billyO Posted July 27, 2013 Share Posted July 27, 2013 Hello all. Now that I've got my generator/welder running, an OLD Marquette AC stick welder/220 generator with an Onan engine, on the fuel tank is a big sticker that says, LEADED GAS ONLY. Do I need to worry about this, and if so what type of additive do I need to look for? thanks Quote Link to comment Share on other sites More sharing options...
jmccustomknives Posted July 27, 2013 Share Posted July 27, 2013 You should be able to purchase "lead" fuel addatives from your local parts house. The lead in the fuel acted as a lubricant for the valves. If you can find alcohol free fuel use it. The alcohol in fuel these days will eat up the seals and hoses and make a mess of your motor. Since Onan is out of buisness finding parts is a nightmare so take care of it. Quote Link to comment Share on other sites More sharing options...
Neil Blythin Posted July 27, 2013 Share Posted July 27, 2013 Aviation fuel (AvGas) is still leaded, and is also alcohol free. Quote Link to comment Share on other sites More sharing options...
ianinsa Posted July 27, 2013 Share Posted July 27, 2013 Aviation fuel (AvGas) is still leaded, and is also alcohol free. I thought Avgas was "near asXXXXXXXXX " Parafin(kerosene? similar to diesel) not petrol(gasolene) but then I'm no expert. Too many of your posts need editing for language, watch it, next time a 10 day BAN may be in order to get you to pay attention. Quote Link to comment Share on other sites More sharing options...
Neil Blythin Posted July 27, 2013 Share Posted July 27, 2013 Jet fuel is essentially kerosene. AvGas is gasoline. Many older general aviation aircraft (the cessna & piper aircraft built in the 50's - 70's) these days are running automotive gasoline (which they call 'MoGas'), as the grade of AvGas they were designed to run on is no longer readily available. Those older aircraft engines were designed to run an avgas grade called 80/87 (between 80 to 87 octane, leaded gas), which is no longer produced. The 'common' grade of avgas is called 100LL (100 octane, low lead); which is actually a bit too high of an octane to make those old engines happy. But, they are happier on that than on lead-free mogas, which is closer to the octane rating they like. The happy medium is running a tank of 100LL through every once and a while (for the lead content) and running on mogas the rest of the time. If you have a general aviation airport near by, stop in at the local flying club and have a chat with them. Pilots take a small fuel sample from each tank every day the aircraft is operated (to check the fuel for water contamination). This sample then needs to be dumped. Usually, there is a fuel can in the corner of the hangar for collecting fuel samples. If you're just looking for some leaded gas for an old machine engine, you can probably arrange to empty the fuel sample can every so often for free. This saves them the hassle of having to properly dispose of it. Mix it in with a little regular gasoline, and you'll end up with a mid-grade fuel with some lead in it. Quote Link to comment Share on other sites More sharing options...
ianinsa Posted July 27, 2013 Share Posted July 27, 2013 Thanks for that now I'm much more enlightened! Quote Link to comment Share on other sites More sharing options...
jmccustomknives Posted July 27, 2013 Share Posted July 27, 2013 If you've got a local drag strip that's where you will most readily find Av gas. We have a few stations around here that offer alcohol free fuel. It's about 10cents more than regular. Av fuel is, well you better have deep pockets. With it's higher octain, I'm not sure how well that low compression Onan will run on it. Quote Link to comment Share on other sites More sharing options...
Yetti Posted July 27, 2013 Share Posted July 27, 2013 I think you will find most engine oils are now designed to deal with the lack of lead in fuel. mostly the rings needed it for seating properly and the valves needed it for lubrication to prevent guide wear. if you are using any oil on the market today that is designed for auto use it will work in your engine without the leaded fuel. Quote Link to comment Share on other sites More sharing options...
yahoo2 Posted July 29, 2013 Share Posted July 29, 2013 leaded vs unleaded onan pdf service bulletin from 1975 Quote Link to comment Share on other sites More sharing options...
BIGGUNDOCTOR Posted July 29, 2013 Share Posted July 29, 2013 I wouldn't worry about it myself. I know lots of old muscle cars running around with unleaded in the tanks,and no additives, without any issues. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.