Mitsubishi Express starting issues ... help!
who where
developed an "interesting" problem - warm starting, or more precisely
warm non-starting. Prior to this, it has been an uber-reliable
vehicle.
Cold starts are not an issue (*).
Hot starts are not an issue.
Park the vehicle hot and restarts within ten minutes not an issue.
BUT, park the vehicle hot and wait 20-40 minutes and it just spins
over on the starter, no sign of firing, not a single pop or fart.
Healthy spark from HT "king-lead". Plenty of signs of flooding. Only
way to start it is ... wait. Actually, we have roll-started it (handy
to live on a hill, but we can't take that with us) and it takes a fair
bit to clear the excess fuel. The exhaust verifies it was flooded.
Initially suspected the auto-choke was playing up, as when the
no-start behaviour is happening the butterfly is closed. these carbs
use water-heating for the auto-choke, and I wouldn't have expected it
to revert to fully closed that quickly especially as heat soak in a
forward control van keeps that area quite "warm". I tied it fully
open against the spring tension, but apart from abysmal perfromance
for a couple of minutes after cold starting it had no effect on the
flooding behaviour.
Analysing the classical non-electrical flooding causes - float level,
blocked air cleaner, stuck a-c etc - doesn't shine a light for me on
any one that would be so dramatically different <10 mins vs 20-40 mins
after shutdown.
No, I haven't pulled the carb apart yet. I was hoping to have a clear
idea what I was looking for before embarking on that exercise. I
don't look forward to a pull-down_look-around_reassemble_test cycle as
the testing requires a fair amount of time to establish whether
anything has changed, so trial-and-error is going to be a PITA.
All constructive suggestions welcomed.
(*) Cold starts are OK, but after taking off it usually plays
silly-buggers about when I hit throttle in third on a normal getaway
(normal entails close to WOT as these aren't powerhouses). It loses a
lot of grunt and almost feels like it is seriously over-rich or
seriously lean, hard to tell which. Using moderate throttle for the
first 2 minutes avoids this behaviour. Relevant?
atec77
months back it sucked a lock tab into the carb and it was nigh invisable
but it would vary through running ok to really badly , the mu metal was
melted over the bottom butterfly shaft and somehow partiall blocked some
air bleeds and stuff , it might be worth rebuilding the carb as a start
as his problem effected petrol and gas , it was a pita
--
X-No-Archive: Yes
Clocky
You can safely ignore that mess of a post.
Clocky
Does the carb have a sight glass where you can check the float level?
I've known problematic anti-dieseling solenoids to give similar problems
(looks like a round metal or plastic thing on the carby with an electrical
wire on it) so check that but it's likely the carb needs a good clean and
the float level adjusted and checked to make sure the needle and seat are
shutting off properly. If the needle and seat are weeping through, the carb
will fill with fuel over a period of time when stopped due to residual fuel
pressure so when you go to start it again the engine will flood straight
away.
If the carb fuel inlet has a rubber fuel hose, try clamping it off when you
stop the vehicle (to prevent fuel filling the carb resevoir), and then see
if it starts normally after a period of time where it would normally play
up.
Rob
Just check the electrics for a start, plugs, leads, Points??, more than
likely its here where the problem lies.
Then next with the filters then carby.
John_H
>
>Analysing the classical non-electrical flooding causes - float level,
>blocked air cleaner, stuck a-c etc - doesn't shine a light for me on
>any one that would be so dramatically different <10 mins vs 20-40 mins
>after shutdown.
>
>No, I haven't pulled the carb apart yet. I was hoping to have a clear
>idea what I was looking for before embarking on that exercise. I
>don't look forward to a pull-down_look-around_reassemble_test cycle as
>the testing requires a fair amount of time to establish whether
>anything has changed, so trial-and-error is going to be a PITA.
>
>All constructive suggestions welcomed.
I'm not familiar with your model but presumably it's got a mechanical
fuel pump?...
In which case I'd probably go for the carby needle and seat (which
ought be easy to replace in isolation). Careful visual inspection,
after you've removed it, ought confirm a likely problem (assuming the
two come apart).
--
John H
who where
wrote:
I wish.
