Jump to content

Drz 400 oil dumping in the air box

Recommended Posts

So my drz 400 has been having a minor problem. It smokes horribly and it’s not the head gasket my radiator fluid levels are normal. After two minutes of riding the bike will bog down to like 20 mph and the biggest smoke cloud you’ve ever seen comes out of the exhaust. And all the oil is going through the air box and not like a few drops like glasses full it’s ridiculous honestly! It has a stock breather box and I think all my hoses are going to where they should be. Could it be the breather box is clogged or the oil screen in the frame is clogged or bad valve seal which I don’t think it is they have less than 200 miles on them. I don’t think it’s blow by from the piston rings either they are fairly new also and I think it’s just too much oil coming through for it to be that. Any ideas or suggesting would be very helpful thank you.

Share this post


Link to post
Share on other sites

Compression test time/leak down test. Only one reason for excess blow by that comes to mind. Bad rings

Did you take the radiator cap off and run it, just curious.

You can test to see if the breather box is clogged by blowing thru it, but it sounds like its not clogged

Edited by rustynut2
  • Like 1

Share this post


Link to post
Share on other sites
Compression test time/leak down test. Only one reason for excess blow by that comes to mind. Bad rings
Did you take the radiator cap off and run it, just curious.
You can test to see if the breather box is clogged by blowing thru it, but it sounds like its not clogged

No I haven’t ran it with the radiator cap off, and I will do a compression test later on today and let you know what it says and I’ll test the breather box too and update you.

Share this post


Link to post
Share on other sites
Compression test time/leak down test. Only one reason for excess blow by that comes to mind. Bad rings
Did you take the radiator cap off and run it, just curious.
You can test to see if the breather box is clogged by blowing thru it, but it sounds like its not clogged

No I haven’t ran it with the radiator cap off, and I will do a compression test later on today and let you know what it says and I’ll test the breather box too and update you.
Glasses? Drain the oil and measure how much comes out.

Only about 1 quart came out

Share this post


Link to post
Share on other sites

I gotta say....this really sounds like overfull oil: have you been following the correct procedure to check the oil level?  You have to run it for over 3 minutes, then shut it off and wait a short period, and then check the level.  If you check it cold and top it up it will be way overfull.  

Share this post


Link to post
Share on other sites

So the guys want to make sure you drained the frame and engine both.  I’m still guessing bad overhaul, you said it was recent correct.  

 

Share this post


Link to post
Share on other sites
You drained the engine and the frame????

Yes and only about 1 quart came out
I gotta say....this really sounds like overfull oil: have you been following the correct procedure to check the oil level?  You have to run it for over 3 minutes, then shut it off and wait a short period, and then check the level.  If you check it cold and top it up it will be way overfull.  

But would that make my compression go to 45 psi ?

Share this post


Link to post
Share on other sites
5 hours ago, Johnnyboy2b4 said:


Yes and only about 1 quart came out
But would that make my compression go to 45 psi ?

Oil screen on the frame is clean? Oil filter in right? No debris when you  drained the oil?

Low compression is normal on a machine with auto decomp. It will be even lower if the battery is not 100%.

Share this post


Link to post
Share on other sites

To be clear: I remain very convinced that you had too much oil in the machine.  You have not clarified how you emptied the oil to measure it...but if you only pulled the drain plug out of the bottom of the engine, then you only drained the sump, which contains only a small part of the oil.  The rest of the oil is contained in the frame, and has to be drained in a completely different way.  

Similarly, this "dry sump" system has a very specific process that MUST be followed to verify the oil level.  If you simply pull the dipstick out without running the bike, it will very likely read very low, and MANY owners have subsequently added oil, overfilling the system with the result that oil is forced into the breather system, drips all over, and gets burned with a blue smoke.

You have not posted any response to let us know how you checked the oil level, nor how you drained it.

Start with the simplest solution.  

WRT compression test: with the auto decompressor you will get a low reading...this is normal.  This is to allow the starter to have a chance to crank that big thumper over.

Please post you oil check and oil drain process so we can provide further advice, if it is required.

Share this post


Link to post
Share on other sites
To be clear: I remain very convinced that you had too much oil in the machine.  You have not clarified how you emptied the oil to measure it...but if you only pulled the drain plug out of the bottom of the engine, then you only drained the sump, which contains only a small part of the oil.  The rest of the oil is contained in the frame, and has to be drained in a completely different way.  
Similarly, this "dry sump" system has a very specific process that MUST be followed to verify the oil level.  If you simply pull the dipstick out without running the bike, it will very likely read very low, and MANY owners have subsequently added oil, overfilling the system with the result that oil is forced into the breather system, drips all over, and gets burned with a blue smoke.
You have not posted any response to let us know how you checked the oil level, nor how you drained it.
Start with the simplest solution.  
WRT compression test: with the auto decompressor you will get a low reading...this is normal.  This is to allow the starter to have a chance to crank that big thumper over.
Please post you oil check and oil drain process so we can provide further advice, if it is required.
i drained the frame bolt, and the engine drain bolt, the engine drain bolt had excessive amount of metal shavings and so did the oil filter. Also took the bolt with the screen on it out and found more metal shavings. Only one quart came out at the most. I took the spark plug out and cranked the bike over and oil was coming out of the spark plug socket. I have since than took the head off. And I saw light scratches in the cylinder and found one of the cam caps were cracked. So I’m just parting out the motor on eBay and buying a new one as I am to lazy to fix it at this point.

Share this post


Link to post
Share on other sites

Thanks for letting us know the end of the story.  So the top end went and this allowed oil into the cylinder etc.  

Share this post


Link to post
Share on other sites
Thanks for letting us know the end of the story.  So the top end went and this allowed oil into the cylinder etc.  

Yeah, not what I was hoping for though.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×
×
  • Create New...