Running bad & lean

Red98422

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Don’t give up in the Cadillac man!! All this wrenching and frustration is just right now, the feeling you get after a finally completed repair is truly one of a kind.

Have you done spark check yet on the plugs themselves? I’ve found brand new plugs that scatter spark.
Double/triple check the firing order?
Resistance check on the plug wires?
 

Cad Man

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Vacuum leak is not intermittent.. atleast not on the intake gasket..

unless it's a broken hose or something stupid like that Are you sure this is a ignition problem Bill ?

If it's not running out of fuel from bad pump vapor lock or plugged filter ..well you know where I'm going
..

It sounds to me as if you've done just about everything but pull that qjet..
Almost all your symptoms appear to be from excessively lean. Lean is how jets are unless you go inside and start drilling and changing parts. A tiny bit of dirt floating around inside that carb may intermittently block a jet. It may be somewhere you cant see inside a passage

If its carb related..How about trying the carb off your other car ??

The lack of power has been no doubt the cam. And to some extent the carb ..
 
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pila78

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You are correct broD! Must have been something I had for lunch !:) Anyway, today I did a compression test on cyls 2,4,6, and 8, removed the rocker cover & inspected everything that was visible. It all looks fine. The comp test showed those 4 to be within less than 5 lbs of each other, around 130 ( according to my cheap gauge) The engine does have a miss at idle, which is hard to nail down. Got to thinking today, about the exhaust having an H pipe, and that maybe what I hear in the exhaust note, is actually from the right ( passenger) side) I'll be pulling the plugs & do a comp test on that side next, along with pulling the rocker/valve cover for inspection. The plugs on the left side look fine, about the right color etc Interesting thing today: while fooling with the plug wires while it was running, I got zapped a bit, and a spark jumped from my leg to the fender I was leaning on !!:D
I was also thinking about the vacuum piston on the carb primary needles, possibly sticking, causing the off idle jerking, backfiring etc....I'll have to get into that car again & see if it's a possibility....

Bro Bill !:)
 

pila78

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My boat, a 26 ft Mahogany cabin cruiser, has a Holley Q-jet replacement carb on it. ( Chevy engine) I believe it would bolt on my manifold OK. I may just try it & see what it does !
 

pila78

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I can get a Q-jet carb for a '76 Eldorado, but not sure if it will be a bolt on, to try it out...17056530...mine is a 6230.. Modifying my carb was probably a bad idea ! It likely would have worked OK in stock configuration.
I'm wondering if something is in one of the passages in it, floating around & intermittently causing the problem I have (?) I took it apart & blew out all the passages etc, but ??
Maybe I need to buy a horse ? One horse power that would be dependable !
 
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Darius

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[QUOTE="peter dennis, post: 200774, member: 4856" ]The major problem with those one horsepower things is that the steering and brakes don't always work as you would expect.[/QUOTE]

Not to mention the exhaust!!!

bro. d
 

pila78

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Tomorrow, Monday, I'm gonna remove the carb & check the intake manifold passages. Today when I drove it, it acted up, with the usual sputtering etc, but I noticed that if I slipped it into neutral & revved it a bit, it would smooth out...(?) Almost acts like something is in one of the passages, moving around ! Sounds crazy, but so am I at this point !-
 

pila78

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When my motivation and energy level comes up, I'm gonna remove the right side valve/rocker cover & see if anything looks wrong in there, & do a comp test etc.. Since it revs up over 4k without a load, the fuel must be getting to the carb OK Fuel pressure gauge sez 5 PSI......don't
see a fuel problem at this point..
 

pila78

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Today I removed the right side rocker cover ( all looks normal ) checked plugs did comp test etc. Nothing has changed in the way it runs. All the spark plugs look great. There is only around 3500 miles on the this engine, by the way..

Next is looking at the power piston that moves the primary metering rods. Kinda seems like that piston doesn't always let the rods come up with low vacuum when throttle is increased..
It seems that when I open the throttle far enough, the low vacuum lets that piston come up ...that sound reasonable ??
So what about that spring ? Are there selections of those ? I just looked & can't find the ones I had.... The one that's in there may be fine, and it's just the piston that is fucked up & not always moving with the spring
Tomorrow I'll find out more when I get back into the carb...
 

gary kosier

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Last time I went up to Cliff Ruggles' place, I got a selection of power piston springs. I think it was four different springs.
I'd recommend you get a set. Also,with the motor NOT running, reach down the vent tube and make sure the piston is free and
springs back up after you push it down.

