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PearceLawn
06-13-2007, 09:01 PM
I have a Dixon Ram Mag 50" mower with a 20 hp Honda engine. The left hydro pump has developed a chattering noise and loss of power while going up hill or if you push the sticks forward too fast.

If it had gears I would say it feels as if the teeth were slipping by one another.That is the feeling I get from the sticks.

Once I pull back and accelerate slower it stops. It doesn't bog the engine down so it isn't drawing excess power.

Fluid level is good and fluid is clean. The right side seems fine.

Any ideas guys?


Note to Dixon haters....If you are going to bash my equipment choice at least say something constructive to solve the problem too!!! :rolleyes:

bbpropmaint
06-13-2007, 10:29 PM
i have the same prob on my exmark..happened today... if anyone can offer any suggestions it would be appreciated

lzrj
06-13-2007, 11:30 PM
May have some insight because I just dealt with something similar. The left Hydro on my Everride Warrior had no power up hills and what sounded like a "grind" occurred occasionally until I backed off the stick. Thought it was the pump that was going bad but after the work was completed, it was the just the pump belt that was loose and slipping. Not sure how that whole belt and pump system works but thats what the mechanic told me. He said Everride had a recall and my belt was not changed to the new one which caused it. Check the belt and pulley.

Jason Rose
06-14-2007, 12:35 AM
The Ram Mag has the seperate pumps and wheel motors, correct?

I ask because my Kodiak is in the shop currently for the exact same problem. I noticed it doing the same thing a week or so ago and it was getting worse each day. After several hours of use I was loosing power to one side totally. For Parker pumps and wheel motors I'm NOT IMPRESSED!!! This is the second failure I've had. The first time was a blown seal in the other pump, that required replacement, and now this! Granted it's under warranty, but I'm without my good machine for who knows how long.

What's funny is that everyone BASHES Dixon, but it's not their parts failing! Parker is the top brand of hydraulics used on most machines. My Kohler engine isn't much better. It's supposed to get checked out too while it's in there. It's using roughly 8 to 10 ounces of oil every 2 to 3 days. That's definately NOT right!

My Dixon is roughly 15 months old (several of those was winter, lol) and I have 900 hours on the machine already.

ow man
06-14-2007, 01:33 AM
Hope this helps. I have some experience with Hydrogear. First check to make sure your belts are tight. BUT this sounds like the classic worn pump swash plate that is inside your hydro pump. There will be a light "smearing" on this plate. This is what your pump pistons ride on that drives the fluid. When it gets worn "light grooves" in it, it will lose pressure. This especially happens up hills or when the fluid gets warm after a few minutes. Some causes of this are, dirt in the hydro oil , (it may look clean, but may not be clean) or air cavitation. Hydro systems need bleeding if they have air in the unit. It will usually chatter or whine really loud. Also hard curb hopping causes damage. This hard quick back pressure on the pump while hitting a curb will push the pump pistons off the swash plate inside the pump for a split second and then slam them back down. This causes smearing and in time, looses power. Picture the smearing on a rod and crankshaft journal on an engine ran low on oil. That is similar to what the hydro plate looks like in the pump. It can be rebuilt, but most of the time it's easier to just replace the pump. Also make sure that if you get metal or junk in your oil, that you do not contaminate your wheel motor. This will wipe out your wheel motor too. Ask your dealer to explain further what I've said. Sorry it took so long to explain, but maybe I've helped out.

Jason Rose
06-14-2007, 01:42 AM
Thanks for the info. Just wondering, does it really matter what type/weight of oil a person uses in a hydro system like this? I read in the manual that 15w40 synthetic is the most recommended oil, or 20w50 Dino. And to not use anything else. My dealers mechanic says it dosn't matter and as a matter of fact he put a quart of 10w30 in the system when they replaced the one pump a couple months back. Oddly enough now I have a pump failure... I wanted to change the fluid as soon as I had got it back, but it's under warranty and I thought I'd let them see their mistakes if something did happen.

PearceLawn
06-14-2007, 04:02 PM
Jason Rose,

I had to have the right one replaced after 50 hours or so because of a leak in the seal. It took almost 3 weeks to get it back.

