OutdoorKing Repair Forum Forums Collectors Corner Ride On Hydrostatic poor performance

WOW, been a LOOOONG time. nice to be back. I picked up another Bolens today, ST180. As the subject states, it drives, but, going uphill it will slow down with full revs (motor is doing its job fine) and pedal flat out forward. Even on a flat surface going from a little under half throttle to full throttle makes no difference to forward speed. I did come across something in the manual; about the brakes need to be set spot on so i might disconnect them and see what happens. seems to go ok in reverse though. The shop i got it from traded it in and they said that is the reason the guy got rid of it, one of the shop partners told me it was like that when they got it but he did something to it and seemed to fix it, he DID top up the hydro pump with oil he said, not sure about the axle\gearbox setup. He said if HE got it working it would not have been much lol as he isn't a mechanic, so, just wondering if anyone has any more ideas. i have iot on loan for a few days to see if i want it or not so i'm on very limited time. i still have my old ST160 but the motor is not worth repairing and i need a mower FAST, grass is growing and my other thoughts are i have the 160 for spares. I think it has the eaton7\peerson 1327c setup, my other hydro setup is working fine so if need be i could swap them if it will fit, the 180 looks a little bigger frame wise, waiting for tomorrow, 22 deg c, great day to pull things to bits...hope someone might be able to suggest things as i really want AND NEED this mower....Cheers.

I suggest that unless someone here has worked on an ST180, you need to go through the process of familiarising yourself with it before you resort to the spanners.

Here is a place where you can download the service manual:
http://sonnys_bolens.tripod.com/manuals/suburban.htm

Under ST Suburban series press DOWNLOAD to get the 113 page service manual for the full ST series.

If you do some searching you will find that the ST180 is the advertising name for several different 3018 models. The 3018G had a Peerless 801-018C transmission, the 3018H-01 had an Eaton 7 hydrostatic drive/Peerless 1327C final drive combination, and the 3018H-02 had the Eaton 750. So, what transmission do you currently have?

Generically, to check a fault such as you have you begin by checking that the V belt driving the transmission is not slipping, the transmission shift linkage is engaging properly, the speed pedal is moving the external transmission control for its full stroke, and the transit lever has not been engaged. Then you inspect the transmission fluid level and condition. Often there is an externally-accessible filter, which may be blocked.

At that point, if the transmission is full of clean fluid but it does not drive forward, it looks as if there is an internal fault. Since it drives backwards, it will not be in the drive gears, but will be a blockage in the internal fluid filter (if it does not have an external one, it will have an internal one) or a fault in the internal hydro pump or hydro motor. You have to remove and dismantle the transmission to deal with any of those problems.

If the fluid is heavily discoloured it has been overheated. You may be lucky enough to get it working again with a complete fluid change and cleaned or replaced filter, but unless the abuse that cooked the fluid was brief and recent, pumping the damaged fluid through the transmission for a long period will have worn out the hydraulic pump, hydraulic motor, or both. Sometimes there are kits available to rebuild those parts.

And the very short summary is that there is a model of ST180 that used the same hydrostatic unit and final drive unit (Eaton 7/Peerless 1327C) that you have in your other ride-on, so it may or may not be practical to switch that unit into your ST180 if that is what you choose to do. If you tell us what transmission your ST180 currently has, we can talk about that.

WELL, it WAS a stuffed drive belt but i'm glad i delved. Very little oil in the transaxle and overfilled hydro pump. NEW fresh oil applied and right amount. Couple more questions. Can worn pulleys prematurely wear belts? not as in bearings worn but the surface of a pulley? Just wondering how long this one i put on should last, it is used, off my ST160, but i don't fancy replacing it again any time soon as it takes a bit to replace. The fuel cap has a plastic clear dome so you can see the gauge ,this is broken so dust and moisture can get in there, i was going to plug the tiny hole in the centre but the tank needs to breathe, any suggestions?

Thanks, glad to be cutting grass again!!

Thank you for that report, smythie, it is much easier to do these things from a distance when you explain the situation that clearly.

First, when V pulleys wear, the belt rides lower in the pulley. The problem arises when the belt gets to the bottom of the pulley, because then it can no longer jam in the V, so it slips without transmitting much power. By inspecting the bottom of the pulley and the bottom of the belt, you can usually tell if the pulley is nearing its use-by date. Meanwhile, if the contact surfaces in the V of the V pulley are rough, that will cause some wear to the belt, until the belt wears them smooth. I do not see how they could get rough, except by rusting while the machine was out of service, and was perhaps left out of doors. Such rust would probably be removed from the pulley by the belt fairly quickly when the machine was put back to work. If the rust disappears in an hour or so of running, it probably will have had relatively little effect on the belt life.

Second, the fuel tank cap vent only needs to be about 2 mm diameter. Smaller than that, there is more likely to be a dirt-plugging problem. If the cap is cracked, you may be able to fix it with epoxy and re-drill the 2 mm vent hole afterwards.

Thanks for the info Grumpy. One of the pulleys is shot, looks like it has a worn inner edge and a thin lip (if that makes sense) sort of a groove where the back thick part of the belt has been running just inside the pulley, the old belt was countersunk into the pulleys it was worn that much and must have worn a groove into the pulley. it's a hard deck to get the right belt for apparently, i tried 2 locals and they both said it's an odd size belt. 168.5 inches. Does not state if that's ID or OD. Anyway i got a substitute today and it goes on but the tensioner is almost flat out so i don't think i'll get much use from this belt unless i can take up some slack (replace one of the pulleys with a bigger one) but the mower guy said they sometimes shrink after use!?!?!?! It's a Bolens 30048s. Anyhow, runs MUCH smoother now with new spindle bearings and all regreased, some pulleys swapperd over, can hardly hear it now . Just gotta replace that one worn one then on to other parts of the mower. Thanks for the input mate, all appreciated.

Oh yeah, my model says 3018HA, not -1 or -2, A for Australia?

Which transmission does your mower have?