Cat 3208 injector pump

[ajo]

My venerable 3208 came down with a serious case of "No-Start" a fer days ago and after much diligent searching your post percolated to the top of the heap. Between your comments and those of my local mechanic I went to work...

I have learnt at least two important lessons and a few facts:

The official CAT Service Manual(s) and Parts books are poorly indexed and
the various specification tables are incomplete.

There is no comprehensive theory of operation chapter.

To be lifted into the run position the ON/OFF fuel control lever depends
upon Fuel Pressure *provided by the [external] "fuel transfer pump"* as
well as the magnetic attraction of the armature of the energised fuel
cutoff solenoid. However those two points of functionality are not
mentioned anywhere and are easily overcome by whatever is/was causing the
stickiness in the rack within the injector pump mechanism.

Several articles I read from other people with this same problem danced
around various fixes without addressing the functionality or if any of
their fixes actually worked.

"Tromp on the foot throttle while cranking is what usually works for me."
"The engine should start and run with the cut-off solenoid removed, if it
doesn't then you know it prob'ly know isn't the solenoid."

Allan had the best advice: Hit it with a hammer. Well, I never got that
far. But I did add a cup of injector cleaner to the secondary fuel filter
and then forced the motor to start by lifting the lever with my specially
designed custom lever-lifting tool. Then I worked the throttle a dozen
times and shut down.

The spec for Fuel Transfer Pump pressure requirement is buried in the
Troubleshooting section on pp54 of one copy of the two Service Manuals I
have. "...3psi at cranking speed." Whilst measuring that pressure--with the
motor NOT running--I determined that my primary fuel pump is working and
that the primary and secondary filters are good enough. Then, I observed
the fuel control lever lifting on its own into the run position. That was a
dandy good sign. The cleaner did some good. Hammer unnecessary.

I had also observed that the magnet of one of those extendable magnetic
screw-picker-upper tools is enough to lift the lever. So I tested the
solenoid and determined that the armature becomes quite a strong magnet
when energised. Together, both of these forces--fuel pressure and solenoid
electro magnet--were not enough to pull the lever up against the stickiness
of the rack within the injector pump. /That was the whole problem to begin
with/. However after the second application of injector cleaner and
reinstallation of the cutoff solenoid the motor started normally thrice.

So I wonder, at this point years later: Did you get your 3208 to start?

--ajo

Tourists don't know where they've been.
Travellers don't know where they're going.
--Paul Theroux