# [EVDL] Transmission is getting hot (motor too) and I use too much power...



## EVDL List (Jul 27, 2007)

Apologies in advance for the long post, but instead of
asking a short question and then subsequently posting
the info after each of you ask what the setup of the
vehicle is and what I noticed - here is as complete
as I could be in one post - with the main question at
the end of how to improve my efficiency:

OK, I am not a mechanic so I like a little advice.
I have been driving my "new" 1989 Ford Ranger conversion
for a few weeks, put almost 300 miles on it but I have
been struggling with the efficiency from day 1.
http://evalbum.com/4259
You may have seen my message saying that I took off the
power steering belt, because it was consuming too much
power and indeed the consumption reduced significantly
but the truck is still using almost twice the power
that I am used to from my previous S10 EV, which could
hold 55 on a level road at about 15kW of power as
reported by its WaveDriver AC controller. That consumption
gave that truck a 65 mile range on the freeway with a
110Ah 312V lead-acid pack.
When I try to maintain 55 in this truck the current
draw is almost constantly pegged close to 300A at 110V
so double what I expect. If I let up on the accelerator
and stay around 200V at 110-120V the speed will be
around 45 MPH. So, I need *more* power to go *slower* than
the S10, which tells me something is not right. The S10
was heavier (5000lbs with driver) compared to this Ranger
that tips the scales at 4400 with driver.

I trust the readings of Ford's meters, not only because 
they are reliable analog needle-style meters and connected
to the battery pack (expanded scale voltmeter) and across
the original shunt (Amp meter) but also because I have
pushed the truck to do just over 25 miles yesterday and
even though I was driving very conservatively the whole
time (at the end there was road work on the freeway, so
I could drop my speed from just over 50 to around 45 on
the last stretch) the voltmeter dropped quickly towards
the end, a few minutes after parking, the 120V pack had
recovered back to 118V, so I know it was close to empty.
Presuming that I can get about half the Ah out of this
pack of US-145 Golf cart batteries at this high current
draws, that means at least 120Ah at an average 110V and
presuming an average speed on the freeway of 50MPH the
power works out to 26kW to maintain that speed over the
time it takes to drive 25 miles and consume those Ah.
This means a whopping 528 Wh/mi which is also confirmed
by the fact that I charged at a ChargePoint a few times
and after driving less than 10 miles it needed over 7kWh
to recharge. Part of that is losses in the charger and
also part is losses in the battery charging at 130V
while driving it is done around 110V but it still comes
down to at least 500 Wh/mi at a lower speed than I was
doing with my S10 that consumed about half that
(270Wh/mi when doing constant 55 MPH)

Tonight on the commute home the drivetrain started making
a noise that I had never heard before. Luckily it mostly
was present with full throttle, so I backed off a little
and went home driving slower than usual (I don't really
like doing 45 on the freeway, even where the limit is 55)
and when I got home I touched the different drivetrain
parts to see if I could find a culprit. The motor was warm,
much warmer than I expect after a 15 min 10 mile easy drive
with constant speed. I keep the transmission in 2nd gear
so the motor does a tad over 4000 rpm at 50MPH, which means
that it is certainly not being lugged. There is a blower
pushing air through the motor and at the inlet side it
stays barely over handwarm, but I now felt the exhaust side
near the brush grilles and I could not keep my hand more 
than few seconds on it.

The transmission however was very hot. Not smoking, but I
could not touch it for more than a second. The transmission
has a small cooler in the front, immediately behind the open
grille, so I am wondering what causes the transmission to
get so hot - possibly the oil is low, as I have noticed a
small leak from around the fill/check tube - probably the
O-ring is busted and this was a known problem apparently
because I see some liquid gasket streaks around the point
where the pipe enters the pan, but the pipe moves when the
oil level is checked so that may have restarted the leak.

The diff was warm but I could comfortably keep my hand on it
so that is not the problem - it may need synthetic oil at
some point if it has not already, but that is not the issue
at this point.
I know that wheels are pretty well aligned and no brake is
dragging because even a small incline will cause the truck
to roll away.

I do not know if the brushes are properly advanced on this
motor, but knowing that it was converted by a company for
the city of Santa Rosa (converted by Pro EV in Penn Valley)
probably back in April 1996 judging from the sticker on the
controller (EV100 AKA EVT15, an IGBT forklift controller)
gives me at least the idea that the motor was installed and 
setup properly. The previous owner also commented that the
brushes looked like new, but I have reason to believe that
the truck has done less than 1000 miles as EV and 69k of
the 70k on the ODO were done before conversion. Reason that
I think this is because the controller reports now that it
has done 30 hours and when I got it almost 300 miles ago,
it was reporting 22 run hours. So I probably need to keep
an eye on the brushes and commutator to watch for signs
of overheating or damage from excessive sparking, in case
the brush advance was not setup correctly.

