Home » Public Forums » GMCnet » [GMCnet] Vent holes
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| Re: [GMCnet] Vent holes [message #93689 is a reply to message #93684] |
Wed, 28 July 2010 17:14   |
Larry C
Messages: 1168
Registered: July 2004
Location: NE Illinois by the Illino...
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My understanding of the side vents, which I have not done since I am not a believer in them, was to get the engine compartment ventilated.... If you are concerned about the Carborator, it is sitting above the heat of the engine exhaust, I do not believe venting of any kind will help that.
You have to cool the source, the tanks, maybe cover them to keep the heat away then insulate the fuel lines, especially when near the exhaust. If the fuel is cool when it reaches the carb, it will in turn keep the fuel in the bowl cooler..... it sort of starts from storage and works its way to the engine.
LarC ( Thats my view, and I am sticking with it )
Gatsbys' CRUISER  08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" />
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| Re: [GMCnet] Vent holes [message #93697 is a reply to message #93689] |
Wed, 28 July 2010 18:34 |
emerystora
Messages: 4442
Registered: January 2004
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On Jul 28, 2010, at 4:14 PM, Larry wrote:
>
>
> My understanding of the side vents, which I have not done since I am not a believer in them, was to get the engine compartment ventilated.... If you are concerned about the Carborator, it is sitting above the heat of the engine exhaust, I do not believe venting of any kind will help that.
Not necessarily. Check out this site: http://www.gmcmhphotos.com/photos/showgallery.php?cat=3093
The air scoops under the bumper mounted at the sides of the radiator support bring cool air up through 4" aluminum dryer duct pipes to the upper rear corners of the motor box. This forces the hot air downward and out through the louvers mounted in the wheel well liners.
The top of the engine is now much, much cooler.
Emery Stora
77 Kingsley
Santa Fe, NM
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| Re: [GMCnet] Vent holes [message #93748 is a reply to message #93684] |
Thu, 29 July 2010 00:35 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
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| Steve Phillips wrote on Wed, 28 July 2010 16:15 |
Hi All
I am still trying to slow down the vapor lock . Would it help
drilling holes in the inter fenders? .Has anyone tried this for
cooling??????/
Help Appreciated
Steve
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I removed my fender liners after my engine fire a few years back. It was impossible to get to the top of the engine to put the fire out with them in place. I was going to drill holes in them to be able to insert a fire extinguisher nozzle but never got around to it.
The coach runs fine without fender liners.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] Vent holes [message #93749 is a reply to message #93697] |
Thu, 29 July 2010 00:43 |
Larry C
Messages: 1168
Registered: July 2004
Location: NE Illinois by the Illino...
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The top of the engine is now much, much cooler.
_______________________________________________________
Just a comment...
The air duct is moving the air to the engine top, the air flow causes a positive pressure and pushes the warm air down the sides and behind the engine. The radiator fan is doing its job of roaring and sending hot air all around the engine. I have been considering adding the ducts also to cool things down up there.
I just don't see those small vents having much impact, even if you cut the wheel wells, the air vents down the wheel wells and out the bottom.... I then wonder about the heat affecting the tire life.... seems any mod we make has a reaction somewhere.
LarC ( Of course I am looking at MY fender skirts, which A PO had cut up so I really dont know what they are supposed to look like new. )
Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" />
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| Re: [GMCnet] Vent holes [message #93752 is a reply to message #93735] |
Thu, 29 July 2010 00:49 |
Larry C
Messages: 1168
Registered: July 2004
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Spray the bottom of the fuel tanks with undercoating
_________________________________________
You talking like vehicle undercoating?? is it white??
I know this is and will be a real problem in the future and an easy " STANDARD " fix would be the cats meow.......
I personally feel the tanks are the primary source of the heating problem, they are not insulated. The fuel hose is secondary and the hot engine is third.... cure that, and other than the Ethanol additive, the problem should be nil.....
LarC ( Just thinking aloud )
Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" />
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| Re: [GMCnet] Vent holes [message #93790 is a reply to message #93768] |
Thu, 29 July 2010 10:00 |
Richard Denney
Messages: 920
Registered: April 2010
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On Thu, Jul 29, 2010 at 8:48 AM, Ken Coit <ktcoit@gmail.com> wrote:
> I repeat that my vapor lock symptoms occurred in February in the mountains
> of West Virginia. There was no radiant heat from the roadway, just cooling.
