starting the engine

kstockwell

kstockwell

Member
May 24, 2016
376
2
18
I'm over a year in, 2000 miles and feeling pretty good. I've got a grease gun, I've used it, I've checked all fluids (not the differential yet), and
changed the oil.

I still struggle with starting the rig. After it's been running and sits for even a handful of hours it starts up. If it's stilling longer, I'm
still not sure what to do.

What I've been doing
put the key to one click below start and hold the gas down, slowly count to 20
turn the key and let it crank.

What I think that does is 1 set the choke, 2 turn on the fuel pump to move fuel to the carb. Is the second part right?

How long do I let it crank before pausing and starting over? How long should it take? Outside people tell me it smells like gas (i'm flooding it),
but why can't I smell that inside, i'm right over the engine?

Is letting it crank 30 seconds OK?

When it does start it often stalls right off, I crank again and it starts again quickly and I give it gas and rev it to keep it from stalling.

Am I doing it wrong? On my list is change the small fuel filter in the carb, haven't done that yet. Could there be a problem or am I just doing it
wrong? I do notice more energetic starter motor noises if I hold in the batter link to the coach batteries but it doesn't make it start sooner

thanks
kelly

--
1978 Kingsley
Putney VT
 
Do you know if you have an electronic fuel pump?
--
1977 Palm Beach, 455, mostly stock and original
 
I am pretty sure I do, and the PO replaced it just before I got it.

He mentioned putting in a new fuel pump for me hoping it would stop any vapor lock issues. As far as I can tell I've not had that.

Is there an easy way for me to tell?
--
1978 Kingsley
Putney VT
 
Kelly,

If you have an electric fuel pump, you should be able to hear it come on when you turn the ignition key on (to the run position). If you can't hear
anything from the driver's seat, get out and walk around to the left (driver's) side of the coach, lean over and listen for a pulsating sound or a
motor whine.

It also sounds like your choke is either non existent, or not adjusted correctly. With fuel in the carburetor (why you turn the ignition on for a
short period to let the electric pump prime the carb.), you should be able to 'set' the choke by pressing the gas pedal to the floor once or twice,
then letting off the gas pedal completely. IF the choke is functioning properly, the engine should start up after cranking for a few seconds, or
running through a few strokes.

You can check this by opening your engine hatch, removing the air cleaner (or at least the top) so you can see the choke (the butterfly valve on the
primaries toward the front of the engine). If you don't feel comfortable adjusting the choke, just about any old school mechanic, who is used to
working on carbureted vehicles, can do it for you in a matter of minutes, IF all the linkages are in tact.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
Kelly, pretty sure that your choke is not set properly. You could turn the
key on and listen for an electric fuel pump to run. That would fill the
carburetor float bowl with fuel if an electric pump were present. If no
pump, it won't accomplish much, EXCEPT WHEN YOU HAVE AN ELECTRIC CHOKE PULL
OFF. If you have an electric choke pull off, and you turn the ignition on,
and the choke is wired so it comes on with the key, it will open the choke
prematurely.
Assuming that you DON'T HAVE an electric fuel pump, and that your
electric choke is wired from the alternator so that it does not open
prematurely, the starting process should go something like the following.
Insert key into ignition.
Press down slightly on the throttle ONE TIME ONLY. This will set the
choke.
With your foot off the throttle, turn the key to start. Engine should
crank over and start and run on fast idle without stalling. It should start
within 10 - 15 seconds of cranking.
IF NO START, something is not correct.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

> I am pretty sure I do, and the PO replaced it just before I got it.
>
> He mentioned putting in a new fuel pump for me hoping it would stop any
> vapor lock issues. As far as I can tell I've not had that.
>
> Is there an easy way for me to tell?
> --
> 1978 Kingsley
> Putney VT
>
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> Unsubscribe or Change List Options:
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>
 
Thanks all!

I wonder if my choke has changed, I swear last year when I read about pushing the pedal to the floor before starting (and not touching it while
cranking) it started perfectly for awhile.

I will check the choke (opening the hatch etc). Heading to San Diego for work tomorrow, but home over the weekend to check these things out. It does
start like a champ when warm.

