Oil Change Question WR400

Does anyone actually crack the banjo bolt open on the oil-pipe that connects to the cylinder head when doing an oil change as the manual states? I never noticed this was even in there. I only am aware of it because the bike I just bought leaks from the crush washer and the PO told me it says to do this when changing the oil. I can't remember if it is in my YZ250f manual or not. Thanks in advance for the info.

I do it at every oil change. It is for ensuring that you have oil pressure, and that oil is getting to the head. It gives me piece of mind to know that I have no blockages in my oil lines, screen, ect. I strongly recommend doing it. It only takes a minute. After changing the oil, start the bike up, and crack the bango bolt. If you don't see oil seeping from it shortly after, shut the bike off, and check your oil lines, oil screen, and ect...

Edited by mikewrf18

I realize how much I sound like a newbie here. I just checked in my YZ250F manual and don't see that as part of the procedure, so something must be different, either in Yamaha's minds or in the design. In any case, I do plan to do it for the 400. I need to get some new crush washers though, I cant get those damn things to seal. Must be past their limit, imagine that, after 13 years...

Thanks for the info :thumbsup:

every time!!! takes what 2 seconds, plus same size wrench as drain bolts

I found this on thumperfaq.com

Quote: Test for oil pressure using the indicating bolt on the right hand side of the engine block (see owner’s service manual).

It must be in your manual, if you have the factory service manual. I know it was in my manual for my 02' YZ250F. All the yamaha's I've owned have had a spot to check for oil pressure.

Ah, yep, you were right Mike. It is in the 05 250f manual, one page past where I looked. I like the newer design better, there is a bolt next the the banjo bolt just for checking. Probably to eliminate having to re-tighten the banjo bolt all the time. In any case, I am changing my oil change habits and will check it on both bikes.

Own two W400s. I cracked that bolt once on one of the bikes many, many, many moons ago and haven't done it since. YMMV.

Be careful how much torque you put on the bolt as it's lubricated with oil and you can easily over torque and strip it.

Ah, yep, you were right Mike. It is in the 05 250f manual, one page past where I looked. I like the newer design better, there is a bolt next the the banjo bolt just for checking. Probably to eliminate having to re-tighten the banjo bolt all the time. In any case, I am changing my oil change habits and will check it on both bikes.

Glad you found it. Checking pressure after oil change gives me piece of mind, knowing the oil is getting where it needs to.

Given that there is virtually nothing that you could do during the course of a normal oil change that would prevent the oiling system from delivering oil, I see no reason to do this except on an occasional basis as a general check on things. After an oil change is as good a time as any, but so is any other time.

But rather than disturb the banjo fittings, which can be prone to cracking at their joint with the oil manifold tubing, see if your engine does not also have a small hex plug somewhere on the head with a copper washer under it that can serve the same purpose.

But rather than disturb the banjo fittings, which can be prone to cracking at their joint with the oil manifold tubing, see if your engine does not also have a small hex plug somewhere on the head with a copper washer under it that can serve the same purpose.

Great advice, I had never thought of that! :cheers:

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