> A few minutes at the toll both took us down once the heat soak got to the
> carburetor. The float bowl was bone dry when I tried to use the accelerator
> pump manually. They say is was a plugged filter, but I think that not
> likely
> as it ran fine at speed.
>
Yes, it is true that the whole vapor lock discussion includes a lot of
anecdotal evidence unsupported by systematic measurements, and with
solutions that worked to solve one undefined problem being prescribed for
all possible problems. This is why the subject keeps going in circles.
Here is what I know:
1. Air does not flow through the engine compartment easily. I know this,
because my cooling system doesn't cool the engine with ram air, and requires
occasional fan activation. The fan is highly effective. The fan can only
serve to solve one of two problems: high pressure (resulting from the
blockage caused by the idle fan) in the shroud, or high pressure in the
engine compartment behind the fan. The latter might contribute to the vapor
lock problem. One owner has side vents with a bilge blower, and everyone
with side vents notes the waves of heat coming through them. That is heat no
longer trapped in the engine compartment. That does not mean side vents are
the only solution.
2. Fuel filters and electric pumps are often recommended as solutions. I
have clean filters placed in appropriate places (which does not include the
input to the carb), and an electric pump back by the tanks. But I still have
vapor lock after a high-temperature run followed by a idling stop. My fuel
system is not deficient.
3. Leaks in the fuel lines are often blamed. I'm quite sure I don't have
leaks upstream from the pump. Those lines have been replaced within the last
several years, with no effect on the problem.
4. Lack of insulation on the fuel line leading to the carb is often blamed,
but then there are people who never have vapor lock symptoms but who just
have a bare steel tube in that location. Bare steel isn't much of an
insulator.
5. Exhaust heating of the tanks is often blamed. Could be, but there are
many who don't have the problem and who have the factory exhaust
arrangement.
6. The recommendation to use non-oxygenated fuels is of no value to me. I
would have to drive farther than the range of the coach to find any.
Clearly, to me, air flow in the engine compartment is a problem. Thus,
anything that improves air flow through the engine compartment will probably
contribute to the solution. I suspect there is a pressure bubble on the top
of the engine that air flows around even when air flows. Here are some
strategies aimed at that issue:
1. A cold-air tube from the snorkel of the air cleaner to the cool air in
front of the radiator.
2. Side vents. Bilge blowers?
3. Cold-air (with dynamic pressure while moving) ducting to hot spots. I
worry that some of these strategies block other air flows, but not
everything is troubled by being hot. The targets for cool are the ignition
module and the fuel system.
4. Fender well vents. I favor a 3 or 4" hole in the fender well in any case
to provide a access to the engine area with a fire extinguisher.
5. Air dam, to provide a vacuum under the engine compartment to draw air
through.
Carb heat results from poor air flow, but also from the manifold. Blocking
the crossover is a key step, it seems to me. But it is not curative--my
crossover is blocked and I still have issues.
Some report that fuel is boiling in the tanks, but that has never been true
for me even right after having a vapor lock issue. A big sigh from the tank
upon opening the cap is all I ever see. At 1 psi (controlled by ventilation
system or cap vent), the top and bottom surfaces of the tank will have a
total of 15 pounds of force, or so. I can deflect the bottom of the tank
noticeable by pressing the middle of it by that amount, and that deflection
displaces air. That sigh is the air being released.
Insulation doesn't prevent heat, it just slows it down. For it to work,
there has to be a source of coolness, or the heat will eventually soak
through the insulation. Insulation strategies need to consider that fact.
For radiant heat, a sheet metal shield with ventilation behind it will work
well, but that won't work at all for convective heat, which would keep that
ventilation hot. We are just guessing at the heat sources most of the time.
Those of us who experience the problem even when ambient conditions are not
that hot probably should confirm our ignition timing, which can cause an
engine to run hot if not correct.
In the end, it will probably be a combination of things, including making
sure everything in the engine compartment is tip-top, to solve the problem.
