Fecon Hydraulic drive motor spline

APSmulching · Apr 7, 2015

I started doing some work to my bh85 this weekend and had a hard time removing one of the hydraulic drive motors. It was seized, so I have to remove it with the spindle shaft on it. With some heat and a hammer I got it apart and found that the splines were really worn out. Especially on the one that was seized. So I need to replace the spindle shafts with the female spline and the spline output shaft on the Rexroth motors(1-3/8 - 21 tooth)
Those splines have a lot of stress on them and I have put a thick moly grease on them but when ever I check them after about 500 hours they are dry. Has anyone had any luck using another type of lube there?

oldnslo · Apr 7, 2015

Castrol Optimoly Paste White T

It won't completely stop the fretting and corrosion but it will sure slow it down.

APSmulching · Apr 7, 2015

I was told that DuPont Krytox may be good for splines also. I want to use something that will help the spline to last longer. Im getting prices for new shafts for the Rexroth motors and my first price is 1600. each. That's a lot more than I expected

oldnslo · Apr 7, 2015

APS,
I believe on the Rexroth A2FM bent axis motors that the shaft includes the complete rotating group so that would explain the $1600 each. You may want to ask your parts supplier to confirm this.

SKIDPLATE · Apr 8, 2015

APSmulching said:
I started doing some work to my bh85 this weekend and had a hard time removing one of the hydraulic drive motors. It was seized, so I have to remove it with the spindle shaft on it. With some heat and a hammer I got it apart and found that the splines were really worn out. Especially on the one that was seized. So I need to replace the spindle shafts with the female spline and the spline output shaft on the Rexroth motors(1-3/8 - 21 tooth)
Those splines have a lot of stress on them and I have put a thick moly grease on them but when ever I check them after about 500 hours they are dry. Has anyone had any luck using another type of lube there?

View attachment 419988

Hi, I'm the Service Manager for FECON for future tech support or service needs please call 800-528-3113. We use anti-seize to prevent corrosion on the two spline shafts. This should solve your issue,

Thanks,

APSmulching · Apr 8, 2015

SKIDPLATE said:
Hi, I'm the Service Manager for FECON for future tech support or service needs please call 800-528-3113. We use anti-seize to prevent corrosion on the two spline shafts. This should solve your issue, Thanks,

Thanks Skidplate, what kind of anti-seize do you recommend? They make a lot of different types now. The new Fecon shafts with the female spline look like they have a little copper anti-seize on the splines.

SKIDPLATE · Apr 8, 2015

That's it the copper base anti-seize. A light coat on the male and female splines.

tonyoz · Apr 8, 2015

You can buy the female spline end as a replacement part, cut the old one off and weld the new one on. Much cheaper than buying a new shaft unless you want a spare. When you replace the shaft on the motor the rotating group and bearings have to be replaced as well so you end up with a fully reconed motor at about half the price of a new one. Its been suggested to me that I drill a hole through the spindle shaft and fit a grease zerk in the bolt hole where the pulley sits and give it a pump of grease every so often. Got to better than pulling motors off especially when you're busy.

APSmulching · Apr 8, 2015

tonyoz said:
You can buy the female spline end as a replacement part, cut the old one off and weld the new one on. Much cheaper than buying a new shaft unless you want a spare. When you replace the shaft on the motor the rotating group and bearings have to be replaced as well so you end up with a fully reconed motor at about half the price of a new one. Its been suggested to me that I drill a hole through the spindle shaft and fit a grease zerk in the bolt hole where the pulley sits and give it a pump of grease every so often. Got to better than pulling motors off especially when you're busy.

Hey Tony, I knew you would chime in. You have been through it all. I thought about reworking the spindle shafts with a new female spline but called and found out they were not that expensive. He also mentioned the new shafts are one piece now and not welded.
I also talked to an engineer from Loctite and they said that the best way to stop spline wear is to bond them together with cylindrical lock, like #680. You just won't be able to pull a motor without the shaft coming with it. I just did it with the one that was seized so it's not too bad of a job. With a little heat the loctite will soften up to remove it. To replace the motor splines with parts and labor is coming in at almost 2000.00 each.

tonyoz · Apr 9, 2015

The last shaft I purchased was AU$1100, the billet end was AU$85 plus fitting so for me it's worthwhile as long as the shaft is ok where the bearings run. A good bloke with a lathe and welder can knock the job over in a couple of hours.

APSmulching · Apr 9, 2015

tonyoz said:
The last shaft I purchased was AU$1100, the billet end was AU$85 plus fitting so for me it's worthwhile as long as the shaft is ok where the bearings run. A good bloke with a lathe and welder can knock the job over in a couple of hours.

Wow, those shafts are 200.00 here.

tonyoz · Apr 9, 2015

APSmulching said:
Wow, those shafts are 200.00 here.

Gees I must have CRAFT. $1100 a pair, $550 each.

APSmulching · Apr 9, 2015

tonyoz said:
Gees I must have CRAFT. $1100 a pair, $550 each.

Well your probably charging 3-4,000 per day down there because of your inflated overhead

tonyoz · Apr 9, 2015

APSmulching said:
Well your probably charging 3-4,000 per day down there because of your inflated overhead

Yeah right, I wish

t320pilot · Apr 10, 2015

What year is your bh85? Mine came from the factory with a grease fitting that I give 1 or 2 pumps of grease every 40 hrs.

APSmulching said:
I started doing some work to my bh85 this weekend and had a hard time removing one of the hydraulic drive motors. It was seized, so I have to remove it with the spindle shaft on it. With some heat and a hammer I got it apart and found that the splines were really worn out. Especially on the one that was seized. So I need to replace the spindle shafts with the female spline and the spline output shaft on the Rexroth motors(1-3/8 - 21 tooth)
Those splines have a lot of stress on them and I have put a thick moly grease on them but when ever I check them after about 500 hours they are dry. Has anyone had any luck using another type of lube there?

View attachment 419988

APSmulching · Apr 10, 2015

t320pilot said:
What year is your bh85? Mine came from the factory with a grease fitting that I give 1 or 2 pumps of grease every 40 hrs.

Mine was built in 2007. Are you talking about the grease fitting that's on the spindle housing? That one only lubricates the bearings not the spline.

t320pilot · Apr 10, 2015

Oh, ok I see it is for the bearings only. Maybe I should take a look at mine too? Did yours make a grinding sound or did you just randomly decide to inspect it?

APSmulching · Apr 10, 2015

t320pilot said:
Oh, ok I see it is for the bearings only. Maybe I should take a look at mine too? Did yours make a grinding sound or did you just randomly decide to inspect it?

I checked them last year and saw that one side had about 50% wear on the spline. The other side was seized. So I pitot back together because I was too busy to deal with it. You should definitely check your out. Once either side spins the spline your done. The other thing you should check is the grooves in your pulleys. When they wear out a little your belts won't grip well and you will start burning up belts. I'm putting 4 groove pulleys and belts on mine this time.