Lots of white smoke and poor performance. PLEASE READ!!!!!!

[jasonsdad]

I am new to blasters well 2-stroke in general but I do think of myself as a good 4-stroke mechanic since we run ltr450s but trying to fix this quad for a friends son that his dad is no longer around.

He was riding it and started smoking white smoke bad and died and would not start. I put new plug in it and still wouldn't run it would start rev up and die.

I have read enough to know that the general cause of this is the crank seal on the clutch side. So I changed it out and now it will run and still smokes white but will run decent. But still not like it should and will not idle.

We are going to have a nice weekend and I would like to take him to ride with my son and I but I am lost at what to do next.

More info on the quad it is a 04, had oil injection removed, I put a top end on it back about 2 years ago and has a lot of time on it.

Is there anyway that it could be the top end? If not what could it be?

 

[Whitty21]

sounds like you are leaking between the case halves and burning tranny fluid, your best bet would be to make/buy a leakdown tester and find that leak

 

[jasonsdad]

Don't want to sound stupid but how would you do a leak down on a 2-stroke with no valve to keep exhaust from leaking.

The crank seal on the clutch side really helped the smoke is there a certain way that the metal bushing goes in it looked the same on both sides to me.

 

[jasonsdad]

I was thinking that it might have still been some oil in it from the seal but I let it run for 10-15 min and still smoking

 

[hudack]

you get a expasion plug or some ruber and a piece of metal over the exhaust port

 

[super noober]

http://www.blasterforum.com/do-yourself-20/build-use-leakdown-tester-10663/

there ya go dude, good luck man

 

[jasonsdad]

Off to Lowes. I have a couple of questions.

First how many lbs of air should I use.

Also if it is between the cases how will I find that.

 

[Whitty21]

5lbs of air, and the leak will come out of the tranny vent if its between the cases

 

[super noober]

Off to Lowes. I have a couple of questions.

First how many lbs of air should I use.

Also if it is between the cases how will I find that.

the leak will show up with soapy water just like a tire. and only use 6 or 7 lbs of air with a HAND PUMP a compresor will blow all ur seals out lol

 

[jasonsdad]

Thanks I am headed to get what I need. I hope I can pull this off today and get this going for him.

 

[super noober]

Thanks I am headed to get what I need. I hope I can pull this off today and get this going for him.

well we will be here lol

 

[slickerthanyou]

Where ya live at?

 

[YFS101]

yep it should hold 6-7psi for 10 minutes or more.

whenever you replace the seal on the right side you should replace the bushing.

 

[Braaaptor]

^^Very true. And use OEM Yamaha seals. Most aftermarket ones are of questionable quality.

 

[Blaner]

^^Very true. And use OEM Yamaha seals. Most aftermarket ones are of questionable quality.

agreed i dont risk any others

 

[jasonsdad]

It was a hot rods seal kit and I still can't find a problem. Pumped it up to 7lbs and 15min later it had over 5lbs. This thing is driving me nuts. I am from Oklahoma.

 

[StrokedTater244]

if it has alot of tranny oil in the crank case it might just take a little more time to blow it all out. now that you are sure there is no air leak and is not running too lean you can run it a bit and try to burn all the tranny oil out.

 

[jasonsdad]

If the rain stops today I am going to have my son ride the thing till it fixes itself or blows up. I let the neighbor kid ride my son's ltz400 this weekend and it was way to much quad for him so I have to get this thing going.

 

[ruthless_one3k]

If it was leaking around the crank seal maybe it is possible that tranny oil has built up in the exhaust and is still burning off:-/ good luck

 

[Blaner]

it may be a slow leak between tans and crankcase and as it stands the oil seeps in. if its very small, a leak test would show a slow decrease, perhaps that is what you are experiencing, since your pressure did go down somewhat, im not sure, this is abit baffling