Tractorpoint Login

print < Tractorpoint Login

Search for =

Topic

Hi guys, a long stroke engine has a longer distance from the center of the crank to the center of the connection rod journal. This would give more torque to the crank for a given amount of pressure on piston crown. It kinda like using a cheater pipe on a breaker bar. Another point is that the pressure (psi) above the piston is not linear. This pressure, at full burn, is the highest when the volume above the piston is the smallest. As the piston descends and the burn area increases the psi per sq inch decreases as burn force is applied to a larger surface area. Gasoline has an expansion factor of about 4, that is 15psi compressed to 10 to 1= 150 psi at end of compression stroke. Light this off with the spark plug and will expand to a max of about 600psi and then begins to drop off as piston goes on down. The louder the exhaust the higher the more residual pressure left in the cyl is when the exhaust valve opens. This is why racing engines have a louder exhaust then basic work engines that are designed to get as much pressure per pound of fuel as possible applied to the piston instead of out the door. The downside of this, of course is reduce volumemetric efficiency. Peter, your description of the connection between volumemetric efficiency and torque was terrfic. Hope the above makes some sense.
regards,
george, keoke

Horse power to horse power
Operating and Attachments
Replies 24 Post by george pacheco

Hi guys, as far as I know all 6 volt Ford and Chy products were pos. grounded.
GM used neg grounds on their 6 volt cars. Ford and Chy switched to 12 volt in 1956 and went neg ground then. Chevy went 12 volts in 1955 (exception 6cyl corvette) and stayed neg ground. Chy went to alternators in 61, chevy in 63 and Ford used some in 63 and went full alt in 64.
It is ok to run a 6 volt starter on 12 volts for short burst's, keep in mind that the amperage draw will be higher and the engine will turn over faster.
When switching from pos to neg ground the amp meter and ignition coil leads need to be be reversed and the generator polarized to match battery polarity. Failing to repolarize will put the battery and generator in SERIES giving you 24 volts instead of 12. One advantage in going from 6 to 12 volts is that ALL of the OEM wiring is now of a heavier gauge (twice) of whats needed. An extreme rarity these days.

regards,
george, keoke

positive battery ground
Parts and Repair
Replies 19 Post by george pacheco

Murph, on some tractors,I think, if you close off the three point speed drop valve after the arms are down they wont be able to go back up until you open the valve back up. Shutting the valve off traps hyd oil in the lift cylinder.
regards,
george

down force device for 3-point
Operating and Attachments
Replies 9 Post by george pacheco

Here are the manul part #s for you John Deere 750 tractor.
Operators manual, omrw15455,
parts manual pc1873 (27JAN93)
tech manual, tm1242 (01SEP84)
Call JD publications at 1-800-522-7448
Good luck with your tractor.
regards,
george pacheco

SERVICE MANUEL
John Deere Tractors
Replies 4 Post by george pacheco

I am having a hard time getting a handle on this thread. As far as the top link on the hog goes, this is my take on it. If you have a cutter with NO short pivot arm on the tower then a CHAIN instead of a rigid center link would give you the flex needed between tractor & hog for uneven ground. However, there is no point in adding a chain to a cutter tower that already has a pivot arm since each would give the same flex noted above. The safety advantage (if any) of the pivot arm over the chain is that it would limit flip up towards tractor where as the chain would not. I agree with Murph that having the hog flip up all the way to the tractor, while not impossible, would be highly unlikely. Hope this post doesn't add to the confusion.

My Cutter Ain t Level
Mowers Field and Finish
Replies 53 Post by george pacheco

You can back drag if you pin or tie the moldboard in the up position.
Some box scrapers have a setup to pin moldboard in either position built on. It also helps if you tilt the box scraper slightly up in the rear when draggin backwards.

Hinged or fixed rear moldboard for box scraper
Operating and Attachments
Replies 3 Post by george pacheco

I have a Woods/Dual 3pt trencher with a hydraulic motor that turns the trencher wheels with the tractor in neutral. This moves both the trencher and tractor at the desired trencher speed. It also has a hydraulic ram that shifts the weight from the rear tractor wheels to the trencher wheels for traction. Ram can lift the tractor off the ground. Hydraulic motor speed can be set to be as slow as you want. This hydro drive trencher up can be effectively used on manual shift or hydro tractors. Chain runs off pto and cutting width is adjustable. These trenchers were original made the Dual company which I think is now owned by Woods. Maybe some body out there knows whether these units are still being made by Woods/Dual.

3 point trencher
Operating and Attachments
Replies 8 Post by george pacheco

Hi Roger,

I am interested in building a bucket tooth bar such as yours. Could you give me a rough idea on how you did yours. I have my own welding equiptment.

Thanks,
george

Loader Tooth Bar
Other Tractor Brands
Replies 9 Post by george pacheco

Chris,
Your may want to look at a Bradco 408 hoe. The specs on this hoe come in between the Woods 7500 and 9000. I have a 408 on my JD 970 and it uses the same factory JD frame mount used for thier own JD hoe. This makes for a quick on and off and is a very clean setup. Bradco hoes are more expensive then either Woods or Kelley but are built to comerical standards. When you see one you will quickly see where the extra bucks went. Also, go to the "tractor bye net board" and check out Mark's post on "back hoe specs" for a quick, all one page, comparsion of the different hoes. Bradco is on the web at, http://scat.com

Backhoe for the 4600 JD
Loaders Back Hoes
Replies 13 Post by george pacheco