Tuthill 3M34-JX767 Cover Gasket for 3C and 4C Series Gear Pumps
The Tuthill 3M34-JX767 is a genuine cover gasket for Tuthill 3C1E and 4C1E cast iron gear pumps. On a Tuthill gear pump the cover gasket does two jobs at once: it seals the joint, and its thickness sets the running clearance between the rotor and the cover. Fitting the wrong thickness will either cost capacity or let the rotor touch the cover.
The C Series parts lists call for two of these gaskets per pump rather than one, so order in pairs. The equivalent gasket on the size 2 pumps is 2M34-JX726, which is not interchangeable, and the aluminum and nitrile laminate construction is what lets the gasket hold a clamped joint at the cover without extruding. Before the cover comes off, mark it against the housing so it goes back in the same orientation. Then clean both faces properly, because a scrap of old gasket left behind changes the clearance just as surely as the wrong part would.
Key Features
- Genuine Tuthill cover gasket
- Direct replacement for 3C and 4C Series builds
- Supplied at aluminum and Buna-N laminate, one of the published thicknesses in this family
- Parts list calls for 2 per pump
- Single use item that is replaced every time the joint is opened
- Cheap insurance against a leak or a lost pump cover
Applications
- Lubrication circuits on compressors, gearboxes and engines
- Burner oil and fuel oil transfer and circulation
- Low pressure hydraulic supply circuits
- Heat transfer oil and quench oil service
- Scheduled overhaul of Tuthill rotary gear pumps
- Spares holding for equipment that cannot afford downtime
Specifications
- Brand: Tuthill
- Manufacturer Part Number: 3M34-JX767
- Part Type: Cover Gasket
- Fits: Tuthill 3C1E and 4C1E cast iron gear pumps
- Thickness: aluminum and Buna-N laminate
- Quantity Required: 2
- Condition: New
Frequently Asked Questions
Q: Which thickness should I order?
Work from the clearance you measure, not from what came out. A worn pump usually wants a thinner gasket and a hot duty usually wants a thicker one.
Q: Can I stack two gaskets to make up a thickness?
Only if the parts list says so. Stacking gaskets that were not designed for it leaves a joint that relaxes and weeps.
Q: What happens if it is too thin?
The rotor will touch the cover as the pump warms and the parts grow. That shows up as noise, heat and, if it is left, scoring on the cover face.
Q: Should I mark the cover before removing it?
Yes. The service instructions call for it. A cover refitted a quarter turn out can change how the pump sits against its piping and its mount.
Not sure this is the right part? Send us a Picture of the Pump Plate on your pump and the CLR Marine team will confirm the correct gasket.
CLRMarine
