Took the GMC (73 Sequoia 260) on it's longest cruise yet (about 200 miles
roundtruip) just to check out all the work I've done on it lately. Ran great!
A/C
worked great! Stopped to get gas and a bunch of high school kids came over
oohing and ahhing, peeking in the windows.
Only negative about this little cruise was we decided to see how well
ventilation is w/o A/C. So I cracked the rear overhead vent about an inch, the
front overhead vent about the same, and we had the side window behind the driver
open about a foot. It seemed at a certain
speed (60 mph, wouldn't you know) there was a strong smell of exhaust. Seemed
to be filling up the coach starting from the rear.
With all windows closed and A/C (overhead unit and dash) didn't have the
problem.
Obviously checked the exhaust system. There were some leaks in the last three
feet of pipe. One hole about the size of a dime where the
exhaust pipe passes thru the frame, one nickel size at the 90' bend by the rear
bumper and a pinhole a little downstream of this.
I also noticed the two mufflers each have four drain holes. One where you might
expect one, but one above this symetrical (if you flipped the muffler over, the
hole would be where you would expect it), and two on the other end (inlet side)
in the same configuration as the outlet side. So for the two mufflers, that
makes a total of 8 drain holes. These where purposely drilled, not rust holes
as the mufflers look fairly new as does the exhaust piping. No other leaks
including exhaust manifolds and donuts.
I will get the rear pipe fixed but I was wondering if the drain holes were
letting exhaust in thru the side window. Also
I would guess you should never have the rear most windows open while driving,
but have others found exhaust smells are normal in these coaches? Is it alright
to crack the overhead vents while driving? This newby needs to know!
Thanks
eric.henning
73 sequoia 260
roundtruip) just to check out all the work I've done on it lately. Ran great!
A/C
worked great! Stopped to get gas and a bunch of high school kids came over
oohing and ahhing, peeking in the windows.
Only negative about this little cruise was we decided to see how well
ventilation is w/o A/C. So I cracked the rear overhead vent about an inch, the
front overhead vent about the same, and we had the side window behind the driver
open about a foot. It seemed at a certain
speed (60 mph, wouldn't you know) there was a strong smell of exhaust. Seemed
to be filling up the coach starting from the rear.
With all windows closed and A/C (overhead unit and dash) didn't have the
problem.
Obviously checked the exhaust system. There were some leaks in the last three
feet of pipe. One hole about the size of a dime where the
exhaust pipe passes thru the frame, one nickel size at the 90' bend by the rear
bumper and a pinhole a little downstream of this.
I also noticed the two mufflers each have four drain holes. One where you might
expect one, but one above this symetrical (if you flipped the muffler over, the
hole would be where you would expect it), and two on the other end (inlet side)
in the same configuration as the outlet side. So for the two mufflers, that
makes a total of 8 drain holes. These where purposely drilled, not rust holes
as the mufflers look fairly new as does the exhaust piping. No other leaks
including exhaust manifolds and donuts.
I will get the rear pipe fixed but I was wondering if the drain holes were
letting exhaust in thru the side window. Also
I would guess you should never have the rear most windows open while driving,
but have others found exhaust smells are normal in these coaches? Is it alright
to crack the overhead vents while driving? This newby needs to know!
Thanks
eric.henning
73 sequoia 260
