Recently purchased a 1982 MCI MC9 conversion. It has what I would describe as a "hydraulic whine" when you turn the steering wheel. What should I look for? Is it a major concern?
Wrong weight oil or out of oil.>>>Dan
yes it is a major concern.
My Sheppard steering with 15W-40 engine oil whines when it is cold. Once warmed up it makes a light whining sound, but nothing much. Some whining is normal for any hydraulic pump. Good Luck, TomC
5 or 10 weight oil,, or ATF will do the job nicely and quiet it down.>>>Dan
MCI's have 2 filters 1 in the reservoir and 1 on the pressure side of the power steering they probably have never been serviced the one in the reservoir is a throw away type the pressure side is cleanable service those and it will make a difference
Thanks for the replies. I will check the level (as soon as I locate the reservoir...lol) and filters.
Also, just to clarify the noise comes from the area of the steering box in the front of the bus not the pump.
I noticed the first time out this spring with the bus I had a noticeable whine I narrowed it down to the steering ( I have sheppard steering ) It was cold around 40 degrees the whining stopped when it warmed up, I checked the fluid level it was a little low, I added a little over a quart of 10w40 motor oil, it quit but still a little noticeable when the wheel is held against the stop.which I think is normal.>>>> John.
Did a little research and need even more advice now. This bus has been repowered with a series 50 detroit. The reservoir has been relocated and the lines extended. That doesn't concern me much but when I messaged the previous owner to ask what oil he used his reply was "any power steering fluid" I have several trips coming up in the next couple months. What should I do now??
when in doubt...use 0w30 synthetic... at least i do.
It seems a little late to "discover" which engine it has,, and other changes,, looks like you have an education in your future.>>>Dan
I just repowered with a 50 series and now I also notice a whine in the power steering ??? It does seem to have more psi than my old pump so I thought maybe my old pump was just wore out put I'm not sure now.
I did not just discover that it has a series 50. I knew that going into it and researched the engine and transmission extensively.
I just discovered the power steering system changes and was looking for advice on what to do about the fluid.
I am sure that I have lots of learning to do...but that is not a bad thing.
jmblake , The previous owner of my bus also says the whining started after the repower. Maybe higher output pump is causing it??
Could be to high of pressure and flow, hydraulics whine when to much oil is being bypassed through the valves that is why they whine against the stops
Quote from: steve.barnett71 on June 02, 2016, 03:15:27 AM
jmblake , The previous owner of my bus also says the whining started after the repower. Maybe higher output pump is causing it??
is there a pressure relief adjustment some where ?
Is there anyway to turn them down? The doner bus had a hydraulic fan also.
Jason
Quote from: jmblake on June 02, 2016, 09:45:37 AM
Is there anyway to turn them down? The doner bus had a hydraulic fan also.
Jason
turning them down may not be the answer, it may need more...there is always a pressure control somewhere... could be shims, could be a screw... could be a spring... but it is not,..... what happens if i do not know...
Oil ; the book on my 60 series says use motor oil. I had used atf and noticed there were allot of foam with it. Changed over to 10w40 that I use in motor and cleared that up. Don't know if it will be the answer for you guys problem. Again don't know science behind this. Couldn't see where you couldn't adjust pressure on 60series. Seem to remember 2200lb somewhere in the book. FWIW cavation? Bob
Are you sure the noise comes from the steering box? Sound transmits through hydraulic pressure very good. If it's actually coming from the pump I would suspect what Bob said, cavitation. Mine started making noise like you described. Took a while to find the problem. Turns out there was a piece of rubber from one of the hoses stuck in the fitting coming out of the filter housing going to the pump suction. Just another possibility.
More research today. Noise is definitely coming from the steering box, not the pump. Pump is quiet when turning the steering. I do not think it is cavitation. Did notice that there is a little bit of foam in the sight glass of the reservoir. I think the next step is flushing and changing the fluid. The only question is what fluid to use. The manual for the steering box lists many different fluids and oils that are acceptable.
