Went to Chicago on Saturday, then back on Sunday morning for a parade this
afternoon. Anyway, it was hot both days.
I have the correct temp sender (TS-6469). Most of the time, the pointer is
just under the 1/2 mark. I have the 2705/7 clutch, the small stamped water
impeller, a 2 year old radiator on a 403, all stock, rebuilt distributor,
new timing chain, etc.
On our last trip, I hadn't heard the fan once during the whole trip. I had
gotten a 2747 that I was getting ready to put on Friday night. Side note to
this posting: I have a checklist I use before we take a trip. So does my
wife. Here's part of her list:
1). Have you changed anything on the GMC since our last trip, if so, what
and when?
2). Has it been tested on a short trip before we leave Indiana?
Of course, the 2747 wouldn't pass item 1 or 2, so it was put on a "scheduled
hold" much like NASA. I was grousing around, worried about the whole thing.
Anyway, the 2747 went in the closet, not under the hood.
We had no problem going to or driving around the Chicagoland area, but the
temp pointer was more on the 1/2 mark than usual. Never heard the fan clutch
engage. We had the A/C on regular, not max, and were quite comfortable. On
high A/C fan, I could get the veranda/pilot's area below comfort to 65
degrees. (I was wearing shorts, too cold on my legs.) I kept the fan on 3/4
setting and was happy. The A/C clutch/belt took more wear and tear, I could
hear the belt chirp when the clutch would re-engage at highway speeds.
Driving around town, no roar, and the temp pointer was right on the 1/2
mark. A/C still worked fine, but I switched to MAX to keep the 9 occupants
cool in the back. (we also ran the Onan and rear A/C part of the time to
keep the coach 'chilled' while running errands.) A bank sign in Crestwood
showed 96 degrees.
One little hiccup going up a hill in Orland Park, we'd sat at a construction
tie up for about 20 minutes, then taken off. Almost like a vapor lock type
of condition, but just two little hiccups and we were over the crest of the
hill and had picked up 30~40 mph of speed. I downshifted to 2nd and we were
coasting to the next light. Like Larry says, pucker factor on high, but the
problem went away. Got to thinking about Arch's
'stand-by-your-electric-fuel-pump-switches men' solution for a minute
though.
Driving back on Sunday morning, we were a little pressed for time and
followed a state trooper (at an appropriate distance) in no traffic from the
IN/IL state line to Plymouth, IN on US 30. At that speed, the temp gauge was
about 1/2 a needle width above the 1/2 mark. BTW, it was 88 degrees on the
trip back in the cool of the morning, if there is such a thing. From
Plymouth home at more 'civilian' speeds, the needle was a full width below
the 1/2 way mark.
Bottom line -- about 320 miles round trip, 38 miles city driving, looks like
8.1 mpg overall.
Now, I'll change the fan clutch and see what I think the next time out. I
doubt it will be so stinkin' hot, so it'll for sure be better.
I don't think we had the good solid cold A/C I'd like driving in town
because the fan clutch was to lazy moving enough air, and I think that the
temps were higher than I'd like on the highway for the same reason.
Mark
afternoon. Anyway, it was hot both days.
I have the correct temp sender (TS-6469). Most of the time, the pointer is
just under the 1/2 mark. I have the 2705/7 clutch, the small stamped water
impeller, a 2 year old radiator on a 403, all stock, rebuilt distributor,
new timing chain, etc.
On our last trip, I hadn't heard the fan once during the whole trip. I had
gotten a 2747 that I was getting ready to put on Friday night. Side note to
this posting: I have a checklist I use before we take a trip. So does my
wife. Here's part of her list:
1). Have you changed anything on the GMC since our last trip, if so, what
and when?
2). Has it been tested on a short trip before we leave Indiana?
Of course, the 2747 wouldn't pass item 1 or 2, so it was put on a "scheduled
hold" much like NASA. I was grousing around, worried about the whole thing.
Anyway, the 2747 went in the closet, not under the hood.
We had no problem going to or driving around the Chicagoland area, but the
temp pointer was more on the 1/2 mark than usual. Never heard the fan clutch
engage. We had the A/C on regular, not max, and were quite comfortable. On
high A/C fan, I could get the veranda/pilot's area below comfort to 65
degrees. (I was wearing shorts, too cold on my legs.) I kept the fan on 3/4
setting and was happy. The A/C clutch/belt took more wear and tear, I could
hear the belt chirp when the clutch would re-engage at highway speeds.
Driving around town, no roar, and the temp pointer was right on the 1/2
mark. A/C still worked fine, but I switched to MAX to keep the 9 occupants
cool in the back. (we also ran the Onan and rear A/C part of the time to
keep the coach 'chilled' while running errands.) A bank sign in Crestwood
showed 96 degrees.
One little hiccup going up a hill in Orland Park, we'd sat at a construction
tie up for about 20 minutes, then taken off. Almost like a vapor lock type
of condition, but just two little hiccups and we were over the crest of the
hill and had picked up 30~40 mph of speed. I downshifted to 2nd and we were
coasting to the next light. Like Larry says, pucker factor on high, but the
problem went away. Got to thinking about Arch's
'stand-by-your-electric-fuel-pump-switches men' solution for a minute
though.
Driving back on Sunday morning, we were a little pressed for time and
followed a state trooper (at an appropriate distance) in no traffic from the
IN/IL state line to Plymouth, IN on US 30. At that speed, the temp gauge was
about 1/2 a needle width above the 1/2 mark. BTW, it was 88 degrees on the
trip back in the cool of the morning, if there is such a thing. From
Plymouth home at more 'civilian' speeds, the needle was a full width below
the 1/2 way mark.
Bottom line -- about 320 miles round trip, 38 miles city driving, looks like
8.1 mpg overall.
Now, I'll change the fan clutch and see what I think the next time out. I
doubt it will be so stinkin' hot, so it'll for sure be better.
I don't think we had the good solid cold A/C I'd like driving in town
because the fan clutch was to lazy moving enough air, and I think that the
temps were higher than I'd like on the highway for the same reason.
Mark
