Exhaust cracked?

[SigEpRider]

I’ve been trying to super tune my 1978 Yamaha XS650E. While tracking down a lean condition on the right cylinder, I believe I have found the culprit. Exhaust is pulsing out of the two lower drain holes of the mufflers. After a search of the forum, I believe that no exhaust should be coming out of those drain holes. And if there is, then my mufflers are cracked on the inside.

I just want to confirm as I am about to take off the mufflers to inspect for rust, etc.

I’ve added pictures of the two holes that exhaust is coming out of.

 

[SigEpRider]

Some more details:
1978 XS650E
Tri spark ignition
Carbs cleaned and shaft seals replaced my OldSkoolCarbs
Right side idle screw - 3 turns out
Left side idle screw - 2 turns out
Intake boots replaced with non vacuum port boots
Stock exhaust and headers

 

[SigEpRider]

I think I found the real problem. This is the exhaust gasket take out of the right side. It just fell out. This was not damaged by me trying to pry it out.

 

[Grimly]

Condensate drain holes. Some pipes don't have them, and some pipes rot away quicker than they should.

 

[gggGary]

I think I found the real problem. This is the exhaust gasket take out of the right side. It just fell out. This was not damaged by me trying to pry it out.

Yeah looks like it was pinched Normally the flange should be JUST shy of touching the head flange and gap should be even all around.
They usually end up wedged in there pretty good. A few times I've found two gaskets on one side
Don't think that will cause exhaust to come out of the drain holes.
It's fairly rare but water getting between the inner and outer wall of a stock exhaust has collapsed the inner pipe through repeated freeze thaw cycles.

 

[SigEpRider]

The bike is made the exact same month and year I was born, and it came from Fresno CA area. So we are talking about an exhaust that is 47 years old and original I assume the mufflers could have cracked from the salt water/humidty after so many years.

But, I am correct? Exhaust gas should not be coming out of the drain holes at the bottom of the mufflers?

 

[SigEpRider]

Well….if I have to replace the mufflers, can y’all give me some suggestions of what to replace them with?

Slip ons? Full exhaust (delkevic)?

Keep in mind I am no where near a carb tuning expert and not good at jetting at all

 

[gggGary]

if they look/sound good yet a bit of internal corrosion, leakage out the drains not a deal breaker?
that's not where you'll find the answer to your rh cylinder lean issue.

 

[Its been a long time]

if they look/sound good yet a bit of internal corrosion, leakage out the drains not a deal breaker?
that's not where you'll find the answer to your rh cylinder lean issue.

Correct. If anything, different mufflers are probably going to make that worse.

 

[AUTOMAN]

Should the exhaust come out of drain holes> YES!
Very little unless tailpiece is plugged.

Holes let acidic condensate to exit the low spots inside of assembly.

cliff

p.s. look at any muffler on any car

as for lean condition NO!

 

[SigEpRider]

Thanks for the help.

The mufflers are in perfect shape aside from maybe being cracked inside. When I removed them, not rust or debris came out of them. Looked down the pipe and couldn’t see any cracks (don’t know if I would). From the sound of it the exhaust coming out of the drain holes may be normal.

I’m gonna put new exhaust gaskets on and reinstall. See if that helps my lean mixture on the right side. After all we can all free that gasket was toast. Then I’ll keep digging into what might be causing a lean mixture. If anything, I figured I can always seal off the holes with some screws and see if that is a cause also.

 

[AUTOMAN]

From the posts you are using o2 sensors.

 

[SigEpRider]

From the posts you are using o2 sensors.

Negative on o2 sensors.