Valve seat issues

Billy Nees · 07-06-2016, 10:34 AM

Quote:

Originally Posted by SST3193

Is it caused by the lack of lead and the fact that the exhaust valves get hotter than the intakes?

Just an FYI, I got a good tip the other day about older engines. Put about an ounce of Marvel Mystery Oil per each 6-7 gallons of gas. Also works well in older engines with mechanical injectors. Diesels too.

Tom Goldman · 07-06-2016, 01:01 PM

I do some driveline work for a shop that specializes in Packards and they started experiencing valve seat wear similar to this many years ago .
They believe its due to heat generated by modern day gas having a much different burn rate than gas of the '30's.
Engine cooling also is effected by the use of glycol coolant as opposed to the alcohol mix that was used back then. It may not overheat ,but the dissipation rate is different .
They now use Evans Coolant in these type of cars
They install hardened seats in everything now and have no problems .
Also if the tappet face is worn or has not been resurfaced properly the valve may not be rotating.
X2 on Billy's suggestion , Marvel defiantly helps on these old engines ,especially the valve guides.

Bobby DiDomenico · 07-06-2016, 01:15 PM

Thanks guys. These cars all have serious drivability issues with todays gasoline, especially the ethanol summer blends we are forced to purchase here.

Tom, I'm afraid that cutting the seats again and removing more material is going to make it worse. The fact that there is not left to right issues seems to back up your cooling idea. My guess they now have antifreeze for sitting over the winter, he used to run maybe just some type of water in all of them? I'll find out.

Bobby DiDomenico · 07-13-2016, 11:35 AM

Exhaust manifold issue, any ideas on what could have caused this? Is a weld and machine a lasting repair? There is just a small area of material connecting the top and bottom portions that I'm estimating to be .125 deep. The exhaust valve to the right was the one with the worst seat issues. You can see the gasket is no longer sealing on the top of the ports where the manifold portions are no longer in line and eaten away.

Tom Goldman · 07-13-2016, 12:42 PM

Blast clean it to remove the carbon and pre heat to around 500 deg to help cook out any remaining carbon.
I TIG repairs like that using NickelCast 55 stick rods with the flux removed , makes a very nice ,durable repair ,especially on old castings.
I've used this method for blocks , heads and manifolds.

07-06-2016, 01:01 PM	#2
Tom Goldman VIP Member Join Date: Jan 2003 Location: Allentown,PA Posts: 2,477 Likes: 892 Liked 883 Times in 237 Posts	Re: Valve seat issues I do some driveline work for a shop that specializes in Packards and they started experiencing valve seat wear similar to this many years ago . They believe its due to heat generated by modern day gas having a much different burn rate than gas of the '30's. Engine cooling also is effected by the use of glycol coolant as opposed to the alcohol mix that was used back then. It may not overheat ,but the dissipation rate is different . They now use Evans Coolant in these type of cars They install hardened seats in everything now and have no problems . Also if the tappet face is worn or has not been resurfaced properly the valve may not be rotating. X2 on Billy's suggestion , Marvel defiantly helps on these old engines ,especially the valve guides. __________________ Tom Goldman 1500 SG , 1506 STK

07-06-2016, 01:15 PM	#3
Bobby DiDomenico Senior Member Join Date: Jun 2002 Posts: 924 Likes: 103 Liked 101 Times in 52 Posts	Re: Valve seat issues Thanks guys. These cars all have serious drivability issues with todays gasoline, especially the ethanol summer blends we are forced to purchase here. Tom, I'm afraid that cutting the seats again and removing more material is going to make it worse. The fact that there is not left to right issues seems to back up your cooling idea. My guess they now have antifreeze for sitting over the winter, he used to run maybe just some type of water in all of them? I'll find out.

07-13-2016, 11:35 AM	#4
Bobby DiDomenico Senior Member Join Date: Jun 2002 Posts: 924 Likes: 103 Liked 101 Times in 52 Posts	Re: Valve seat issues Exhaust manifold issue, any ideas on what could have caused this? Is a weld and machine a lasting repair? There is just a small area of material connecting the top and bottom portions that I'm estimating to be .125 deep. The exhaust valve to the right was the one with the worst seat issues. You can see the gasket is no longer sealing on the top of the ports where the manifold portions are no longer in line and eaten away. Attached Thumbnails Last edited by Bobby DiDomenico; 07-13-2016 at 11:38 AM.

07-13-2016, 12:42 PM	#5
Tom Goldman VIP Member Join Date: Jan 2003 Location: Allentown,PA Posts: 2,477 Likes: 892 Liked 883 Times in 237 Posts	Re: Valve seat issues Blast clean it to remove the carbon and pre heat to around 500 deg to help cook out any remaining carbon. I TIG repairs like that using NickelCast 55 stick rods with the flux removed , makes a very nice ,durable repair ,especially on old castings. I've used this method for blocks , heads and manifolds. __________________ Tom Goldman 1500 SG , 1506 STK

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