>I've known problematic anti-dieseling solenoids to give similar problems
>(looks like a round metal or plastic thing on the carby with an electrical
>wire on it) so check that but it's likely the carb needs a good clean and
>the float level adjusted and checked to make sure the needle and seat are
>shutting off properly. If the needle and seat are weeping through, the carb
>will fill with fuel over a period of time when stopped due to residual fuel
>pressure so when you go to start it again the engine will flood straight
>away.
That at least offers a mechanism for "slow flooding", which is what I
was having trouble finding. All the others were more or less suction
related.
>If the carb fuel inlet has a rubber fuel hose, try clamping it off when you
>stop the vehicle (to prevent fuel filling the carb resevoir), and then see
>if it starts normally after a period of time where it would normally play
>up.
Yes, it is hose AFAIR (it isn't here now - one of the kids has
borrowed it for the weekend for a trip to Collie, motorbike stuff).
I'll probably have to replace it before trying that as I wouldn't
think it would take kindly to that level of compression without
complaint.
Once upon a time (grey motor days) I had all the jets, removal tools
etc for the olde Strombergs. Bit before your time I suspect. Still
have one of the aftermarket adjustable mains here somewhere. But I
don't have any of the carby service bits for more "contemporary" stuff
which is why I was looking for a start on what to look for.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
As an aside, we did a valve clearance adjustment (shims) on his
recently acquired CRF450R the other day, after a dyno run gave it 42hp
vs the book 50hp. According to the factory manual, TDC is supposed to
be located using marks on the end of the crankshaft. Lad was on that
end while I was eyeballing the camshaft gear marks. He says "that's
TDC" and I said "can't be, that's 1/2 a tooth out on the camshaft gear
unless the chain is horribly stretched".
Used the old screwdriver_down_the_plug_hole method and put it at TDC
and the cam gear was out exactly one tooth. After reshimming the
followers and reinstalling the cam gear, it now produces just over 50
on the dyno. He's chuffed. 36 teeth on the cam gear (10deg, or 20deg
crank per tooth). Can but wonder whether the off timing contributed
to the previous owner selling. It was also a c##t to kick-start.
D Walford
When its playing up have you tried starting with the throttle fully open?
Usually flooded engines will start with a bit of cranking if you hold
the throttle fully open.
If it does start blowing lots of black smoke it confirms that flooding
is the problem, if its still won't start you will need to look for
another cause.
How long since you serviced the spark plugs etc?
Daryl
Scotty
"who where" wrote in message
news:tei4275bjmanr5qot...@4ax.com...
We have a 1996 Express (4G63 with Mikuni carb) that has recently
developed an "interesting" problem - warm starting, or more precisely
warm non-starting. Prior to this, it has been an uber-reliable
vehicle.
--------------------------------------------------------------------------------
I had that same issue with a Mitsi Van. It turned out to be simply the
throttle pump on the carbie. There was a rubber seal (or diaphragm) that had
perished. From memory (This was years ago) it cost around $35 for a new
throttle pump and away it went.
Worth a look eh.
who where
<dwal...@internode.on.net> wrote:
>When its playing up have you tried starting with the throttle fully open?
>Usually flooded engines will start with a bit of cranking if you hold
>the throttle fully open.
Geez Daz I've been around long enough to know to do that ;-)
Yes, and I've even tried "bricking" the pedal so it doesn't pump more
than the once it takes to get it to the floor. Still just spins over.
You can leave it like that for 5 miutes or more, and then when you try
again it just ... spins over.
>If it does start blowing lots of black smoke it confirms that flooding
>is the problem
Indeed it does, WHEN it eventually will actually fire.
>if its still won't start you will need to look for
>another cause.
>How long since you serviced the spark plugs etc?
They are about 15,000 old. All just recently pulled (and THAT is a
c##t of a job on these - remove driver's seat, remove floor section,
remove inlet air plumbing, ...) when this started, gaps checked, good
condition.
But thanks for the suggestions.
who where
>Just check the electrics for a start, plugs, leads, Points??, more than
>likely its here where the problem lies.
Obviously you missed the bit "Healthy spark from HT "king-lead"."
That sort of eliminates all the LT considerations. Plugs fine, see
reply to Daz. Dizzy cap all good. Leads all good and clean..
>Then next with the filters then carby.
Fuel filter? Can't see how that would cause flooding.
