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treerootCO
02-29-2008, 06:13 PM
The tailpipe emissions on my dad's 40 are so hot it will burn you. It doesn't backfire and as far as I can tell, it isn't excess fuel/cat issue. It just passed emmisions and HCs were at 30. I have also ruled out water/cracked block because it doesn't seem to steam on a cold day. Once it warms up the vapor goes away. The engine temp appears to be fine (will check with a temp gauge as soon as I buy one). No vacuum leaks that I can find except for an extremely small one on the front of the intake manifold. That one responds to ether ever so slightly if an excess is sprayed on it. We warmed it up and tightened the bolts a few times to the point it is almost gone.

I'll throw in a pic of the flaming ford problem because it makes me laugh...

http://www.autoblog.com/2007/03/27/video-ford-super-duty-diesel-throwing-flames/

Uncle Ben
02-29-2008, 07:12 PM
The tailpipe emissions on my dad's 40 are so hot it will burn you. It doesn't backfire and as far as I can tell, it isn't excess fuel/cat issue. It just passed emmisions and HCs were at 30. I have also ruled out water/cracked block because it doesn't seem to steam on a cold day. Once it warms up the vapor goes away. The engine temp appears to be fine (will check with a temp gauge as soon as I buy one). No vacuum leaks that I can find except for an extremely small one on the front of the intake manifold. That one responds to ether ever so slightly if an excess is sprayed on it. We warmed it up and tightened the bolts a few times to the point it is almost gone.

I'll throw in a pic of the flaming ford problem because it makes me laugh...

http://www.autoblog.com/2007/03/27/video-ford-super-duty-diesel-throwing-flames/

Only thing I can think of is o2 getting drawn into the exhaust somewhere. Might just be condensation? Mark the coolant recovery tank and see if it's using coolant.

Romer
02-29-2008, 07:35 PM
What if the pip is the run diameter or its running a muffler that isn't optimum? Have no clue.

treerootCO
03-02-2008, 10:18 AM
We worked on the truck into the night last night and cannot find anything wrong. Valves were hot lashed again. Went through the carb again and replaced the fuel filter. Took the time to disconnect every single straight manifold vacuum source. The EGR might have allowed us to idle a little lower so it will be replaced. It idles at 800 now but is not happy about it. It has developed a loping idle from 950 to 1100. We verified we are not 180 degrees off on timing. Rotor/distributor is solid with no wobble. Dwell is set to factory specs. The exhaust is all new from the engine back and doesn't seem to be restricted because of the force the air comes out the back. The coolant recovery tank is missing at the moment but the radiator is always full each time I check it.

Uncle Ben
03-02-2008, 11:44 AM
Does it have a cat converter? Wonder if it's partially plugged! That would create a bad idle and higher exhaust temps.

treerootCO
03-02-2008, 12:08 PM
I has a cat. How could you tell if it was plugged without cutting it off? The pressure coming out the tail pipe is about 1000 times what my 40 has. PortalTec said the solder joints on the logic board for the fuel solenoid could cause this so I am going to check that now. I am also going to remove the air rail feed to see if it is always on.

treerootCO
03-02-2008, 01:23 PM
I was 70 out yesterday! :D

treerootCO
03-02-2008, 02:04 PM
what do we have here?

RicardoJM
03-02-2008, 02:55 PM
what do we have here?

Dad's secret box for the stash. Don't think you were supposed to find it or figure out that the big bump is the where you push to open it revealing the treasured contents.













Sorry, couldn't help myself:D

treerootCO
03-02-2008, 05:43 PM
The board shouldn't have broken solder connections.

I think this fixed an intermittent stalling issue I had; however, it did not fix the idle problem

treerootCO
03-02-2008, 08:13 PM
Ran a compression test and every cylinder is at 120 psi + or - about a 1/4 of a pound. Drilled out the Cat and reamed all the honeycomb out to confirm the exhaust wasn't blocked. Ran up to Brighton and back at about 75mph....still won't idle. I did confirm the brake booster is dead so I blocked the port off for testing.