When there is more than one potential solution, there will be some that have
a big effect and some that work at the margins. And there will be some that
are expensive and some that are cheap. Do the cheap things that have the
biggest effect first. I'm thinking holes in the inner fender, ducting around
the front of the radiator, cool-air ducting to the air cleaner snorkel,
insulating the fuel hose, flapper vents in the fan shroud, and making sure
the fuel delivery system is in perfect condition. If that doesn't work, I'll
work on better heat shielding of the fuel pump area back by the tanks. If
that doesn't work, I'll try side vents. Then, bilge blowers on those vents.
Then more ducting to the engine compartment, but before that I'm going to
start sensing temperatures more carefully. Insulating the tanks seems a
low-percentage move, and difficult at best, so I'm saving that for last.
Rick "trying to think systematically" Denney
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| Re: [GMCnet] Vent holes [message #93795 is a reply to message #93790] |
Thu, 29 July 2010 10:28 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
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""Yes, it is true that the whole vapor lock discussion includes a lot of
anecdotal evidence unsupported by systematic measurements, and with
solutions that worked to solve one undefined problem being prescribed for
all possible problems. This is why the subject keeps going in circles.""
Rick I certainly don't disagree with your thoughts. This discussion is similar to the never ending brake discussions. Some people have no issues, others have significant issues. I know our coaches will vary in almost all respects, but as a production vehicle I doubt the orignal configuration varies from acceptable to poor in any one area. What I think we have are several problems going on at the same time on some of these coaches. That's why some people's solutions seem to work for some and not for others. I've been lucky to get a coach that is almost original in all respects. My brakes are fine and once I discovered my fuel problem, I have no vapor lock even at 110F and no electric pump running (even though I have one due to a previously mis-understood issue). I think I'm just lucky and sympathise with those that have problems with whatever configuration they have. It looks like we have a whole menu of options for people to consider. I also suspect that "vapor lock" is a general term being used for conditions that may not actually be vapor lock.
Bob de Kruyff
78 Eleganza
Chandler, AZ
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| Re: [GMCnet] Vent holes [message #93804 is a reply to message #93790] |
Thu, 29 July 2010 10:56 |
Charles
Messages: 455
Registered: January 2004
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Rick,
Something I think you might have overlooked.
I asked here on the gmclist about where does the vapor lock
occur, before or after the fuel pump. All replies were between
the fuel pump and fuel tank. If this is indeed a fact and you
move the fuel pump back by the fuel tank you have eliminated
any problems with air flow in and around the engine as a contributor
to the vapor lock problem. Let's first determine where the vapor
lock occurs and then address the problem. With Ken Henderson's
help, I have gone to two electric fuel pumps back by the fuel tanks.
Each with its own separate tank and switch. I have completely
eliminated the fuel selector valve. If the vapor lock does occur
between the pump and the tank I should be able to switch tanks
and keep going. I'm looking forward to a long trip in hot Texas
sun so I can find out if this works. On a recent 100 mile trip
to a Classics rally in 95 degree temperatures I did not encounter
any problems. Coming home in 85 degree temperatures, same
story, no problems. Started with full tank returned with a little over
3/4 down to 1/2 tank of fuel. Wish now fuel tank had been lower
so I could have had more chance for heat problems in the tanks.
I have had vapor lock and boiling fuel problems for years. I have
pictures where fuel boiled out of my fill tube and ran down the side
of my coach in Oct. 2005. While adding the second electric
fuel pump I found both vent lines had fuel in them. I suspected
this due to the problems I have been having when filling my tanks.
Is blocked vent lines a contributor? Have youconsidered that. I
didn't see it in your well presented post. I'm with you in a big way,
other than ethinal fuel, what/where is the real cause. I think, .
we need to start a reward fund for the guy that finds the solution.
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Charles Wersal
Duncanville, Texas
26 foot 1975 Glenbrook
Pandora's Box
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| Re: [GMCnet] Vent holes [message #93805 is a reply to message #93795] |
Thu, 29 July 2010 11:02 |
Larry C
Messages: 1168
Registered: July 2004
Location: NE Illinois by the Illino...
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It looks like we have a whole menu of options for people to consider. I also suspect that "vapor lock" is a general term being used for conditions that may not actually be vapor lock.
________________________________________
I agree with that thought. The production vehicle left in a standard configuration, the engineers had " debugged " the prototype and the production models were all carbon copies with on going upgrades.
