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| | | Forums66 Topics128,077 Posts1,055,932 Members48,430 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | Some one told me today that I shouldn't run unleaded fuel in my 53 truck because it will burn the valves. I was sure it was the other way around, that you shouldn't put leaded fuel in an unleaded engine.
Who's right??? | | | | | Joined: Jan 2006 Posts: 74 'Bolter | | 'Bolter Joined: Jan 2006 Posts: 74 | I believe you are but I could be wrong | | | | | Joined: Oct 2005 Posts: 738 Shop Shark | | Shop Shark Joined: Oct 2005 Posts: 738 | I have heard the same thing about my 61. My friend was telling me that since my truck was built in the days of leaded gas it had "soft" valve seats. He claimed that newer vehicles designed for unleaded fuels have "hard" valve seats. I am not sure if he is right or not but he was sure that he was. I run unleaded gas in my truck and have for years, no problems yet. I put fuel conditioner through it once in a while, but nothing serious, just cheap NAPA stuff. I do that about every oil change or so. I am not sure if it does anything but I feel better about it.
"Never tell people how to do things. Tell them what to do and they will surprise you with their ingenuity." - George S. Patton My Machine | | | | | Joined: Mar 2004 Posts: 3,068 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 3,068 | Leaded fuel, if you could find it, will plug the catalydic converter. Running unleaded fuel in an old engine could theoretically could burn a valve or seat because they used the lead as a lubricant. You would have to run along time with an overlean condition to do it though. I'm still running original engines in most of my trucks with no problems, Scott | | | | | Joined: Jun 2005 Posts: 1,756 Shop Shark | | Shop Shark Joined: Jun 2005 Posts: 1,756 | Heard the same things, was told the valve seats would burn out and should be replaced with newer type seats (not the valves) | | | | | Joined: Feb 2003 Posts: 452 Shop Shark | | Shop Shark Joined: Feb 2003 Posts: 452 | Resto book I read said that the old seats are soft, but if it ran on leaded for any length of time, the lead is absorbed into the seat and provides lubrication for a long time. If you rebuild the head or use an NOS head with no milage, get the seats replaced with hardened ones.
Current fleet (subject to change w/o notice) \'49 GMC 3/4-Ton , 60 Austin Healey Frog-eye Sprite (some assembly required), 2011 Dodge Avenger, 2015 Jeep Cherokee. No, they don't all run. My other ride is a (B737)no, (B767)no, A320.... Update... was Embraer E190, now Boeing B787. Knowledge is a wonderful thing, but ignorance means you don't know you can't do something.
| | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | Thanks Guys... I was not planning on doing any internal work on the engine.
Since this truck will likely be a weekend cruiser and not a daily driver I think I will take my chances. It has 83000 on the odo so it probably had a few gallons of leaded fuel in its day. not too worried then. Rich | | | | | Joined: Apr 2005 Posts: 313 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 313 | I've been running my 1966 250 for over 11 years on unleaded, and it still runs fine. | | | | | Joined: Oct 2005 Posts: 41 New Guy | | New Guy Joined: Oct 2005 Posts: 41 | If you have concerns about this, there's a product I use in my big block Vette called max lead 2000. It adds actual tetrethyl lead and boosts octane. For the occasional driver, you can add some every 3rd or 4th tankful. http://www.maxlead2000.com/
You never have enough, til you have too many!
| | | | | Joined: Nov 2004 Posts: 2,404 Former Workshop Owner | | Former Workshop Owner Joined: Nov 2004 Posts: 2,404 | I wouldn't lose any sleep over it. I burn regular unleaded in my '59, not a problem yet.
Although, I would not burn Ethanol.
~ J Lucas 2006 GMC Envoy 4.2 I6 2023 Ram 2500/Cumins 6.7 I6 2010 Jeep Grand Cherokee (Wife’s) 2002 Silverado 2500 Gas 6.0 1941 Chevy 1/2-Ton 1942 Chevy 1.5-Ton SWBIn the Gallery My Flicker Photos! | | | | | Joined: Feb 2006 Posts: 1,867 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 1,867 | I heard that most of the sixs were such low rev engines it wouldnt be a problem but V8s would be effected, but by the time they were they would be darn near ready for a rebuild anyways. If you hear no pings or knocks go for it!
I recently got a 53 with a 216 and spent about 40$ on gas this last weekend (I just got her road worthy and was a little excited!) running all over town and no pinging and Im not gonna change a thing. -Jeff | | | | | Joined: Oct 2004 Posts: 235 Wrench Fetcher | | Wrench Fetcher Joined: Oct 2004 Posts: 235 | Before I got the 41 I ran my old Rover cars with inline six motors on unleaded gas for years without any problems. I think Jeff hit the nail on the head, these low revving motors driven normally shouldn't be a problem. Think of the muck they used to run on during WW2.Come rebuild time it would be sensible to put in hardened seats while its stripped down. Just my two bobs worth.
Cheers
Bob | | | | | Joined: Oct 2005 Posts: 688 Shop Shark | | Shop Shark Joined: Oct 2005 Posts: 688 | I agree with Mozzie. Cliff59 | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | The big problem will be if you run your vehicle under extreme load a lot. Running the vehicle hard will have more of a tendancy to wear the seats. As a daily driver you would probably only loose 15% of your valve/seat life. Thats 15,000 miles out of 100,000 miles. Not worth getting excited about unless you are doing an overhaul already. | | | | | Joined: Dec 2005 Posts: 324 Member | | Member Joined: Dec 2005 Posts: 324 | want to be safe? NAPA has a cheap "lead" subtitute about 1 oz for 5 gallon gas.
