Running bad & lean

pila78

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At this point, I'm wondering if a lobe is gone on the cam. When I had the rocker covers off, all the valves seemed to working at full travel though..(?) I have a lead on the starter soleniod, coming up & attached to the heater hose, for easy access, for jogging the engine from above without it running etc, with a push button switch.. Very handy too.. I'm about to change the oil & filter. It hasn't used any oil so far, but seeps a bit at the front pan gasket rubber end. I have a filter cutter that I use on airplane filters, required, to inspect the paper media for metal etc, so I'll get a look at that too... Sure would like it to run decent. I have over-sized valves, ported the heads & had them skinned off to clean them up. Also had the block decked to clean up some pits around the coolant passages.
Even when it's not running great, there is a lot of power there to make up for that ! Engine has about 5k miles on it now...
 

pila78

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Well, today the engine just up & died !;) No spark... replaced a few parts, but still no spark:whistle: The new HEI connector W/pigtail didn't want to fit a new Accel dist cap either. Must be some Chinese tolerances in play here... Had it hauled to the shop at the airport, where I can sit back & guestimate the next move ! The harness/wiring to the dist may be a problem. Will likely re-do the IGN + & tach wires...... something simple wrong seems to be the story of my life these days...:thumbdown:
.
 

pila78

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I was right ! It was something simple, that I couldn't see ! The harness in the distributor that connects to the module, has a little ground wire that is grounded to the screw that holds the little capacitor to the casting. That wire had broke..... After-market harness....a real piece of shit of course.

I had a spare SBC distributor, with the MSD module & Accel Super Coil on it, so I just swappped all the parts to the Caddy distributor, which came to life immediately, of course..! So, I put the parts from the Caddy in the spare SBC distributor, repaired the bad wire etc. Gonna check it out on the bench tomorrow to see how it works with the repaired wiring...
 

Darius

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Bill,

I have a hunch that you not only fixed the current total shutoff, but that mysterious intermittent misfire as well.

Seems your coming New Year is on the upswing!!

Best,

bro. d
 

pila78

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Bro d...you may be correct...since the IGN fix, it hasn't missed a beat...So much for after market junk in the distributor.... Maybe the carb got cleaned (twice) for no really good reason, while a bad wire was laying in the bushes, messing with me !
 

Roy Heisenberg

The 472 Crank is stronger due to overlap
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472 Caddy in a ‘75 Jeep J-20 TH-400 Dana-60 100LL
Try adding an extra, new engine to frame ground strap. Sometimes a worn ground strap will get silly when you throw the tranny in gear. Then, pull all the plugs and do the compression check.

Regards, Roy
 

pila78

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Hi Roy ! I added a bunch of extra ground straps, body engine , frame etc when I did the body-off resto. Recently did a comp test too ..It sure has a miss at idle yet though. A friend said the look at plug wires in the dark & see if any sparks are visible ! I swapped/switched a few plug wires to see if one was bad, but didn't see any difference.. Oh well...
 

pila78

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I changed the oil & filter last weekend. Today I got around to inspecting the filter media, and was happy to find no metal particles in the element . ( I have a filter cutter ) It has used about 1.5 qts of oil in around 5000 miles, so at least something is good about this engine ! It's my daily driver, and heater works great !! I have Shell Rotella T6 oil in it since the beginning. The engine idle still has a thump in the exhaust note, which goes away above idle, and seems normal above idle (?) Weird !
 

Roy Heisenberg

The 472 Crank is stronger due to overlap
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So, on another angle, what kind of spark plugs are you running now? Have you tried a fresh set of NGK plugs? My 472 just loves the NGK, and it is a pretty cheap and fun test to just change one thing, and then try to disprove the Null Hypothesis...

I dare you to try NGK,
e-Roy who dances with 472
 

Roy Heisenberg

The 472 Crank is stronger due to overlap
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Yes. That’s the spirit!

Also wanted you to know my secret plug change magic formula.

Buy the NGK plugs, and also buy a new set of wires and a little tube of di-eltric grease.

Here is why.... every time I change plugs, I damage at least one plug wire.

Buy the new plugs, get the new MSD wires, and throw all the old stuff in the trash.

Then, you know the plugs and wires are good!!!




99% of fuel problems are electrical,
Bro. Roy
 

pila78

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All my plug wires are new, Taylor to be exact. I use DC5 grease on plug boots, to keep them in one piece Everything in & on the engine has about 5000 miles since new. The distributor guts were my downfall, for using sub-standard parts. MSD & Accel fixed those problems. What I thought was a miss at idle, may be just the way this cam sounds (?) Anywhere above idle it sounds smooth !. I drive it every day with no complaints since the distributor fiasco, and even gas mile isn't bad !
 

Roy Heisenberg

The 472 Crank is stronger due to overlap
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Coolio ! Good distro guts are the Key! Stay away from the cheap China crap China sucks.
 

pila78

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I've been driving it every day, and I'm quite surprised at how good the gas mileage is ! I've come to the conclusion that my thump at idle may be normal , and isn't a miss at all. !!! Shoulda went with a Comp Cam, so I knew what I had, instead of this one.... oh well...
 

Roy Heisenberg

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Sooooo, how good is the miles per gallon?

Do you get more than 12 MPG ???
 

Darius

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Sooooo, how good is the miles per gallon?

Do you get more than 12 MPG ???[/QUOTE]

Hell Roy, I'm expecting to get about double that!!

What do you get in that Jeep of yours?? (With the engine turned on and pulling the vehicle)

bro. d
 
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