370 SD Transmission Noise

[ajaymuch]

I have a 1996 370 Sundancer with gas 310's. It has gas engines. When I engage the starboard transmission it makes a whine like noise. This is the first year I have experienced this. The boat has 300 hours. The transmissions are Hurths. Anything to concern myself about or is this a normal characteristic of this model?

 

[thomas]

Might be wise to check your tranny fluid, while your down there check your oil

 

[Big Al]

Is it loud or light ? I also have a similar sound when I engaged the trannies, but a very light sound.

 

[goblue]

How often do you change your transmission fluid and filters? What does the fluid look and smell like?

 

[ajaymuch]

370 TransmissionNoise

Thanks for the response. The fluid is dark red and does not smell burned. I have never changed the fluid or filters. The souund is pretty light but certainly noticeable compared to the other side. Fluid level is right where it should be. Any moe suggestions?

 

[J Levine]

To provide the counter rotation of your props on of your transmission is technically in "reverse". I have been running the same set up as yours for a number of years as I have always noticed a very slight difference in sound between the transmissions especially at idle speed when backing down at the dock. Could it be that you just have never noticed this? Their is actually a very small difference in the effective gear ratio between the two transmission when the are both shifted into the same direction, Sea Ray usually adjusts the prop pitch between the two wheels to account for this. As far as changing the fluid and filter I think the spec is like every 100 hours or so. I do it every other season. It is not too difficult especially if you use an electric oil removal pump and install drain hoses on the transmission which I have done. The drain plugs are 1/2" NPT. The filters are pricey at about 70 bucks each but the fluid is just Dextron III.

One last thought on the subject, I check the fluid level each weekend before I use the boat for the first time. My big concern is the trany oil coolers. If they fail, the transmission will pump all of its fluid into the raw water stream and then sea water will come back into the transmisson. Over the years a couple of guys on these boards have suffered this failure, which if not caught imediately will trash the transmission. As I result I am looking for any evidence of water in the transmissions. Mine have almost 800 hours on them and are working great, and I want to keep it that way!

Jon

 

[37 Dancer]

roger to what Jon said........

I too have the same exact set up on my 370DA........and have a slight whining noise in my PORT tranny.

I had a tranny cooler let go last season and had raw water in the tranny fluid for about a day. I flushed it with 25 quarts of fresh fluid.....then changed the filter. Had my mechanic run a test ( pressure ) and all was fine. He said they are almost bullet proof units. :grin:

I learned to check my fluids EVERY time before I leave the dock !

 

[Hampton]

What do you guys think of this? I un-screw the Tranny Cap a little until air rushes out, and then seal them back up.

Positive air pressure tells me the system is still sealed tight. If the coolers were leaking, the system would quickly lose its pressure after shutting down.

I also check the fluid level and color every couple of weeks, but not every week.

 

[37 Dancer]

once you break the vacuum.......it only take another 5 seconds to see that the fluid is full..... pink and water free.

Its worth the time for me.................. :thumbsup:

 

[ajaymuch]

Thanks guys for all the feedback. I will change the fluid and filters. Good advice about checking the tranny fluid often. I have added it to my list of b4 you leave the dock checks

Rick