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Still having issues in Colorado [message #313485] Sun, 19 February 2017 19:52 Go to next message
thorndike is currently offline  thorndike   United States
Messages: 406
Registered: January 2011
Location: Conifer, Colorado
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Senior Member
Since we purchased a fixer-upper home in Conifer, Co., it has been quite a while since I was able to get back to working on my GMC. When I last posted I had just driven my GMC across the country and lost power just as I was passing Denver on the highway. The loss of power was such that I was only able to reach a top speed of about 13 miles an hour for the last 20 miles of the drive. Most of the suggestions I was given revolved around the fuel filter as the loss of power was not gradual. The consensus was that the filter may have collapsed.

After much delay I was finally able to get the filter out and was dismayed to see that it looked perfect. I put the new filter in along with a new battery and fired the GMC up. It ran rough for a bit as it had been sitting for way too long but soon began to smooth out. I had high hopes when I backed out of the parking spot. Unfortunately, those hopes vanished immediately as I found that I still had no power. The GMC was barely able to make it back up the slight incline to get back to parking spot despite having the pedal to the floor.

I am going to reach out to the local club as well, but was hoping to get as much input as possible toward possible/likely solutions.

Robert


Robert Peesel 1976 Royale 26' Side Dry Bath Conifer, Colorado
Re: Still having issues in Colorado [message #313486 is a reply to message #313485] Sun, 19 February 2017 20:00 Go to previous messageGo to next message
Hal StClair   United States
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
Senior Member
I think I'd look for a second filter somewhere.
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: Still having issues in Colorado [message #313488 is a reply to message #313486] Sun, 19 February 2017 20:08 Go to previous messageGo to next message
thorndike is currently offline  thorndike   United States
Messages: 406
Registered: January 2011
Location: Conifer, Colorado
Karma: 0
Senior Member
Hal,

That's a good point. I will crawl under to see if another inline filter had been installed in the past.

Thanks for the idea!


Robert Peesel 1976 Royale 26' Side Dry Bath Conifer, Colorado
Re: Still having issues in Colorado [message #313491 is a reply to message #313488] Sun, 19 February 2017 20:33 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
Messages: 2126
Registered: July 2004
Location: Minden nevada
Karma: 6
Senior Member
If it's not a filter problem could be the mechical fuel pump is defective . Try substituting an electric pump if in doubt. Are you sure the ignition components are ok? Pull the plugs and do a compression check. If the motor has a lot of miles on it the timing chain may have skipped a tooth?

Roy Keen Minden,NV 76 X Glenbrook
Re: [GMCnet] Still having issues in Colorado [message #313492 is a reply to message #313485] Sun, 19 February 2017 20:36 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
Messages: 959
Registered: January 2011
Karma: 4
Senior Member
It certainly does sound like fuel starvation. It could also be a clogged air filter or even a collapsed muffler baffle blocking the exhaust.

I also would try replacing the distributor module as that could give symptoms as you describe and is an easy thing to change out before doing other things.

Emery Stora
77 Kingsley
Frederick, CO

> On Feb 19, 2017, at 6:52 PM, Robert Peesel wrote:
>
> Since we purchased a fixer-upper home in Conifer, Co., it has been quite a while since I was able to get back to working on my GMC. When I last
> posted I had just driven my GMC across the country and lost power just as I was passing Denver on the highway. The loss of power was such that I was
> only able to reach a top speed of about 13 miles an hour for the last 20 miles of the drive. Most of the suggestions I was given revolved around the
> fuel filter as the loss of power was not gradual. The consensus was that the filter may have collapsed.
>
> After much delay I was finally able to get the filter out and was dismayed to see that it looked perfect. I put the new filter in along with a new
> battery and fired the GMC up. It ran rough for a bit as it had been sitting for way too long but soon began to smooth out. I had high hopes when I
> backed out of the parking spot. Unfortunately, those hopes vanished immediately as I found that I still had no power. The GMC was barely able to
> make it back up the slight incline to get back to parking spot despite having the pedal to the floor.
>
> I am going to reach out to the local club as well, but was hoping to get as much input as possible toward possible/likely solutions.
>
> Robert
> --
> Robert Peesel
>
> 1976 Royale 26'
>
> Side Dry Bath
>
> Morrison, Colorado
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Still having issues in Colorado [message #313495 is a reply to message #313492] Sun, 19 February 2017 20:58 Go to previous messageGo to next message
thorndike is currently offline  thorndike   United States
Messages: 406
Registered: January 2011
Location: Conifer, Colorado
Karma: 0
Senior Member
Emory,

Thanks for the response. I didn't think about the distributor module as I had to replace it on my way across the country. I had to replace the module when it gave out on me in the middle of Missouri. The message string is here: http://gmc.mybirdfeeder.net/GMCforum/index.php?t=msg&goto=289253&rid=2027#msg_289253

I will be looking for an extra filter that might exist and will replace the module again. Those are both easy fixes.

