Massey Harris 444 Exhaust Valve Seat Inserts

[FarmerHR]

.We are going over the H277 Continental gas egine in our Massey Harris Row Crop 444 tractor.The serial number is 70xxx.
I believe is was manufactured in 1956.
We have pulled the head and have been going over it. Our repair manual states that the exhaust valves have inserts for
the valve seats. Exhaust valves 1 & 4 show considerable wear but are probably still functional. Ehaust Valves 2 & 3 look
great. All the intake valves also look great.
The material used in exhaust inserts 1 & 4 is quite differennt than the material used in exhaust inserts 2 & 3 . The
material in exhaust inserts 2 & 3 is very shinny and is about the color of chrome platting. They stand out visually.
The material used in exhaust inserts 1 & 4 looks like the cast iron used in the rest of the head. The parting line
between the head and exhaust inserts 1 & 4 is very hard to see. Ehaust inserts 1 & 4 also show considerablly more wear
than exhaust inserts 2 & 3.
Has anyone run into this apparewnt difference in materials before ?
We have owned this tractor about 25 years. We do not know who owned the tractor before us or what they might have
repaired/changed.
We are planning to try having a machine shop change the exhaust insets on vales 1 & 4.
We would sincerely appreciate any wisdom anyone can share with us.

 

[wore out]

The shiny inserts are Stellite, a very hard and heat-resistant material, GOOD for exhaust seat use.

It is/was very routine for machine shops to install aftermarket valve seats, K. O. Lee was one supplier for a wide variety of seats and the tooling to install them.

If there's anyone at the machine shop with gray hair they would surely be aware of that.

I'm not sure if that engine could have had Stellite seats from the factory, either way, either two Stellite seats could have been replaced with ordinary valve seats, or, more likely two worn original valve seats were replaced with Stellite seats.

This post was edited by wore out on 11/03/2023 at 09:27 pm.

 

[John Deere D]

Are you sure there are Valve seat INSERTS installed beneath all Valves?
Thanks

Bob...

 

[J. Schwiebert]

They may be alloy not stellite Much more common

 

[EP]

You have 2 cast seats and 2 good alloy seats

 

[FarmerHR]

Thank you for your help. I appreciate your kindness.
Only the exhaust valves have inserts. The intake valves do not appear to have inserts.
Best Wishes !