Lead Substitute in Gas in Starting Engine?

[novavalleycat]

Is it advisable to use the lead substitute in the gas for the Cat starting engines?
I've been told that if not used it can be hard on valves. Any thoughts?

Thanks,
Jim Legge
in Nova Scotia

[SJ]

It is available as far as I know but it seems no more than they run at a time that it would be necessary to use it, just my opinion but I,m sure it wouldn,t hurt.

[bobcatd311]

My understanding is that when unleaded fuel came out it was thought that the valve seats of all gas engines (not just cat ponies) would experience accelerated wear but that this was not found to be the case and so it not necessary to use any treatments just use the unleaded fuel straight you may want to search around to confirm this

Bob

[u-joint]

i use chainsaw gas. the oil additive keeps the fuel from turning sour. and
believe it or not, it does not smoke like a two stroke, you cannot tell.

[tanker]

My understanding is that when unleaded fuel came out it was thought that the valve seats of all gas engines (not just cat ponies) would experience accelerated wear but that this was not found to be the case and so it not necessary to use any treatments just use the unleaded fuel straight

Bob

Funny- engines that didn't have hard or hardened seats- found their way into my shop--: post haste- ex valves tried to walk through the head..just my 1&1/2 cents worth..

[u-joint]

tanker, thats interesting. i have not yet seen a seat go bad due to what
i thought was a lack of lead. i have seen a few valves stick in the guides,
but never a seat. no one has ever been able to explain to me how a diet
of lead in the fuel is going to help the seats. i have found that the older
gas engines with the high tension piston rings seem to wear themselves
out at 100.000 miles. yes the valves and seats need work but the reason
i opened them up was due to the pistons, ring lands and cylinders.

back around 2000 i rebuilt a 1976 390 ford in a half ton two wheel drive.
the guy had 340 thousand miles on the engine. he went through two auto
transmissions before the engine gave up. the bottom end i believe would
have went another 300.000, but the heads were toast. all new valves,
seats and guides. the machine shop dude loved the oil spiral guides. i hate
them, seen two engines use oil because of them, with seals. i had him
install the smooth bore guides. he fitted them way tight on the valve. i
hoped for the best. within 500 miles the pick up came back with a stuck
intake. fixed that and within 6 months the old man got T boned and totalled
the rig.

[tanker]

Some heads have hardened seats w/o the typical insert that sometimes come out- cat built good stuff in the old days & the pony might have the hard option but I don't want to take the risk--as to valves walking through head- first one I saw was 318 plymouth-they were sunk to point the hyd lifters were starting to hold them open- time to fix- I do mostly racing stuff so lead is always in pic-local who does oem sees the problem & knows which heads are good & which are bad when it comes time for replacement..

[jmvmopar]

Chrysler started induction hardening valve seats in 1935. On modern engines they started hardening seats in 1969 on some engines and all engines were ready for unleaded gas with hardened seats by 1975.

You can buy lead substitute or used to be able too. If the valves are ground properly with a wide seat it should run just fine for years.

I found that lead substitute http://www.amazon.com/CD-2-Lead-Subs.../dp/B000E7HBTW. Try and buy it in CA though. I remember having a thing of that when I was in college and one of the greenies saw it and almost had a stroke.

[tanker]

. Try and buy it in CA though. I remember having a thing of that when I was in college and one of the greenies saw it and almost had a stroke.

Dats a good one- still lol- I got a 5 gal bucket of valve shield from nordland- think their out of St.Louis- $135 @ time- lot cheaper than a lot of other options & for me a lifetime supply..

[D4Jim]

For no more than it costs, I always use a lead substitute in my ponies and old engines for insurance.

I agree with tanker on ruined valves in old engines with unleaded gas. I needed a valve job in my 66 Ford PU after 6000 miles on unleaded. Man were the seats shot!! Re-done with hardened seats and runs great.

I am a believer in Lead substitute in old engines.