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#2447247 - 02/05/18 11:11 PM I think I might have an engine problem...
MuuMuu101 Offline
I got lucky at Woodward!

Registered: 12/12/10
Posts: 12255
Loc: Covina, Ca
So, I think I might have a bad engine problem. The engine was built by IMM about two years ago. It's a 408 stroker with forged SCAT internals, ICON pistons, 800 Holley DP, about 10:1 compression, Enginquest heads, 1.6 chromolly rocker arms, all new valve train, etc. Everything in the engine is brand new. To this day, I may have a little over 1000 miles on this engine. Mostly street use with 1 track day and 2 autocrosses.

Essentially since November, I have been driving the Dart once a week for about 10-20 miles a day (20-30 minute drive) and it has been babied. For the first 250 or so miles I wouldn't even go above 4000 rpm. The past two times out (probably 30 miles in total) I may have taken it to 5000-6000 rpms twice in between the two trips. The past two times I've driven the car, I started to notice that the exhaust is coming out a little white on start-up and eventually turns up normal; however, the problem is that now there's a black dust/sludge on the ground from those two days. Ironically, the last time I had the car out, it was actually quite happy and not as rough as usual.

I started it up again today as I've finally had time to do some research on it and the internet is telling me it doesn't seem good (blown headgasket, broken piston, cracked block, etc.). Well, when I started it up today, it sounded like I had a lot more valvetrain noise than usual and some engine knock.



Oil pressure on start-up was 70 psi, but it almost always starts that high. When it warms up and idles, it's usually down to about 25-35 psi. Generally it takes about 5 minutes of running before the engine wants to go. The car consisitently gets 6-10 mpgs despite having a double overdrive (T56) transmission. Around November, the engine was getting some blow-by and the recommendation given to me was to get the carb tuned; however, both IMM and a very well known Mopar Speed shop both tuned the engine last December/January. The second shop didn't change much of anything. Over the past couple months, the blow-by would occur once every 5 start-ups (identified by smoke coming out of the trans tunnel). I checked the oil level today and it's full, granted, the last time I changed the oil was 100 miles after the engine was broken-in (about 1000 miles ago) in January 2017.

Based off of the picture and video, what do you think it is? Is it as bad as I think? Unfortunately, I have literally no time to work on this until maybe mid-June. On top of that, I'm on an extremely tight budget as I've got some major life events coming up.

It sucks that this stuff keeps happening every 3 months, but if anything, I am probably just going to have to wait until June, finish setting up my engine crane and engine stand, and attempt to do an engine diagnostic myself. I'm done with shops.


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#2447250 - 02/05/18 11:22 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
amxautox Offline
Still Retired. Still Posting on Moparts. A Lot.

Registered: 05/13/03
Posts: 96635
Loc: On The Boat, On The Lake, Wa. ...
Looks like a carbon patch on the floor. White smoke should be water/coolant. Next time it smokes white, stick you nose close and sniff it, smell for coolant. Stick your hand in the smoke and feel it between your fingers, then smell your hand.

Do a cylinder pressure test. Take the valve covers off and look for a broken valve spring, bent push rod, broken/bent rocker.
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"Everyone should believe in something; I believe I'll go fishing."

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#2447251 - 02/05/18 11:23 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
DAYCLONA Offline
I Live Here

Registered: 12/10/07
Posts: 15817
Loc: Mass
I'd start by pulling the valve covers, and going thru the valve train, looking at valve installed height, confirming retainer depth, inspect the rockers/shafts/spacers,check the pushrods, set the adjusters/lash, check the lifters, compression test, basically confirm the health of the valvetrain, it'll cost you some time and a set of valve cover gaskets, assuming you have all the tools...then proceed to the carb/ignition

Also maybe consider re-torquing the head bolts prior to a compression tests

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#2447254 - 02/05/18 11:41 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
EV2Bird Online   penguin-006
No more politics

Registered: 06/23/14
Posts: 4015
Loc: Kansas Roads Between 0 and 140...
How warm was the engine when you made that vid? Sounds like a good bit of piston slap and a little odd but much more slap then I get from my street racer with big clearances starting a 10 above which I do every winter.