It would be interesting to see what mods, like headers ( Hotter ), or the manifold mods or replaced with almunium, even the rerouted oversized exhaust pipes....to see what part the new piece or mod takes in the current "vapour lock" crisis...
Obviously, the ethanol has not helped the situation, then again if Bob and others have not had a problem, then maybe we are looking at the wrong crisis.
If the stock production GMCs are not seeing this problem, then we should take an increasingly close look at the mods that have been done and find a fix for that mod. All GMCs with that mod should copy that fix to get this under control.
My GMC is basically, STOCK, little if any mods and to this point ( KNOCK ON WOOD ) has not had the Vapour Lock issue so that puts me in Bob D's corner....
Perhaps we should start a data base, listing GMCs, mods and if the vapour lock issue has been an issue.
Just my thoughts
LarC ( Thinking this issue may need to be confronted at some time so notime like the present to collect data )
Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" />
http://www.gmceast.com/travel
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[Updated on: Thu, 29 July 2010 11:08] Report message to a moderator |
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| Re: [GMCnet] Vent holes [message #93812 is a reply to message #93684] |
Thu, 29 July 2010 11:13 |
James Moore
Messages: 71
Registered: January 2004
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Rick,
Since I have never experienced so called vapor lock, I can't recommend a solution but think there is probably a simple solution that is being over looked. I understand that when GM was developing the motor homes, they spent time on the AZ test track in hot weather. If they had seen a problem with hot weather operation, I think they would have addressed it. I know everyone is going to say but the gas was different then and the gas is the problem. If that is the case, I should have big time vapor lock because I always buy the cheapest gas available and never try to avoid 10% ethanol. The only effect I have seen caused by ethanol is a drop in fuel economy. I also run the Onan to power the roof air while traveling in hot weather and haven't had any problems with it stopping.
Things I think should be addressed are:
1. Is the ignition advance setup correctly and working correctly. On my recent 2985 mile cross country trip, I experienced loss of power and engine stumble and increased coolant temps. I found the centrifugal advance was stuck and the engine ran fine after I broke it loose. After that, everytime the engine started running bad, I downshifted and reved it to over 3000 rpm and the problem cleared away. Next job is to remove the distributor and lube the centrifugal advance. Just haven't figured out what kind of grease GM calls distributor grease.
2. Is the float valve in the vent line working correctly. If it is working correctly, there should be no pressure build up in the gas tanks. All the pressure should be vented through the carbon canister. If the valve is not working correctly, it can cause pressure build up in the gas tanks and can also cause fuel starvation when air cannot get into the tanks to replace the fuel that has been used. If there is a vacuum in the fuel tanks, electric pumps won't work any better than mechanical pumps. If I ever develop vapor lock, one of the first things I will do is remove the vent float valve. The only reason I haven't removed it is to prevent gas running out of the vent canister when I fill up.
3. Heat buildup in the carb. It is normal for gas to percolate out of a carb when the engine is shut down after a hot run. This can cause two problems. The liquid gas in the manifold can flood the engine making it hard to start after a short shut down. It can cause fuel starvation after an extended shut down. On hot starts after short shut downs, I depress the gas pedal until it is over 50% open and then crank the engine. When the engine fires, I rev it to 2500+ rpm for a few seconds until it stabilizes and then let it idle. I installed a heat dissipation gasket years ago. I don't know if it works but it can't hurt. I know you have an aluminum manifold with not exhaust heat. I have a similar setup on my blazer with a SBC and the gas will percolate out of the carb on hot shutdowns.
4. Is all possible emission equipment removed? WA does not require smog checks on vehicles over 25 yrs old. As a result, I have removed all smog equipment and set up the engine similar to how a presmog engine would have been setup. The initial timing is 12 BTC. The vacuum advance is connected directly to the intake manifold. The vent canister is disconnected from the intake manifold. The only vacuum connections are brake booster, vacuum advance, and heating system. All unused vacuum connections are plugged. The distributor is setup as per the writeup on the western states website. I don't know if this helps vapor lock, but it sure improves driveability. On a cold start, the engine does not die several times and it seems to fire quicker on hot starts. It idles smoothly at 650 rpm in drive and does not diesel when the engine is switched off. If I ever plug the manifold, the choke will be connected to a 1/4 " copper line wrapped around the exhaust manifold or an ele
ctric choke installed. I had too many cold start problems with the aluminum manifold on the blazer before I installed an electric choke.
