Greetings!

As I have been working on the XKR, one of the tasks was to pull the oil pan to see if there was any indication of bottom end issues, as hinted by the PO's mechanic. His belief that the valves had kissed the pistons, and in the absence of any evidence of that, had me questioning his comments that the bottom end needed work too.

Looks like he may be correct:



Some of the pieces that were in the oil pan look to be possible bearing shell, but others are too heavy for that, with the biggest piece in the picture having what appears to be black paint on it. (rear seal shell?) Oh well, looks like I pull the engine after all.

Has anyone been able to pull the engine out without the transmission? The heads are off, so it is possible to get to the top trans bolts.

All advice is welcome.

Thanks in advance.

TC

 

From your first post .................

I pulled the drivers side head today, and again, no direct evidence of valves into pistons, but have yet to disassemble either head to check for sure for bent ones. One interesting find once the drivers side head came off was an entire bicycle inner tube crammed down the plug hole!! The mechanic told my the previous owner's friend had tried to effect some sort of repair found on the net. What that was to accomplish, I have no idea.

I think you just found the rest of the bicycle in the sump

 

I had these in my oil pump screen (coins are for size comparison) From the block being drilled at the factory was the consensus. It might be more common than we think.

 

Hi TC Johnson The rubber inner tube is probably a version of the old rope trick. The trick being bring the piston down about halfway and feed some rope into the plughole. Turn engine to TDC. This jams the valves enabling the springs to be removed to change the stem seal. Probably will not work with hydraulic valves. The metal in your engine looks like drill swarf!! Probably too big to get into oil gallerys, but not good!!

 

If you notice, I included a ruler to show how big these pieces are, which you can see if you expand the picture. There is still one piece caught in the windage tray that I could see from below. Waaay too big for machining scrap. At one point today, I thought there may have been something at the front of the engine that somehow fell into the pan, but am at a loss what the bigger chunks could be.

A bearing shell would have to have worked its way out of a rod and been chewed up by the crank, but I have never heard of that happening without the rod itself grenading. The pieces are also magnetic, perhaps ruling our machining scrap from the aluminum block.

Still hoping I can yank the engine without the need to pull the tranny. Gotta have a dream.

TC

 

What about parts from your tensioners the top rails being chewed up by the chain?

 

No go on the tensioners, since they were first gen plastic. It looks like the tale will be told on tear down. Although poring over all the diagrams has not shown any part that seems a likely suspect.

My question still hangs out there about pulling the engine and leaving the transmission in place. It is a space issue for me to stash the trans while working on the engine. I only have one half of a double garage, and not much storage space around the stall.

Thanks for all the good comments.

TC

 

I have seen pictures of the engine compartment with the transmission still in place, but I'm sure some one on the forum must have the answer.

 

Guy's,
I have seen many engine tear downs in my life time--longgggg time----but I have never seen anything like that, without complete engine distruction. Rod end bearing inserts, main bearings, broken rods, busted pistons, what ever.
Please let us know from where it came. How about you H20boy, where or what was the cause of your find?

Chuck
XK8

 

Moderator,

How do you get rid of these little Smilies?????

Chuck
XK8 vert

 

Having been a machinist, I think that debris is metal shavings from lathing, not drilling. I cannot think of any engine function that could produce this. More than likely not from the engine build unless the engine was sabotaged. My first thought was a guy dumping debris in the engine for some reason.

 

I never found the true cause of my shavings, but that oil screen sure saved the engine. I'm glad I dropped the pan for a look see...it only cost me a little extra time during an oil change and a new gasket.

 

I have been looking at all the engine diagrams in jagrepair.com, and trying to see what it could possibly be. I flattened out some of the pieces, which are all ferrous, so not aluminum, or cast steel or iron like everything that would be in the crankcase. One item that got my attention in the diagrams is the oil cooler diverted valve. It comes out today to see if something broke loose.

This car has about 90k on it, original tensioners, and no indication of damage on the piston tops or the heads. Too thin and the wrong metal to even be bearing shell. Truly mystery metal.

TC

 

Well the mystery has been solved. That is the only good news.

On complete dis-assembly of the engine, it turns out the shavings in the pan were from not one but FOUR spun rod bearings. I am shocked that the engine didn't completely grenade with multiple rods through the block! In fact, it would actually turn over with a good sized breaker bar.

I plan to add some pictures of the remains. The crank is toast, and probably four rods will need to be replaced, as I would never trust a resize or repair after this. Main bearings looked good, but that is academic, since the rod journals were trashed.

The block actually looks pretty good for a Nikasil, with no sign of damage to the cylinder walls, and you can still see crosshatch with a flashlight.

My next step is to decide if I look for a crank and the piston sets to do the rebuild, or go for a reman shortblock. I have already refurbished the heads, so i would only need the shortblock.

Anyone with a line on sources for a crank, other than used stuff on eBay?

More to come.

TC

 

As I said above, "I've seen many--------unless it was rod end or main bearings".

You've answered my question with the discovery that it was in fact rod bearings. That said, you may end up with a good engine by just replacing what's bad, but I think you will be way ahead----money not a problem-----by going with a short block. You already have good heads and with a short block, you'll end up with a basically new engine. IMHO.
Thanks for the results report and good luck. Let us know your final decision and end results.

Chuck
05/XK8

 

I needed to have an engine swap last year. At least two bearings had spun and the crank was galled beyond recovery. As in your story, it was amazing that the engine was running at all, let alone as unbelievably smooth as it was. BUT WHAT A RACKET IT WAS MAKING!!!

 

I'm wondering what caused the bearings to go bad

 

Should be gone with your next post Chuck.

 

Possible oil starvation?

Jaguar has increased the oil level specification at least once if not twice on the
V8's. Notably in 2000, so your 1998 might benefit. Your new MAX mark would
be the distance between MIN and MAX above your current MAX mark on your
standard issue dipstick for a 1998. People just put a nick in the right place
on the dipstick using a file.

They started issuing new dipsticks with different part numbers that had higher
level markings by a quart.

Then the Silverstone edition came along and they increased it again for that
one model. Stickier tires, more g-force, oil starvation in cornering.

Brutal detailed it in the silverstone thread. I alluded to it a few minutes ago:

https://www.jaguarforums.com/forum/x...change-130122/

There is also viscosity to consider. Jaguar's weasel words with regard to viscosity
are:

"we recommend 5W30 for best fuel economy"

Well best fuel economy has nothing to do with best engine protection.

Yet, some people slavishly point at "we recommend 5W30" while ignoring
"for best fuel economy" when responding to posts asking for oil advice.

 

Probably oil starvation, or a big time overheat. No indication of head gasket problems, but then again, I had only minimal contact with the PO. I located a used crankshaft at a good price, along with four rods and pistons from and XJ8. Crank number matches the trashed one, and measured out in spec, so I feel good about the score. I plan to have it magnafluxed just to be sure. Rods were also in spec, so I should be able to use standard bearings, based on my final measurements.

I am cleaning up the pistons, but am seeing imbedded "clag" (as David Hobbs would say) from the spun bearings on several of them, in spite of a good scrubbing with red scotchbrite. I have not had any luck so far in finding some pistons, other than at the HUGE price quoted by SNG Barratt.

One other thing. I thought I had a Nikasil block based on the age of the car (built in April 2000), but the cylinders seem to be magnetic, which could suggest the block has steel liners. Could that be?? Is there something in the Nikasil plating that would be ferrous?

If anyone has a line on a source for pistons, or a set of SC pistons lying around in reasonable shape, please let me know.

Thanks

TC