Convert GAS Briggs V-Twin to DIESEL?

[grumpyunk]

The increased purchase price of diesel engines in pickup trucks made them uneconomical unless the miles driven annually were high. Those who bought thinking they were going to save money may have realized the increased investment had a pretty long payback time before actually costing less than a gas burner.
I have nothing against diesel engines, but note that they were not as popular to buyers as the major pickup sellers found out.
I am referring to the smallish ~3.0l engines that were available, not the 6l+ size.
As far as doing a diesel conversion, it would likely prove to be a unsuccessful endeavor as the engine likely would not handle the increased compression and running pressures if they could be engineered in somehow, and design and installation of some sort of injection system would be difficult to say the least.
There are some horizontal shaft smallish singles from China that make a lot of noise and smoke, and will shake most equipment apart unless everything is Loctited that might be interesting to the poster for not a lot of money. They appear to be based on the Honda single clones with a lot of extra metal in the head/cylinder/block/piston/rod/crank to handle the increased pressures needed to operate as a diesel.
Might be a good fit for the 'mud motors' that hang off the stern of boats used mostly in shallow water. Lots of torque at low rpm is perhaps a good fit for a boat propeller.
tom

 

[Skippydiesel]

The increased purchase price of diesel engines in pickup trucks made them uneconomical unless the miles driven annually were high. Those who bought thinking they were going to save money may have realized the increased investment had a pretty long payback time before actually costing less than a gas burner.
I have nothing against diesel engines, but note that they were not as popular to buyers as the major pickup sellers found out.
I am referring to the smallish ~3.0l engines that were available, not the 6l+ size.
As far as doing a diesel conversion, it would likely prove to be a unsuccessful endeavor as the engine likely would not handle the increased compression and running pressures if they could be engineered in somehow, and design and installation of some sort of injection system would be difficult to say the least.
There are some horizontal shaft smallish singles from China that make a lot of noise and smoke, and will shake most equipment apart unless everything is Loctited that might be interesting to the poster for not a lot of money. They appear to be based on the Honda single clones with a lot of extra metal in the head/cylinder/block/piston/rod/crank to handle the increased pressures needed to operate as a diesel.
Might be a good fit for the 'mud motors' that hang off the stern of boats used mostly in shallow water. Lots of torque at low rpm is perhaps a good fit for a boat propeller.
tom

Try to remember - the USA is NOT the centre of the known universe.
In my part of the World turbo diesel vehicles from around 1.6 - 3.5L are very popular and have been so for very many years.
Light commercials (2.2 - 3.5L Ford, Issuzu, Toyota, Mazda, VW, MB, Nissan, Mitsubishi, Photon, LDV, etc) are amongst the best selling vehicles of all.
American (Ford Chev & Dodge) petrol powered, big utes, have recently become trendy. Their appalling fuel economy is already impacting negatively on their resale value.

 

[StarTech]

Here is an example of a purpose built diesel engine that can be reasonably priced.


And here is IPL of one version of this engine so you can what is involved.

http://sklep.yanmar.pl/usr/o/2v750-cvdi_1_.pdf

 

[grumpyunk]

Try to remember - the USA is NOT the centre of the known universe.
In my part of the World turbo diesel vehicles from around 1.6 - 3.5L are very popular and have been so for very many years.
Light commercials (2.2 - 3.5L Ford, Issuzu, Toyota, Mazda, VW, MB, Nissan, Mitsubishi, Photon, LDV, etc) are amongst the best selling vehicles of all.
American (Ford Chev & Dodge) petrol powered, big utes, have recently become trendy. Their appalling fuel economy is already impacting negatively on their resale value.

Obviously my comment was directed at the US market for pickup trucks. The premium paid for better fuel economy and low end torque, especially useful for towing, extends the payback time such that most original purchasers will have sold the vehicle long before.
I realize that many countries use diesel engines in their fleets of cars. The governments tax structures make them attractive.
Diesels in small power equipment parallel the pickup truck scenario in that the increased purchase price for a diesel and the scarcity of such models make their market presence minimal. Most small diesels vibrate a lot more it seems, and outdoor power equipment has enough vibration already without adding that of a small diesel.
One that is used commercially may pay for itself, but again, there are not a lot to choose from.
tom

 

[Skippydiesel]

Obviously my comment was directed at the US market for pickup trucks. The premium paid for better fuel economy and low end torque, especially useful for towing, extends the payback time such that most original purchasers will have sold the vehicle long before.
I realize that many countries use diesel engines in their fleets of cars. The governments tax structures make them attractive.
Diesels in small power equipment parallel the pickup truck scenario in that the increased purchase price for a diesel and the scarcity of such models make their market presence minimal. Most small diesels vibrate a lot more it seems, and outdoor power equipment has enough vibration already without adding that of a small diesel.
One that is used commercially may pay for itself, but again, there are not a lot to choose from.
tom

In Australia,
The vast majority of contract/local government, grass cutting, is done using diesel powered mowers (most over 25 hp).
Emergency & remote power supply electricity generators, over about 7 Kw, are diesel
Dedicated fire fighting pumps are for the most part diesel (being less flammable than petrol)
All self propelled agricultural equipment is diesel
Where electricity is unavailable, large pumps are diesel
Work boats are often diesel, being less prone to on board fires
All trucks, 2 tonne upwards, are diesel
The list goes on & on

"The governments tax structures make them attractive."

You may be correct - I understand that petrol is cheap in the US.
For us, diesel power represents economy of operation , which for commercial operators includes, low fuel consumption, longevity & reliability.

"Most small diesels vibrate a lot more"

All single cylinder engines vibrate a lot, multi cylinders less so.
Vibration is a factor of balance or lack thereof.
How an engine in mounted, what & how its coupled to, will also influence is tendency or not to vibrate and how that vibration is mitigated.
My wife drives a Hyundai i30, 1.6L, 4 cylinder, turbo diesel. My son uses a Hyundai i30, 2L, 4 cylinder, petrol, to commute. The diesel is far smoother, quieter, more torque, less rapid acceleration, about 1/2 the fuel consumption, than the 2L
I drive a Ford Ranger, 3.2L, 5 cylinder, turbo diesel. I do a lot of towing. You would be hard put to fine a smoother running engine.

 

[hlw49]

[Hot Item] 25HP Air-Cooled Twin Cylinder Vertical Shaft Diesel Engine

Model NO.: R2V870V Ignition Mode: Electric Ignition Speed: High Speed Cooling Cylinder: Air-Cooled Intake Pressure Impulse: Naturally Aspirated Piston Movement: Reciprocating

www.made-in-china.com

 

[Skippydiesel]

[Hot Item] 25HP Air-Cooled Twin Cylinder Vertical Shaft Diesel Engine

Model NO.: R2V870V Ignition Mode: Electric Ignition Speed: High Speed Cooling Cylinder: Air-Cooled Intake Pressure Impulse: Naturally Aspirated Piston Movement: Reciprocating

www.made-in-china.com

Sounds the goods BUT the specifications are a bit suss - "Ignition Mode - Electric Ignition" something lost in translation?

Personally I would prefer liquid cooled for best performance, longevity and possibly quieter running.

 

[David40]

Would never handle the pressure and explode.

 

[Kiss4aFrog]

This is two pages longer than it needs to be. With enough money you can do anything. Diesel would need to be injected. Glow plugs are just to get it started and would burn out if needed to keep running. You'd need a custom crankshaft, cam, rods and pistons.
Way less work and $$$ to just buy a diesel. Even less to get a replacement Briggs if yours is old and tired.

 

[rswapp]

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

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.