Anyone repair agricultural equipment?
Discussion
II've got a three bladed finish mower that mounts on the back of a tractor, PTO powered. The gearbox is pissing out oill and I'm trying to find the leak from the gearbox and stop it. I've no idea of the make or age so wondered if anyone on here could help. Here's a pic:
I thought it was leaking from the splined input shaft but I've left it on the bench for a while and it's not dripping. I know it also throws out oil through the breather hole in the filler cap.
Any ideas on on the procedure for replacing the shaft seal round the input shaft, or shall I just start undoing bolts and see where I end up?
I thought it was leaking from the splined input shaft but I've left it on the bench for a while and it's not dripping. I know it also throws out oil through the breather hole in the filler cap.
Any ideas on on the procedure for replacing the shaft seal round the input shaft, or shall I just start undoing bolts and see where I end up?
The four inner most bolts that have the remnants of the black plastic thing - this was the round plastic PTO Shaft guard- cosmetic H&S usually broken within the first two years as the plastic gets hard and brittle from the weather - these 4 bolts won't be the source of your leak as they should be blind - ie they only are tapped some of the way into the housing and are a dead end.
What grade of oil do you have in the gearbox and what qty?
If oil is coming out of your breather I suspect the gearbox is overfilled
The bung at the side is a level bung - with the gearbox level, open this and if any oil runs out the gearbox is overfilled.
The correct grade of oil for most of these gearboxes is 80/90 gear oil - nasty green thick smelly stuff probably best to drain the box and fill to the level with new oil when you have the gearbox on the bench.
other leak sources could be your input seal but this looks ok as far as I can see. or you have a cracked gearbox casing which is weeping when the gearbox gets hot.
hope this helps.
What grade of oil do you have in the gearbox and what qty?
If oil is coming out of your breather I suspect the gearbox is overfilled
The bung at the side is a level bung - with the gearbox level, open this and if any oil runs out the gearbox is overfilled.
The correct grade of oil for most of these gearboxes is 80/90 gear oil - nasty green thick smelly stuff probably best to drain the box and fill to the level with new oil when you have the gearbox on the bench.
other leak sources could be your input seal but this looks ok as far as I can see. or you have a cracked gearbox casing which is weeping when the gearbox gets hot.
hope this helps.
Thanks, I suspected that was the remnants of a guard, but didn't know for sure.
I've been topping up with 80/90 GL5 but don't know what was in there already. It loses that much that there can't be much of the old left anyway. I'll empty and refil with with fresh anyway.
I've tried to be spot on with the level, filling half way up the sight glass. However, the mower get used on steep gradients mostly and I'm wondering if that is why it is throwing oil out of the breather cap....
I was convinced it was leaking around the input shaft too, but now I've got it on the bench I'm starting to doubt myself.
I think I'll reinstall it with fresh oil and run it on the level and play spot the leak.
I've been topping up with 80/90 GL5 but don't know what was in there already. It loses that much that there can't be much of the old left anyway. I'll empty and refil with with fresh anyway.
I've tried to be spot on with the level, filling half way up the sight glass. However, the mower get used on steep gradients mostly and I'm wondering if that is why it is throwing oil out of the breather cap....
I was convinced it was leaking around the input shaft too, but now I've got it on the bench I'm starting to doubt myself.
I think I'll reinstall it with fresh oil and run it on the level and play spot the leak.
Again check the oil level can't be too full as said. If ok correct oil type and amount etc. the breather could be a spring loaded type remove and have a look .could be jammed open. If all good and still throws out some g boxs have a plate over gears to stop oil flow and can fall off. So run up when cleaned off with correct oil and good luck. Richard
Breather is just hole in the side of the yellow plastic filler cap,no spring or valve. You can just make it out in the first photo. I could perhaps secure a fine mesh or something on the underside of the filler cap to catch oil but still let air pass.
Having checked on it earlier, it is weeping from the input shaft seal too, so it now looks like this and a new seal is on order...
On looking at the shaft, there seems to be fine groove worn where the seal runs so will have to see if a new one seals any better.
Having checked on it earlier, it is weeping from the input shaft seal too, so it now looks like this and a new seal is on order...
On looking at the shaft, there seems to be fine groove worn where the seal runs so will have to see if a new one seals any better.
If there could be an issue with the wear & corrosion on the shaft you might consider a Speedi-sleeve.
Link here: http://www.skf.com/uk/products/seals/industrial-se...
Link here: http://www.skf.com/uk/products/seals/industrial-se...
paintman said:
If there could be an issue with the wear & corrosion on the shaft you might consider a Speedi-sleeve.
Link here: http://www.skf.com/uk/products/seals/industrial-se...
I like those! If a new seal doesn't do it, I'll give one a try. The Speedi Sleeve isn't cheap so I'll try as is first.Link here: http://www.skf.com/uk/products/seals/industrial-se...
I take it's a double lip seal. So clean it up well with emery etc round and round. Most of the grove is under the dirt seal inner seal facing may we'll be better . Check seal on shaft before fitting in housing to see if it fits well as you can get sloppy after market ones. If it is not tight enough remove spring round inner lip take apart (un screw it) cut a bit out screw back together. Also if new seal is not rubber coated on outside as many are not refit with gasket compound. So no splash guard ? Hopefully it was over full. Richard
griff 200 said:
I take it's a double lip seal. So clean it up well with emery etc round and round. Most of the grove is under the dirt seal inner seal facing may we'll be better . Check seal on shaft before fitting in housing to see if it fits well as you can get sloppy after market ones. If it is not tight enough remove spring round inner lip take apart (un screw it) cut a bit out screw back together. Also if new seal is not rubber coated on outside as many are not refit with gasket compound. So no splash guard ? Hopefully it was over full. Richard
No splash guard, you can just look straight down onto the bevel gears. It may be that as I use the mower on steep hills, that plays havoc with the oil level and hence the stuff coming out.If the grove is too bad and it doesn't look like it you can fit a spacer washer under seal , press seal in to spacer this will leave seal in a different place on the shaft by a couple of mm so running on good unworn shaft !! Spacer helps to fit seal square in bore. If that makes sense. .
griff 200 said:
If the grove is too bad and it doesn't look like it you can fit a spacer washer under seal , press seal in to spacer this will leave seal in a different place on the shaft by a couple of mm so running on good unworn shaft !! Spacer helps to fit seal square in bore. If that makes sense. .
I'd have to carefully weigh up the clearance behind. I think it's pretty close to the bearing, the seal might foul if it's not seated all the way in.
There is an easy cure for a worn shaft that I have used in many [a few] situations and is entirely sucsessful google speeda sleeve and find out about this very simple way of reclaiming worn shafts . I mainly used them on Deutz air cooled diesel crankshafts front and rear ,they atre not silly expensive and do work HTH
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