But the main question I have now is: what is the matter
with that automatic gearbox? How can it get so hot that
I cannot touch it after 15 mins of easy driving?
I am guessing that that is where most of my unexplainable
losses go.
I can see that there are slightly larger losses in the
tires (which are slightly wider than I had on my S10) and
possibly in the diff, depending if the oil is already
synthetic or not and of course the automatic transmission
will always have slightly higher losses than a manual
transmission.

BTW: I checked the vacuum hose that runs from the brake
system where the line from the vacuum pump and storage
vessel comes into a T and runs from there onto the 
modulator for this transmission, so it has vacuum at
all times (the power from this motor is never so high as
to require increased oil pressue in the transmission.
This transmission (A4LD) has torque converter lockup
though I am not familiar enough with tranmissions to know
if it will lock up above a certain RPM in every gear or
only in some gears.

I do know that first gear is very noisy, it sounds as if
it is straight cut when I accelerate to some speed, say
15 MPH which is just over 2000 RPM and let go of the
accelerator then I get a noticeable "engine drag" effect
combined with noiceable sprocket noise (a typical whine
from gear teeth) and both effects disappear when switching
to a higher gear. I do all my freeway driving in 2nd gear
and surface streets in 1st gear, so there is probably
something wrong with 2nd gear or with the entire transmission
if it consumes so much energy in an easy freeway drive as my
commute is less than 2 miles surface streets with usually
only 2 red lights before I reach the freeway, then over
7 miles straight road, followed by half a mile surface
streets with only 2 lights immediately after each other.

At this point I am ready to consider going direct drive,
because the diff has 4.10 ratio, so in direct drive setup
the motor will be doing 3620 RPM at 65 MPH and I remove
what looks like the biggest energy drain on this truck.
How can a 28 inch long hunk of metal warm up so much in
such a mild drive while it is even cooled by a small
radiator?
The consequence of going direct drive will be that the
low end torque will be less than when it can run in 1st
gear (2.47), but when almost half the energy is lost in the
transmission then removing it will more than make up for 
any loss of torque in 2nd gear (1.47 ratio).
If the transmission is removed, I will either need to extend
the drive shaft 28 inch to meet with the motor or move
the motor by 28 inch into the tunnel to meet with the
existing drive shaft.
Working on the drive shaft should not be the problem,
I have friends who can form metal and weld 
(and I understand the drive shaft needs to be balanced)

Suggestions or hints what to check if I do like to keep
the transmission for now? Or should I bite the bullet
and simply unbolt the transmission from the motor, then
mate the motor and driveshaft?
The transmission is definitely not running dry, even though
it is making strange noises - I now checked (cold and stopped
and I know that it should be checked hot and running) and
the level is 2 inch above "fill" level.
Or should I just go to pick-n-pull and get another transmission
bolt it in and call it a day?

I *really* would like to bring my consumption down to either
reduce charging time (for what I drive in my daily commute) 
or to extend my range (now max 25 miles apparently so I wonder
what will happen in winter)

Cor van de Water
Chief Scientist
Proxim Wireless Corporation http://www.proxim.com
Email: [email protected] Private: http://www.cvandewater.com
Skype: cor_van_de_water XoIP: +31877841130
Tel: +1 408 383 7626 Tel: +91 (040)23117400 x203 

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## EVDL List (Jul 27, 2007)

I wonder if the torque converter isn't locking up and is burning up lots of
power. 4000 RPMs in second gear would be heavy acceleration with an ICE and
wouldn't be a nice, efficient, low-reduction or locked operating mode. If
the losses are based on RPMs more than torque, an extra 10-15kW of losses
while accelerating hard wouldn't be a big deal like it is while cruising.

Also, is the transmission oil pump pumping at a higher rate/pressure at
higher RPMs? Is some of the energy being transferred to the transmission
lubricant then being dissipated as heat?

-Morgan LaMoore



> Cor van de Water <[email protected]> wrote:
> 
> > Apologies in advance for the long post, but instead of
> > asking a short question and then subsequently posting
> ...


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## EVDL List (Jul 27, 2007)

> Cor van de Water wrote:
> 
> > The motor was warm,
> > much warmer than I expect after a 15 min 10 mile easy drive
> ...


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