5. I removed the carb filter and only have the tank sock filters. I have had too much trouble with carb filters on other vehicles and have routinely removed them since about 1978 with no adverse effects. I inspect gas lines and replace any that are cracked. I also replaced the carb float and installed a rebuild kit shortly after getting my GMC. What people are calling vapor lock may be flooding instead of fuel starvation. The foam floats in Quadrajets will soak up gasoline and sink causing flooding. I always replace the carb float when I rebuild a Quadrajet.
If I ever encounter vapor lock, I will install a fuel pressure gauge (It will be outside and not piped inside the GMC for safety reasons) to see if I am losing fuel pressure and have fuel starvation. If I am not losing fuel pressure, vapor lock may actually be flooding. I would drive the GMC and have someone following me to observe the exhaust color. Black smoke, flooding.
Not sure this will help, but maybe it will give you some ideas of things to look at before you start all the modifications you mentioned.
Jim Moore
75 PB with no vapor lock
Parked in Pinehurst, GA where is going to be over 95F today.
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| Re: [GMCnet] Vent holes [message #93817 is a reply to message #93804] |
Thu, 29 July 2010 11:29 |
emerystora
Messages: 4442
Registered: January 2004
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On Jul 29, 2010, at 9:56 AM, Charles wrote:
> Rick,
> Something I think you might have overlooked.
> I asked here on the gmclist about where does the vapor lock
> occur, before or after the fuel pump. All replies were between
> the fuel pump and fuel tank.
How do they know?
I cannot agree with that. A fuel pump creates a partial vacuum on the inlet side and creates pressure on the outlet side. So there will be lower pressure on the line coming from the tank to the fuel pump. If the fuel is going to vaporize it will do so in the lowest pressure area. So it can occur prior to the fuel pump.
Of course, it will also vaporize in the hottest section as well. So that can be anywhere between the fuel pump and the carb or throttle body.
Another thing that most people posting about vapor lock overlook is that it usually occurs at higher elevations. This is due to the lower air pressure which allows fuel to boil at a lower temperature. Living at 7200 feet elevation I used to have frequent problems with vapor lock even prior to the high levels of ethanol in the fuel.
Keeping the lines as short as possible between the fuel tank and the pump should be one goal and the other is to keep the lines in the coolest possible positions.
I have not had vapor lock problems since I installed the vents in my wheel wells, installed ducts for cool air to my engine box, and moved my lines to the outside of the frame (together with my electric fuel pump, selector valve and filter) but I have had problems priming the fuel pump when I run out of fuel in one tank and switch to the other.
I am in the process of putting two electric fuel pumps right into my tanks which will eliminate the inlet lines for the pump and also eliminate the fuel selector valve. It will also involve installing 3/8" steel lines in place of the rubber hoses so it will not be necessary to drop the tanks in the future to replace rubber lines.
I will report back on it when it is completed. I will also be giving a seminar on it at the GMCMI convention in DuQuoin, IL.
One can see how I mounted the parts outside the frame at http://www.gmcmhphotos.com/photos/showgallery.php?cat=4969
The link for the louvers in the wheel wells and the vent hoses to the engine compartment are here: http://www.gmcmhphotos.com/photos/showgallery.php?cat=3093
This doesn't show how I ran the steel line up and to the back of my engine. I will put up some photos of that later.
I ren the 3/8" steel brake line along the outside of the frame and then up right behind the brake combination valve to the rear top of the engine. I then have a short flexible piece of stainless steel braided teflon hose connecting to the throttle body. If you have a carb then it would be necessary to run the line across the engine area and to the front of the carb.
After changing the components to the outside of the rails it seemed to have totally eliminated my vapor lock problems. I haven't had any for the last 4 or 5 years and we have been across the country almost every year at elevations ranging from below sea level (Death Valley) to almost 10,000 feet.
Emery Stora
77 Kingsley
Santa Fe, NM
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| Re: [GMCnet] Vent holes [message #93824 is a reply to message #93812] |
Thu, 29 July 2010 12:04 |
Richard Denney
Messages: 920
Registered: April 2010
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On Thu, Jul 29, 2010 at 12:13 PM, Jim Moore <j.moore.jr@mindspring.com>wrote:
> 1. Is the ignition advance setup correctly and working correctly.
