Right bank issue

[dtcerrato]

Got white smoke (unburnt fuel) and the sound of exhaust making it past an exhaust valve on the right bank. Thought I'd check valve lash first (probably the simplest) then go in through the air box into the liner ports with a probe camera. Removed the valve cover and valve train movement looks normal. When the white smoke first started to appear (return trip from Alaska) it cleared fast upon warming but has gotten progressively worse now with blow by sound and no clearing. Any thoughts?

[Utahclaimjumper]

 Only a compression test will show the problem.>>>Dan

[luvrbus]

What block ?

[dtcerrato]

DD IL 671 Na 4 valve head

[Utahclaimjumper]

 I'm trying to figure out how it can be a "right bank" issue when you only have one "bank" with an inline engine.>>>Dan

[luvrbus]

I'm trying to figure out how it can be a "right bank" issue when you only have one "bank" with an inline engine.>>>Dan

Dual exhaust on the 6L-71 I love the sound of those  

[chessie4905]

Use a if heat gun on each manifold outlet to pin point cylinder. Temp will be degrees lower than others, which should be pretty close.

[luvrbus]

Blow by is going to probably be a head gasket,or valve,I seem to recall somebody called me looking for a head for your bus several months ago.Could be if you changed heads you missed the adjustment on the bridges and burnt a valve 

[chessie4905]

Do you ever run it 1500 rpm or less with full load on grades? That will cause burned valves on them over time with n65's or larger.

[luvrbus]

Do you ever run it 1500 rpm or less with full load on grades? That will cause burned valves on them over time with n65's or larger.

I may be wrong but I think this is the guy that added propane injection and was doing the ETG tests a while back 

[dtcerrato]

Appreciate the responses.

Negative on the lugging, always keep it revved, has never been over 195 (only for short period) since head replacement, mostly runs 180 or cooler.

I like the infrared gun trick on the exhaust manifolds, I'll try that after checking valve clearance.

Yes we're the one with propane injection, dual pyrometers never read above 950 degrees since head replacement (almost 10,000 miles since head replacement).

Propane injection has been helpful on our Alaska road trip, never seen a difference on the pyrometers with or without propane...

We're also the one with blower failure since the head replacement but the smoke issue manifested prior to blower failure, and ran well after blower replacement.

[luvrbus]

The head is coming off anyway then you can tell what happen,I am not a huge fan of propane, for some reason it makes the valve seats pop out on 92 series engines.Bully Dog took a big hit with their system years ago and quit selling the propane injection kit

[dtcerrato]

I've heard the propane pros & cons. We'll find out more and post. My system is "at will" & very little "intermittently". Don't know if it would show in 10,000 miles and other variables of possible causes like excessive downhill speed and blower failure (not all at once)

[luvrbus]

Just toss the friggn propane and turbo your engine and be done with it,Bully Dog and others spent a ton of money trying to build a propane injection system for the 2 stroke and it nearly broke all of them.
You guys come along with 5 gal propane tank and 50 dollar valve and believe you can improve on the system I don't think that is going to happen.
Sorry if it sounds harsh but I just sent out a 8v92 that propane did a real number on and I ask myself why do people buy into to some of this stuff and it ends up costing in the end like $19,000 on the 8v92 but if you are happy with propane it's your call not mine, a turbo is way to go for more power     

[dtcerrato]

We recall lots of uphill where we saved a gear or two &/or needed to downshift farther from the bottom so it really does improve the performance (& diesel mileage).
We're talking about a 53 bus here with 7 to 9 million miles on it running a 69 block that has never been majored.
By the way, we have two 5 gal propane tanks for propane injection besides the four 7 gal for camping and only paid $40 for the valve!
I'd like a turbo but it costs a lot more than $40. No harshness about it, everyone is entitled to their opinions. We look forward to the replies - that's why we're here.
We're the ones that didn't throw the towel in, fixed things as they wore out, and completed our bucket list of 37 years dreaming in an antique that was converted prior to the internet and runs without computer that can sometimes be repaired with tie wire & duct tape... We're probably in a different league but still all bus nuts...