Robert


Robert Peesel 1976 Royale 26' Side Dry Bath Conifer, Colorado
Re: [GMCnet] Still having issues in Colorado [message #313499 is a reply to message #313495] Sun, 19 February 2017 21:26 Go to previous messageGo to next message
Hal StClair   United States
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
Senior Member
If you have a pressure gauge you might just pull the line off the carb and check for fuel/pressure there also. It should tell you if it's a fueling problem of not.
Hal


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM
Re: [GMCnet] Still having issues in Colorado [message #313500 is a reply to message #313499] Sun, 19 February 2017 21:31 Go to previous messageGo to next message
thorndike is currently offline  thorndike   United States
Messages: 406
Registered: January 2011
Location: Conifer, Colorado
Karma: 0
Senior Member
Hal,

That is an interesting idea. What kind of pressure gauge would be used?

Bob


Robert Peesel 1976 Royale 26' Side Dry Bath Conifer, Colorado
Re: Still having issues in Colorado [message #313505 is a reply to message #313485] Sun, 19 February 2017 22:16 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
Messages: 4508
Registered: April 2011
Karma: 39
Senior Member
thorndike wrote on Sun, 19 February 2017 19:52
Since we purchased a fixer-upper home in Conifer, Co., it has been quite a while since I was able to get back to working on my GMC. When I last posted I had just driven my GMC across the country and lost power just as I was passing Denver on the highway. The loss of power was such that I was only able to reach a top speed of about 13 miles an hour for the last 20 miles of the drive. Most of the suggestions I was given revolved around the fuel filter as the loss of power was not gradual. The consensus was that the filter may have collapsed.

After much delay I was finally able to get the filter out and was dismayed to see that it looked perfect. I put the new filter in along with a new battery and fired the GMC up. It ran rough for a bit as it had been sitting for way too long but soon began to smooth out. I had high hopes when I backed out of the parking spot. Unfortunately, those hopes vanished immediately as I found that I still had no power. The GMC was barely able to make it back up the slight incline to get back to parking spot despite having the pedal to the floor.

I am going to reach out to the local club as well, but was hoping to get as much input as possible toward possible/likely solutions.

Robert
I have said this before, but maybe not to you specifically: Get a mostly full 5 gallon gas can and run a hose from it through an electric fuel pump to the input of the mechanical fuel pump on the front of the engine. Power the fuel pump from the cigarette lighter.

If it runs right that way, start your troubleshooting working your way back from the carb to the tanks.

I am still not convinced that you don't have a tank full of crap gas.
Re: [GMCnet] Still having issues in Colorado [message #313507 is a reply to message #313485] Sun, 19 February 2017 23:04 Go to previous messageGo to next message
Richard Denney is currently offline  Richard Denney   United States
Messages: 920
Registered: April 2010
Karma: 9
Senior Member
I missed the earlier discussion, but did someone previously mention the
filter socks in the tanks? Mine were clogged when I bought my coach.

Rick "who got it to work temporarily by applying just a bit of compressed
air back through the fuel hose to push the clogged sock off the pickup
tube" Denney


On Sun, Feb 19, 2017 at 8:53 PM Robert Peesel wrote:

