MikeB 2 #1 Posted February 26, 2015 I recently purchased a 1998 520xi. It only has approximately 400 hours on it and is in excellent shape. I am trying to figure out how to fix the screeching noise when lifting and lowering the 2 stage 44" snowblower. I removed the hydro lift valve thinking it may be the culplrit but I'm not 100% sure. Can anybody assure me this is where the problem is before I go any further with this? It lifts and lowers fine, and the tractor works fine...it just has this annoying noise and I want to fix it. Share this post Link to post Share on other sites
Pollack Pete 2,273 #2 Posted February 27, 2015 I have two 416-H's.One squeals like crazy.One is quiet with no squea.Someone said they squeal just to remind you that they're still working.The noise doesn't bother me enough to look into it.Raises and lowers just fine. Share this post Link to post Share on other sites
MikeB 2 #3 Posted February 27, 2015 Ok thanks. What I am thinking is that the valve seals are worn and the oil is leaking by causing the noise, but I'm not that confident about it. Share this post Link to post Share on other sites
Rick_in_CT 156 #4 Posted February 27, 2015 Mike, I have attached a page from the 5xi transmission service manual. Following the first paragraph there is a Note concerning noise from the lift valve on non-power steering units. I have 522xi which has power steering, and the lift is not very noisy. It looks like you are in a cold climate, which may also cause the hydro to be noisy. I always run Mobil 1 10W-30 in the hydro. Do you know what is in your hydro and when was the last time the hydro filter was changed. Have you checked the oil level in the hydro? At 400 hours, you shouldn't really be having valve problems, or hydro for that matter. Also note that the last paragraph on the page makes reference to running at full throttle. Are you at WOT when you get the noise. I'm sure some of the other 520 and 518xi owners will chime in and make reference to how noisy their lift valves are. Rick Trans.pdf 4 Share this post Link to post Share on other sites
danjmah 71 #5 Posted February 27, 2015 I have had my 1998 520xi for about a year now with currently 373 hrs. and get the same screeching noise you describe. Seems to work great but often wondered is that noise normal? Share this post Link to post Share on other sites
MikeB 2 #6 Posted February 27, 2015 To All, Well, it appears my question has been answered after reading the attached manual Rick sent to me. "Note, Lift valve noise is normal on manual steering units" Full throttle makes the screeching noise louder then 3/4 throttle. I believe I can reinstall the valve and just live with the noise I guess. At least I can relax and know that I'm not neglecting a problem. Thanks everybody, Mike Share this post Link to post Share on other sites
MikeB 2 #7 Posted February 27, 2015 I should add that I went through the 520xi from front to back and replaced fluids, filters, grease, etc to make sure it is in the best condition possible. It's a good machine, and it works great for blowing my snow for sure. Share this post Link to post Share on other sites
Rick_in_CT 156 #8 Posted February 27, 2015 Mike, Good to hear that you did all the maintenance after getting the machine. That 44" blower certainly can move snow. Rick Share this post Link to post Share on other sites
doc724 924 #9 Posted February 27, 2015 My 2002 520xi (with just under 600 hours) also has this noise, but I am not sure it is a screach. It happens when the lift is at full travel in either direction. Maybe a bypass valve? Anyway I am not concerned about it-especially after reading Rick's note. 1 Share this post Link to post Share on other sites
shallowwatersailor 3,213 #10 Posted February 27, 2015 The noise is very disconcerting the first time you hear it but normal. I was very concerned about the noise when I bought my first, the 518xi in 2010. Even my 523Dxi with PS has a slight noise at times. Reading the manual five years ago that Rick referenced put me at ease. Follow the manual about warmup before using. You may even want to buy a magnetic heater for the transaxle if it is in unheated storage before using. Try not to run it to the "stop" that unloads the excess pressure. You'll soon get the feel for it. If you watch my videos, when I reverse I only raise the snowthrower enough most of the time to not drag on the ground to limit going over full travel. 2 Share this post Link to post Share on other sites
cheesegrader 433 #11 Posted February 27, 2015 I always thought the noise was the bypass valve. My hydro's all make noise to some degree. It is worse in cold weather, and improves as the units warm up. A heater for the hydro is a good idea, even a lightbulb for half an hour might help. I've also gone to synthetic fluid. Regular oil just gets too thick in the cold here. Amsoil 10-30 in the hydro, flows like water even at -30, but it is expensive. Both tricks seem to cut down (but not totally eliminate) the noise. 2 Share this post Link to post Share on other sites
Philnc 4 #12 Posted February 28, 2015 For what it's worth there's a deal on a Toro 5xi Series Hydraulic Service Manual on flea bay now. Share this post Link to post Share on other sites
MikeB 2 #13 Posted February 28, 2015 Update concerning the screeching noise from the Hydro Lift Valve on my 520xi Wheelhorse. The problem was resolved today. Being I had gone through the trouble of removing the lift valve, I wanted to try to get some answers before I reinstalled it. I took the valve to a guy that specializes in hydraulics and explained the problem to him. He is somewhat familiar with Wheelhorse as it turns out. He examined the valve and determined it was in good shape and clean. He suggested that the valve may be a little undersized for the power of the Hydro. He also mentioned the bypass spring may be getting a little weak due to age and we decided to tighten it just a tad. (It's located under the acorn nut alongside the piston valve that the handle connects to...use an allen wrench to make adjustments) He only tightened it about 1/4 turn. I took the valve home and reinstalled it on my 520xi and tried it out. It was better, but still screeched some, so I removed the acorn nut and tightened it another 1/4 turn. That did the trick! No more screeching and the snowblower raises and lowers like a champ, with the bypass letting out a screech only when I reached the up/down limits just as it is supposed to do. I experimented with it blowing some snow and I also found out that instead of running the engine at 100% full throttle, I can run it just a tad under full throttle, like 95% or more and everything works just a little more perfect! The tractor runs great, the snowblower works great, and I don't hear any annoying screeching whatsoever unless I hit the up/down limits. I am very happy with the results!! Thanks to all of you for giving me your input. It is much appreciated! By the way, I keep my tractor in a heated shop, so the cold weather is not a problem for me. Mike 1 Share this post Link to post Share on other sites
bmsgaffer 2,043 #14 Posted February 28, 2015 (edited) I am not entirely familiar with the valve internals, but I do know that that is the pressure release valve up under the cap and it is adjustable. I would have you or your hydraulic guy put a pressure gauge on the lift system to ensure the bypass is still operating at about 700 psi. The eaton is rated for 800 max i think, any more and you can cause permanent pump damage if operated for too long. You are probably right about the weak spring, but I would hate to operate it too long without testing pressure. Just some food for thought Edited February 28, 2015 by bmsgaffer Share this post Link to post Share on other sites
rmaynard 14,909 #15 Posted February 28, 2015 I too experienced screeching noises in the lift valve of my 416-H (1560 hours). After draining all the fluid from the hydro, and refilling with fully synthetic 10w30, the noise lessened by about 75%. Share this post Link to post Share on other sites
MikeB 2 #16 Posted February 28, 2015 I understand the pressure concerns for sure. I do know that everything is working quieter, smoother, and better than it has since I bought it. It is operating like a new machine now. I will make sure I get a pressure check before next season. Thanks 1 Share this post Link to post Share on other sites