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Cat 3306 - Part # 8M4448 O-ring mystery ???

TEX32

TEX32

Well-Known Member
Joined
Feb 5, 2018
Messages
45
Location
Sault Ste Marie, ONT, Canada
Occupation
Owner, Technician @ INTEGRITY HEAVY REPAIR INC.
Morning gents.

Have a mystery here. Doing a head gasket job on a Cat 3306 ( Ser # 6NC17941 ) in a D7R ( Ser # 2EN01011 )

Installing rocker shaft assembly, and have an o-ring in my possession ( Part # 8M4448 ) that is supposed to be installed under #6 rocker shaft pedestal. However, there is NO groove or cut out in the cylinder head OR pedestal base for this o-ring to sit in. If I install this o-ring as is, it will levitate the pedestal and obviously will squish out / be damaged and won't allow for proper torque. I have contacted Caterpillar parts regarding my query, with my machine serial AND engine serial numbers. As per their breakdown, this o-ring DOES IN FACT install in this location... ???

Has anyone seen this issue before?

Tex
 
Nige

Nige

Senior Member
Joined
Jun 22, 2011
Messages
29,377
Location
G..G..G..Granville.........!! Fetch your cloth.
Tex, The engine S/N is the original one fitted to the tractor when built but is there any way you can tell if the head is the original one from the engine..?
Also was there an O-Ring in the assembly when it was pulled apart..?

EDIT: Scratch that. The O-Ring goes in the rocker shaft pedestal and that particular one is an oddball number compared to all the others. Pedestals mixed up somehow..? Somebody did a previous repair and installed a wrong one.? Any visible number on the pedestal.?

BTW you still owe me that case of beer for sorting out the calibration issue on your loader.......:p:p
 
Last edited:
TEX32

TEX32

Well-Known Member
Joined
Feb 5, 2018
Messages
45
Location
Sault Ste Marie, ONT, Canada
Occupation
Owner, Technician @ INTEGRITY HEAVY REPAIR INC.
I most certainly do! However, you still haven't told me where Granville is...

Owned the machine for 10+ years, head never off. Head is original to the engine ( as per numbers ) No o-ring there when disassembled, Pedestals / rocker shaft not disassembled, AND finally, no part number...
 
TEX32

TEX32

Well-Known Member
Joined
Feb 5, 2018
Messages
45
Location
Sault Ste Marie, ONT, Canada
Occupation
Owner, Technician @ INTEGRITY HEAVY REPAIR INC.
This is in fact a spacer plate engine, and there is not place for the o-ring to go. As per the pic on the right, my pedestal does not have a groove inside for an o-ring.
 
TEX32

TEX32

Well-Known Member
Joined
Feb 5, 2018
Messages
45
Location
Sault Ste Marie, ONT, Canada
Occupation
Owner, Technician @ INTEGRITY HEAVY REPAIR INC.
Nige said:
Is the pedestal that's supposed to have the O-Ring in it significantly different to all the others..? It ought to be.
Click to expand...
Nige, yes. It is slightly bigger, and has an oil passage hole drilled in it, off to the side of the bolt hole. ( as pictured )
 
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