>
Yup, good thing to check. I checked mine, and it's all correct. I routinely
check my centrifugal advance weights, but I have never experienced the
normal symptoms of the weights being stuck.
2. Is the float valve in the vent line working correctly.
Yup. Checked that, too. Working fine. My ventilation system works as it
should. I have Cinnabar tanks, which provide a tray for the lines, so they
are not pinched. I installed right-angle fittings where the hoses turned to
go up the fender well to prevent pinching there. I have never actually
experienced blow-back in my tanks.
3. Heat buildup in the carb.
>
Yes to that, too. I don't worry about percolation after shut-down. With my
electric pump, I've never had a problem starting the engine, hot or cold,
except when I was having symptoms. Most recent scenario: Stopped and talking
on the radio in a parking lot. Ambient temps were around 90. I had just been
driving about 15 minutes in town traffic, after a highway run of 100 miles
or so. Engine temps were nominal. 20 gallons of fuel in the tanks. After
several minutes of idling, the engine just stopped. It could not be
restarted. I went in and shopped for groceries for half an hour, and came
back out. Engine started right up and ran fine after that. I thought I'd run
out of gas, even though I knew I had to have at least 20 gallons in the
tanks. 600 feet above sea level.
I also, as you say, installed an aluminum radiator with no crossover, and
also headers, which may add to the problem. A rear muffler instead of the
front mufflers might help, too, but that's not easy on my 230. All that good
engine-cooling stuff, though, just makes the compartment hotter, because
that is where the heat is dumped.
> 4. Is all possible emission equipment removed?
Yup. Wasn't that much to begin with on my '73. I'm still running crankcase
ventilation, of course. I'm getting vacuum advance from the manifold (some
will say that's a cure, and others will say it's the disease), just as you
say. 10 degrees BTDC for me--heard a bit of pinging at 12. There are no
vacuum leaks--all the hoses are recently replaced with very expensive
silicone that I really hope the local rodents do not eat. The engine reads
18 inches of mercury at 600 RPM idle, no AC and in Park. 16 with AC and
Park.
> 5. I removed the carb filter and only have the tank sock filters.
I have inline filters (large ones) between the tanks and the selector valve,
and the valve feeds straight into the pump. I have another very free-flowing
sintered bronze performance filter in front of the carb, but not filter in
the carb. I'm more afraid of dirt keeping the float valve from closing than
vapor lock. Carb was rebuilt within last 10K miles by Dick Paterson. Oh, and
I replaced the Carter fuel pump a couple of years ago, with no change.
> If I ever encounter vapor lock, I will install a fuel pressure gauge (It
> will be outside and not piped inside the GMC for safety reasons) to see if I
> am losing fuel pressure and have fuel starvation. If I am not losing fuel
> pressure, vapor lock may actually be flooding. I would drive the GMC and
> have someone following me to observe the exhaust color. Black smoke,
> flooding.
>
Yes, and this reinforces Bob's point, with which I fully agree, that vapor
lock is being blamed for a range of apparent fuel starvation issues.
Installing a pressure gauge is not something I want to do. If my easy fixes
don't solve the problem, though, I will. I will certainly do it before the
difficult fixes. Cool air to the carb--that's a no-brainer. It's good for a
number of reasons. Ducting around the front of the radiator--GMC made that
change themselves in later years. Fire-sleeve on the fuel line at the carb?
No-brainer, and a good safety measure in case of an engine fire. I have this
feeling that when I solve the problem of needing the engine fan to run from
time to time to keep the engine cool on highway cruise, I may also solve the
hot fuel problem, assuming it's a hot fuel problem.
But while it's possible the problem is upstream from the pump, my gut just
rebels at the thought.
I have to set this issue aside, however. We had a saggy roof with 30 inches
of snow on it, and we found a rafter (2x12 Douglas fir 18 feet long on an
8/12 pitch) that was cracked halfway through. Work to be done there. Two
trees fell over, just missing the house, in last weekend's storm. Work to be
done there. The Redhead wants new cabinets in the loft office while the
furniture is moved out (to repair the rafter). Work to be done there. And my
dadgum boss keeps expecting me to work!
Rick "who can do the easy stuff in an afternoon, which ought to be available
come November" Denney
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