Any Fuel System Cleaners to avoid with an old carburetor?

[TacoFergie]

Are there any fuel system cleaners to avoid that may damage seals or other components I'm not aware of in older vehicles? Is PEA something to avoid or another chemical?

I fix and maintain my FiL's old trucks that all have their original carbs. One of them is a 1966 Chevy C10 with the original 327 with the stock 2 barrel that we're finally getting around to putting it on the road again until it's turn comes up to restore it. The others are a 71 Ford F100 390 with the stock 2 barrel, 57 Chevy 3100 with a 261 with original carb and a 49 Chevy 3100 stock 216. The tanks are clean on all of them. My main goal is to use an FSC to clean up and varnish and keep the carbs clean inside without tearing them apart. They all run well (except the 49, it's under the knife for restoration) and I'd like to keep them that way. The 66 has been sitting for about 8 years. After putting some fresh gas in it, it pops right off and runs quite well. But I'm sure the inside of the carb is varnished a bit from the old fuel based off what I pulled from the tank. They all get 91 octane as it's the only non-ethanol option in my area. My go to so far has been B12 for the old trucks, which I'm sure is doing it's job. But I also have a stack of VRP FSC from the current sales and I do really like Redline SL1 and Techron, just not sure if those would cause any issues? I'm probably overthinkning this, reel me in guys.

And becuase we all like pictures....

 

[Brian123]

. The 66 has been sitting for about 8 years. After putting some fresh gas in it, it pops right off and runs quite well. But I'm sure the inside of the carb is varnished a bit from the old fuel based off what I pulled from the tank.

Run a bit of Mechanic in a Bottle and see what happens! Then again, it did start, so the Carburetor should be fine.
My Dad does have a Honda pressure washer that was left in the basement for 4 years with fuel in the tank. When it was put in the basement, I did pour a few ounces of MMO into the carburetor opening, a few weeks ago it did start up, I did not think it was going to start up, it was like a miracle, yes, I had the water running out of the pressure washer while the engine ran. I ran the old gas out for like 20 minutes and then put in fresh gas with a bit of Mechanic In A Bottle!

 

[fantastic]

I like running berryman B12 in carb'd engines. Cool truck! Dad would leave us his 65 at the top of road for us to drive down after school & at 9-10 yrs old you can imagine the fun we had along the way. Yes it was a private road.

 

[TacoFergie]

Run a bit of Mechanic in a Bottle and see what happens! Then again, it did start, so the Carburetor should be fine.
My Dad does have a Honda pressure washer that was left in the basement for 4 years with fuel in the tank. When it was put in the basement, I did pour a few ounces of MMO into the carburetor opening, a few weeks ago it did start up, I did not think it was going to start up, it was like a miracle, yes, I had the water running out of the pressure washer while the engine ran. I ran the old gas out for like 20 minutes and then put in fresh gas with a bit of Mechanic In A Bottle!

I was going to mention MMO as an option in my original post but forgot. Also, I use Stabil Marine in my small engine fuel which has some PEA. Maybe I'll make a concauction of B12, MMO and a splash of Stabil Marine....

 

[Trav]

Berrymans Chemtool should work perfectly in that, that year carb used a soldered brass float not foam like on later models. There is nothing else that should be bothered by the Chemtool. The OE accelerator pump used a leather seal that is probably well dried out by now, put a kit in it, easy peasy.

 

[TacoFergie]

Berrymans Chemtool should work perfectly in that, that year carb used a soldered brass float not foam like on later models. There is nothing else that should be bothered by the Chemtool. The OE accelerator pump used a leather seal that is probably well dried out by now, put a kit in it, easy peasy.

I'll have to look into that. I've never been great at tuning a carb. I can take them apart and go back together no problem, but tuning has always baffled me. There's a few people I know that are good with tuning them though.