It also has some odd noises and it looks like the motor bucks a hair with the odd sound.

I would of changed oil sooner but you could still send in a sample and see if its fuel diluted or has coolant in it with little cost.


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#2447262 - 02/05/18 11:58 PM Re: I think I might have an engine problem... [Re: EV2Bird]
MuuMuu101 Offline
I got lucky at Woodward!

Registered: 12/12/10
Posts: 12255
Loc: Covina, Ca
Originally Posted By EV2Bird
How warm was the engine when you made that vid? Sounds like a good bit of piston slap and a little odd but much more slap then I get from my street racer with big clearances starting a 10 above which I do every winter.

It also has some odd noises and it looks like the motor bucks a hair with the odd sound.

I would of changed oil sooner but you could still send in a sample and see if its fuel diluted or has coolant in it with little cost.



That was 2-3 mins after start-up. ~100F?

I haven't heard the valvetrain or "slap" this loud ever since I've had the car.

So, how bad would the problem be if it has coolant in it?
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#2447263 - 02/06/18 12:00 AM Re: I think I might have an engine problem... [Re: amxautox]
MuuMuu101 Offline
I got lucky at Woodward!

Registered: 12/12/10
Posts: 12255
Loc: Covina, Ca
Originally Posted By amxautox
Looks like a carbon patch on the floor. White smoke should be water/coolant. Next time it smokes white, stick you nose close and sniff it, smell for coolant. Stick your hand in the smoke and feel it between your fingers, then smell your hand.

Do a cylinder pressure test. Take the valve covers off and look for a broken valve spring, bent push rod, broken/bent rocker.


I'll check for coolant smell next time I have time to diagnose it. I don't have a cylinder pressure tester, but they seem pretty cheap on Amazon. I think a coworker of mine might have one.
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#2447264 - 02/06/18 12:00 AM Re: I think I might have an engine problem... [Re: MuuMuu101]
Neil Online   content
I Live Here

Registered: 01/19/03
Posts: 12723
Loc: Eagle, Idaho
Remove the spark plugs. They should all look about the same.

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#2447296 - 02/06/18 06:39 AM Re: I think I might have an engine problem... [Re: MuuMuu101]
GoodysGotaCuda Offline
5.7L Hemi, 6spd

Registered: 11/23/04
Posts: 24299
Loc: Texas
I'd take a look under the valve covers and a gander at the plugs, as mentioned. It does sound a bit concerning..it sounds like, whatever it is, is running at crank speed and not cam [1/2] or an individual cylinder speed [1/8].
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#2447301 - 02/06/18 07:07 AM Re: I think I might have an engine problem... [Re: Neil]
BSB67 Offline
master

Registered: 02/19/05
Posts: 3548
Loc: Prospect, PA
Originally Posted By Neil
Remove the spark plugs. They should all look about the same.


This. Start with the simple stuff.

Sounds like a bit of choppy cam and the idle is pretty low. I think I could detect a slight miss. Does not take much to foul plugs. I would go right to changing the plugs first.

Also, it should probably have about 20° initial timing, if you don't already.
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#2447398 - 02/06/18 12:08 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
coronetville Offline
mopar

Registered: 03/23/07
Posts: 477
Loc: Iowa
do a leak down test you can get one cheap from harbor fieght {ya i know, i know,...) you do need a air comp.


Edited by coronetville (02/06/18 12:08 PM)

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#2447403 - 02/06/18 12:15 PM Re: I think I might have an engine problem... [Re: BSB67]
amxautox Offline
Still Retired. Still Posting on Moparts. A Lot.

