And here I was, thinkin’ it was YOU who wanted a more responsible thread.
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Removed the #3 Rod Cap. Pics below. I pulled the bolts also. The right side on this #3 Rod looks a bit funky, but I believe this is an original XK Series 1 rod bolt. By the way, there was and is a gasket under the oil pipe where it attaches to the block. The #3 Cylinder is the one I’ll remove the plug on. The bearing appears new, undamaged and still lubricated. On the left side you can see some “orange” looks like rust perhaps but it is assembly lube. Depending on the comments, I plan to put some assembly lube on the cap.
When I removed the nuts, the right side loosened at 50 lbs and the left side at 43 lbs. I did not try to tighten them first. I will do that on the #4 rod cap. Does anyone know the significance of the V F on the rod cap? The letters were on the front side.
Here are the pics from the #4 Rod Cap. I didn’t take anymore of the Journal as it looks the same as No. 3. I did test the tightening torque on this #4 rod. About 38 lb-ft to 40 lb-ft. Seems right at spec.
It is based on piston speeds. It has to accelerate the pistons and rods to higher speeds than many other engines, thus the ‚low‘ redline, but they’re built to take it.
Now what do you want to know?
There’s a way to check the bolts by measuring the increase in length when torquing to spec. If the bolt was soft or weak it might show. Are the bolts copper plated? They used to be, but not anymore from the 70s on or so.
Hi David. I’ve never opened an XK engine before. In sorting out this engine which has sat for 25 years after being rebuilt by a shop I have had no contact with, I’m wanting to verify the engine has been built properly. To that end, with advice from members here, I’ve decided to remove at least one rod journal plug, a couple of rod caps and possibly a main cap. If all seems in order, I’ll then re-torque the mains and rods and re-install the pan. The #3 and #4 rod caps have new bearing in them - that’s good. There was/is oil/lube on the bearing still - that’s good. I’ll remove one plug today to see if there’s sludge or if it is clean. The rod bolt’s look to me like original XKs; is that so? I do not see any sign of copper plating on the rod bolts. There has been quite a discussion on the rod bolts and the “chevy” nuts that were installed. Some say re-use them, others say not. It seems to me most have agreed on this thread that the main caps should have a hardened flat washer. Finally my intent is to coat the rod caps with more assembly lube and install them. Use the book values for the torque. Yeah or nay?
Good news here. With the #4 rod journal plug removed, it is apparent it had been cleaned before the machine shop did their work. Yeah! Removing the plug is not a fun job under the car even though I’ve a nice place to work in. Getting the pics to show the wide open oil passages within the plug was difficult to provide light and focus simultaneously. Still, it is pretty obvious that the passages are clean.
Note I’ve removed the plug from #4 as it was the easiest to access. Burr bit on the Dremel and my 1/2" impact driver brought it out. Lots of Dremel work that isn’t fun and hard on the neck. Glad I did it though. I also checked the torque on the mains. 83 lb-ft did not budge them, so I’ll leave them alone. Need to check the oil pump next.
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Oh, man, great news!
Royal PITA, but you can sleep better… soon as the bone cracker fixes yer neck.
Exactly! Thanks for your help!
IF the rod bolts are stock Jag, then the manual’s torque specs apply. If aftermarket bolts, then torque specs may well be higher to achieve proper bolt stretch.
Yea.
If you want I can look for stretch dimensions but torque them, put the rest together and it seems you have a good engine for the next years.
Copper plating is not so important, otherwise they wouldn’t have stopped doing it. It means nothing, you’re good, i was just curious.
If it were me, I’d use the OEM torque specs anyway. Presumably the bolts are the same shank size, stretch shouldn’t be that different. But you’re also talking about applying more compression to the cap itself, which might not be good. It might distort or something.
I hear you all. You all know the concerns I have over this engine’s history and indeed the entire car. due to the angst that must have existed between my aunt and uncle and the shops where they had the restoration back in 1990. I am just very careful to check everything as I bring this car to completion.
That said, the engine itself seems to have been done okay. I made a list of things to check and most I have now done with happy results. The remainder depend on my getting a usable oil pan. On the rod bolts, I don’t know how to verify if they are Jaguar or not having never seen one before. But they fit the rod and rod cap well and have the cotter pin hole. I’m going with them and the “chevy” rod caps and I’ve torque the bottom end to factory specs. Here’s my list for future readers who may read this thread.
David, no need for the stretch values; I used the torque specs. But thank you anyway. And thanks to all for your comments.
Secure tab washer on Oil Pipe bolt Yes
Verify there’s a gasket under the Oil Pipe and at the Oil Pump Yes
Verify the correct O-rings are at the Oil Pump inlet and outlet Yes
The pipes need to be snug inside the O-rings
Check Oil Pump Drive Dog to Distributor
Use short pan bolt at right front corner of pan Yes
3M adhesive remove to clean gasket material off Yes
Locktite 290 to prevent weeping leaks
Check to make sure baffle does not sit proud on any welds/repairs
Remove rod plug(s) to check for sludge. Re-stake rod plugs if necessary Yes
Replace baffle bolt with a proper stud
Remove one or two rod caps to check cleanliness and new bearings exist Yes
Removed #3 and #4. Both Okay
12-point Chevy Rod Nuts are a good choice, no washer underneath Yes
SNG rod nuts are $7.09 each = $85.08
Main nuts need a hardened flat washer underneath Yes
Remove one to verify
Book torque values are fine to use on these fasteners Yes
37.5 lbs-ft for Rods, 85 lb-ft for mains
Lastly: when you find/make a good sump… don’t forget to put oil in it.
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Funny. You must be snowed in or something! 
Snowing here in the Smokies today.
There is a good write-up on the oil pump started by Ron Smith. I’ll be reading that to check my own pump and its installation, drive dog, etc.
The rod and cap are a matched set, and marked as such.
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thanks Rob. On the exhaust side of the rod and the cap are stamped the cylinder position 1, 2 , 3, etc. The intake side has letters such as the V and F stamped on both the cap and the rod. They do match. I just can’t decipher why they used the letters they did. Each rod/cap are different from the others of course.
Tis one of the mysteries…
Watch this video at time marker 10:34;
The rods and caps are matched first and weighed, then stamped with the letters.
Then later on they are grouped into sets of six, stamped 1-6, and assigned to an engine.
Wow that’s a great video Rob. Thanks for providing it. We see they mark them to identify the crank to the engine, and the rods to their “weight lot” but not what the marks stand for. Interesting.
I have some 8Z, DX, H5, AD, ZK, YA, they could have started out at 00 and went via 0A, 0B, A0, AA etc. to ZY, ZZ and that would simply give them a lot of combinations to make sure caps and rods are not mixed up… then off to matching, 1…6 