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Long-Backfire damage and tubing flares

To: tigers@autox.team.net
Subject: Long-Backfire damage and tubing flares
From: James Barrett <jamesbrt@mindspring.com>
Date: Mon, 22 Jan 2001 09:55:46 -0500
Folks,
        Friday morning I headed for work and decided to
see if I still had a slight backfire on acceleration.  Well,
I should not have done that. KABAMMMM !!  The motor died
and would not restart in neutral.  I rolled into a DOALL
parking lot and stopped.  Tried to start it again and the
loudest explosion I have ever heard came out of one tail pipe.
I figured that I had an Ignition problem as I just receintly
installed a MSD 6AL on the Tiger.  I have a stock magnetic
pickup Ford distributor.
        Pulled the distributor cap and noticed that the rotor
was loose and rotated several degrees from normal.  Checked the
inside of the rotor and found that the plastic locator had
mostly sheared off.  No sign of contact with the distributor 
cap.  Was able to get the rotor back in the slot of the
distributor shaft and it appeared that it might hold until
I could get home and replace it.  
        About that time some guy drove up wanting to look 
at the Tiger.  That took a while.
        Replaced the distributor cap and cranked it.
No joy.  Pulled the cap and using a screw driver near the
magnetic pickup I determined that the MSD and the pickup
were working.  Got nice fat spark off of the coil wire.
        Cranked a bit more with the cap off and noticed the
distributor/rotor was NOT turning. @#$!^%$#@!
        About that time DOALL opened and I was allowed to use
their phone to call a wrecker.  DOALL is an industrial
supply house for bandsaws ( up to 2 1/2" bands), all kinds of
machining tools and accessories, taps, dies, drill bits,
chemical, etc. and flaring tools.  I promply ordered a RIDGID
flaring tool for about $45.  Will let you know how that turns
out.
        Short tow home and a call to work that I wouldn't be
in.  A gallon of oil dry added to the drive way where the wrecker
dumped a couple of quarts of oil.  At least it was clean oil.
They have one very bad leak.  I assume that they add a few quarts
of oil before every towing job. By the way this was the very
first time my Tiger has ever been towed. 

        Pulled the distributor and 3 teeth were off of the
distributor gear.  Checked the cam gear and it appeared to be ok.
        
        Pulled the oil pan and found two teeth.  Pulled the
oil pump so I could remove the windage tray.  Found the third tooth.
Also noticed a full 1/2 spirial twist to the oil pump drive shaft.
The oil pump was locked solid as well.  Got the rotors out of the
pump and  the two parts are stuck together.  There was no crud
that locked up the pump. It is as if the internal rotor had moved
slightly to one side and jammed its self into the outer rotor.
There appears to be a tiny flat at the peak of the inner rotor
where it is stuck to the outer rotor.  Plan to use the rotors
and drive shaft as a paper weight in my office.  There was no sign
of any scratches on the parts and the oil, all 14 quarts was
clean.
        Had a good distributor gear from the older point type
distributor.  The broken gear had also sheared the roll pin
so I had to use a cut off wheel to remove the broken gear.
Found some gauling on the distributor shaft under the gear.
By spinning the shaft with my electric drill I was abke to
smooth the shaft.  Forgot that the roll pin hole is off set
on a Ford so I of course pressed the replacement gear on wrong.
Was able to rotate 180 and put the roll pin in.  Distributor
now fixed.
        New high volumne oil pump, pickup tube, drive shaft,
pan gasket, RTV, 24 quarts of 20-50 oil and a rotor went
for $120.  Called in the order and was able to get the parts
Friday night just before they closed.  Checked the pump,
drive shaft, pickup tube and gaskets to be sure they were
correct.  Didn't check the rotor.  Dumb Ass parts man gave
me a GM rotor.  Fortunally I had an old rotor that was still
OK. 
        Got everything back together and decided to adjust
the valves. (Have Harlin Sharp Roller Rockers and screw in
studs on this 4 barrel Cleveland).  Released the rocker,
gently tightened the nut until the pushrod could not be rotated
with gentle finger pressure, then took one more full turn of the
nut and locked it with the allen screw.  I believed that I had
had the motor rotated properly for each valve adjustment.
        Back together with eyeballed timing of the distributor
and started it up.  Ran like crap.  Kept it running until it
started warming up .  My wife came out and said " What is that
dripping under the Tiger?".  Shut it off looked under, Had the
Tiger up on Jack stands) lots and lots of liquid.  Assumed that
the rear of the oil pan was leaking until I smelled the fluid.
GASOLINE, about a couple of quarts was on the floor and more was
dripping on the now hot headers!  Fortunally I was able to mop
up the mess without burning down the Tiger, garage and house in
that order.  I have a fire extingusher in the garage and it is fairly
big, but that much gasoline would have been a lost cause if
it had ignited.
        Turns out that the less than year old 3/8" steel fuel line
had rubbed on the aluminum intake and wore a hole through the
tubing.  Not a mark on the aluminum manifold.  I assume that the
vibrations due to the Holly Red fuel pumping caused the tubing
to vibriate continiously at that point.   Fixed that  problem.
Adjusted the timing to 10 before and the Tiger had very rough idle.
        I assumed that the backfire that I had previously
experienced on acceleration was due to the need for more
fuel.  I have a 650 double pumper with  pink accelerator pump
cams.  I remounted the cam to the #3 position. ( which I now
believe to to be wrong with even less pump shot)  All the other
cams have 2 holes and #2 provides a bigger shot of fuel than #1
which is the normal factory setting.  On this cam the fuel map
for the # 2 position was not in the Holly book.  Probably
will change  to position 2 as soon as I can.  Of course this
working on the carb messed up my throttle linkage so a few hours
working on that.  
        Drove to work Monday and the Tiger was VERY rough.
Soft backfire through the tail pipes even when I just barely
accelerated.  Held up traffic I was so slow.
        Last night did a "short the plug test" and found that
#1 and #6 cylinder had no effect on the running.  Plug on #6
had an open circuit and plug #1 was shorted.  Replaced the plugs
and still no luck.  Did a compression test and found zero pounds
on number 1, all others were 170 to 180 psi.  Re adjusted the
valves on #1 and got 175 psi. Idle nice and smooth now.
        About to go to work on Tuesday, wish me luck.


                

        
James Barrett Tiger II 351C and others

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