I know this is an old thread,but i wanted to chime in here on the gas vs diesel debate....I am a diesel fan for heavy equipment and trucks 3/4 ton and larger that run loaded and tow more than 50% of the time...but the gas vs diesel isnt always clear cut with small power equipment..
In the case of articulated Ventracs and Steiners,both machines are better off with LC gasoline engines.In both cases the diesel option will not last longer than the LC gas options,in fact they will not last nearly as long,they do not hold more oil,they hold the same amount,and in both cases the LC gas engines are more powerful,have more torque,much less vibration,and are much cheaper up front.
The reason the Ventrac gas engine (D950G) is rated for intermittent 30 degrees has nothing to do with the oil sump,as the diesel and gas are the exact same bottom end,and oil pump/pickup.It is just because the diesel has no carburator/float bowl. The gas engine under the most extreme situations can "burp" hiccup or even eventually stall because the machines on a steep angle,and the fuel in the carb is finding its level...the diesel has an injection pump that doesnt care what angle it operated on as long as the fuel pickup in the fuel tank doesnt suck air,it will inject fuel as designed.
First off I want to say that the 31HP Ventrac turbo diesel is a hunk of crap engine.This engine is also used in many zero turn mowers,chippers,and other applications.In every application,it fails to live up to the diesel engine standards of long life,and reliability.There is only one reason its used,it is the most compact diesel engine in the displacement range,and power range.But this comes at a price,reliability,it just isnt built heavy duty enough for industrial applications it was designed for.Its too bad this is the top option for Ventrac buyers,since it has several design flaws and fixing them voids the warranty with Briggs and Stratton.The breather is routed poorly,resulting in many hydrostatic lock issues immediately after an oil change.This bends a rod slightly and results in an engine miss/skip,and eventual failure if ignored.The oil feed to the turbo has a screen which clogs,and burns up the turbo.The turbo rarley lasts more than 800-1000hrs.These engines rarley see over 2000hrs,before throwing a rod,and they cost in excess of 5000.00.Parts are very hard to get and expensive.The heads frequently crack under 1000 hrs on the turbo model,epsecially if youve run it over 210 degrees at all.The non turbo engine (26.5) hp is much better,it doesnt have the head,hydrostat,turbo issues,but it still rarely makes over 3000hrs before catastrophic failure...the gas LC which is no longer made is the diesel engine,modified to burn gasoline,compression is lowered,an aluminum head is added with carb,and distributorless ignition is added.This is the same crank, block and oil pan as the diesel,with much lower compression,and associated engine stresses from the lack of high compression and constant diesel fuel knock...think about it,this gas engine is grossly overdesigned,which is why it is the one to have,will it use a little more fuel,yes it will,but the reliability is unmatched,15000hrs is nothing for one of these engines if properly maintained....they literally run forever.In addition,the usual diesel advantages are not present with these briggs diesels because diesels need to do 2 things to be more efficient and reliable than gas engines,they are more efficient by taking advantage of the additional btu's diesel fuel contains per gallon,combined with running at lower RPMS...using torque more than engine speed...the ventrac diesels need to spin 3600....so they dont take advantage of this,and they do not make more torque than the gas because they have the same bore/stroke as the gas engine,instead of a long stroke which gives a low speed torque advantage.Running a diesel at 3600 negates 90% of its advantage over a gas engine period...diesel flame fronts move much slower than gasoline,at high engine speeds the diesel fuel hasnt had time to transfer all its slow moving energy(this is where all the diesel torque comes from) to the piston before being expelled,this leads to high EGT'S and poor fuel efficiency,(think this may have something to do with cracked heads,and turbo failures?) All your heat is going out the exhaust.This is why Semi's run down the road with large, slow spinning inline 6 cylinders,they get the most energy out of every squirt of fuel shot into the cylinders,they are built with very heavy duty construction,and the last forever..IMO 3000RPM is about the max a diesel should run,continously in order to deliver a good balance of power,and economy.The reason you'll never see a 3000RPM engine in a Ventrac or steiner is the bigger diesels(Kubota D1105),Yanmar 3Tn82/84 for instance that make 28hp-30hp at 3000,do not fit in the ventrac or steiner,the length of the front end,lack of space for cooling fan/radiator means the engine cannot be over 15" long...and with the single pump design limitations,they need 3600RPM to get enough GPM and pressure from the small 15 series pumps....machines like the Steiner 230 have a large engine compartment,and only 2wd with less hydraulic demands,and the kubota d1105 engine is the diesel option,it is THE engine to have in a Steiner 230,if you were buying a 230,that would far and away be the best option,it is a powerhouse,will last forever,and will run a 72" deck at 10mph and not strain one bit,however when considering a 430 Steiner,things are different.
The Steiner 430 diesel engine is in the same boat as the Ventrac,as in it is not the best engine for most appications,it just has different issues,first off its way to small,and overrated,fooling consumers into thinking its powerful enough for the demands of hills,duals,and 72" decks,and it isnt. It is only 722 CC displacement with no turbo option,it makes 15hp at best,although its rated at 21.Unlike the larger 953 ventrac diesels it is a good engine,and is reliable,will last quite a long time,but because it is constantly being overworked,they rarely run past 2500hrs without needing a rebuild,they are just worn out from the high duty/load..The engine is a dissapointment in power for someone who just paid all that extra money over a 33 generac,30 kohler,or 25LC Kubota gas.This diesel also vibrates a lot,more than average,and this vibration shortens the life of many components on the machine itself,like the radiator,exhaust,wiring connections and harness,It shakes the machine to death basically a lot faster than the gas engines do....the gas version of the kubota is also a converted diesel,it runs much smoother,its very overbuilt,and will run forever,and makes substaintually more power than the diesel version for a lot less money....
Until manufacturers find ways to fit larger slower spinning diesels into there small power equipment,I will be sticking with the LC gas options or air cooled when better...Every situation in different,and before us consumers lay out our hard earned cash we need to gather as much information as possible on which engine options will fit our use best,instead of using the generic assumption that diesels always last longer,hold more oil,and make more torque.So before you buy take a look at exactly what your comparing,and what the high idle on the diesel option is,if its the same as the gas option,id look further,and make sure it will fit your needs,and give you the extra power,efficiency,service life,and reliability your paying an extra 3500.00 for......Sorry for the long post,just wanted to mention these things no ones brought up so far,and they are important factors to consider.
