News:

Mat Oxley 1986 IOM TT


click above to read more about Mat.

Main Menu

Update: RD 400 Smoke from 1 Exhaust

Started by Milan, September 19, 2022, 04:54:19 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Milan

Being a novice at this I thought i would ask to get a direction for a fix.

Got an RD400G with DG pipes
Started it up, both pipes smoke.
Idles & runs good

After warmup, the right side smokes. left is barley visible.

I think bike had sat for a long period.
So did 2T oil leak in, Seal gone?

I have not had time to look at the plugs.

M

teazer

I would expect the left seal to suck air in from behind the alternator and the right one to suck in oil from the primary gears/clutch.

First thing to do is a leakdown test and listen for air leaks as the gauge drops.

m in sc

if crank seal age is unknown, change them.  :twocents:

Hawaii-Mike

Yup right side smoking heavily probably means the crank seal is no longer sealing.  Transmission oil getting sucked into the cylinder.

Milan

This may be a stupid question.

But why would oil not get sucked into both cylinders, if the lower chamber is open to both?

Or is it just because that one is closer?

M

Striker1423

The right side is bathed in oil (clutch side), the left side is open to air (points/cdi side). Just because the lab seal is open to both sides doesn't mean the oil will migrate all the way over.

m in sc

Quote from: Striker1423 on September 20, 2022, 09:52:34 AM
The right side is bathed in oil (clutch side), the left side is open to air (points/cdi side). Just because the lab seal is open to both sides doesn't mean the oil will migrate all the way over.

exactly. the clutch side is smoking more.

Milan

OK,

ordered a new seal.

Any other posts here on its removal.

I took the primary gear off the KH250.
So I assume its the same.
The seal was right there.

So just pry it out?

m

m in sc

no, you need to split the cases, there's a retainer lip on the seal. do both sides, not just one. if the RH one is leaking, for sure the LH one is or very soon will be.. 

Milan

I was hoping you would not say that.

I am very mechanically inclined.
But do not think I want to split the cases myself.
Never done any

I would have to make room in my garage and it would take me weeks to do.

M

m in sc

its a weekend job. rip the band-aid off and get in there. might as well get a complete seal kit.  :twocents:


Hawaii-Mike

If you want to experiment, maybe you can pull the clutch-side seal out with a wood screw.  Then cut the ridge off the new seal with a razor blade and gently press it in.  Apply engine sealant around the perimeter of the seal before pushing it in.

Kawasaki triples don't have the ridge but it's a common way of replacing seals, not requiring splitting the cases.

Milan

I have seen a video of that, pulling out with a screw.
That's what I was hoping for.

M

Striker1423

not impossible, but its a weekend fix as they say for snowmobilers. I'd service the whole engine over the winter after the season was up though.

m in sc

since you covet this thing so much, just do it correctly. Not like you need it to go to work. Just my .02