BRANDON — Few people have ever thought of buying a beat-up 1988 JD 8820 at auction and fixing it up to Class 7 performance standards.
And it wasn’t what farmer and custom combiner Billy Prince of Deloraine, Man., had in mind when he bought the dirt-cheap Deere in 2008.
But it’s what he ended up doing.
Prince bought the 20-year-old combine when he was 13.
“It was pretty wore out. I ran it like it was for a year, then decided to put in some new parts,” Prince said.
By the time the 2009 harvest rolled around, he had installed a long list of new parts and had the old combine running better than new.
“I’ve got it now to where it has better performance than Class 7 combines around here, but it’s not quite up to Class 8 numbers yet.”
Prince has run up to six m.p.h. in 60-bushel wheat with a 930 straight cut header. He also runs six m.p.h. in 100 bu. oats. The 200 horsepower conventional combine burns only 100 gallons of fuel in a typical 12-hour day.
“I’ve also got a 10-year-old Cat 480 I bought for $75,000, but the 8820 puts more money in my pocket.”
The teenager said his investment in the 8820 is less and his hourly operating costs are a lot lower.
To run those speeds, he modified the header by installing different pulleys for higher r.p.m. He now runs a 36-foot MacDon header because he feels it’s essential to keep the combine full.
“Some people pick a certain speed for each crop and then stick to it year after year. But that’s all wrong. You should drive a combine according to percent of load. You’ve got to push it. You’ve got to keep it full to make it work right for you.”
Prince took the feeder house apart after his first harvest with
the worn out combine. It needed a new floor and chain.
“The old cylinder wasn’t completely wore out yet, but the concave had a big bow in it. So I put in a new cylinder, concave and beater from Precision Farm Parts. All that cost me $6,000.
“I went about 150 percent over speed on the beater. It’s actually 147 percent over speed right now. I wanted 152 percent, but that’s as close as I could get with available pulleys.
“I still run my beater gate. Most guys say you shouldn’t, but I think it’s necessary.”
He installed a TSR straw chopper for $4,000 and an Air Foil chaffer for $1,500.
“The Air Foil works well in small grains but it doesn’t really shine in corn.”
The first time in the field with his modified combine was a big disappointment.
“I installed the upgrade kit on the beater. I changed the drive pulleys, but nobody ever told me I also needed to change those little plastic pulleys that run the speedo.
“I was cutting 85 bu. rye at 20 percent moisture. We were really pushing to get this field done before the rain hit. I destroyed two main drive variable speed belts in just three hours because of wrong pulley sizes.”
Adjusting the modified combine was also an issue. A neighbour suggested he should start wide open and close down from that point as needed.
That’s more or less where Prince ended up in 2009, but he started with the crank at four, or 0.25 of an inch.
He kept cranking it open four or five turns at a time until he ran out of adjustment. Each time he opened it up, it seemed that more power became available and he was able to increase ground speed. The samples remained the same or improved with each few turns of the crank.
Eventually, he arrived at cleanout settings with two inches at the front and one inch at the back. He ran the cylinder as fast as he could without causing cracking.
“Since then, I’ve always run wide open in every crop. It only makes sense that if you make all those modifications for higher capacity, then you should run it for higher capacity.”
He said cylinder speed is the only change he makes going between wheat and canola. Wind is the only factor he controls when he runs the Air Foil chaffer in small grains.
He keeps the bottom sieve wide open.
Mike Ellingson, who runs Precision Farm Parts in Sherwood, North Dakota, said he was amazed by what he was hearing about how Prince was running the combine.
“I couldn’t quite believe it. When we started building this system, we had no idea it could be used like this.”
He suggested to other customers that they try the same strategy and they got similar results.
Ellingson said the secret is keeping the machine full.
“You do not want material against steel. Material will thresh itself if you can keep the pressure on. And it seems there’s less grain loss. Billy consistently reported four kernels per sq. foot once he got things running the way he wanted.”
Ellingson said Prince lengthened the original adjustment arms on the left and right sides to gain even more clearance.
“Now he can put his fist between the concave and the cylinder.”
Ellingson said the improved performance is because of two factors: more material in the machine and more space on the cylinder to allow for that flow.
“We call it cylinder stagger design or progressive design,” he said.
“It bites off little chunks at a time instead of negotiating a long bar. We run half the number of bars. The original cylinder has eight bars to the circle. We have four bars to the circle. That makes it easier for an increased volume of material to flow through. We have a full circle concave. Our staggered beater has progressive paddles and it needs to run faster.”
Precision also makes a kit for John Deere rotary combines. Once Ellingson realized that the system was working for his customers with con-v entional combines, Ellingson decided to call some of his rotary customers.
STS customers removed their original JD bars and installed the same bars Precision puts on the conventional cylinder. However, they use the same number of bars.
Sam Somerville in Eatonia, Sask., has used it on his Deere STS and got a 75 percent increase in capacity in his durum.
Somerville went from a three millimetre gap all the way to 22 mm and increased cylinder speed from 900 rpm to 950 r.p.m.
Increased ground speed was necessary to feed the machine, boosting it from 3.8 m.p.h. to four m.p.h. to a range of 6.8 to seven m.p.h.
Fuel consumption fell on a per hour basis after opening the machine up.
Ellingson said it’s hard to cut back on the number of bars on the STS rotor because it only has three, but he replaces the original five-inch bars with the same Precision bar design that Prince installed on his conventional combine.
“The factory Deere bar is designed for corn and beans,” Ellingson said.
“Billy borrowed an identical 8820 that had no modifications. He opened it up wide to see what would happen. It plugged solid in 150 feet. No factory stock threshing mechanism is designed for this high volume concept.”
Ellingson said combines are designed for material-to-steel contact. Material-to-material contact is gentler on the crop and requires less energy, but he cautioned that the big gap concept won’t work if you can’t keep the combine full and working hard.
“If you run big clearances and you can’t keep it full right up, then material will pass through without being threshed. That’s no good.
“I had a call from a customer in Kansas where they harvest a lot of terraces and washouts. He can only open up to 13 mm max because they have trouble keeping the combine full in those conditions.
“I don’t think you want to try this unless you’re in country where you can really stuff the combine full.”
Ellingson and Prince have plans for Prince’s more expensive Cat 480. Modifications are available to make the machine handle more straw.
“There are some new rotary separators that have a smaller tube with deeper blades,” Ellingson said.
“Billy thinks he wants the straw-pull on the separator to go faster so it moves more straw.
“It’s still in the planning stage, but I think we’ll install our Precision staggered cylinder like he used on his 8820 and upgrade the APS beater in front.”