Hardened Valve Seats?


Forum designed for the D series and older

Rookie
Rookie

Posts: 4

Joined: Mon Mar 18, 2013 10:42 am

Post Tue Dec 03, 2019 7:28 pm

Hardened Valve Seats?

I'm slowly restoring(?) a '35 C-1 pickup with the flathead 6. I have the engine torn down and am wondering if it would be worth it to have a local machine shop install hardened valve seats in the block. I have been told it's only necessary to install hardened seats for the exhaust valves, the intakes can be left alone. I only intend to drive the truck around town, little or no 55mph freeway driving, and less than 500 miles per year. Is it worth it, or should I assemble the engine as is and use a "lead substitute" fuel additive? What do y'all think?
Brian

Golden Jubilee
Golden Jubilee

Posts: 4068

Joined: Thu Nov 29, 2012 9:28 pm

Location: Lyman, IA

Post Tue Dec 03, 2019 8:05 pm

Re: Hardened Valve Seats?

Run it as is. I don't know how many miles I have put on my stone stock BLD, and I was working it with a load. The Lead issue was way overblown. If and when a seat develops a problem then deal with it. Not in your, your kids or their kids lfetime if you are only putting 500 miles a year on it.

Rookie
Rookie

Posts: 4

Joined: Mon Mar 18, 2013 10:42 am

Post Tue Dec 03, 2019 8:41 pm

Re: Hardened Valve Seats?

Cornbinder:
Thanks for the quick reply, I plan to go with your suggestion.
Brian

Golden Jubilee
Golden Jubilee

Posts: 4068

Joined: Thu Nov 29, 2012 9:28 pm

Location: Lyman, IA

Post Tue Dec 03, 2019 8:47 pm

Re: Hardened Valve Seats?

Had my BLD moving 18K for 400 miles. EIther wide open or all the way off the throttle. If I was going to have valve seat issues, it would have shown itself by now! That sound like I was working harder than your engine will see in its lifetime.

Golden Jubilee
Golden Jubilee

Posts: 7561

Joined: Thu Dec 27, 2012 12:45 pm

Location: Canada's left Coast

Post Tue Dec 03, 2019 10:13 pm

Re: Hardened Valve Seats?

Ethyl Lead was put into gasoline to raise the octane.
Google octane. It may not be what you think it is.
The Ethyl Lead after combustion settled out in the sump, as sludge. Lead deposited on valves and around the combustion chamber. Ethyl lead was an inexpensive solution to a problem It was likely the oil companies who started the BS about the lead being a valve seat saver. I have seen many engines with burned valves and seats. A piece of hardened lead deposit has held a valve open a few thousands of and inch. The flash heat of the combustion acted like a cutting torch and often cut a notch in the valve and the seat.
Leaded fuel was in use around the time of hydraulic valve lifers being installed in engines. Maybe, just maybe, some of the "country" mechanics set the valves incorrectly and there was a valve failure.
These old engines will always have a sludging situation, but, it will never be the same as it was in the bad-ol-daze.
Never discount the simple bypass oilfilter system. Eventually, all of the oil will have passed through the filter.
Back in the day, it was often truthfully said, "There are no old mechanics." It was the lead that was killing them. You will know you have lead poisoning when your pecker does not respond to stimulus.
https://www.medicalnewstoday.com/articles/306601.php
I would rather have tools I do not need than to need tools I do not have

Golden Jubilee
Golden Jubilee

Posts: 7561

Joined: Thu Dec 27, 2012 12:45 pm

Location: Canada's left Coast

Post Tue Dec 03, 2019 10:27 pm

Re: Hardened Valve Seats?

Back in the 1950s, my brother and I bought a mid fifties Chrysler with a HEMI engine and an automatic transmission. We wanted the HEMI for a 1934 Ford we were working on.
We got the HEMI Chrysler from Farmer Jones Cars in Calgary. The car was $50 and we drove it home.
The HEMI ran, but it misfired and was low on power. My brother pulled the cylinder heads for a-look-see. Almost every valve was badly burned and one valve seat had burned into the castiron of the head. The lead deposits had held most of the valve open just a little.
The repair was beyond the budget of two boys with paper routs and after-school jobs.
Lead deposits will heat up enough to ignite an air-fuel mixture. This can act like a second sparkplug. Sometimes the heavy detonation you can hear is from colliding flame fronts from the spark and the glowing deposit.
BTW. the car went to a scrap dealer and we got $100 for the HEMI.
I would rather have tools I do not need than to need tools I do not have

Return to 1940 and Older

Who is online

Users browsing this forum: No registered users and 0 guests

Powered by phpBB® Forum Software © phpBB Group
Designed by ST Software for PTF.