- Engines:
- 3406 (S/N: 90U1-UP)
- 3406C (S/N: 1LS1-UP; 3ER1-UP; 4JK1-UP; 4TB1-UP; 4ZR1-UP; 8FS1-UP; 9ES1-UP)
Description of Change: New sleeves for the exhaust ports are now used on these engines. The new sleeve has a larger radius between the flange and the straight portion of the sleeve that is the port insulator. The weld has been moved further away from the flange.
Adaptable To: The new 194-8124 Sleeve is a direct replacement for the former 107-5670 Sleeve. The former sleeve has been cancelled. The new 194-8124 Sleeve is adaptable to all the listed engines.
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| Illustration 1 | g00739331 |
New 194-8124 Sleeve (A) Larger Radius | |
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| Illustration 2 | g00739332 |
Former 107-5670 Sleeve (B) Small Radius | |
Use a hand grinder and make a chamfer that is approximately 1.5 mm (0.06 inch) by 30 degrees around the outer edge of the exhaust ports in the cylinder head before the new 194-8124 Sleeves are installed in the cylinder head. The chamfer will provide clearance for the radius of the sleeve. The chamfer will prevent the sleeve from seating on a sharp edge when the exhaust manifold is installed. Refer to Illustration 3.
Note: The sleeves for the exhaust ports should be replaced during an engine overhaul.
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| Illustration 3 | g00739483 |
Cross section of exhaust port in cylinder head (C) 30 Degrees (D) 1.5 mm (0.06 inch) | |