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Author Topic: High Altitude Suggestions  (Read 2580 times)

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Offline Gunslinger

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High Altitude Suggestions
« on: June 22, 2014, 11:38:03 AM »
Guys,
Planning on doing the Northern Colorado run next month, I live in Minnesota so the highest altitude my jeep has seen is about 1100 feet.  Wondering if anyone has any suggestions as to what preparation I should do to get ready for the high altitude.  I'd also ask for suggestions on special stuff to bring along in the " What if this happens" category.
Thanks
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Offline SteveW

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Re: High Altitude Suggestions
« Reply #1 on: June 22, 2014, 05:15:43 PM »
Coming from a flatlander it is not a problem for me but do remember some discussion of it. This may help or you may be o.k. for a short bit but long term it would be an issue

http://www.thecj2apage.com/forums/high-altitude_topic5354.html
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Offline athawk11

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Re: High Altitude Suggestions
« Reply #2 on: June 22, 2014, 09:20:33 PM »
Hi Gun,

I live at 5,500'.� I have gone to the last couple Fall Color Tours where we reach elevations as high as 13,000'.� I've not done anything special when preparing for those extreme elevations.� I am lucky enough to have a high altitude metering rod.� I'm not sure if it alone does anything to help my performance.

At the high elevation, I notice a small drop in power, but that's about it.� Fuel economy also drops a bit, as there is less air.

In prep, just have fresh fluids.� Go through all your nuts and bolts to make sure everything is tight.� The Rocky trails can shake things lose.� Double check your lugs.� � A member of our group lost a wheel last year.

I know you'll carry the basic tools and safety equipment, but you may also want to consider carrying some repair parts.�

Fuel line, wire, ignition parts, duct tape, extra oil and coolant, etc.�

I don't know if it was coincidence, but as a group, (two dozen willys) we lost three or four fuel pumps last year.� We also lost a radiator hose.� One willys also lost it's charging system.� There were other minor issues too, but I can't remember all of them.� Frankly, it was a rough year in terms of Willys failures.

Tim
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Offline Carls_jeep

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Re: High Altitude Suggestions
« Reply #3 on: June 22, 2014, 11:37:04 PM »
I have the standard metering rod and have been to a little over 11,000 feet with no problem. Two years ago I tried and it had vapor lock. After I replaced the fuel pump this past year it made it to the top just fine.

Offline scoutpilot

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Re: High Altitude Suggestions
« Reply #4 on: June 23, 2014, 05:19:35 AM »
Assuming you operate with a Carter WO, if you want to search for a High Altitude metering rod, its part number is 75-548. Unless you're lucky though, you will have a better chance of finding a NOS Capstan winch for $10.00. Shipped. ;)
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Offline athawk11

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Re: High Altitude Suggestions
« Reply #5 on: June 23, 2014, 03:01:04 PM »
Speak of the Devil...

ScoutPilot is the kind fellow that supplied me with the high altitude Meter Rod for my OD Willys.� I've heard through the grape vine that you're fresh out of these babies.

Tim
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Offline scoutpilot

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Re: High Altitude Suggestions
« Reply #6 on: June 23, 2014, 03:26:02 PM »
[size=12]Unfortunately yes. I've got three permanent searches going with no joy.[/size][/b]
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Offline Jesse

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Re: High Altitude Suggestions
« Reply #7 on: June 25, 2014, 02:16:08 PM »
How about multiple spark ignition? Such as an MSD unit. Should help boost your engine efficiency and burn more cleanly. It would also give you a second ignition as backup if you kept all of the stock pieces in place.

-Jesse
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Offline Carls_jeep

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Re: High Altitude Suggestions
« Reply #8 on: June 28, 2014, 02:07:32 PM »
You don't need the high altitude metering rod for anything up to 12,000 feet as far as I can tell. If you plan to take your Jeep to maybe 20,000 or 30,000 feet you will need more than a high alt. metering rod, you will need a super charger.

Offline Bruce_W

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Re: High Altitude Suggestions
« Reply #9 on: July 02, 2014, 05:57:40 PM »
  You don't need to change anything. Yes, you will feel a loss of power, but everyone there will. The air is less dense at higher altitude, and nothing short of Carl's supercharger will compensate for that. Just make sure that every part of the fuel delivery system is in good shape. It seems that small problems that are no problem, even not apparent, will become real problems at high altitude. Vapor lock seems to rear its ugly head more often than at lower elevations. I think it's because the boiling point of a liquid is lower at higher altitude (do I have that right?), and then we are working the engines pretty hard and building heat.
  As Tim said, it seems we had a lot of break-downs last year at FCT, but keep in mind that we had in line 15 jeeps on most rides, and counting those that left early or came late, I think the total was over twenty. I think we did pretty well, but there's room for improvement.
  On a side note, it seems to me that the jeep model that has had the most high-altitude fuel delivery problems on our Colorado runs, is GPW's. Something in their different (from CJ) fuel system? I can't say that MB's do or don't have the same problem, because we've never had an MB on one of our runs.
BW
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Offline Carls_jeep

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Re: High Altitude Suggestions
« Reply #10 on: July 03, 2014, 10:28:46 PM »
I had a lot of vapor lock issues at altitude until I insulated the fuel line from the pump to the carb.

Offline Bruce_W

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Re: High Altitude Suggestions
« Reply #11 on: July 04, 2014, 01:47:46 PM »
Yep, that line is right out there in the path of the hot air coming off the radiator. At least the fuel pump kind of hides behind the mount plate. I would think that a glass-bowl sediment bowl at the carb inlet might just make matters worse.

Another aside: in the '70s when we were fighting vapor lock in Chevrolets, big-block Suburbans were about the worst. We would build a new steel line to run from the fuel pump to the carb, running alongside the A/C low pressure hose, which runs cold, and tape them together with insulated tape.� �There was a kit for Camaros that included a small electric fan and ductwork to take cool air from in front of the radiator support and blow it on the front of the carburetor. BW
Until We Jeep Again...........