kwanjangnihm wrote:Whats the horsepower & max rpm on the NOS 4a084 engine?
40-50hp at Sea Level depending on how how set it up I was told but more to the 50 mark I guess if you use a Solex carb and a tuned exhaust.
Now the MFG/Military rate them at 20hp but that is a cruising altitude/up in the air. 3,600rpm all day long.
I don't know the exact number, but when stripped down, some are saying they weigh about 125lbs and with the right prop/reduction gear you can run dry w/two people.
I know a guy in MS that has two left )NOS) and they are $600.00/$250.00 shipping.
I also met a guy local who said he has some but I didn't ask the price.
You must use a good oil cooler (15 row) and I have some oil filter numbers from the other forum whereas you can add up to a 2qt oil filter for more volume and cooling.
This is quoted from the 084 experimenters Yahoo group.
The engines were tested at TEN thousand feet at 107 degrees that they were
tested at.
> > These engines were run at full load for one thousand five hundred
> > hours, and THEN dynoed to insure that they pulled the rated power at
> > those conditions.
> > AFTER the dyno test, they were taken apart, and the parts were
> > measured for wear. If the sample engines did not BOTH make the rated
> > power, AND pass the wear test, the ENTIRE shipment of engines was sent
> > back.
a. General.
Engine Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 41084-2, -3 and -4
Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4 cycle gasoline powered
Number of cylinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 4 (horizontally apposed)
Horse power rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 20 at 3600 r.p.m.
Fuel pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Diaphragm 3.0-4.5 psi outlet pressure
Air cleaner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dry models 4A084-2, -3 and -4
Spark plug . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Shielded
Gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28-.033 in. (.071-.083 cm)
Magneto contact
Gap, Fairbanks Morse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..015-.019 in. (.030-.48 cm)
Gap, Slick Aircraft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .008-.012 in. (.020-.030 cm)
Valve tappet clearance cold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..007-.009 in. (.017-.027 cm)
(Intake and exhaust)
Governor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Centrifugal
Oil capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 quarts (4 1/2 gts. with oil filter change)
Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 volts alternating current (ac)
Starter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 volts direct current (dc)
Regulator-Rectifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 28.5 ± .5 volts at 1.5 amps
Firing order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..1-4-2-3
b. Dimensions and Weight Models 4A084, -3 and -4.
Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 20 in. (50.8 cm)
Width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28.50 in. (72.4 cm)
Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 22.10 in. (56.13 cm)
Links:
http://miniairboatassoc.com/084/4A084a.pdf
http://miniairboatassoc.com/084/4A084b.pdf
http://miniairboatassoc.com/084/4A084c.pdf
