New Holland 617 disc mower- problem

[rwk5412]

I bought a New Holland 617 new in 07, used it for 4 hay seasons (no hay last summer due to drought). I just serviced it this weekend and noticed the blades on the first two drums were nicking each other when they pass by each other in the front. The first two drums both spin clock wise, as such they already come close to hitting, but I don't think they've hit before.

So, I removed the first drum and noticed that it has been scrapping against the module on the sides. It's not seriously damaged, but that has to be a symptom of a problem. I pulled off some of the other drums and noticed that another one has been scraping as well.

What I ASSUME has happened is the bearings might be going out, but I don't really notice excess play in those drums when compared to other ones that haven't been scraping against the rim of the module.

Another thing I noticed when changing the oil was the gear box and the module drive box were both dry. I filled both up and oil starting draining out of the breather screw, so I went ahead and replaced both breather screws. Oil still came out of the gear box breather but not nearly as much. 2 oz's probably came out of the gearbox after a couple hours of operation, that's manageable. Is that normal operation? I flushed both gear boxes twice, the main gear box oil looked fine but both times I flushed the module drive box the oil came out looking like muddy water or chocolate milk.

So, any thoughts?

Edit: FYI, I haven't been the one using it, it's been on the parents ranch and whoever they have that's been using it has also been servicing it, just not doing a good job.

 

[Bigfoot62]

I'm not familiar with that exact model, but I have two disc mowers and have been around them (and operated them) for years.

Yes, you do have a problem. The gear timing is off if the blades are hitting each other. It's very likely that you have damaged gears in the cutter-bar. You will need a good service manual, or you'll have to take it to a dealer to get it fixed.

For future reference, the cutter-bar is not supposed to be full of gear oil. It should have a drain hole and a fill hole. Same for the gearbox.

 

[rwk5412]

I'm not familiar with that exact model, but I have two disc mowers and have been around them (and operated them) for years.

Yes, you do have a problem. The gear timing is off if the blades are hitting each other. It's very likely that you have damaged gears in the cutter-bar. You will need a good service manual, or you'll have to take it to a dealer to get it fixed.

For future reference, the cutter-bar is not supposed to be full of gear oil. It should have a drain hole and a fill hole. Same for the gearbox.

Well, the first two modules both spin CW, so they pass very close to each other no matter what, but they now hit each other probably once every 400 revolutions or so.

As far as the oil is concerned, each module on the bar is supposed to be filled with 10oz of 80W90, the drive module 10oz of 80W90, and the gear box 37oz of 80W90. All the modules on the bar were fine, I drained them using the drain plug and refilled using the fill plug. The drive module and the main gear box were both empty, I pulled the drain plug and nothing but a drip came out. I ran a little oil through them both and it came out of the drain hole, so they were simply empty.

The weird thing about the blades nicking each other though, like I said above is that they only hit (the first two modules only because they both spin the same direction) about once every few hundred RPM's. I even cut with it for about an hour and the damage on the very end of the blade on the corner was minimal.

I do have the repair manual, maybe I will take the two modules off the cutter and take them to the shop to have someone go over them. Any other thoughts?

 

[banjodunn]

G'day it is possible that the timing is off as stated but you may also have worn driveshaft between the modules. Do the plates sit at 90deg to each other? If not then the g/box may have been of at some time and not timed correctly, if you hold the first g/box and turn the next one do you get alot of play? This may indicate worn d/shaft


Jon

 

[rwk5412]

The play between the two modules seems to be minimal, but enough to make it where the blades get close enough to hit when they pass by each other. Since these two modules spin the same direction and are module 1 and 2 (side by side), the only way they work is by getting close to each other. HOWEVER, they ONLY hit when they pass each other on the front side of the bar, not the back, so it does lead me to believe it's a timing issue. On the back side of the bar they don't get nearly as close to each other.

I am thinking someone screwed around with one of the first two modules at some point in time over the past year or two. I wasn't operating or maintaining it during that time, some employees were. I will have to take a look at it next weekend or the following weekend (I downloaded the repair manual) and check the timing on the first two modules as well as the shaft between them if I can.

Thanks for the input from both of you, if anyone else has any experience with this please feel free to chime in.

 

[banjodunn]

G'day just another thought the driveshaft between the first two modules may be twisted, this would explain timing issue in those two discs only


Jon