I do have the separate pumps and wheel motors,you are correct.I have the 20 hp Honda. I have had 100% good luck with every Honda I have ever had so that is what I ordered for this mower. So far it runs like a champ.


lzrj,

I have an extra belt in my possession I had purchased as a precaution. I will put it on this weekend and report back if it did/did not solve it. Maybe the tensioner spring is not as tight either so I can try that too.


ow man,

I am hoping you are not correct!! That would mean some downtime for the machine so it could be repaired. I do not do any curb hopping at all. I mow residentials and 3 convenience stores. I do appreciate your info very much and the next time I am at the dealer I will mention it to him. Especially if I cannot solve this beforehand. It seems to happen all the time not just after it warms up.

ow man
06-14-2007, 07:31 PM
Pearce Lawn, glad I could help. I didn't mean to scare you to death, or say that you curb hop, it's just one thing that causes this condition. Most failures are caused by dirt or air cavitation. Does your mower have HydroGear brand pumps? I didn't mention that I also work for the midwest distributor for HydroGear out of St. Louis Mo. Do check with your dealer and share with him what you have learned. (especially if it's a Hydrogear brand) I don't know how the other brands are built. Hope you get it figured out. Good luck.

Restrorob
06-14-2007, 08:59 PM
My dealers mechanic says it dosn't matter and as a matter of fact he put a quart of 10w30 in the system

Jason, If that guy was stupid enough to say and do that I would have second thoughts about letting him work on anything of mine.

If it didn't matter the OEM's wouldn't make certain oil recommendations, And it's not good mixing oil weights anyway due to changing the original recommended oils viscosity.

PearceLawn
06-20-2007, 07:40 PM
Jason,

Did you get your machine back? If you did what was the problem?

Jason Rose
06-20-2007, 07:49 PM
Jason,

Did you get your machine back? If you did what was the problem?

Yes, got it back, they replaced the pump in question. Of course they didn't do it quietly! The machine has a 3 year warranty (2 yr. parts and labor) and yet they were griping that it had 850 hours and really shouldn't be covered with that many hours. I'm thinking "excuse me?" warranty is warranty, they didn't put a cap on the number of hours, that's their problem.

Now I'm having some engine problems, likely carburetor, but not 100% sure, it may be the centrifugal governor. Going to TRY to get the carb off tonight and clean it out, see if that helps. It's an absolute NIGHTMARE to get too because of all the crap bolted on in front of it that's impedes its removal. I'd take it to the dealer, but there's that WARRANTY issue again. They told me that Kohler would not honor a warranty claim with that many hours on it, even though it's still well within the warranty timeframe.

PearceLawn
06-20-2007, 08:23 PM
You are absolutely correct on the warrenty thing. Number of hours has nothing to do with it. After all they sell them as commercial machines and commercial machines get used. My dealer has been good about that stuff so far.

The pump isn't getting any worse so I am going to try to milk it out some more before taking it in. It is just a minor annoyance right now. I have to call for jury duty in mid July so I thought as long as I am going to be out I might as well have it looked at then. It will give the dealer time to get all the parts he needs to git-r-done in a reasonably short time.

Good luck with the engine issue. Man I love the Honda's!!

Thanks for the info too.

Jason Rose
06-21-2007, 01:21 AM
Engine update. Took the carb off tonight, (what a mess to get it off and back on again) but that only made it run a LITTLE better. Now we can hear the clattering on acceleration of the govenor ball bearings. That plus the oil consumption and I'm facing the facts that it's going to be down for some time and have a LARGE repair bill in front of me. I'm not sure weather they will recommend re-build or just go in with a new shortblock.

I'm going to push the warranty issue for sure. Total BS that kohler dosn't stand behind warrantys.

PearceLawn
07-13-2007, 10:36 PM
Just a little update.

I have to call for jury duty next week and was going to take the mower in then. As it turns out I blew the drive belt while mowing yesterday afternoon. After 1.5 frustrating hours of trying to get the belt on with only one hand (cause that is all that will fit) I finally got the new belt on.

Well I be dipped.....the chattering is gone. No need to get it to the shop at all.

Thanks to all for all the great info.