Registered: 05/13/03
Posts: 96635
Loc: On The Boat, On The Lake, Wa. ...
Originally Posted By BSB67


Also, it should probably have about 20° initial timing, if you don't already.
How do you know what initial timing is required??? You don't have ANY idea what cam is in it.
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#2447448 - 02/06/18 01:39 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
topside Offline
I Live Here

Registered: 01/19/03
Posts: 12428
Loc: So Near, Yet So Far
The dark spots on the floor looks like it's way too rich; does it smell like unburnt fuel when you're behind the car?
I'd say pull the plugs, see if they're dark brown or sooty. Pull the valve covers, look around at oil puddles, pushrods, any metal or coolant being present - expect to see some flakes from valvesprings. Might want to pull the oil filter, cut it open, pull out the media, and see what it's trapped. Expect a little debris on a new engine but shouldn't be much, certainly not a metalflake paste.
A little white smoke on startup isn't necessarily anything but condensation, if it dissipates rather quickly, as in light steam; if it's a cloud that hangs around, that could be coolant, and as AMX says, you'll likely smell it. If you see oil droplets in radiator & coolant droplets on dipstick, it could be from a number of significant things, and an unusually clean spark plug could pinpoint its location.

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#2447453 - 02/06/18 01:51 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
larrymopar360 Online   content
pro stock

Registered: 01/07/11
Posts: 1379
Loc: Central Florida
As topside wrote, see if dipstick looks Milky. I don't see it written anywhere that you have checked that. Sorry if I missed it. Are you losing any coolant? As others mentioned, the black soot on ground doesn't look disturbing to me. Just a little rich at startup when it's choked. White at startup might be fuel mixed with vapor. Hard to tell and can be deceiving.
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#2447470 - 02/06/18 02:22 PM Re: I think I might have an engine problem... [Re: larrymopar360]
Neil Online   content
I Live Here

Registered: 01/19/03
Posts: 12723
Loc: Eagle, Idaho
Put a wrench on the intake bolts. Sometimes they back out on a new engine (along with other bolts) from heat cycles.

My brother had a small block Olds do this and the fiber intake gasket started to break down and slide into the intake port. Car ran poorly until he fixed it.

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#2447493 - 02/06/18 02:57 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
Cab_Burge Online   content
I Win

Registered: 08/23/03
Posts: 31082
Loc: Bend,OR USA
I just listen to your video, I don't hear anything I would be alarmed about shruggy
As far as the condensation and residue on the floor behind the car from it being started and allowed to run in place I wouldn't be alarmed tsk
How old is the gas in the car? The reason I ask that is when cars sit for long periods of time condensation occurs in everything hollow part of the vehicle including the brakes, gas tank, engine, exhaust system and tranny even when stored in a garage shruggy
Letting cars sit for long periods of time is hard on them, way better to drive them regularly long enough to get all the fluids hot enough to evaporate all the condensation out of the engine and drive train twocents Starting them up every 30 to 90 days and letting them run in neutral or park for 10 to 30 minutes is a big NO NO in my book tsk
EDITED. Do the mechanical tests suggested first before doing anything else twocents Compression and leak down both cold and hot as well as look real hard at the spark plugs and let us know your results scope thumbs


Edited by Cab_Burge (02/06/18 08:50 PM)
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#2447745 - 02/06/18 08:38 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
goldduster318 Offline
pro stock

Registered: 01/19/03
Posts: 1422
Loc: Lake Orion, MI
I'd bet the car still runs rich in any time that's not a performance mode. A lot of places won't be good at tuning for this since it usually difficult to do. My experience is that the "rules of thumb" regarding powervalves and jetting are wrong a lot. I went EFI because I could never get it exactly where I want it, and its a lot easier now to get it right. I had to spend a couple days after I got it back from the dyno when the engine was built to have it drive right.

I'll bet the plugs are fouled, the car should get at least 10 MPG. I can beat the crap out of my 340, sit in traffic at the dream cruise, do a lot of short trips, and still get 13 mpg with a 4-speed 3.23's and going 75 mph (3300 rpm) on the freeway, and it only makes maybe 50 less HP than you have and even wider tires. When I had the carb it would get about 11.5 at worst.

