Head gasket

[Cat u9 u9]

On a cat D7 17 A is there a copper ring on top
Of the cylinder sleeve
The head gasket goes around the sleeve
All of my cylinders are leaking like I
Left out a part
This is why I'm getting psi in the coolant system
I don't think my liners have dropped there
Above the block
I really think I'm leving something out
 

[Old Magnet]

There is no ring on top.
Head gasket should get squeezed between the liner flange and the head. Still need to know the actual liner height above the block and the liners need to be clamped down to properly check the height.
If the head gasket fits around the outside of the liner, it's the wrong one.
 

[Cat u9 u9]

Well that's some good information
Just the wrong gasket
That tears it
The liners above block I need to
Put pressure against it an see how
Much is out 2 to 6 thou is ok
Then get the right gaskets
I used the part number out of a book
Got then from heavy equipment
U got a better number r just call cat
Thanks magnet
Other than blowing the water out the
Radatior she's a hoss maybe she'll live
Again
 

[just thinkin]

The ring you are talking about is it a fire ring?
That carbon ring may be a fire ring designed to keep the compression in the cylinder and away from the head gasket. Pinching head gasket material down on top of a liner that is not some type of metal is not going to prevent compression from leaking into water jacket.
Case uses fire rings on their tractors. Gaskets come from Case without the rings and you must buy them seperate. Some after market Case gaskets have the fire rings in them. Make sure you have the right gasket as it sounds as compression is getting in water and the exhaust would make temp run high. Does it seem to be worse when you load it hard and the boost is up?
 

[Old Magnet]

My original service manual and parts manual does not call out any separate sealing ring. Don't know what the current appraoch in head gaskets might be. From the service manual illustration (not great) original appears to be a single thickness metal, maybe copper. Doesn't appear to be a fire ring to it.
Does appear to have a step to the liner flange.
 

[Old Magnet]

What is the s/n of the tractor and which heads are you using? They used two different gasket numbers for early and late but the transition numbers jump around a bit. Choice is 4H7440 early and 7H9983 late. The part # for the early heads is 5H7169 with a casting # 4H7104.
 

[Cat u9 u9]

The number is 17a13054
 

[Old Magnet]

That uses the later # 7H9983 head gasket (x2).
 

[Old Magnet]

Got to looking closer at the parts book and there are actually two gaskets per head. a 7H9983 and a 7H1582, the second one is on the cylinder side. Maybe that is the answer to your situation. No reference is made to this in the service manual so I'd recommend checking with Cat on this....sorry I didn't catch it sooner. "just thinking" was on to it.

You still need to do the liner height check as it appears you have been running without the liners being restrained due to the missing gasket.
 

[Cat u9 u9]

Mad dash to cat to get the same gaskets
1S-9397 that's the number on all the gaskets
Today but they don't go over the liner eather
But n talking to cat they found some other gasket
They didnt give me the part nub but I got some
Coming Monday
I'm thinking of cleaning it up real good an
Putting some clay on top the liner checking it
Out measuring it making some shimm stock
But I don't know thanks
 

[Old Magnet]

The 7H9983 has been replaced by a 4S5755.
The 7H1582 has been replaced by a 1S9397.

Both are available at Heavyquip or Regal and many other aftermarket suppliers as well as Cat.

Get the right stuff, put it together and be done with it. Cobbling it up is just going to lead to more problems. The 17A is a really good unit if built right.
 

[Bob/Ont]

NO!!!!!, if the liners are low, machine and shim the seats to get the height right.
About the extra gaskets Pete just mentioned, they are for around the push rods. They should be metal with silicone rubber bonded to them.
Later Bob
 

[Old Magnet]

Hi Bob,
The 7H9983/4S5755 is a composition gasket that goes on the pushrod side. Only one of these gaskets is used per 2-cylinder head.

The 7H1582/1S9397 goes to the piston side, again only one used per head. Can't tell what the material is but I suspect it is copper.

Seems this gasket was left out?????
 

[Cat u9 u9]

Pulling liners found a crack in one making her
New again thanks for your research
I'll contiue on with the repair on a new heading
Thanks again y'all r keeping the old iron alive