Convert GAS Briggs V-Twin to DIESEL?

Skippydiesel

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I am a fan of propane as autogas fuel. Curious about your oil change interval statement, if it comes out looking clean and not smelling burnt (assumption). How are you know the oil needs changed at same intervals? Is there any data from oil sample tests (Blackstone Labs, or similar) that prove out the same oil change interval is true for gasoline and propane fuels? I am of the understanding propane burns cleaner, I would think that the oil would contaminate more slowly. Does the oil just wear out at a certain rate with no other factors?
I am but an old farmer, limited understanding, just accept the recommendations of what seems rational.

Modern crankcase oils containe many additives, to help them performer to the standards the engineers/chemists demand.

When the oil is fresh, the mix is in balance & contains no foreign contaminants.

Subject the oil to;
  • Heating & cooling cycles
  • Byproducts of combustion
  • Unburnt fuel
  • Moisture
  • Pressure
  • Oxidisation
  • Metal particles in suspension
  • Atmospheric dust
  • ?
and the additives start to be consumed, overwhelmed and out of balance.

The oils ability to keep metal components apart will be reduced. Eventually the engine will experince accelerated wear.

My understanding is that used oil can be recycled, that is cleaned, new additives mixed and the oil can be used again.

It seems to me that no matter the fuel type, burnt in the engine, at some stage the crankcase oil should be replaced, no matter how clean/dirty it may look. :devilish:
 

SamB

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Alright, I'm gonna cut the chit chat and get to the question: COULD I convert my Briggs and Stratton V-Twin (445677) to use Diesel Fuel? It seems feasible to me. Would the oem carburetor work, or would I have to somehow make it fuel-injected? I think that if I replace the spark plugs with glow plugs, maybe get oversize rings or something else to increase the compression, and probably mess with the timing a bit, it should run. Any Ideas? Any diesel techs out there? I would probably have to get billet rods too. TIA
After a bit of consideration and thought, I have to ask, what is your end result wish? Do you want to convert a B&S einge to diesel or convert your mower to diesel power? If it's the latter, a number of APU units on road tractors(power units) have air cooled Hatz diesel engines on them. While the majority APU's are water-cooled, the Hatz engines are very reliable(German-built) and very long lasting.
Repowering an expensive ZTR that has a bad engine but is in otherwise great shape would be a canidate for just such a repower.
On the other hand, converting the B&S engine itself to diesel,give it a shot and keep us posted.
 

Craftsman Garage

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Simple answer is no.
The compression is too high for a standard gas engine to be converted to diesel then there is the following.
You will need a custom cylinder head with precombustion chamber, glow plugs, fuel injectors with heat shields and an injection pump that is able to properly supply adequate high fuel pressure to the injector of several thousand psi and then time it all to work with either gear drive to the crank or roller chain.
Diesel engines do not use carburetors they use a high pressure injection pump, the good diesels like cummins use mechanical pumps.
Then the internals, beefed up crank shaft, bearings, rods, piston and rings.
Look back to GM's flop of the early diesel conversions, bent connecting rods, broken rings, blown head gaskets. Not that the duratrash from Isuzu is much better.
I love the 12v 5.9 Cummins :D
 
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Craftsman Garage

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Don't think it is possible. Not enough compression, the block is not strong enough to handle the compression increase, the rods are too weak, no way to put injectors in the head.
As for a turbo many farm tractors have not used a turbo the AC D19 was the first, then other manufacturers started using them. There was a company M&W that made kits to put them on nonturbo engines. Some successful and some not. If memory is right the 4320 was JD first attempt. Many early farm tractors were not turboed and ran and worked just fine. That said some farmers installed turbos and turned down the fuel to get original HP they did it for better fuek efficency.
If you wanted to try anything it would be easier to convert it to ALL FUEL. These used "tractor fuel often refered to as distolate" You need two fuel tanks a small tank for gasoline for starting and a large tank for fuel. Start on gas warm up switch to fuel, to shut off switch back to gas so it will start next time. The problem with tractor fuel is there is a substantial power loss.

Forgot Briggs did has a three cylinder diesel made by Dihatsu and Toyota They have been out of production for many years because of many issues.
I was thinking I could put injectors in the manifold
 

Craftsman Garage

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After a bit of consideration and thought, I have to ask, what is your end result wish? Do you want to convert a B&S einge to diesel or convert your mower to diesel power? If it's the latter, a number of APU units on road tractors(power units) have air cooled Hatz diesel engines on them. While the majority APU's are water-cooled, the Hatz engines are very reliable(German-built) and very long lasting.
Repowering an expensive ZTR that has a bad engine but is in otherwise great shape would be a canidate for just such a repower.
On the other hand, converting the B&S engine itself to diesel,give it a shot and keep us posted.
I wanted to CONVERT A BRIGGS TO DIESEL. I know I can just buy a Diesel engine, but I like a challenge. And remember the only dumb question is one you're too afraid to ask :)
 

slomo

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Riders and 0-turns are already excessively heavy that they all, rut the turf badly. Soil compaction to the max. I typically push mow all the time. When I break out the rider just to use her, I can tell the ground is more compacted after one rider mow. And I have a Snapper rear engine rider that weighs a lot less than some 0-turn.

So knowing soil compaction is a problem, adding a way heavier Diesel motor is not helping anything. Course a lot of you have pasture grass and don't care. It's your money and grass.
 

Skippydiesel

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Slomo - don't know what the climate/soil conditions are where you mow but feel compelled to make some helpful (?) suggestions:

Only mow ;
  • When grass is dry
  • Soil in relativly dry
  • Avoid using same tracks - change mowing pattern

If living in a high rainfall area and or clay soils;
  • Put in some ag drains
  • Aerate soil
  • Apply liberal amount of lime or gypsum to improve soil permeability :devilish:
 
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