OutdoorKing Repair Forum Forums Repairs and Maintenance Questions On Ride On Mowers Questions On Ride On Mowers Frames Bolens st160

Hi All, couple of questions about my bolens.

1. where can i buy decals for my st160?
2. My mower has a peerless 1300 series transaxle and an eaton7 hydrostatic pump. I have flushed both and refilled hoping to fix a problem. It is still occurring, when i run the mower for a while, if i turn to go up a reasonable slope, the mower pauses then sometimes grips\pauses\grips etc, like something is slipping or locking\unlocking. It doesn't do it all the time but susally after it heats up a bit. Sometimes i can put my foot down to go foreward on a slope and it won't go foreward, i let my foot off an back on and nothing, or it will slllooowwwllyyy creep along then get going.. Seems like this might be a hydro problem but i'm not sure, no noises (like a slipping belt etc) just intermittent drive. Also does it in reverse sometimes.

Any help appreciated.

Thanks

Gary

Sounds like low fluid level in the transmission, or a problem bleeding the air out of part of it. You shouldn't operate it in that condition - you'll be causing cavitation damage if my diagnosis is correct.

Thanks Grumpy, do you mean the transmission or the pump? it started doing it after i had it for 12 months or so, no fluid leaks anywhere. i filled the pump up to the top plug and the transmission up to the front bung. Not sure what else to do, however i have not rechecked the pump level but it's doing exactly as it was before i touched it anyway.

Gary

My Bolens ST140 does the same thing.
I have tried adding oil to the hydro and gearbox but no change. I did note this problem was happening on full steering lock going up a hill. In a straight line no issues. At one stage I also noticed some wheel spin especially if the grass was quite damp which was adding to the problem
What oil are you using in the hydro or the gearbox. ?

Hi Cliff, yes, EXACTLY the same circumstances here too. i put in 80w 90 in gearbox and 4 stroke sae30 motor oil in hydro.

This is the correct oil for the 1300 series transmission. The workshop manual covering all the peerless transmissions is in the parts list and manuals area HERE

Oil Bath
S.A.E. E.P. 90 oil

Thanks Bruce, what would you think the problem might be that we are discussing? I would like to hear your input

Incorrect Oil and possibly quantity.

If I read Bruce's post correctly, the proper oil for that hydrostatic unit is EP90, and you are using straight SAE30. You also said that the problem does not arise until after warm-up of the unit. I may have misunderstood both of you, but if my summary above is correct, it sounds like you may have been boiling the light oil you have incorrectly put in the hydrostatic unit and it has cavitated extensively. There may be pretty severe damage if that is what has happened. Of course severe under-filling or an air-lock is another possibility.

Usually cavitation is accompanied by some distinctive noises, in my experience typically sounding like a loose ball from a ball-bearing getting smashed to pieces by going through some gears. That is followed by loss of drive, sometimes due to almost complete destruction of the hydraulic pump. Well, that is how it shaped up when it happened to my front-loader backhoe anyway. Boy that was expensive.

Ok, well, as i wrote before, i used 80w90 in the transaxle and sae30 in the hydrostatic pump, TWO SEPERATE UNITS although they are bolted together. the pump has it's own sae30 and the transaxle has EP90 oil. There are NO NOISES from either apart from the renowned whining from the transaxle which i have heard many people report they have in theirs. The hydro pump was filled to the bream, then some added to the res when it was replaced. the transaxle was filled to the front filler plug as it states to do BUT it was 80w90, not EP90. i will drain it and refill with EP90 BUT as i stated before, it was doing the same thing before i touched any oil anywhere, perhaps the old oil was the wrong sort too. Anyway, i will find out soon enough after i refill it.......Will post again with a result but i think it won't change.

Here is some more information from the workshop manual which is located in the parts list and manuals area that might help:

Add 1301ml of the oil.

Well Bruce, i've had a bit more of a look at things and my peerless is a 1327 model which in the manual (lube chart page 7) has NO lube quantity for my model, there is another difference, the 1300 series has 2 bungs, one on the bottom as mine has and one at the top/back which mine doesn't. Mine has one at the front instead around half way up the casing. After filling to this bung i had used under 1 litre of oil. i didnt measure how much but there was i reckon around 1-200 ml left. SO, i think i will just fill it again to this level with the EP90. What do you think?

Gary

Well, now i really AM confused, the Bolens ST160 manual lube chart (p1-14) says to use SAE EP90 1.3 litres and to check the resevoire every 25 hrs ??!?!??! WTF What reservoire. only one is on the hydro pump on mine. and to put 1.3 litres in there i will have to lift the mower on its back legs or take the hydro pump off, doesn't sound right to me. hmmmmmm, thought this would be easy.

Think about this scenario (I'm not saying it's true, I wouldn't know).
1. Maybe it wants EP90 in the hydro pump, but you've been using SAE30.
2. It's never made any funny noises, it just won't drive when the hydro oil warms up.
3. Just maybe, the reason it doesn't drive is that the hot SAE30 is so thin, the hydro pump can't pump it up to pressure - it leaks back through the pump and output pressure is very low.
4. If that happened to all be true, it may be that just by putting the right oil in it, you will find you have full drive capability, and not much damage has been done to anything.

You need to be very sure what oil that hydro unit is supposed to use. I wouldn't want to put EP90 in one made for SAE30, or you might wreck it. But if you put SAE30 in one made for EP90, I wouldn't expect much output pressure once the oil heated up, if it had any wear on the pump.

Sounds reasonable to me Grumpy, but, the HYDRO manual says you can use-
1. premium hydraulic oil
2. engine crankcase oil - SAE 10w, SAE 20w-20, SAE 30
3. Automatic Transmission Oil
4. Hydraulic Transmission Oil
5. Synthectic fire resistant fluid (with a heap of different brands.

Then it states:

The preferred fluids for all light duty trans, pumps, transaxles and motor axels are those having a viscosity equiv to SAE 20W-20, SAE 30 or SAE 40.

From that, i think that SAE30 shoould be fine. Nothing mentioned about SAE90 in HYDRO PUMP, SAE90 is in the TRANSMISSION. Thanks for your input again though.

That sounds pretty convincing, and I've never personally seen a hydraulic system run on EP90 oil. The EP part would be pretty weird for hydraulics - it is a sulphur compound used for anti-seize properties, but it achieves the anti-seize by eroding the steel slightly. Just the thing for hypoid automotive axles, or other extreme pressure sliding conditions.

Ok, i've put the EP90 in the diff, approx 7-800 ml, the only way to put more in is if i remove the whole thing and remove the hydro pump and add it through the hole where the hydro is removed from. Can't see why that would be needed if there is a front bung half way up the casing.

Anyway, will give it a good run over next couple days.

Ok, i have given this thing a flogging and it seems to be going ok. Cutting 5ft bamboo type stuff and a LOT of it. lots of backwards/forewards motions, diff seems quieter too. Thanks to all for the input. Case Closed. (for now)

smythie good to see that all is well with the trans but it would have been good to drain the pump as well.

You still might have some of the old oil in the trans but see how you go.

Hi smythie,
Congrats on getting it sorted, hoping the prob is finally resolved. Happy mowing,