Gasket crush??

[WilBury]

So, on a Case 188D rebuild, I was all worried about factoring in head gasket crush so I could nail down valve-to-piston clearance measurements.
I have come to believe "crush" only applies to the sealing qualities of the fire ring & gasket and sleeve hold-down pressure.
When torqued down, the head actually butts right up against the top of the sleeve.
Have I got that right now?

 

[WilBury]

I do tend to overcomplicate things...

What I meant to ask is, if sleeve protrusion is within spec, should the head contact the top of the sleeve?

 

[rustred]

impossible , the gasket fire ring is in between the block and head.

 

[John Saeli]

Not impossible. The head gasket seals on the outside edge of the sleeve. Just inside of that area is a raised portion of the sleeve. It's not impossible that the head would meet the raised portion before the gasket is fully crushed. On the 188's, there are 2 different sleeves, early & late and 2 different head gaskets. The late gasket which is furnished as a universal gasket will soon blow on the early sleeve. Sleeve protrusion is important but often overlooked. CASE recommends Re-Torquing the head, and spells out the procedure, but I have found only 1 in 100 know the procedure as CASE spells it out.

 

[rustred]

well ya its possible if you dont have the proper gasket, as in too thin, or a mix up of things. as you will notice that raised part of the sleeves have carbon on them when you take things apart. this is not the only engine like this. how is the case procedure retorque so different.? when things are removed they should be looked closely at and compared to the new parts. long as you had the correct stuff in the first place. so my answer is still correct , it does not contact the sleeve.

 

[WilBury]

Thanks for the replies! It's answers to details like this that I've only been able to find on this site thanks to all you "old-timing type folks". (I'm a youngster at 67, lol.) It's a darn good thing I started my research six months in advance. If one were to jump into a rebuild like this without the foreknowledge or the advice of a competent mechanic and/or machinist, you'd be opening yourself up to a world of hurt. Finding the right machine shop is proving a challenge tho, nearest one being 5 1/2 hours away!

Finally, after many hours of googling, I found a decent video showing how the head gasket fits on wet sleeves like these ones. Somewhere around the 4-5 minute mark...
https://www.youtube.com/watch?v=xaRLXpMvxhg&list=PLdiwqjO1xQV3-eNEHCeTzw442m-cXsl-X&index=13
While no one actually says there is contact, I'll bet you can see the imprint of the sleeve on the head when you take it off. Can anyone confirm?

John, I intend to upgrade my early 188D to the wide-flange sleeves (as per mEl's advice) & will, of course, use the appropriate kit. What brand of overhaul kit do you sell? All I can find is Reliance.

rustred, you may well be correct about non-contact. Carbon, eh? I guess that's why it's so important to properly inspect the block, head, sleeve & gasket on teardown to see what's going on. For retorquing I'll just follow the manual but I may throw in another retorque at 100 hours.

So, to answer my own question, I do believe gasket crush can be safely ignored when it comes to measuring valve-to-piston clearance (on this engine). On assembly, I can just carefully rest the head directly on the sleeve tops with a couple push rods in place, a few head bolts very lightly tightened and I should be able to accurately measure valve-to-piston clearance. At worst I may end up with a couple/few thou extra clearance.

Basically just looking for confirmation & this may help others with the same questions. As always, any criticism is welcome!

 

[John Saeli]

Red: In a perfect world, the gasket crush would be perfect and theoretically last forever. However, there is complaint that some aftermarket head gaskets are too thin and fail. We must assume that the heads are contacting the firedam on the sleeve before fully crushing the gasket. CASE says that on initial engine startup after replacing head gaskets, to bring engine up to operating temp. Then, using the tightening pattern, starting w/ number 1 bolt or nut, back off 1/4 turn and come back up to torque. Then move to #2 and so on. You will find that by getting a running start you will gain about 1/2 turn after coming back the initial 1/4. Some people don't attempt to re-torque, some simply put the wrench on & pull and nothing gives.

 

[John Saeli]

Reliance is what we sell. Guidance afterward is free.

 

[WilBury]

(quoted from post at 10:26:17 03/02/22) Reliance is what we sell. Guidance afterward is free.

Lol, fair enough John, fair enough...

Another possibility for carbon under there might be a sunk liner. This guy really knows his stuff.
https://www.youtube.com/watch?v=lEJ8sSD1uYs

 

[rustred]

yes, put some putty on the piston and see if the valves touch, and that should give you a better idea .

 

[WilBury]

Indeed, I'm gonna measure it with test springs & a gauge before disassembly and use putty on assembly.

 

[WilBury]

Oh, and my brother-in-law says guys are using the springs in toilet paper hangers for test springs. Half price!

 

[DanielW]

Something that MUST be considered whenever rebuilding a 188 (or 301), is that during
the early production years Case didn't have sleeve protrusion nailed down too well.
To compensate, the head-gasket and fire-rings were separate pieces. You bought the
gasket, and different fire ring thicknesses were available for different sleeve
protrusions. They finessed it for the later versions and went to the one-piece head-
gaskets with integral fire rings.

The old gaskets and separate fire rings are still available, but they're hard for any
dealer/person to find. They aren't visible in the parts books for the
tractor/equipment these were used on. Instead, you/the dealer has to look up the
engine/power unit on the parts lookup site, not the machine. The earlier SN's will be
shown in the engine section. If you look up the machine (ex. 430/530), it will only
list the newer style gasket.

I'd post part numbers, but the Case parts website has been wonky these past few weeks
(or maybe they've just removed a lot of the legacy equipment? I hope not).

I lucked out with this two years ago. A guy not far from me rebuilt the head, engine,
and injection pump on a 630 that was elsewise in great conditions. He put it back
together and coolant was getting in the crankcase. He figured the block was cracked.
I bought it very cheap, knowing it was a bit of a gamble, but sure enough it was just
the wrong gasket. I put the old style gasket with the thicker fire rings in and it
hasn't leaked a drop since. Ended up having a pretty much brand-new tractor for less
than $1800 (CDN).

 

[WilBury]

Daniel, I don't think I'm going to mess with separate fire rings. I found this page that images separate fire rings but I won't be pursuing it unless I run into the same trouble.
https://www.agkits.com/case-g188d-diesel-overhaul-gasket-set-rp321243.aspx
Looks like it was the right choice for you, but I will be having the block & counterbores machined to my specs, somewhere around .003 to .004 sleeve protrusion or whatever number I can squeeze out of the Reliance engineer/technician and agree with. I may contact FelPro as well if they're the gasket maker for Reliance.

To be sure, it's a real balancing act between head gasket sealing and fire ring clamping pressure where a couple thou can make all the difference. I'll likely go slightly to the high side of the spec on sleeve protrusion for tight fire rings.

Another point that some know & some don't is that the drilled bolt behind the water pump should be omitted and bolts from the timing cover to head should be loosened before retorquing the head.

CaseCe appears to have dropped the 188D from their engine section, if it was ever there... Can still be found under machine sections tho.
Wil