I’m assuming SWMBO was out when you did this. 
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or at least the children …
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Laughed.
HARD. Right out loud!!!
Bore gage arrived today. Initial results posted. I will reset and measure again tomorrow. Just to see if I did it right. *CLR=center, left, right. 60deg. (And whether C-nese tools are accurate)
Side note: the youngest helped by writing the measurements down… I guess that’s a start!
Steve, what are we measuring here? Out of round and cylinder taper? So the critical dimension is the change from the smallest dimension in any one cylinder? I assume this tool has a dial indicator and is rocked to achieve the smallest reading?
What is the piston skirt to cylinder diameter. ie. piston clearance?
David, correct about the rocking a dial indicator method. I will post photos of my procedure today when I remeasure.
OK this morning I am using a digital gauge and the readings I am getting are significantly better but before I go on I want to make sure that I’m doing this right?
Nevermind, I was just told of the method of turning the piston upside-down and inserting it into the cylinder. Then measuring the “skirt” 90deg. from the pin. Those measurements were BELOW 0.002". The ring landings were around… top ring=0.003" and bottom ring=0.002" typ. so looks like new rings AND pistons. I would like input on vendors/results regarding that (STD size, no oversize required)
This is GOOD news because having to do a TOTAL engine rebuild was going to be QUITE a delay waiting for funds…
Here’s how I learned back in the day.
Measure at 4 height levels in the cylinder, roughly equidistant.
At each level, measure the bore parallel to the pin, then at 90 deg to pin (the thrust side of piston).
Another area of concern is at the top of the bore, above where the rings travel. A slight ridge can form there from wear… Use your bore gauge to discern if there is a slight diameter decrease just above where the piston rings travel.
Measuring clearance with a feeler gauge is done by “feel”. You need extra long feeler gauges, at 90 deg to pin. A 7 lb. pull on the pin with a scale indicates the clearance is at the spec of the feeler gauge. Most machinists would laugh at the old school technique, and use an inside & outside micrometer and subtract the two for clearance. Your bore cannot be tapered or out of round for the feeler gauge technique to be valid.
David is largely correct: the critical measurement is the thrust faces, and that is better done with long feelers.
Good thing is, you only need a couple of them!
You always were going to need rings: the land wear you are seeing will require new pistons.
My long feeler gages arrived today. Can someone detail the best procedure for checking all 6 cylinders to determine the wear before I proceed?
btw Wiggles, the specs on the ring landings are 0.001"-0.003" so… In spec but do they make rings that will compensate to the tune of adding 0.001"-0.0005" to the landing?
Oh, and what tolerances qualifies as a good engine to just replace rings and liners?
-Steve
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I’d start asking around for someone’s unused rotisserie…yer gunna need it.
Hello all you current Jag S2 FHC drivers. Anyone done with their rotisserie?
As Roy Scheider said, “We’re going to need a bigger rotisserie”. He also said, “It’s the six”.
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Lets hope you dont need one of these.
https://www.martinrobey.com/Jaguar/interactive-parts/floor42/floor-assembly-42-large/
Hope not either, but… put me down as Steve will be in need of most of that.
Larry,
Serious work well done.
At least you had the panel you cannot purchase-the roof.
My next S1 FHC project has rotten floors and a bent roof! I think it may have been dropped on its roof 20 years ago.
I am going to have to brace all the door pillars together before attempt to straighten the roof out. The when it is straight I am going to attempt to remove the floors and rear inner wings in there entirety. At least the bulkhead is good on mine.
James, are you familiar with shrinking discs? I’ve had four. I bought the first one 20 or so years ago by Sunchaser Tools then when it cracked bought the second by Eastwood and I more recently (ie four years ago) bought the combo from Wray Schelin - just as effective as the others but much safer and less prone to failure. I have yet to meet a dent I couldn’t remove or oil canning I couldn’t flatten with a shrinking disc, provided there’s access to both sides of the panel. Seems to me straightening a coupe roof is an ideal application. No affliliation.
Edit. Very nice work, Larry.
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