Top Head Clearance and Gasket

[wdlanning]

Rebuilding a D1503 from a L2900. Confused about minimum clearance with the head gasket installed.

Manual states acceptable protrusion is .50-.70mm. Mine measures about .70mm for all three cylinders. Another part of the manual specifies a head gasket number 35 for this measured height. My gasket is number 25. For a 25 gasket the protrusion specified is .575-.625mm.

Number 25 gasket is 1.25mm and may compress to 1.10mm. Substracting the .70mm protrusion leaves .4mm clearance. Manual does not specify minimum with the head installed.

I cannot find a #35 gasket (1G720-03631) or a part number for a shim.

Looking for advice/guidance as to whether I use it with minimum clearance or call a dealer.

 

[North Idaho Wolfman]

I think you might be overly complicating this.

There is only one gasket listed and no shim listed for that engine.

If you using a generic D1503 engine rebuild manual that's what's fouling you up, because that engine is used in different applications and has different specs for other applications.

The only gasket they list for your motors application is 16467-03310

https://www.messicks.com/part/16467-03310/gasket-cyl-hea

 

[wdlanning]

Wolfman,
I really appreciate your response. I was beginning to think I wasn't going to get any help.

I was using the Kubota manual for the specs. I can go and re-assembly the engine using the gasket I have.

How will I be able to determine if the clearance is too small before the cylinder hits the valves?

 

[Fordtech86]

Wolfman,
I really appreciate your response. I was beginning to think I wasn't going to get any help.

I was using the Kubota manual for the specs. I can go and re-assembly the engine using the gasket I have.

How will I be able to determine if the clearance is too small before the cylinder hits the valves?

After you get the head back on, turn the engine over by hand 2 full revolutions. Will be easy if you leave glow plugs and/or injectors out. If it’s spins freely the valves aren’t hitting the pistons

 

[North Idaho Wolfman]

The pistons can't hit the valves but if something is wrong they can hit the head.

If your worried at all you can do this measurement:
1/2 to 3/4 of a mm is one tiny measurement!
Or with the head on do a compression test:
For fuse, use soft plumbers or large soft electrical solder.