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Problem 1: It runs great over about 1900-2000 RPM, but
slowing down through that speed (a MAP of about 14) it begins to run rough and
requires an extra rich mixture to run at all. The MAP also goes up to
about 17 or 18 despite a fall in RPM. It is as if when the RPM gets low it
cant suck enough vacuum then the computer starts using the wrong part of the MAP
table. I am about ready to set the idle at 2000 and say problem
solved. Sound reasonable or is something wrong?
I'm willing to bet this
is still a tuning issue. The problem with trying to tune an erratic
running engine, is that the MAP keeps going up and down. It's difficult to
set the mixture at the MAP that needs to be set. I'm not sure I can offer
any sage advice to tuning this, mostly since I've forgotten the details of
tuning mine 6 months ago. Since I'll be doing it again this afternoon, I
may have a better answer later. Mine used to idle as low as about 1000
rpm, but I suspect the new setup won't do as well. Using Tracy's defaults,
the engine would only go as low as about 1800, but that's with no tuning
attempt.
Problem 2: I was very disappointed to discover that
turning off the alternator makes the engine barely run, especially with any
other electrical load, even with 2 batteries connected. They are
fresh healthy batteries. The voltage drops from 14.2 to 11.5. If
running at less than 2300 RPM when the alternator is turned off the engine
begins to surge or stops running all together (however, running on just one set
of coils improves the problem.) If running at higher RPM the engine will
just sag a little.
Hmmm, this sure doesn't
sound right. Turning off the alternator on mine has zero effect on the
engine operation, and that's just with one battery. In fact, losing my alt
fuse in flight was a non-issue also, though it would have been a bit more
serious if I hadn't noticed the low voltage (about 11.5 IIRC) on the
meter.
Think about your primary
power wiring a minute. Does the battery have a big beefy wire running to
the bus? When you turn off your alt, is there any chance that
your battery is being forced to feed the bus through a small gauge
wire? That would cause a voltage drop. When you turn off the
alt, is it just the alt, or a master switch of some sort? Will
this change the way the pumps, and ignition get there power, maybe from an
essential bus? As has been mentioned, an essential bus will be lower in
voltage, due to the drop across a diode. These are just some things to
think about.
This calls in serious issues about my electrical reliability.
I may decide to install a switch to disable one set of coils, or trading the
momentary switch that came with the EC2 to a regular 3 position switch.
Those LS1 Coils sure do seem to need a lot of Juice.
I installed full size switches
for my ignition disable function rather than the momentary switch that was
provided. I'd like to say that I did it for some grand reason, but in
reality, I didn't notice that Tracy sent the switches until after I had
installed the switches I had :-) Still, you just shouldn't have to do this
for the reason you're thinking. There has to be some answer for
#2.
Problem 3: (THE BIG PROBLEM) My coolant doesn’t seem to be
flowing well, despite the fact that I have no thermostat and have welded the
bypass passage in the pump housing. I ran for almost an hour at 3000 RPM
with no apparent problem. Going up to 4000 RPM after that the coolant
quickly overheated and boiled over. Surprisingly, the radiator was just
luke-warm.
I agree. This is a big
problem.
A) My AN-16 hose (engine to Rad) maybe is just not big enough – unlikely
because the fitting on the rad doesn’t even get warm.
AN-16 is plenty big. I'm only
running AN-12 now. Also, you noticed the cool fitting on the rad, which
was good troubleshooting BTW.
B) the Water pump sold to me by Adkins is really for a 3rd gen
and is running backward. – possible because the outlet side of the rad seems to
get warmer than the inlet side, but only slightly maybe and it is closer to the
turbo.
Does your water pump housing look
very similar to the one in the attached pics? If so, it's a 2nd
gen. I would expect that's what you would have received from
Atkins. How do your belts run? A second gen wp should run the
same direction as the eccentric shaft. A 3rd gen runs opposite.
C) I have a flap of rubber partially blocking the outlet hose.
D) The pump just refuses to properly prime itself.
Neither very likely. C is easy
to check, and D won't be a problem is the block is full of water.
E) Maybe the thermostat bypass passage is not properly welded closed. –
can’t see it because of the welded plate, will have to look with a dental
mirror. F) ???? any input or other ideas?
I was suspecting this as well.
Are you positive that the water outlet from the housing didn't get welded
shut?
Where is your water temp
sensor? What does it show?
Dave Leonard (still rather be working on these issues than shaping
that exit duct)
Shows you're a smart guy :-)
Good luck.
Rusty (off to the hanger,
finally)
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