Also, I'm not sure I hear a fuel pump go on. another thing I'll check on. And, i'll finally get to that fuel filter.

-kelly

--
1978 Kingsley
Putney VT
 
If the coach sitss for awhile, engine heat MAY cause fuel in the carb float bowl to evaporate. If that is the case here, I stab the accel pedal several time to force feed some fuel into the carb throat with the accelerator pump. THEN push pedal to floor SLOWLY to set the choke's fast idle setting and MAYBE this will solve your problem.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~~ k2gkk @ hotmail dot com ~~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ex-Palm Beach, 76 ~ ~ ~
~~ k2gkk + hotmail dot com ~~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
______________
*[ ]~~~[][ ][|\
*--OO--[]---O-*
________________________________________
From: Gmclist [gmclist-bounces] on behalf of kelly stockwell [snowsto]
Sent: Sunday, August 6, 2017 20:16
To: gmclist
Subject: Re: [GMCnet] starting the engine

Thanks all!

I wonder if my choke has changed, I swear last year when I read about pushing the pedal to the floor before starting (and not touching it while
cranking) it started perfectly for awhile.

I will check the choke (opening the hatch etc). Heading to San Diego for work tomorrow, but home over the weekend to check these things out. It does
start like a champ when warm.

Also, I'm not sure I hear a fuel pump go on. another thing I'll check on. And, i'll finally get to that fuel filter.

-kelly

--
1978 Kingsley
Putney VT

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Thank you for the suggestion. when you say engine heat, do you mean from cranking the starter? When it's warm it starts perfectly; just trying to
make sure I understand.
When I first got the coach I constantly flooded it- like a newb
-kelly

If that is the case here, I stab the accel pedal several time to force feed some fuel into the carb throat with the accelerator pump. THEN push pedal
to floor SLOWLY to set the choke's fast idle setting and MAYBE this will solve your problem.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~~ k2gkk @ hotmail dot com ~~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ex-Palm Beach, 76 ~ ~ ~
~~ k2gkk + hotmail dot com ~~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
______________
*[ ]~~~[][ ][|\
*--OO--[]---O-*
________________________________________
--
1978 Kingsley
Putney VT
 
The procedure I suggested is for COLD start. However, heat from the running or warm engine MAY cause fuel to evaporate from carb AFTER engine is shut down which COULD cause your later hard start from cold.

Good luck!

Mac in OKC

________________________________
From: Gmclist on behalf of kelly stockwell
Sent: Sunday, August 6, 2017 20:39
To: gmclist
Subject: Re: [GMCnet] starting the engine

Thank you for the suggestion. when you say engine heat, do you mean from cranking the starter? When it's warm it starts perfectly; just trying to
make sure I understand.
When I first got the coach I constantly flooded it- like a newb
-kelly

If that is the case here, I stab the accel pedal several time to force feed some fuel into the carb throat with the accelerator pump. THEN push pedal
to floor SLOWLY to set the choke's fast idle setting and MAYBE this will solve your problem.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~~ k2gkk @ hotmail dot com ~~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ex-Palm Beach, 76 ~ ~ ~
~~ k2gkk + hotmail dot com ~~
~ www.gmcmhphotos.com/okclbhttp://www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
______________
*[ ]~~~[][ ][|\
*--OO--[]---O-*
________________________________________
--
1978 Kingsley
Putney VT
 
The cold start procedure is always the same: turn key to Run, press the
pedal once to set the automatic choke, then turn key to Start with foot off
the pedal.

If the carb is dry (from boiling out after the last shutdown, as D.C.
describes), and the engine uses a mechanical pump, one must crank the
engine long enough to pump fuel into the carburetor.

If the carb is dry and the engine uses an electric pump, the carb bowl will
start to fill when the key was first moved to Run.

If the carb has fuel, the engine will start, no matter what kind of pump it
uses, assuming the choke works and is set properly.

