came from some of the bearings, but also from the head. The shop that previously rebuilt the engine butchered the head, there was stripped threads everywhere and the tappet buckets and guides had major wear. How they were able to mess things up so badly, I'm not sure. Maybe their only assembly tools was a sledge hammer and 36" pipe wrench?

I took both the block and crank to the car wash and cleaned everything with the engine degreaser first and then the 2000psi soap. I wore a raincoat and safety glasses and I still got wet, but everything came out nice and clean. I put the spray nozzle right against each drilling in the crank journals and got a large stream out the other holes. I had previously sprayed brake clean through everything, that's great stuff for loosening deposits.

But yes, the rear main seal is a PIA.