Gary Kosier
 

pila78

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I checked the power piston, like Gary suggested, and it's free, with no binding. My other thought is that there may be something in the vacuum passage that works that piston. Anyway, I'll pull the carb again & check the vac passage to that piston well... Like I said earlier, if it bucks & acts up, I put it in neutral & rev it a bit, and it runs better for a bit, which is why I suspect a vac blockage to the power piston well....
 

Darius

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I checked the power piston, like Gary suggested, and it's free, with no binding. My other thought is that there may be something in the vacuum passage that works that piston. Anyway, I'll pull the carb again & check the vac passage to that piston well... Like I said earlier, if it bucks & acts up, I put it in neutral & rev it a bit, and it runs better for a bit, which is why I suspect a vac blockage to the power piston well....
Not that what I'm about to share helps your situation one little bit …. but we've got a 1990 Honda Accord that is doing the same thing, bucking and snorting. Took it to one shop and they said it was "oil in the distributor" and would cost $500. Well, that didn't make a lick of sense to me (but what the hell do I know about Japanese cars) so I took it to the Honda Dealer who quickly diagnosed it as "oil in the distributor" which they would be happy to replace/repair for $700.00!!!!!

I thanked them for their time, took the car home and looked up, "All you ever wanted to know about changing out a 1990 Honda Accord distributor" on YOU TUBE (I am trainable)!!
I ordered the 'up graded' version of the ailing part from RockAuto. With shipping the total came to $102. Being the arrogant beggar that I am, I told my son and wife that I'd swap out the old and put in the new - and have it running in 43 minutes … including laying out my tools. Silly, boastful me.

The process actually took 48 minutes -- including several "My damned back is killing me" breaks.

Now, the car still bucks and snorts ….. but I saved a bunch of money, to get to the same place, by doing it myself. Image how pissed I would be had I paid one of those others big money to have no better results.

Screw it,
bro. d
 

kzhurley

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I checked the power piston, like Gary suggested, and it's free, with no binding. My other thought is that there may be something in the vacuum passage that works that piston. Anyway, I'll pull the carb again & check the vac passage to that piston well... Like I said earlier, if it bucks & acts up, I put it in neutral & rev it a bit, and it runs better for a bit, which is why I suspect a vac blockage to the power piston well....
From what I remember.. Lol..

When I was working at getting my qjet tuned, I dropped a drinking straw down the vent tube and was able to make sure that power piston moved by cracking the throttle.. I should be down at high vacuum and it will lift when you hit the throttle quick.
 

mario

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"but I saved a bunch of money, to get to the same place, by doing it myself. Image how pissed I would be had I paid one of those others big money to have no better results."

Bro d:
After what I went through with my wife's gmc...I feel your pain. 5 Saturdays wasted, but I got a new radiator cap, etc, etc, etc...:confused::cautious::mad:
 

pila78

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Years ago, I bought a new 1971 Datsun pickup...4 cylinder powerhouse ! It ran great all the time I owned it, about 3 years. I had traded in a '63 Caddy, a 62 Coupe ( No Deville !) Manual windows etc It was a good car...don't remember the engine size.......390 ?
At least the El Camino runs, even if it acts up. My Buick Park Avenue Ultra is in the side yard. Electronic problems, cam & crank sensors etc It decided not to run,..........again..

Sorry for drifting way off of the thread !
 

peter phillips

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Bill ,earlier in this thread you mentioned a spark jumped from your leg to the fender .Did you pursue that ? Bad plug wires can cause all sorts of nasty intermittent problems and sparks jumping off your leg is just not normal .I'd pull the wires and put an ohmmeter to them ,a lead on each end .I'd also twist the wire around to see if continuity comes and goes while you do it .Another thing you might try is running the engine in the dark and looking for errant sparks .
A good and proper set of plug wires should not leak any sparks .
 

pila78

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Hi Peter...no, I was using long insulated pliers, to pull plug wires off of the plugs, and got zapped right through the insulation on the pliers !! Nothing on this engine has more than around P1010990.JPG 4000 miles on it, except carb & distributor. The AC pump is a Chevy part, just for the belt & not hooked up.
 
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