That can be tested. With the engine cold and the air filter housing
removed, press the gas pedal once. The choke plates should close and stay
closed, and the high-idle cam (between the choke stove and the carb body,
on the starboard side of the carb) should position itself to the high lobe.
If it doesn't, loosen the screws on the coke stove (which hold in the
Bakelite part) and rotate it until it just sets the high idle during that
one press. (You can reset the automatic choke to test it again by pushing
the high-idle cam to the low lobe while the gas pedal is slightly
depressed, using a small screwdriver.)

If the engine is hot enough that it won't engage the choke, start by
holding the gas pedal halfway down and turning the key to Start.

Rick "easier to adjust than it sounds" Denney

On Sun, Aug 6, 2017 at 11:25 PM D C _Mac_ Macdonald
wrote:

> The procedure I suggested is for COLD start. However, heat from the
> running or warm engine MAY cause fuel to evaporate from carb AFTER engine
> is shut down which COULD cause your later hard start from cold.
>
--
Rick Denney
73 x-Glacier 230 "Jaws"
Off-list email to rick at rickdenney dot com
 
For cold start problems you can check 2 main issues relatively easily with the hatch open and air cleaner lid removed and the engine OFF.;
1) choke operation - before you touch anything else, while the engine is still cold, simply press the gas pedal one time all the way to the floor. The
choke plate should fully close. If the choke plate is even partially open you have some linkage adjusting to do. If it does not close fully it will
be very hard to start COLD (engine is at ambient temp).
2) check for fuel in the float bowl. You can do this by pressing the gas pedal and looking down the primary bores of the carburetor, but NOT while
cranking! Just with the engine off you should see two small streams spray as you move the pedal - assuming your accelerator pump works properly. If
there is no "pump shot" either the bowl is empty, the accelerator pump is bad or both. The fuel can "go away" from the float bowl for two reasons; a)
the engine was very hot last time you shut it down or it's been several days - in either case the contents of the float bowl evaporated. b) the well
plugs on the underside of the float bowl leak and the contents drip into your intake manifold (can be fixed with epoxy). In either case you must
crank for several seconds to fill the bowl back up. Running the electric pump for 5 -10 seconds before cranking will help wth this.
Finally I would not recommend cranking the engine for more than 10 seconds at time with a 20 second wait before recranking. Cranking longer will
overheat the starter and shorten its life.
--
Chris Geils - Twin Cities
1978 26' Kingsley w/ very few mods; Headers, Progressive Dynamics 9040, aux trans cooler, one repaint in stock colors, R134a, Al rad, 50k mi
 
This won’t be any help - but I haven’t posted in a long time and I feel like tossing in 2-bits.

One of the first things I had Jim K’s guys install was an electric fuel pump. Turn the key and I could hear that woodpecker come to life. I was going to mount some rubber isolators on the frame so I wouldn’t have to listen to it until one day, when the coach didn’t start, I realized the woodpecker wasn’t home! I shinnied under the frame and found a loose connection. Peck-peck-peck I was running again.

I’ve never made friends with a carburetor, so I finally decided to install the Howell EFI with EBL and electronic distributor control. Over the past 2 1/2 years I haven’t given the motorhome much love, but when I go to start it up and give a run, it starts on the 3 revolution of the engine. Every time.

Oh - also the engine never does that embarrassing run-on after the switch is off, and there’s no such thing as vapor lock, so far.

So the take-away for me was to update to ’90’s technology to make up for my poor shade-tree mechanical skills.

Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, CA
Howell EFI + EBL + Electronic Distributor
 
I kinda think of the old school carbs as an anti theft device- people who came up with fuel injection and electronics have no idea thow to finesse a
carbed vehicle to start when its balky. In a similar fashion, having a manual trans or especially a 3 on the tree? Few know how to drive them
anymore.

Might want to chaeck if you have the lectric pump wired to an oil pressure switch. If so, it wont come on unles the engine is cranked enough to get
to ~5-10#
Its handy to have an over ride switch on the run circuit- lets you prime the bowl after sitting
Qjets are notorious for leaking down the fuel bowls via the press in plugs at the bottom.
--
76 Glenbrook
 
If the PO used an oil safety switch, turning on the key will not energize
the electric fuel pump unless a priming circuit has been installed.