Karl

ed2hess
07-13-2007, 10:56 PM
Engine update. Took the carb off tonight, (what a mess to get it off and back on again) but that only made it run a LITTLE better. Now we can hear the clattering on acceleration of the govenor ball bearings. That plus the oil consumption and I'm facing the facts that it's going to be down for some time and have a LARGE repair bill in front of me. I'm not sure weather they will recommend re-build or just go in with a new shortblock.

I'm going to push the warranty issue for sure. Total BS that kohler dosn't stand behind warrantys.

Jason...I have had pretty good luck with Kohler warranty ...during the first two years The one exception are the stupid carb.....won't replace a broken one on 15hp....said only 90days.

Restrorob
07-13-2007, 11:13 PM
Total BS that kohler dosn't stand behind warrantys.

Jason, It's not Kohler saying they will not cover your warranty.

It's your sorry azz dealer's BS on that, I'd be willing to bet he does this to get double pay from customers. Charges them then turns around and files a warranty claim with Kohler.

I have NEVER in my 16yrs. had Kohler not pay a claim. I have never had any issues with the hours that were put on a unit with-in the warranty time frame. I have even gotten Kohler to pay for parts (only) needed on a couple units that were out of warranty.

Kohler really does like to take care of their end users, So don't believe everything your dealer tells you.

Jason Rose
07-13-2007, 11:50 PM
Jason...I have had pretty good luck with Kohler warranty ...during the first two years The one exception are the stupid carb.....won't replace a broken one on 15hp....said only 90days.

Jason, It's not Kohler saying they will not cover your warranty.

It's your sorry azz dealer's BS on that, I'd be willing to bet he does this to get double pay from customers. Charges them then turns around and files a warranty claim with Kohler.

I have NEVER in my 16yrs. had Kohler not pay a claim. I have never had any issues with the hours that were put on a unit with-in the warranty time frame. I have even gotten Kohler to pay for parts (only) needed on a couple units that were out of warranty.

Kohler really does like to take care of their end users, So don't believe everything your dealer tells you.

Thanks for the info guys! I was wondering where you two guys were when this thread started...

I wound up taking the machine to a different dealer, the problem turned out to be a LOT of dirt in the carb. Don't know how, but there was a bunch of dirt flowing right past the filter. I had cleaned the carb. once, then this guy ended up pulling it off 4 times to get it all cleaned out. (also flushed the fuel lines and put on another new filter) Now it runs fine. The other dealer still insists that it needs a valve job to make it run right. Of course I ended up paying for the repairs, because it was dirt causing the problem, but my original dealer made too much noise already about it. I finally gave the owner of the place an ear full the other day after having to take it in AGAIN because of a blown hydro line. I told him what a crap mechanic he had and just what kind of BS he was telling me. Now, the reason I took it back there, the blown hydro line, was the mechanics fault! Had the pump replaced and this one armed goof torqued the fitting down and put the line in a kink right at the fitting. It was not only fixed for free, I insisted on it being delieverd to my house, since they negleced to call me when it was done.

I ordered a new Grasshopper on Monday.

cranesrule
07-14-2007, 01:08 AM
Pearcelawn,
I believe your unit has Hydrogear IZT transaxles not separate pumps and motors, correct?

PearceLawn
07-14-2007, 10:13 AM
Pearcelawn,
I believe your unit has Hydrogear IZT transaxles not separate pumps and motors, correct?

Separate pumps and motors and boy are they packed in there tight. No way to get two hands in there unless you jack the unit up.


Jason,

Glad you got it straightened out.

razor1
07-14-2007, 10:30 AM
Pearce Lawn, glad I could help. I didn't mean to scare you to death, or say that you curb hop, it's just one thing that causes this condition. Most failures are caused by dirt or air cavitation. Does your mower have HydroGear brand pumps? I didn't mention that I also work for the midwest distributor for HydroGear out of St. Louis Mo. Do check with your dealer and share with him what you have learned. (especially if it's a Hydrogear brand) I don't know how the other brands are built. Hope you get it figured out. Good luck.

ow man, since you work for hydrogear. What's the mark-up on a hydro pump anyway? They sell for approx. $3-400. retail. Can you buy direct from hydrogear?