Quote from: steve.barnett71 on June 04, 2016, 06:28:47 PM
More research today. Noise is definitely coming from the steering box, not the pump. Pump is quiet when turning the steering. I do not think it is cavitation. Did notice that there is a little bit of foam in the sight glass of the reservoir. I think the next step is flushing and changing the fluid. The only question is what fluid to use. The manual for the steering box lists many different fluids and oils that are acceptable.
how can you think it is not cavitation when foam is a clear sign that it is...?
cavitation the formation of bubbles in a liquid, typically by the movement of a propeller through it.
Acts like low fluid, pump is sucking air - fwiw
I would replace the filter in the reservoir, and clean the one in the pressure line.
JC
Cross over guys--from 2 cycle to 50/60 series. I know pumps are in different locations. ? I have does fluid requirements change between these generations? Mixing atf and oil?
I used hydraulic oil with my old engine so that's what I used with the 50 series ??? If I fill mine to the sight glass it will push fluid out the breather but once it seeks its level there is no oil in the sight glass when its not running but with it running it is right in the middle of the sight glass.
Jason
We just got back from another short trip and pulled into the drive way and seen oil dripping from the engine compartment and discovered what looks like the gasket that holds the lid on the power steering reservoir has blown >:( so now I got a big mess of oil film all over everything. I'm going to order new filter and gasket for the reservoir tomorrow so now witch oil should I use ??? Will one quite the whine any more than the other?
Thanks Jason
Quote from: jmblake on June 12, 2016, 06:16:08 PM
We just got back from another short trip and pulled into the drive way and seen oil dripping from the engine compartment and discovered what looks like the gasket that holds the lid on the power steering reservoir has blown >:( so now I got a big mess of oil film all over everything. I'm going to order new filter and gasket for the reservoir tomorrow so now witch oil should I use ??? Will one quite the whine any more than the other?
Thanks Jason
every power steering system i ever put 0w30 synthetic in benefited never in a coach but lots of Kenworths and other heavy trucks and every japanese car or truck, Fords and Chevrolet's too...
and in the Arctic it was a lot, run year round.
Jason,you need to check your pressure the MCI 8 was a 1000 psi max and the pump on the 50 series is probably around 1450 to 1800 psi same as mine on the 60 series you shouldn't have enough pressure on the reservoir to blow a gasket
On the two strokes, if you ever blow the seal between the pump and engine, you're pouring pump fluid into the engine. So that risk alone has me putting 30 weight oil into my power steering in case this ever happened
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Quote from: luvrbus on June 12, 2016, 08:06:28 PM
Jason,you need to check your pressure the MCI 8 was a 1000 psi max and the pump on the 50 series is probably around 1450 to 1800 psi same as mine on the 60 series you shouldn't have enough pressure on the reservoir to blow a gasket
Is there any way to adjust the pressure coming from the 50 series pump?
I have seen the whine fixed by putting a larger return oil line on the tank. This could be the problem if it blew the gasket.
Jack
The gasket may have been my fault :-[ I loosened the the top to spin it because the breather was hitting the bulkhead and I didn't remove it to check the gasket I just assumed it was ok. I got a new gasket and filter coming.
Now I got a hose up front leaking on the power steering so I'll might as well replace both of them >:(
Jack, Not sure of the size but the line from the tank to the pump is large as I had to reduce it down twice to get to the tank fitting size.
Thanks Jason
Would the Allison ATF synthetic that I used in the transmission work for the power steering?
Changed my fluid over to ATF and drove over 200 miles this weekend. Whining noise is greatly reduced. Will clean pressure filter next
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I flushed the system out and put the Alllison synthetic ATF in this weekend, also changed the filter in the can and cleaned the in line filter. Didn't get to drive it any where but just starting it up it seems quieter then before when revving it up. Keeping my fingers crossed.
Jason