On Mon, Aug 7, 2017 at 3:24 AM, Chris Tyler
wrote:

> I kinda think of the old school carbs as an anti theft device- people who
> came up with fuel injection and electronics have no idea thow to finesse a
> carbed vehicle to start when its balky. In a similar fashion, having a
> manual trans or especially a 3 on the tree? Few know how to drive them
> anymore.
>
> Might want to chaeck if you have the lectric pump wired to an oil
> pressure switch. If so, it wont come on unles the engine is cranked enough
> to get
> to ~5-10#
> Its handy to have an over ride switch on the run circuit- lets you prime
> the bowl after sitting
> Qjets are notorious for leaking down the fuel bowls via the press in plugs
> at the bottom.
> --
> 76 Glenbrook
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Bruce Hart
1976 Palm Beach
Milliken, Co
GMC=Got More Class
 
Thanks again!

I'm sorry I won't be able to report back my results until Saturday... but I've got an excellent idea of what to look for

cheers
kelly
--
1978 Kingsley
Putney VT
 
1) If it worked properly last year but not now, it could be gum on the linkages moving parts and fast idle pivot. I like WD-40 for this as it cleans
and disolves and leaves a touch of light lube. Manuals say "do not lubricate" as they don't want the lubricant itself to gum, but rebuilders recommend
WD-40 to clean and preserve the finish.
2) if it starts then falters after a few seconds then the choke vac pull off needs adjustment, replacement, or the 1" vac hose feeding it replaced.
When set right it should transition almost like EFI. This is a very fine adjustment but makes a huge difference when correct. The pulloff cracks the
choke open in the seconds after it starts a set amount so it won't choke out.
3) you may have developed bowl plug leaks in the that need epoxy.
4) after sitting a few weeks longer cranking times are normal with a stock setup. If this happens every morning on a trip, check 1, 2, 3 above.
5) one final overlooked thing that is a quick cold engine off test is to be sure the choke unloader is set correctly. With choke now working and a
cold engine and air cleaner lid off, set the choke with one full pedal press. Now press the pedal to the floor and in the last 1/2" or so of pedal
pressure you should see the choke rotate open about 1/4". This is the "clear flood" setup where if flooded you hold pedal fully down and crank per the
manual. However for this to work your pedal cable has to be fully opening the throttle in the first place.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
engine hatch open, air cleaner cover off.

I push the pedal, i hear something but nothing moves that I can see (the top plate toward the front is the choke, right?)
smells like raw fuel in there but i don't see any. it's been sitting for a week now

will try to upload a photo

--
1978 Kingsley
Putney VT
 
Theres SO much to learn, at least you're trying :D

Yes the open plate is the choke, if the engine is cold it should be closed to make the engine start better.

look own through the choke opening and there will be a plate, called a butterfly, that moves when you push the gas pedal.

There is another one under the one in back that is closed, so one on top and one further down, but the top one won't open until you floor it while driving.

The 'choke plate' in back is the vacuum secondary. It only opens when / if the gas pedal is way down and the engine is under load. It's near impossible to get to open sitting in the driveway

The green thing looks like a vacuum filter or check valve

________________________________
From: Gmclist on behalf of kelly stockwell
Sent: Sunday, August 13, 2017 2:35:51 PM
To: gmclist
Subject: Re: [GMCnet] starting the engine

something under that top plate is moving

but it doesn't stay. I pull the chain or push the pedal it moves but then comes back to the resting spot

http://www.gmcmhphotos.com/photos/member-galleries/p63532-img-24144.html

what's the small green thing? is that a vacuum line or fuel?

i'm so ignorant
--
1978 Kingsley
Putney VT

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Unsubscribe or Change List Options:
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Ok, so i'm right about what the choke is, and that the green thing is in a vacuum line

Now, how is the pedal going to the floor (once) supposed to close the choke? I can move things but I don't know what should move together, what
should move the lever that moves the choke flapper?

I'm not having luck looking at images online for what moves what plates.

And finally, there's supposed to be a tiny gas filter in the carb, looks like a small gold microphone.

how do i get to/change that?

thanks
kelly
--
1978 Kingsley
Putney VT
 
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