Hack: Filtering exhaust smoke
 

Continued from https://www.gassavers.org/showthread.php?t=10801

My Craftsman lawn tractor's Briggs & Stratton 15hp engine smokes. I finally gave up and brought it to a repair shop. Their professional opinion is that it can't be repaired for less than replacing the engine.

Since it's a lost cause anyway...

• What if I just filter the smoke and keep running it until it seizes? I can't think of any reason not to.
• Can anyone think of a way for me to filter the smoke out of the exhaust?
• Would a diesel particulate filter clean up the gas engine's smoke?
• Is there such a thing as a cheap small DPF (probably for small diesel engines)?

It's burning oil right?

I don't remember the ratio we used but I had a buddy whose tractor smoked pretty bad and we were able to help it some by taking a thick oil like 20w50 and thinning it out with some 2-stroke ashless oil.

I don't know what's producing the smoke, it's white or grey. I'll try to get that info when I go to pick it up from the shop.

Coffee can + mineral wool insulation.

Where would I get mineral wool insulation? Google tells me it ought to be worth a try, but the only place I can remember seeing it is in large home appliances.

Come on Man, are you serious? Sounds like a waste of time.

If that is oil smoke, which it sounds like, then it's shot. You can have it bored out, put an oversize piston and rings in (probably valves and guides too), and so on, or use it until it physically doesn't run anymore, or junk it.

There are ways around shelling out the big bucks for a new engine. For example, I wrecked the 11HP B&S on a riding mower not too long ago. I hit the scrap yards and found a John Deere rider ready for crushing, that had an 11HP B&S in it, but it was stripped of it's carb and some other stuff. So what! My old engine has them! I got it for FREE and was VERY pleasantly surprised to find that long block to be a VERY low-hour block as the cylinder looked like new! Put it all together and that rider is now better than it has ever been in my ownership. Cost? I spent about $7 on gaskets.

If you have a trade school nearby that does automotive machining they might bore it out for you. I've had that done in the past too. Then all you're stuck with is the cost of parts.

Or there is scrounging around for a complete replacement engine. If you put yourself in the right place at the right time, they are free or nearly so.

as always clencher, you are supremely resourceful.

i wonder if a wet wash rag would filter the smoke in the mean time. i'd ride w/ a bucket of water as well, just in case! :eek:

OK if you're going to screw around, run the exhaust pipe down into the pail of water and make your own little fake "outboard and lake" exhaust.

Sounds like the corpulent fraulein might be doing her solo right about now for your engine. If you're going to need a new engine soonish anyway, I wouldn't bother nursing this one, unless you expect to come across a deal on one given more time.

How about running 90weight gear oil in the crankcase- I know someone who ran chainsaw bar oil and said it reduced smoking.