Transmission Fluid change
- Thread starter Alansails
- Start date
To change the fluid you need very few tools. A cresent wrench, an extractor pump and a screw on style funnel. Use Dexron II or Dextron III transmission fluid and you only need .63 pints (0.3L) to fill the transmission (full spec on page 38 of the operations manual for the engine on the Boat page of my blog).
Run the engine for a few minutes to heat up the fluid, extract the fluid from the dip stick hole, fill with new, run a few minutes again and check the level. Takes about 30 minutes top. I changed it every spring when I was in Boston. Now I do it every 250 hours which is about 3 months.
Run the engine for a few minutes to heat up the fluid, extract the fluid from the dip stick hole, fill with new, run a few minutes again and check the level. Takes about 30 minutes top. I changed it every spring when I was in Boston. Now I do it every 250 hours which is about 3 months.
Thanks Guys, I looked previously but could not find it in my manual. I have the extractor pump, I do not know why I could not extract the transmission fluid with that as I just use that for the oil changes now.
Thanks, BTW I have the M25XPB.
Thanks, BTW I have the M25XPB.
Assuming it's the Hurth trans, if you can get a pan under it, there's a drain plug directly below the dip stick. Draining from the bottom is better, you get all the oil and any debris out. It only holds about 1/2 quart so you only need a small pan. It should be changed often, that trans runs hot and burns the fluid. If you're doing a winter lay up, Hurth recommends filling it to the top with ATF, then draining it back to correct level in the spring. I don't think many actually do that though.
We have the Hurth transmission and we have 400 hours on the engine. We have NO idea if the previous owner ever changed it..SO, we will do that when we change the oil before lay-up tomorrow. Thanks to everyone, I will let you know how it goes!
if you attempt to use the bottom drain, make sure that you CAN screw that drain plug back. usually it requires a couple of extra joints in your hand.
Marek
Marek
Cannot express too strongly how important it is to make sure you are using the correct fluid. I have not seen anything in this thread that confirms that for your make and model you should be using ATF or motor oil or whatever.
Otherwise google self harming and own goal.
Otherwise google self harming and own goal.
John, Alan has a Hurth transmission on his M25 series engine. It uses Dexron ATF, NOT motor oil.
Except you shouldn't do that because it is a crush washer, one time use only. If you do, you need to replace the washer. Consequences: if you don't the fluid could drain out leaving you with a costly repair bill or the need for a complete new transmission.
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My local Ace Hardware has the crush washers. There are also nylon crush washers, which are reusable. You should also check all the fluids before starting every day.
This is no different than the oil drain on a car, and you rarely hear of one with a substantial leak. But there is no "idiot light" for the transmission to warn you of low fluid.
On most boats you can't get under there anyway. I can, so I do.
When I first tried to extract the transmission fluid nothing came out then I noticed I did not have the hose for whatever extractor you are using pushed to the bottom of the Transmission. After I pushed the hose further in no problem. You can go to any auto parts store and buy transmission fluid to the specs of dexron III the newer products exceed this specification. This is what I do whatever amount of fluid I take out I put the same amount in, then check the level and add if needed adding is easier then subtracting. When I take out the fluid I put it in a measuring cup then add the same amount. I use a funnel with a clear hose attached to put it back into the transmission it is not easy to pour it back into the fill hole.
I wrote up a solution for my Hurth model 50 trans. on our M25XP, for our blog on the Ericson site. You might have a similar transmission.
Ours uses 10 fluid oz, and for quite a while I have used synthetic ATF for the annual change. For a washer for that hard-to-reach plug on the bottom, I sourced a "16 mm metric bonded seal". it is a snug and perfect fit over the threads, against the base of the plug. In appearance it looks like a rubber washer material inside a larger diameter alum. washer. You can tighten it down without it being forced out and it cannot be overtightened. A local shop that supplies parts and filters for all sorts of oil products had it, and cheap. Sometimes it pays to find these places that cater to trucking and industrial customers.
Our drain plug can be turned by feel, with a 17 mm wrench, and cannot actually be seen.
Bending a loaf pan and working it under the engine, and then straightening it out works fine for catching the old oil -- when the oil is in the pan, slide it back to the front area where it can be emptied with an old turkey baster.
Remember, if owning a yacht were easy, they'd let anyone own one!
Ours uses 10 fluid oz, and for quite a while I have used synthetic ATF for the annual change. For a washer for that hard-to-reach plug on the bottom, I sourced a "16 mm metric bonded seal". it is a snug and perfect fit over the threads, against the base of the plug. In appearance it looks like a rubber washer material inside a larger diameter alum. washer. You can tighten it down without it being forced out and it cannot be overtightened. A local shop that supplies parts and filters for all sorts of oil products had it, and cheap. Sometimes it pays to find these places that cater to trucking and industrial customers.
Our drain plug can be turned by feel, with a 17 mm wrench, and cannot actually be seen.
Bending a loaf pan and working it under the engine, and then straightening it out works fine for catching the old oil -- when the oil is in the pan, slide it back to the front area where it can be emptied with an old turkey baster.
Remember, if owning a yacht were easy, they'd let anyone own one!
Thanks, with every-ones suggestions I was able to find the Transmission (Changed the fluid from the top) with Dexron IV which exceeds II & III specs. used an extractor and crescent wrench and a Hopkins tool which made it really easy and NOT messy! We have the HURTH transmission! Once I found it and was able to get my hand down in there it was easy!