Massey 98 Detroit 3-71 Full Pull

[@jankotze1959]

Great great video, love the old 2 stroke Massey, it is a serious puller.

[@apismellifera1000]

I love the sound of a 2-stroke Detroit diesel

[@Rainhill1829]

Oh yes👌

[@coinucopia]

Love that sound!

[@fuzzwack1]

I could work all day in the field with that tractor!

[@jw4620]

Detroit 2-strokes! Turning fuel into smoke and noise for years!

[@Rainhill1829]

That's right.

[@om617yota8]

No better sound than a wound-out Detroit.

[@Romans--bo7br]

I agree with you, but if you think 17 or 1800 rpm is "wound-out" I wonder what you would say to a 12-71 (this is a 3-71N in this M-F tractor - same as the Oliver Super 99) that we turned at 4,000 - 4,200 rpm in the Lady Butterfly sled puller?!? I ran the V12's in my W900 Kenworths between 2000 and 2450 all day long and I set both of them up to a maximum of 2850 after I "built" them. Back in the 1970s I built a 3-71 for a friends Oliver Super 99 (same engine set-up as this M-F in this video) that he wanted to pull sanctioned legal weight sleds with, as well as some county fair type pulls... similar to this video, but more weight. I changed it to a 4 valve head, changed it over to turbocharged marine specs with the correct pistons, liners, cam, Valesco springs, I highly "modified" the blower to be used in conjunction with a High performance centrifugal blower, 7075 injectors, fully blue-printed & balanced the crankshaft, rods & pistons, a custom welded 3 into 1 short tube exhaust header & collector to the turbo and the governor set at 3050 no-load. It yielded 368hp under full load on the engine dyno at 2480 rpm, and ran very reliably for nearly five years of pulling, before he decided that he didn't want to pull any more (well... actually his wife decided!), because he was gone too much on the weekends, and they had a new baby in the family... he still has the tractor, and No.... it's Not for sale. : ) We had to get rid of the stock "dual" intake filters because they couldn't flow enough air volume, and went to a single Farr dry type housing and filtration taken from a late 1960s Brockway Semi truck that had an 8-71 Detroit in it before it was scrapped. Building Detroit Diesels, is like building small block Chevy's.... can get get Lots of power out of them, with the "right" parts and not a Lot of money (back then), and can spin them quite high due to less reciprocating mass (re: weight) compared to comparable displacement 4 cycles.... and still can, just need more money, these days.

[@Romans--bo7br]

Open that 3-71N Up.... what is the maximum on that tractor setup - 1800 rpms? Set it up to 2100/2150.... they need the revs to help hold the torque, longer because of the Very short "Usable" power stroke travel.... and Never let them just sit there and idle like that, the cylinder temps drop too much and they will "glaze" the liner walls... not good.

[@dougbauer891]

Was that swapped into the tractor? Or they actually came that way??

[@Rainhill1829]

Yes indeed, this tractor is bone stock, right down to the paint.

[@OldIron2188]

@@Rainhill1829 I did notice that the motor's blue and not gray, it's probably been replaced, but it's the same motor. Also i want a MF 98 SO BAD now.

[@ThePaulv12]

Announcer said they're supercharged but they're not. Detroit Uniflow Diesel 2 strokes are scavenged by Roots blower that is a direct pumping loss on the engine and adds no power, rather costs power and quite a lot of power too. This substantial parasitic drag from driving the blower as well as the air it pumps has to be paid for in higher fuel consumption. Blower pressure is ~ .5 psi required to scavenge exhaust from the cylinder. Residual combustion pressure clears most of the exhaust but the slight pressure is required to complete the process and doesn't add any performance. In the process of scavenging the the residual exhaust, the blower is filling the cylinder with fresh air. Since it is a Diesel then some of the blower air can be dumped into the exhaust to ensure complete scavenge without the penalty of having fuel vapor mixed with it. In Australia Chamberlain made a Super 70 and Super 90 (70hp & 90hp) starting in the 1950s with the 3-71 as OEM.

[@Rainhill1829]

Quite right, the principal of operation is very much the same for the much larger EMD two stroke diesels, the blowers where essentially for scavenging and little else. We often use the term supercharger disambiguously even though we are all aware it really does not provide much more than atmospheric overpressure, it just sounds really cool.

[@ThePaulv12]

Yep. Sorry for being a pedant. Mechanics are often like that.

[@Rainhill1829]

Not pedantic at all, you are well informed.

[@ThePaulv12]

@@Rainhill1829 I'm a bit of an EMD nut lol

[@TIMEtoRIDE900]

@@ThePaulv12 Sorry for calling you out 3 years later, but in a 4-stroke the whole engine would be doing the "blower's" work and scavenging on the exhaust stroke and pumping losses on the intake stroke as well. The Detroit gets it all done at the bottom of the power stroke real quick. The "power" comes from doubling the power strokes coming from that ton of iron. Too bad it's dirty for emissions.

[@ethanfitton6336]

Why are Detroit and diesel and petrol engines are the only ones to run away at full throttle.

[@TIMEtoRIDE900]

The diesel "run-away" is usually a bad turbo seal which sprays hot engine oil right into the motor, that has NO throttle blades-butterfly.