what inserts are available and what is the size ? thanks
They're listed on Page 53 in Lang's catalogue, but the size isn't given. You could phone Lang's and ask.
Your best bet might be to take it to an automotive machine shop and have seats installed and guides reamed for Chevy 350 valves. Royce will tell you that you can recut the seats and ream the guides for Fordson tractor valves.
You can also use Ford 351 Windsor valves. They are a bit larger than the c%#@y vlaves and you still have quality parts in your motor. Scott
The machinists prefer you let them use the seats they have available as their machining is set up for the seats they use. I prefer the 350 exhaust valves as they are correct length for the adjustable tappets and the stems are slightly larger so the guides need to be reamed, taking care of worn guides. Remember the seats and reaming of the guides need to be done together!
I called Langs today as I am going to try and do my seats - they gave this info - seat is .732 thick,od 1 5/8th" id 1 5/16ths"
Tom, I think something is amiss with your Lang's seat dimensions. 0.732" is almost 3/4". Should the 7 be a 2?
I would be interested in how you intend to fit the seats. The machine shop I use has some rather sophisticated cutters and alignment tools for the job, not something I have seen in a home shop.
Allan from down under.
Allen is correct. Sounds like another block gone.
Tom:From what you have said the dimensions are off.
Instead of .732 it should be 7/32" or .218"
That's what is shown below typical model T seat we use.
are they cast iron or alloy? mark
Mark: The seats we use are an alloy nickel stellite seat.
I think you guys are right, sorry bout that I can't read my own writing :-)my eyes are not what they once were. oh yeah, I ordered mine from Mac's not Lang's. Their catalog says the seats are made of cast iron. I have not got them yet, still in the mail. Allen - I am going to try and do it - I picked up a Kwik - way valve seat insert tool model M-049 on E Bay, brand new never used best I can tell. Really lucked out as their quite expensive. Got it for about the price of a single cutter.I have never done anything like it. But I do know a couple skilled machinist who have offered to assist. Both have done valve seat inserts in several vehicles including model T's. So hopefully it well go ok. Thanks for pointing out my error's
Good buy Tom. I am not familiar with that tool. I hope it works for you. The seats have to be an interference fit. The cutter which makes the hole needs to be matched to the inserts to achieve this.
I am a little bit unsure about your proposal to use cast iron seats. The hardened seats in J and M's post will allow the use of unleaded fuels. These are tough little buggers. They need to be, to stand up to the hammer-in fitting process. I would be hesitant to fit cast iron seats in this way because of the risk of breaking them. I can see no advantage in using cast iron seats over the hardened seats.
Perhaps you skilled machinist helpers will be able to advise.
Yours with caution,
Allan from down under.
Doing it at home? Just under .015 interference fit. Wart removal kit with the liquid nitrogen, shrink it in.
Allan, unleaded fuels isn't a threat to the valve seats in a T like it is in more modern 30's to 60's higher revving engines.
I've read an english test from the 90's when unleaded was introduced here in Sweden & everybody was worried about their vintage cars. Their results: Almost all the extra wear cast iron seats gets without lead or equivalent protection in the fuel comes over 3000 rpm - and standard T driving is well below that, more like 1400 rpm.
I think that you have the decimal point off...
Lead wasn't added to gasoline commercially until 1923. The model T engine was designed for use with fuels not containing lead, so anyone stating that you need hardened seats for use with unleaded fuel is making an unsupportable statement. Hardened seats have merit for some reasons, but mitigation for damage brought on by the use of modern unleaded fuels isn't one of them.
After Lead was added to gas commercially in 1923, there was a moratorium put on it for testing purposes. (I suppose to prove that it wasn't harmful to people). Leaded gas took off after 1928.
I think .0015" ( one point five thousandths) would be just right for the interference fit.
I've only had to fit them to aluminium heads back in the 1970's,(Toyota) .007 was for that, checked my old ref book from back then for cast heads and .003 to .005 for them,(this is press fit) has it changed for what the seats are made from for today's specs?
So i forced my valve seats in far too tight?