Air cleaner element is OK. Have even tried running without it just in
case. Again, if inlet air blocked the flooding would be as bad or
worse when hot - not behaving as it does after significant cool-down
only.
who where
>I'm not familiar with your model but presumably it's got a mechanical
>fuel pump?...
Yes, wedged in/under the "armpit" of the inlet manifold. Not easy to
access either - had to replace one on a SD Express (the one we had
before this SJ model).
>In which case I'd probably go for the carby needle and seat (which
>ought be easy to replace in isolation). Careful visual inspection,
>after you've removed it, ought confirm a likely problem (assuming the
>two come apart).
Pulling the carb apart is on the agenda when the vehicle is returned.
What a pity they don't put windows in carbs on these, would make
diagnosis that bit easier.
who where
wrote:
So it just bled from the bowl into the inlet manifold? Hmmmm.
>Worth a look eh.
Indeed.
John_H
>On Sun, 17 Jul 2011 16:43:34 +1000, John_H <john...@inbox.com> wrote:
>
>>I'm not familiar with your model but presumably it's got a mechanical
>>fuel pump?...
>
>Yes, wedged in/under the "armpit" of the inlet manifold. Not easy to
>access either - had to replace one on a SD Express (the one we had
>before this SJ model).
FWIW I'm not suggesting the likelihood an issue with the pump...
merely the effect the type of pump will have on a leaky needle and
seat.
--
John H
Rob
> On Sun, 17 Jul 2011 16:37:24 +1000, Rob<mesa...@gmail.com> wrote:
>
>> Just check the electrics for a start, plugs, leads, Points??, more than
>> likely its here where the problem lies.
>
> Obviously you missed the bit "Healthy spark from HT "king-lead"."
> That sort of eliminates all the LT considerations. Plugs fine, see
> reply to Daz. Dizzy cap all good. Leads all good and clean..
>
Not necessarily. have done a bit of work trying to sort this type of
problem
Did the Carby OHaul and a new fuel pump fuel filter. It did relate back
to the electrics
90% of all problems relate back to the electrics them when you are
satisfied that's OK then you start on the fuel side.
Think about it when it happens - does not indicate the carby.
who where
>On 17/07/2011 6:30 PM, who where wrote:
>> On Sun, 17 Jul 2011 16:37:24 +1000, Rob<mesa...@gmail.com> wrote:
>>
>>> Just check the electrics for a start, plugs, leads, Points??, more than
>>> likely its here where the problem lies.
>>
>> Obviously you missed the bit "Healthy spark from HT "king-lead"."
>> That sort of eliminates all the LT considerations. Plugs fine, see
>> reply to Daz. Dizzy cap all good. Leads all good and clean..
>>
>
>
>Not necessarily. have done a bit of work trying to sort this type of
>problem
>
>Did the Carby OHaul and a new fuel pump fuel filter. It did relate back
>to the electrics
>
>90% of all problems relate back to the electrics them when you are
>satisfied that's OK then you start on the fuel side.
That's where I went first up, but can't fault the electrics so I have
been targetting the fuel system.
>Think about it when it happens - does not indicate the carby.
Except the smell of excess fuel is there from the first spinover when
the problem occurs. Otherwise I'd agree.
But I'm not about to start shotgunning the electrics by replacing
everything in sight when I can't find a fault there. The "when it
happens" is why I'm here asking. As I mentioned, none of the
"classical" flooding mechanisms fit the behaviour although the
"pressurised fuel line bleeding slowly into the system" might be it.
One aspect of the electrics of Japanese vehicles of this vintage (and
later) is the incredibly scrawny cables in their harnesses. Replacing
the main harness would be a fun pastime, not.
Clocky
If he's talking about the accelerator pump then the symptom would be a
massive flat spot on acceleration especially after the vehicle has warmed
up, not so much hard to start when warm.
who where
wrote:
Certainly doesn't suffer from that. No hesitation at all - not that
it shoves you back into your seat either when you floor it.
Rob
I would have check it out on an oscilloscope.
Albm&ctd
Mitsubishi shit, ah fuckit I forgot, I have one 99 model that has the ha bloody
ha "electronic control type carburetor". Basically an electic choke and and a
few other bits.
You car is fuck*d bro, get over it :-)
Al
--
I don't take sides.
