Yamaha TRX850 Enthusiasts Forum

I'm changing the oil on my TRX and wonder how much oil should be in the sump? I found over a pint and gather with a dry sump there should only be about quarter of a pint. Can anyone help?

Hi Bluto

There are just over 4 litres in there.

There are also 2 drain plugs. One on the right side of the engine and one on the left.

Hope this helps.

Cheers, Andy.

Hi & Welcome Bluto,

Andy's right. You'll find quite a few variations to what the capacity specs should be. Just beware of going by the sight window as the fresh-fill indicator, as results can vary more than you'd want. I've done it that way before and it was fine one time, then overflowing from the filler at about 3.5 litres the next, then barely showing at 5.5 litres the time after that! (I drained it back of course).

Basically, the TRX can be a bit of a princess with oil; 1. Fill - ride - check... 2. Topup (if nec.) - ride - check again. 3. Check every 1000k's at least, especially if giving it some.

Bluto wrote:I'm changing the oil on my TRX and wonder how much oil should be in the sump? I found over a pint and gather with a dry sump there should only be about quarter of a pint. Can anyone help?

About 500mm is correct in the lower sump via the larger bottom end sump bung. This bung just drains oil from the motor itself not the dry sump sitting on top of the motor. There is a non return valve that uses a seal with a ball and spring that stops oil draining from your dry sump down into the motor when the motor is stopped.
Parts 29..30..31
Keep in mind, If ever doing a rebuild a definate to spend a couple of dollars and replace this seal and clean the gauze filter inside the dry sump too.
http://www.toptwo.com.au/oem-parts

Thanks for replying. I'm trying to decide if I need to remove sump cover to check gauze filter and pressure relief valve. The manual (Haynes) doesn't say how much oil should be in there when you remove the crankcase drain plug (on left hand side of engine). A pint seems excessive in what is supposed to be a 'dry sump' engine-hence my confusion.

I tend to always measure what comes out, then put the same amount back in as a starting point. I then check it on the sight glass straight after a 10 min ride. It pays to be careful on this as secondhand good engines are like hens teeth these days.