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a_florida_man
a_florida_man GRM+ Memberand HalfDork
8/11/22 9:48 p.m.

Here's a question to the hive....

If I have to use the old rings with the used pistons, should I still de-glaze the cylinders?

I think so.

As I imagine the used pistons presenting the old rings to the bore in an ever so slightly different geometry.

 

And I would also like to acknowledge that this is possibly the most characteristic "$2000 Challenge" question ever asked.

 

I ordered one set of rings ($50 a Piston) for the smoked piston as the top ring no longer has the same unloaded gap as the rest.

Im assuming the blow by heat did that.

lol

 

 

frenchyd
frenchyd MegaDork
8/11/22 10:23 p.m.

In reply to a_florida_man :

Yes, but ever so lightly.  

a_florida_man
a_florida_man GRM+ Memberand HalfDork
8/14/22 11:22 a.m.

A little progress this weekend.

The used pistons gave back about 0.0010" to 0.0015", over the originals so there was a gain there, which was expected.

The Bores were straight and square, less than 0.0005" taper.

Piston to bore clearance is about 0.0035" total overall average.

The dingle ball put a beautiful finish on the bores with little effort.

I could not measure any difference pre / post ball honing.

The streak are some sort of optical trick. The bores look great!

Block sanded the deck with wd-40 and 1000 grit... it cleaned up well.

 

 

 

Next step is to do a final gasket and rtv channel check, chase the threads, and do a final wash for assembly.

 

a_florida_man
a_florida_man GRM+ Memberand HalfDork
8/14/22 11:30 a.m.

Additional note:

I kept the rings from the damaged cylinder.

On second look, the top ring had the same uncompressed gap as all of the other 7 top rings.

Also, in the new ring set, the oil control ring had VERY LITTLE uncompressed ring gap.

Its probably ok, but between my constantly imaging that the oil ring would be laying down on the job, and a desire for a balance in clearances (all cylinders will now have their original run in rings) i decided to pop'em back in. I polished the sides of the rings free of the minor corrosion from the original failure with a soft green used scotch brite pad.

Ring to groove fit feels great.

 

frenchyd
frenchyd MegaDork
8/14/22 11:50 a.m.

In reply to a_florida_man :

That is precisely the approach I would have taken.  Well done! 

a_florida_man
a_florida_man GRM+ Memberand HalfDork
8/14/22 11:52 a.m.

As the short block moves to assembly, the heads are of course next for overhaul.

The have been in the bucket for a week, and are now clean enough for disassembly and inspection.

 

a_florida_man
a_florida_man GRM+ Memberand HalfDork
8/14/22 11:54 a.m.
frenchyd said:

In reply to a_florida_man :

That is precisely the approach I would have taken.  Well done! 

Thanks!

a_florida_man
a_florida_man GRM+ Memberand HalfDork
8/15/22 9:35 p.m.

I just deleted a huge post before posting it.

UGH

Synopsis:

Topic is reusing TTY bolts. 

The crux of the issue is the older the jaguar service information, the more likely it is ok to reuse TTY bolts once or twice.

Even super long 8mm head bolts.  Meh--- use those twice more if you want. Especially if it warranty work (LOL).

 

So tonight I torqued (re-used) some m9 connecting rod bolts in a connecting rod (I had extras) as a test.

I cycled them 3 times. 

1. 11 ft lbs

2. 22 ft lbs

3. 90 deg.

 

No change in final torque (I know that's not a direct corollary to clamping force but I wasn't about setting up load cells lol.), no stretch, no necking down, still meshed threads perfectly with other old one use head bolts.

I'll probably cycle them 7 more times, well, just because 10 right?, all in an effort to see if there is any measurable degradation.

Anyone have thoughts on the subject?

 

Because, here's the deal, If I buy all of the TTY bolts for this build.... it's going to be > $500.

I have budget for that, but not the stomach.

:)

 

 

 

frenchyd
frenchyd MegaDork
8/15/22 11:12 p.m.

In reply to a_florida_man :

I understand why you're doing it.   I'm not sure I would. I think I would seek out some high grade steel.  Cut them to length, Run a die over  them to fit.  I did that when I couldn't get high grade bolts for my 3.8 Jaguar.  
    Since you are running supercharged  I would check with ARP  and steel supply houses.  

untchabl
untchabl HalfDork
8/15/22 11:34 p.m.

Sloppy Mechanics guys have been reusing TTY bolts successfully.

a_florida_man
a_florida_man GRM+ Memberand HalfDork
8/16/22 12:10 a.m.

So, it's not really black magic or any thing.

TTY bolts only have one advantage, consistent clamping force on the assembly line, attained by taking advantage of the elastic and or plastic deformation found on the stress strain curve for the fastener.