It's more fun to insult everyone.
http://kwakakid.cjb.net/insult.html
ti...@beerlover.com.au
> Have you tried dancing nude around it?
> Mitsubishi shit, ah fuckit I forgot, I have one 99 model that has the ha bloody
> ha "electronic control type carburetor". Basically an electic choke and and a
> few other bits.
> You car is fuck*d bro, get over it :-)
reliable.
who where
Actually there is a world of difference between the Mitsi vans and
their cars of the 80's/90's in particular. The vans were all J-vins
(full import Japanese built) and were IMHO better built than the Tojo
vans of that era.
Before the SJ we had an SD and that was also uber-reliable.
I expect to see the van again this weekend for further diagnosis and
testing.
Noddy
> Actually there is a world of difference between the Mitsi vans and
> their cars of the 80's/90's in particular. The vans were all J-vins
> (full import Japanese built) and were IMHO better built than the Tojo
> vans of that era.
Absolutely.
There's been a number of Express vans in my immediate family (both mine
and those belonging to relo's) and they were all stellar vehicles. I
also had a service contract for the things when Australia Post ran them
and I always found them to be a first class vehicle that would give
*anything* in their class *more* than a run for it's money.
In fact, I *hated* the SF Express for a while when Australia Post ran
them as they hardly ever caused a problem and I made very little out of
them. When their lease ended they switched from Express vans to Transits
(fuck only knows why) and I went from eating cardboard to caviar in one
fell swoop :)
Given the choice between a Hi-Ace and an Express I'd take the Express
every single time.
> Before the SJ we had an SD and that was also uber-reliable.
They were, and the 4WD variant was pretty amazing.
SD front ends are proving *very* popular with hot rod builders as being
one of the better "self-contained" independent front ends that comes in
a relatively compact package that lends itself well to easy brake upgrades.
The average "street price" for an SD front end is around 300 bucks at
the moment, which almost makes the idea of hunting down old SD vans a
viable prospect.
> I expect to see the van again this weekend for further diagnosis and
> testing.
Sorry but I've missed a heap of posts this week as Telstra seems to be
having a massive problem with their news server. Do you have a problem
with an Express?
--
Regards,
Noddy.
D Walford
>> I expect to see the van again this weekend for further diagnosis and
>> testing.
>
> Sorry but I've missed a heap of posts this week as Telstra seems to be
> having a massive problem with their news server. Do you have a problem
> with an Express?
He's had hot starting problems, it smells of petrol and appears to be
flooded.
Daryl
who where
Not quite. Hot starting is never a problem, but give her 20 or 30
minutes of cool-down and it just spins over, no sign of firing
whatsoever. Mucho fuel smell, healthy spark, plugs good nick. Give
her another 20-30 and it starts again, with the expected clouds.
Suspected the auto-choke butterfly, which seemed "slow" to open fully
and quick to start closing. Tried wiring it full open, but apart from
making her a royal PITA when running cold it had absolutely no impact
on the cooling-down-starting behaviour.
(As I'm sure you'd know, the A-C is water-heated, mechanical fuel
pump, Mikuni windowless carb on the 4G63 2-litre donk.)
I still have some difficulty finding a fuel system mechansim that
would properly explain the cold=OK hot=OK cooling=schizehhausen
behaviour.
It was suggested that I *fully* eliminate electrics from the equation
before attacking the carb. Have dragged out the CRO and yesterday got
the van back from the #3 nipper. Decent switching waveform from the
dizzy reluctor at the coil. Parked in the 'shop, I ran it up to
operating temp and then tried to get the problem to reappear - no joy.
Went through this cycle several times yesterday. Only difference was
the engine bay was open, which obviously plays a different tune with
heat soak effects.
Every time it has played up "out there" (seeing it won't play up here)
I have popped the engine bay and have been able to draw a 1cm spark
from the king lead at the dizzy end. Dizzy cap/rotor/button all good.
Had considered the reluctor *may* misbehave under heat soak but the
ability to get the spark straight off - and yet not get any firing -
sort of dissuades me from blindly replacing it.
For now, stumped.
Albm&ctd
says...
Albm&ctd
says...
> Do you have a problem
> with an Express?
>
>
I 'heard' that the early Pajero diff fits, but I figure it most probably won't.