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Little white smoke on startup for 15-30 seconds

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So my 05 drz400sm smokes a little from cold. It stops about 15 to 30 seconds after it starts and I just changed all my hoses so they are hard and I'm not sure how much pressure should be there when running. I just changed coolant at the same time. My questions are how much pressure should be in the cooling system. It seems to even have a small amount when cold. I can not comment on the level changing as I have not rode it enough yet. And about the smoke... My nose is not the best these days ( afrin) lol but it does not seem to smell sweet at all... mods are 440 kit for 39mm slant, yoshi rs2 3x3 etc. Im sure this may have been covered but im getting no where. Any help is appreciated.. I have heard of a few 440 kits doing this also so I'm not 100 percent on this. My  new overflow res. I installed with hoses  has got 3/4 of an inch in it after some idling and short ride and has not gone up or back to rad.. thanks for any help.....

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How many miles?

The big bore is not the reason.

Are you sure it's white and not blue smoke? Smoke on start up is a sign of a leaky valve seal.

I don't know what the operating pressure normal is but the cap's release pressure is 13.5-17 psi.

The test for the coolant system is it should hold 17psi for at least 10 seconds.

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14 minutes ago, ohiodrz400sm said:

How many miles?

The big bore is not the reason.

Are you sure it's white and not blue smoke? Smoke on start up is a sign of a leaky valve seal.

I don't know what the operating pressure normal is but the cap's release pressure is 13.5-17 psi.

The test for the coolant system is it should hold 17psi for at least 10 seconds.

Well according to the old owner about 800 miles on top. New bearings and original crank was checked and tight so I'm told. To make it to the res my radiator cap must still be good. It did look like bubbles when it was being pushed in idleing but it may be normal. And it def looks white to me. Also i let it cool off for 20 min and poped the cap. There was pressure still but I started it with the cap off and let it idle for 30 to 40 seconds and there was no bubbling in the rad at all.. was told to check for bubbles when it's running in rad. It the bubbling into res look normal. Prob a dumb question but I want to ride it not work on it. Other than this problem it seems to run good other than a lean bog or something my slant body has.. It's temperamental. Thanks for the help I really appreciate it...

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I just realized who's helping me AGAIN... thank you Ohio drz you are always helping me out with my new bike problema lol. I appreciate it big-time 

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So I further inspected it all last night and I get get bubbles in rad on higher revs very small and quite a few. I must have a bed head gasket and have a pin hole leak and it slowly builds pressure. Also a few when hot in the overflow. Can anyone tell me that's prob the culprit before I order a gasket and tear it down Sunday and get parts orderd. No discoler in coolant it's as green as can be.. have not drained crankcase yet but just pure oil on dip stick In the frame. But I'm assuming pinhole blowby somewhere.level in tank is barley above where it widens and gets bigger toward the bottom. About 1,5 inchs up but I feel it would slowly keep filling. This the amount I got after about 20 min run time but it also did not suck back into the radiator. Everyone agree??? Headgasket???

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Also.... coat headgasket or no on drz i have heard both ways so id rather ask. Perma tex copper spray is it called correct. Want to buy the right one if that's what is recommended to do for install... thanks to all who are helping me out...

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1 hour ago, Craigo said:

HG issues would be the way I read it....

This is what I am thinking as well.... should it be coated lightly ? And what should I use the permatex copper spray?

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This is what I am thinking as well.... should it be coated lightly ? And what should I use the permatex copper spray?


If the mating surfaces are flat and smooth it shouldn't be needed. I made the choice not to use it and haven't had any issue.

What you NEED to be aware of while changing the head gasket are the rivets in the head gasket. The gasket is laminated(don't run a single layer) and sometimes the rear rivet can interfere. If you see ANY rivet that is between the cylinder and head(even partially) it must be removed. To remove the rivet all you need to do is clip the head off with diagonal cutters.
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I figured it was not needed but was unsure because I thought everyone was stick on using it for this bike. Will try and find a flat surface to check head on regardless. Thanks again for the reply ohiodrz. Also would it be smart to buy a top end gasket kit as opposed to just a head gasket in case? Brand of gaskets? Cosmetic or oem?

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I ended up ordering the cosmetic 94mm big bore top end gasket kit and permatex spray a gasket copper... Someone convince me..... Do I use it or not... Also just curious l, I can just unlit my head pipe and let it hang correct??? I ask because head pipe and mid pipe a re like fused together lol so the pipe will have to hang there or be cut and buy a new head pipe witch I plan to in few weeks but need tires first and a sticker so I would rather wait so I can ride.   It looks like it will be fine to hang tho...i just took it out completely last time me and a buddy did a bb kit in a drz. Mine already had it So was wondering before I tear in after work today or tomorrow in the am. Then it is wait for parts and get on the road finaly!!!!

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13 minutes ago, ohiodrz400sm said:

The pipe will come apart, it's just stuck. Use a little never sieze when you slip it back together

What can I do to help it along. Either I'm a &%$#@! or it is very very stuck prob been on since 2005_2007 lol. I did use never cease on mid-pipe to muffler connection and even that was very stuck but with a little help from my rubber mallet it came off but took a few min to do for sure... Will a propane torch help with a little heat maybe? Anyone ever have this issue.. I have not because I always use never cease at the joints...

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9 hours ago, Diesel0889 said:

This is what I am thinking as well.... should it be coated lightly ? And what should I use the permatex copper spray?

Not needed with 440 bore...any bigger and I would say yes for sure

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