> Since we purchased a fixer-upper home in Conifer, Co., it has been quite a
> while since I was able to get back to working on my GMC. When I last
>
> posted I had just driven my GMC across the country and lost power just as
> I was passing Denver on the highway. The loss of power was such that I was
>
> only able to reach a top speed of about 13 miles an hour for the last 20
> miles of the drive. Most of the suggestions I was given revolved around the
>
> fuel filter as the loss of power was not gradual. The consensus was that
> the filter may have collapsed.
>
>
>
> After much delay I was finally able to get the filter out and was dismayed
> to see that it looked perfect. I put the new filter in along with a new
>
> battery and fired the GMC up. It ran rough for a bit as it had been
> sitting for way too long but soon began to smooth out. I had high hopes
> when I
>
> backed out of the parking spot. Unfortunately, those hopes vanished
> immediately as I found that I still had no power. The GMC was barely able
> to
>
> make it back up the slight incline to get back to parking spot despite
> having the pedal to the floor.
>
>
>
> I am going to reach out to the local club as well, but was hoping to get
> as much input as possible toward possible/likely solutions.
>
>
>
> Robert
>
> --
>
> Robert Peesel
>
>
>
> 1976 Royale 26'
>
>
>
> Side Dry Bath
>
>
>
> Morrison, Colorado
>
>
>
> _______________________________________________
>
> GMCnet mailing list
>
> Unsubscribe or Change List Options:
>
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
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Re: [GMCnet] Still having issues in Colorado [message #313509 is a reply to message #313500] Mon, 20 February 2017 00:00 Go to previous messageGo to next message
Hal StClair   United States
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
Senior Member
I'd just use something like this:
http://www.ebay.com/itm/Fuel-Pump-And-Vacuum-Tester-Automotive-Pressure-Test-Diagnostic-Tool-Gauge-/331263953881?hash=item4d20decbd9:g:yI8AAOSwymxVQmQ L&item=3312639
HF may have something that would work too.
Hal
Here's one;
http://www.harborfreight.com/catalogsearch/result?q=vacuum+test


"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane." 1977 Royale 101348, 1977 Royale 101586, Diesel powered, 1974 Eagle Bus 45',w/slideout, Rio Rancho, NM

[Updated on: Mon, 20 February 2017 00:03]

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Re: [GMCnet] Still having issues in Colorado [message #313514 is a reply to message #313509] Mon, 20 February 2017 05:46 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
Senior Member
If not a second fuel filter somewhere along the frame, you also may have an internally collapsed fuel line. Might try to clear the fuel line with compressed air. Consider using the fuel can idea to get her home, where it might be easier to fix.
Tom, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: Still having issues in Colorado [message #313524 is a reply to message #313485] Mon, 20 February 2017 08:54 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
You should be able to easilly tell if fuel. When it looses power use max throttle to totally depleat the fuel in the carb and turn off the exactly when you release the pedal to get a " clean" shutoff. Now open the hatch and remove the air cleaner. While shinning a flashlight down the primaries of the Qjet watch for 2 distinct continuous fuel streams one in each barrrel like a good squirt gun would deliver as you manually operate the throttle linkage. If the bowl is full you should get about 5 full pumps til the carb bowl ( squirt gun tank) is empty. I suspect you will only get some dribble and confirm a fuel problem. If you do get pleny of good duel fuel squirts, (unlikely) put the air cleaner back on and hold the accelerator all the way firmly to the floor while you crank to clear the flooded condition you just created. You should now know if you have a fuel issue or one of the other issues others have listed above. Everyone always says "fuel filter" in these situations but in my experience that is rarely the case. If the system was previously clean it doesn't suddenly get dirty. You could have porosity in the rubber fuel lines. In fact if they have not been replaced with barrier type mutiple wall lines they are most likely bad as the old type lines are not ethanol tollerant and fail in a few short years of exposure. Very dangerous.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Still having issues in Colorado [message #313578 is a reply to message #313524] Mon, 20 February 2017 20:41 Go to previous messageGo to next message
thorndike is currently offline  thorndike   United States
Messages: 406
Registered: January 2011
Location: Conifer, Colorado
Karma: 0
Senior Member
Thanks for the ideas John. I have already replaced the 'easily accessible' fuel lines which means, of course, that I have not replaced the lines above the fuel tanks.

I will try your test when I get back down to the coach.

Bob


Robert Peesel 1976 Royale 26' Side Dry Bath Conifer, Colorado
Re: [GMCnet] Still having issues in Colorado [message #313580 is a reply to message #313578] Mon, 20 February 2017 20:50 Go to previous message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Robert, don't know if this has already been covered, but, will mention it
anyway if it has not been covered. The electric tank switching valve has a
history of failure with alcohol "enhanced" fuels. Regardless of which tank
is selected, an insufficient amount of fuel flows. Solution for testing is
to plumb around it and see if the engine runs. You will need to block off
the tank you are not using.
Mine failed. The replacement one is resistant to alcohol fortified fuels.
Jim Hupy

On Feb 20, 2017 6:42 PM, "Robert Peesel" wrote:

> Thanks for the ideas John. I have already replaced the 'easily
> accessible' fuel lines which means, of course, that I have not replaced the
> lines
> above the fuel tanks.
>
> I will try your test when I get back down to the coach.
>
> Bob
> --
> Robert Peesel
>
> 1976 Royale 26'
>
> Side Dry Bath
>
> Conifer, Colorado
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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