Ok I have a question. We just purchased a older truck with a Fisher 8 ft plow w/under hood hyro, when I lower the plow it never takes the slack off the lifting chain. My question is how do I relieve that tension. Thanks in advance
Hmmm... That's a good one. The weight of the plow is what lowers it, so once it hits the ground the ram stops going down, so this is where the chain should be? So if the contour of the ground you are plowing goes lower out front, the ram should go lower & the plow also. If this is not the case then the chain needs to be adjusted. I'll have to look at mine next time its hooked up. If it needs to be adjusted, just lower the plow onto blocks of some sort so that it is off the ground, then push the ram all the way down manually. At that point the chain will be loose and you can adjust it as necessary.
We adjust our fisher chains so that the triangle will be level when the plow is down on flat ground. That way like BRL mentions the plow will follow uneven ground contours.
To get the ram down all the way, leave the valve open or in the float mode, and push down manually on the triangle.
Dino's got it. Leave the control in "float", and push the triangle down. I usually stand on the top of the blade, and use my knee to push it down, it's not easy sometimes. If it has sat on the ground for a while, lift it up 1st, then lower it to push in piston, reduces the stiction on the seal.
If it will not go down when doing what they say then you may have a problem with the lift cylinder or valve. Try doing it with the engine off. The weight of the plow is heavy enought to bring it down but it should be able to move by being pushed down.
The recommended way, per Fisher, is that the A-frame should hit the stops 1/2 inch before the lift piston fully extends (am I explaining it right?) In other words the piston should not be fully extended with the blade all the way up as high as it will go. This will also eliminate any tendency for the blade to "bounce" over bumps. The triangular piece may or may not be level with the blade down, depending on height of truck, contour of ground, etc.
That is how we do them as well. With our Fords though we found that this did not leave enough slak for the plow to drop into lower areas or when coming over a crest. This is because the 350s sit high. We had to leave more length in the chain to allow it to drop.
Not trying to start another Ford/Chevy thing. Just stating my experience with my trucks and Fisher plows.
Wow I remeber chains..... and hyd. lines....and the ugly brushguard.... and the bumper sitting 10" out in front of my 78 chevy......... im sure glad the meyer is gone ( the chevy too for that matter) and i love the boss on my new dodge!
On our plow both ends of the chain go down to the A frame of the plow so the middle of the chain goes into the A frame of the hoist piston. When the piston is all the way up there is space between the plow and the stops. There have been times when making a pile I have gotten the plow stuck in the pile and the only way to get out is to push the piston down and readjust the chain to one side to get it to go all the way up to the stops so I could get out of the pile. You have to be careful when you do this because after you get out the plow might not go back to the ground to readjust the chain. I usually rest it half way up the pile or use the extra saftey chain to hold it up so I can readjust the chain to the proper position.