8v92 won't srart

[dmallorys]

Good morning. I am Doug Mallory and I have a 1988 pt 40 with a DDEC 1
8v92 detroit. Yesterday, the engine started fine and we drove @ 120
miles to a rest area on I84 west in NY. I put it into neutral, set the
brake and turned the engine off. About 20 minutes later I tried to
start it, but it will not fire off. It will spin freely, but won't
start. I called Coach Net and they sent a mobile mechanic out, but he
had no luck in getting it going. Coach Net then had me towed to a bus
garage who is suppose to look at it today. I was wondering if any of
you had any ideas as to why it will not start after running fine.
Thanks for any help.

Thanks Doug Mallory

[mbulriss]

Doug,

Sorry to hear of your problem. My rules of thumb are internal
combustion engines only need three basic things for them to run,
electric, air and fuel. If it spins freely and fast enough to start
the beast, we can probably assume (always a risk) the batteries,
grounds and cables are OK. Since it spins freely, are you really sure
you didn't hit the A/T switch by accident? That's about the main
other electrical problem.

Then are the fuel filters plugged? If you picked up a bad dose of
fuel, the 6V/8V will suck enough fuel to keep running, but when you
shut down for a break it may not re-start because a plugged filter may
only be 1/2 full of fuel. Ask me how I know that one! Nah, don't
bother. ;^) After the Racor, my 6V had 2 spin on fuel filters, the
8V has one. Drop the filter(s) to make sure they are full and clean.
If so, top them off with clean fuel and re-install. If not, change them.

Those seem the first obvious things to to me since you say it spins
freely. Notice I didn't mention much about air. I have no personal
knowledge of a 6v/8v not starting due to air filter plugged. In fact
trying to shut one down by plugging the air intake on the roof with
towels proved futile the one time I tried. They really suck air! -
Hence the emergency shut down pull cable on the older models.

After that, it's less obvious, like do you see oil pressure when
spinning it over? Seems like BB has a anti start feature if no oil
pressure, as I recall.

That's about all I can think of right now as first items. Good luck.
I am sure others with other experiences will chime in soon.

Mike Bulriss
1991 WB40 "Texas Minivan"
San Antonio, TX


--- In WanderlodgeForum@yahoogroups.com, "dmallorys"
wrote:
>
> Good morning. I am Doug Mallory and I have a 1988 pt 40 with a DDEC 1
> 8v92 detroit. Yesterday, the engine started fine and we drove @ 120
> miles to a rest area on I84 west in NY. I put it into neutral, set the
> brake and turned the engine off. About 20 minutes later I tried to
> start it, but it will not fire off. It will spin freely, but won't
> start. I called Coach Net and they sent a mobile mechanic out, but he
> had no luck in getting it going. Coach Net then had me towed to a bus
> garage who is suppose to look at it today. I was wondering if any of
> you had any ideas as to why it will not start after running fine.
> Thanks for any help.
>
> Thanks Doug Mallory
>

[ronmarabito2002]

As others have alluded to off and on, you begin with the simple
things. If it is spinning fine, check your filters and make sure they
are full of fuel. You might have an air leak and it allows the
filters to drain down. Next, check for loose wires to the DDEC, if
that's what you have. I would bet that it is something simple. Look
at your oil pressure sending switch at the rear of the engine, facing
you when the hatch is open. It will be on the block just under where
your a/c compressor belts are running. Make sure that unit is not
damaged and the wire is intact. There is a relay in the front load
center after removing the cover on the front of the coach. It
controls the fuel shutoff valve. Without going out and removing mine,
I can't tell you which one it is, but I can if you need me to. Not
sure where to go from there, but I'm still betting that it's simple.

Oh yes, it could be the neutral switch or wiring on the tranny.

R.E. (Ron) Marabito, Dallas, TX 92WB40



--- In WanderlodgeForum@yahoogroups.com, "dmallorys"
wrote:
>
> Good morning. I am Doug Mallory and I have a 1988 pt 40 with a DDEC 1
> 8v92 detroit. Yesterday, the engine started fine and we drove @ 120
> miles to a rest area on I84 west in NY. I put it into neutral, set the
> brake and turned the engine off. About 20 minutes later I tried to
> start it, but it will not fire off. It will spin freely, but won't
> start. I called Coach Net and they sent a mobile mechanic out, but he
> had no luck in getting it going. Coach Net then had me towed to a bus
> garage who is suppose to look at it today. I was wondering if any of
> you had any ideas as to why it will not start after running fine.
> Thanks for any help.
>
> Thanks Doug Mallory
>

[davidkerryedwards]

I concur with Mike. Most likely a fuel problem. Usually plugged filters give
some kind of
warning at higher speeds when high fuel flow is required so if you weren't
experiencing
this prior to shut down, I'd look into whatever controls fuel flow into your
engine, probably
an electric solenoid. You could bypass it with fuel in a container, or hot wire
it, or
manually engage it if possible to make sure it is working.

Kerry
82 FC 35
Denver

--- In WanderlodgeForum@yahoogroups.com, "mbulriss" <mbulriss@...> wrote:
>
> Doug,
>
> Sorry to hear of your problem. My rules of thumb are internal
> combustion engines only need three basic things for them to run,
> electric, air and fuel. If it spins freely and fast enough to start
> the beast, we can probably assume (always a risk) the batteries,
> grounds and cables are OK. Since it spins freely, are you really sure
> you didn't hit the A/T switch by accident? That's about the main
> other electrical problem.
>
> Then are the fuel filters plugged? If you picked up a bad dose of
> fuel, the 6V/8V will suck enough fuel to keep running, but when you
> shut down for a break it may not re-start because a plugged filter may
> only be 1/2 full of fuel. Ask me how I know that one! Nah, don't
> bother. ;^) After the Racor, my 6V had 2 spin on fuel filters, the
> 8V has one. Drop the filter(s) to make sure they are full and clean.
> If so, top them off with clean fuel and re-install. If not, change them.
>
> Those seem the first obvious things to to me since you say it spins
> freely. Notice I didn't mention much about air. I have no personal
> knowledge of a 6v/8v not starting due to air filter plugged. In fact
> trying to shut one down by plugging the air intake on the roof with
> towels proved futile the one time I tried. They really suck air! -
> Hence the emergency shut down pull cable on the older models.
>
> After that, it's less obvious, like do you see oil pressure when
> spinning it over? Seems like BB has a anti start feature if no oil
> pressure, as I recall.
>
> That's about all I can think of right now as first items. Good luck.
> I am sure others with other experiences will chime in soon.
>
> Mike Bulriss
> 1991 WB40 "Texas Minivan"
> San Antonio, TX
>