There is no other magic.

Manufacturers commonly state reuse intervals (one or two) or stretch limits on TTY bolts.

The question is how far does the fastener get pushed along the the flat plastic part of the stress and strain curve each time the fastener is used?

In this case, 10 measured applications of the fastener have yielded (pun intended ) zero deformation and a consistent torque.

So if it works ten times, surely a second round for me is ok.

I understand that reusing parts to save money, might COST money, but at the same time why spend money until you understand why you need to?

Like I'm sure there is no Jaguar approved manual that says, yeah, put your old rings on used pistons, dingle ball it and go.... :).

But we know we can, because we can visualize the dimensions, and the forces.

The mechanics of the fastener just requires a longer pause for thought.

 

Ill be considering each fastener individually, too.

Or maybe I won't and I'll drop $500 on hardware, lol....

 

The problem with not using TTY and replacing with traditional hardware is figuring out what static ammount of twist to apply to get the original designed clamping force. Also not impossible.

Robbie (Forum Supporter)
Robbie (Forum Supporter) MegaDork
8/16/22 1:25 p.m.

You're putting a lot more science into this that I probably would!

 

Gambit
Gambit Reader
8/16/22 4:42 p.m.

I see no in-between.. go straight to arp or just tty reuse with like 5/7th the specified tq and then subsequent amount rotations 

mfennell
mfennell Reader
8/16/22 4:46 p.m.

Prefacing that I don't know anything about anything: does a torque value + degree always actually mean TTY?  It sounds like your test bolts didn't truly 'yield' at all.

a_florida_man
a_florida_man GRM+ Memberand HalfDork
8/16/22 5:00 p.m.
mfennell said:

Prefacing that I don't know anything about anything: does a torque value + degree always actually mean TTY?  It sounds like your test bolts didn't truly 'yield' at all.

As a general rule I think it does. Add to that the oem recommendation to never reuse rod bolts. 
I think it's overkill.

I think jaguar is just barely getting close the plastic deformation range on  the rod bolts, for obvious reasons. There are only 2. Safety factor.

As a comparison I can clearly measure and identify the necked down portion of the head bolts. I don't have a reliable way to test those and they are really long and thin. So yeah going new there.

As for the bed plate bolts I think reuse there is going to be ok... idk still thinking out loud. :)

a_florida_man
a_florida_man GRM+ Memberand HalfDork
10/23/22 7:35 p.m.

woohooo! My parts from England showed up... now if I can just get the challenge moved to May...

a_florida_man
a_florida_man GRM+ Memberand HalfDork
10/24/22 1:04 p.m.

Crank bolt

cam bolts

midplate bolts

 

time to make the doughnuts

 

at home

 

not at the track in the parking lot

 

PMRacing
PMRacing GRM+ Memberand UltraDork
10/24/22 5:47 p.m.
a_florida_man said:

...put your old rings on used pistons, dingle ball it and go....

This sounds about right when said in a British accent.

nsogiba
nsogiba New Reader
1/6/23 9:51 a.m.

Cool rebuild, how's this thing coming? Excited to hear some V8 whiney noises. 

a_florida_man
a_florida_man GRM+ Memberand HalfDork
1/10/23 6:35 p.m.

In reply to nsogiba :

Me too!

The parts took F O R E V E R to come in.

Then the clutch in the Healey failed.

So the jag got bumped.....

But it is on deck so stay tuned.

worldwideds
worldwideds New Reader
1/20/23 10:31 a.m.

In reply to a_florida_man :

you know this is junk right...it's not a dana 44 in any way shape or form.

88-97 xj has the right part you want

a_florida_man
a_florida_man GRM+ Memberand HalfDork
1/22/23 9:49 p.m.

 

Well, I don't brag a lot... but sometimes I have too.

Read the far right side comments from my FB page post about the Healey, and how the Jag is next.

 

I married well. 

 

a_florida_man
a_florida_man GRM+ Memberand HalfDork
1/29/23 7:08 p.m.

Well, with a clutch in the Healey... it is out of the way, and its time to pull the XKR out of its sleep...

And by sleep I mean where it was outside under a liveoak tree.

It took at least 45minutes to clean all of the leaves out of the cowl and the space at the back of the top.

I did notice one good thing. The inside and the trunk were bone dry after being outside for 3 months.

Looks like the plugged gas door drain was the culprit. 

nsogiba
nsogiba New Reader
1/30/23 10:04 a.m.

Lots of potential! Can't wait!

Indy - Guy
Indy - Guy UltimaDork
1/31/23 3:55 p.m.

In reply to a_florida_man :

I'm glad to see this back at the front of the line and going into the garage again.  After seeing your work on the Healey, this car has definitely found the right owner. yes

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