"It ain't a truck if you can't hose out the cab."
| | | | | Joined: Jan 2005 Posts: 192 Member | | Member Joined: Jan 2005 Posts: 192 | i met this elderly gent and while we were talkin trucks he was puting fuel in his newer 90's truck he took out a bottle of tranny fluid and put two capfuls in the tank,,,said it helped to keep things lubbed up,,,never tried it myself. anybody else heard of this...this ol timer swore by it and said he never had to rebuild an engine .his cars and trucks fell apart first | | | | | Joined: Mar 2004 Posts: 3,068 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 3,068 | But in this day in age, we're pulling down 2-300,000 mile on an engine with just maintenance like oil changes, nothing major. So how would you know? Scott | | | | | Joined: Apr 2005 Posts: 926 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 926 | If you have worries about valve seat damage from lack of lubrication with unleaded,add a couple of capfuls of Marvel Mystery Oil to the tank before every other fill up. As a sidenote,it seems to improve the octane of the gas by about a grade. I don't know how it does it,maybe it "fools" the engine into thinking the octane is higher,but it enabled me to run regular no-lead in my old Harley FLH,when it used to ping with anything less than 90 octane. Speed | | | | | Joined: Aug 2004 Posts: 399 Shop Shark | | Shop Shark Joined: Aug 2004 Posts: 399 | When did they invent leaded gas in the US? Here in Germany there was no lead in gas till 1957. So all the pre 1960 engines can handle it without any problem I drove 216s, 235s since years with unleaded and had any kind a problems :rolleyes: but never a valve problem. We even do quatermile with that, never heard about no-lead related problems from my Hotrod friends and we do a lot of abuse. Frank | | | | | Joined: Apr 2005 Posts: 313 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 313 | I think it was around 1924. | | | | | Joined: May 2023 Posts: 13 'Bolter | | 'Bolter Joined: May 2023 Posts: 13 | I have a 1960 Apache with a 235 in it. Is it safe to run the 95 octane non ethanol gas in it? | | | | | Joined: Jan 2022 Posts: 2,449 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,449 | Yes, until your wallet gets empty.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Mar 2021 Posts: 430 'Bolter | | 'Bolter Joined: Mar 2021 Posts: 430 | Since that is the closest to what it ran on in the 60's yep. only thing closer is leaded gas.  But if you want to help your wallet like Bill is thinking. Then not to worry about running it on standard gas at the pump. Other than you will want to keep a eye on your fuel lines if they are original. With the ethanol at higher concentrations. | | | | | Joined: May 2023 Posts: 13 'Bolter | | 'Bolter Joined: May 2023 Posts: 13 | Is there an additive that can be ran with regular 87 to counteract the ethanol? | | | | | Joined: Jan 2016 Posts: 1,101 'Bolter | | 'Bolter Joined: Jan 2016 Posts: 1,101 | There is an app for your phone called "Pure Gas" that will list gas stations near you that sell non-ethanol gas. I was told by an old school mechanic (which fits the description for most of this group) that it is more important to have a zinc additive in your oil than it is to have a lead additive in your gas. If you have a rebuilt carburetor the ethanol is probably not an issue as long as you don't let gas sit in the truck for long periods of time, such as winter storage. | | | | | Joined: Mar 2021 Posts: 430 'Bolter | | 'Bolter Joined: Mar 2021 Posts: 430 | Think of it this way. If your only driving it on the weekends and not hundreds and hundreds of miles. Fill it up with non-ethanol gas. Less likely to foul the lines or carb. and your wallet will be fine the few times you fill her up. If its your daily run it on 87. You wont have to worry about the carb it wont have any sitting gas and all you will need to inspect or just go ahead and replace is any old rubber gas lines with modern stock. The short version anyway. | | | | | Joined: Oct 2021 Posts: 6,772 'Bolter | | 'Bolter Joined: Oct 2021 Posts: 6,772 | I've been driving my entire fleet on ethanol fuel since it was mandated in Atlanta in about 2007.
The only problem it ever caused me was ruining the diaphragm in the original fuel pump in my 1956 Cadillac. After an ethanol resistant pump was installed, I had no further issues.
Ethanol is crap but if you drive your truck regularly you won't have any problems with it. The 235 will be just fine on 87 octane corn juice.
I've put over 3000 miles on my 1950 216 running on ethanol.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
| | | | | Joined: Nov 2020 Posts: 788 'Bolter | | 'Bolter Joined: Nov 2020 Posts: 788 | “… ethanol is probably not an issue so long as …” Beware the qualifiers.
“ Ethanol is crap…” Words to live by.
Corn is good for: -Eating -Popping and eating -Feeding to cows, (later eating said cows) -Making likker -Fishing bait (perch)
Note that which is conspicuously absent from that list.
Last edited by Waveski; 05/26/2023 4:28 PM.
| | | | | Joined: Mar 2014 Posts: 4,483 Moderator, Electrical Bay | | Moderator, Electrical Bay Joined: Mar 2014 Posts: 4,483 | Is there an additive that can be ran with regular 87 to counteract the ethanol? Sta-Bil 360 has been working for me. I haven't had any problems since I started using it about 2.5 or 3 years ago. I bought it on Amazon (large bottle) and it has a handy measuring device on the bottle.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
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