Transmission oil changes

[Steve Laume]

While at the Mystic Wooden Boat Show this past weekend, I talked to the Universal engine rep about a few things. I was a bit shocked to learn that he strongly recommended changing the transmission oil every 20 hours. I have been changing it whenever I change engine oil which is certainly not every 20 hours. He stressed this point so it must be pretty valid.

This got me to thinking that there must be a better way to go about doing this if it is to be done on a regular basis. I already had the clutch plates in my transmission replaced once and it requires pulling the engine to do so. This is not something I want to repeat. Has anyone tried using a turkey baster with an extension tube to suck the trans fluid out? What about a large syringe? That would have the advantage of also being able to meter how much fluid was removed and replace it with the same amount by refilling the syringe with clean fluid and injecting it back into the trans.

Just wondering if anyone is changing fluid at 20 hour intervals and if you have found an easy way to do it, Steve.

[David van den Burgh]

I use our Tempo Oil Boy fluid extractor for engine and trans. Very convenient!

Every 20hrs?! Wow. Nope. Every season here in Michigan.

[abreece]

Same as David.

I change the transmission fluid every season (per my engine manual).

I can't make any sense of changing the fluid every 20 hours - perhaps he accidentally left off a "zero" (should be 200 hrs.?)?

Sorry we didn't run into each other at the show, glad the rain held off.

Very Best,
Andrew

[Steve Laume]

It was a nice day at the show on Sat. The reason it didn't rain is that I carried my rain gear in my back pack all day and you are welcome.

The 20 hours was not a miss speak as he repeated it at least twice. I was thinking that I would have needed a trans oil change twice on my trip last summer if I was to follow his advice. I think the point here is that we need to have a quick and convenient way of changing the fluid at least a bit more often than is common. I also have a feeling that there are transmissions out there with fluid in them that is decades old and they are still operating. That might be luck and a major disaster in the making.

I do have a vacuum tank extractor for removing oil but it is a bit of over kill for the trans and kind of a pain to get back in there. That is why I was thinking a large syringe might make an easier job of it. The easier it is the more likely I am to do it more often, Steve.

[David van den Burgh]

Maybe you just need a longer tube. I had to replace the supplied tubing with a length of polyethylene tubing, which is long enough that I don't have to have the extractor right next to the source. Works easily enough. You're right, though, that there's not much to extract in those transmissions. Maybe just a small, handheld fluid extractor/pump would be the thing?

[Steve Darwin]

The Yanmar service manual (1GM, 2GM, and 3GM) says to change engine crankcase oil every 100 hours, every 250 hours for the clutch case oil.

[Steve Laume]

I think maybe the engine rep was on drugs that day. http://www.foleyengines.com/resources/t ... ic-service

I would still like to find an easier way to change out the oil but at least I don't feel like I have been abusing my poor little transmission, Steve.

[Maine Sail]

While at the Mystic Wooden Boat Show this past weekend, I talked to the Universal engine rep about a few things. I was a bit shocked to learn that he strongly recommended changing the transmission oil every 20 hours. I have been changing it whenever I change engine oil which is certainly not every 20 hours. He stressed this point so it must be pretty valid.

This got me to thinking that there must be a better way to go about doing this if it is to be done on a regular basis. I already had the clutch plates in my transmission replaced once and it requires pulling the engine to do so. This is not something I want to repeat. Has anyone tried using a turkey baster with an extension tube to suck the trans fluid out? What about a large syringe? That would have the advantage of also being able to meter how much fluid was removed and replace it with the same amount by refilling the syringe with clean fluid and injecting it back into the trans.

Just wondering if anyone is changing fluid at 20 hour intervals and if you have found an easy way to do it, Steve.

20 hours is probably a tad overkill on a Hurth ZF but not crazy. I do it twice per season with my ZF v-drive (engine has approx 4000 hours). I've seen far too many of these Hurth/ZF boxes needing rebuild due to dirty fluid and lack of maintenance.

The worst thing you can do is to accidentally leave the gear in forward when sailing. If you do change the fluid ASAP..

Some things that may help I put a magnet drain screw into mine to pick up any metallic bits. As of yet nothing. I also suck it out via the extractor then open the drain screw to get the very bottom of the sump. I just drain it into a 1 gallon Ziplock with an oil absorbing pad in it.

My two changes run me about $6.00 per year but my box takes an entire quart.. A new gear would run me about 4k.....

[David van den Burgh]

My two changes run me about $6.00 per year but my box takes an entire quart.. A new gear would run me about 4k.....

Well, when you put it that way...

[Neil Gordon]

Did the rep try to sell you a case of transmission oil at the same time?

[John Danicic]

On Mariah, I change the tranny fluid once a year along with the engine oil at take out. The PO included a Jabsco oil Changing pump in the sale though rather top heavy and messy if tipped over, it is very effective for both the engine and the transmission oil.



It has a long, flexible 1/4 inch pipe that you insert into the transmission filler/dipstick and it effectively sucks out all the oil in booth locations. For the tranny, I always put in the required, just a bit less then 1/2 a quart, (.44Qt) of Synthetic ATF fluid. So far so good at about 1900 hrs.

I ran a Toyota Camry for over two hundred thousand miles and never in the 22 years I owner it changed the transmission fluid. It never seemed to mind.

But boats aren't cars and cars aren't boats and we do treat them differently do we not?