Starting fluid question

Hammermechanicman

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I have noticed that every time someone suggests using starting fluid as a troubleshooting tool people are quick to caution that they can "blow the head off" or "bend the connecting rod" or "bend the valves" or "blow it up". Over the last 50 years i have used starting fluid in literally many hundreds of engines. I use about a can every two months in the shop. I have never damaged any engine.

Starting fluid has less energy density than gasoline it just vaporizes much easier than gasoline so it makes it easier to start. You can flood an engine with starting fluid just like gasoline and it doesn't "blow up". Some say it will ruin 2 strokes by "blowing out seals" or "scoring cylinders" or "explode mufflers". My question is does anyone have first hand experience of starting fluid blowing up a gasoline engine? Not something on the internet or something their buddy told them or some other legend. Pics would be nice. Just asking. Not talking about diesel engines.
 

Scrubcadet10

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Nope, never seen one blow up.. but i just use flammable brake cleaner for starting fluid, so i don't have multiple cans, that can do the same thing, taking up space.
Project Farm guy ran a Quantum on it for 30 minutes.
 

StarTech

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I figure if an engine can't run what fuel it is intended to use there is a problem.

BTW some engines do get hooked on the starting fluid. I had a Ford diesel that so dependent on the starter fluid that I had to use it everytime you started the engine; finally blew the injector pump.

And surely don't want to run a two cycle very long at all on nothing but starter fluid.
 

hlw49

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I bought a mower from a guy who told me that over the winter it got water in the cylinder and froze and busted the head. Took the head off and the cylinder and head were clean, no rust. Next time I saw him he admitted to using starting fluid on it. Sure did bust the head.
 

bertsmobile1

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The problem with starting fluid which is usually Either is it is designed to start diesel engines
In a petrol engine it can and that is a CAN cause preignition which as we all know can blow a hole in a piston in a single cycle
It should not be a problem with side valve engines but can cause problems with higher compression OHV engines
And while it's specific energy is lower than modern fuels . you can shove a whole lot more in there .
If you toss the proverbial tea spoon of fuel down the plug hole then only a small amount will vapourise .
The rest will drizzle through the ring gap , get stuck around the rings and allow the engine to fire a couple of more times as it evaporates .
You only have to look at all of the brain dead idiots on you tube that pump 1/2 a can into the engine then wonder why it backfires and set the mower on fire
 

Hammermechanicman

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Not buying it. A "Some guy said" i have heard tons of stories but have never seen a first hand damaged engine
 

Hammermechanicman

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In a petrol engine it can and that is a CAN cause preignition which as we all know can blow a hole in a piston in a single cycle
It should not be a problem with side valve engines but can cause problems with higher compression OHV engines

No offense but "it can" but i have never seen it and i have used it in everything from a high compression 396 chevy V8 to a 25 cc string trimmer and everything in between.

Still looking for a FIRST HAND experience. This thread will probably trigger some folks. Sorry.
 
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