If they are forged pistons and its cooler/cold out they will slap a little.
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#2447774 - 02/06/18 09:02 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
Michael Ecks Offline
super stock

Registered: 01/20/03
Posts: 1109
Loc: Columbus, GA
Posting a 15 second youtube clip and getting an internet diagnosis on an engine is about like going to WebMD and typing in "rash". You'll get everything from psoriasis to skin cancer.

What someone hears as piston slap may be nothing more than crap audio from exhaust pulses bouncing around your shop. How tight is the garage spot, what are the walls made of, how close is the exhaust to a wall? Don't answer any of that.

1000 miles on an engine built by someone with IMMs reputation should be barely broken in, not broken. More likely you're having some issues from letting it sit too long. White exhaust could just be condensation cooking off the inside of the pipes, a little smoke in the trans tunnel could be oil or ATF drips cooking off the outside of a pipe. The grey spots just look like a rich idle to me, same thing my car did all the time until I got it tuned right, and that same condensation inside the pipes will carry carbon out of the pipes along with it. I'll bet if you start it up and watch in a couple of minutes you'll actually have little black puddles underneath the pipes that dry up eventually and leave the carbon that was floating in it as dust. Valve train noise could just be that the lifters bled down and need some time with oil pressure to pump back up.

As Cab_Burge said just cranking it every couple of months and letting it idle isn't good for a car. If your carb doesn't have a four corner idle and you are only warming it up, then you could have had a bad gas situation in the secondary side gumming up the jets or needle and seat, since no new gas is flowing through. Happened to me personally doing the just idle warm ups over the course of 6 months or so.

You have good oil pressure and you said it drove fine the last time you took it out. If it was mine, first thing I would do is take it out for a longer drive to get fluids circulating everywhere and get the fluids hot enough to burn off any condensation. If that doesn't clear everything up then its time to start taking things apart. Check plugs for fouling, check oil for metal flecks, pull the carb bowls to look for crud, pop the valve covers and check lash/preload.
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#2447786 - 02/06/18 09:12 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
EV2Bird Online   penguin-006
No more politics

Registered: 06/23/14
Posts: 4015
Loc: Kansas Roads Between 0 and 140...
Clearly not everyone is as smart as this guy....

https://www.youtube.com/watch?v=Pn-sNkeW7uA

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#2447789 - 02/06/18 09:15 PM Re: I think I might have an engine problem... [Re: Michael Ecks]
BSB67 Offline
master

Registered: 02/19/05
Posts: 3548
Loc: Prospect, PA
Originally Posted By Michael Ecks


1000 miles on an engine built by someone with IMMs reputation should be barely broken in, not broken.


Exactly. Why would you start with the motor's bad?
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#2447798 - 02/06/18 09:33 PM Re: I think I might have an engine problem... [Re: amxautox]
BSB67 Offline
master

Registered: 02/19/05
Posts: 3548
Loc: Prospect, PA
Originally Posted By amxautox
Originally Posted By BSB67


Also, it should probably have about 20° initial timing, if you don't already.
How do you know what initial timing is required??? You don't have ANY idea what cam is in it.


Just using my ears. It's a good size cam for a street car. It will like more initial than less, IMO.

So I based on what you said he should not look at the idle tune and plugs, but first look for broken valve springs and bent pushrods. Then what, pull the motor?


Edited by BSB67 (02/06/18 09:41 PM)
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#2447801 - 02/06/18 09:41 PM Re: I think I might have an engine problem... [Re: BSB67]
amxautox Offline
Still Retired. Still Posting on Moparts. A Lot.

Registered: 05/13/03
Posts: 96635
Loc: On The Boat, On The Lake, Wa. ...
Yup. lol
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"Everyone should believe in something; I believe I'll go fishing."

-Henry David Thoreau

Men and fish are alike. They both get into trouble when they open their mouths

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#2447822 - 02/06/18 10:43 PM Re: I think I might have an engine problem... [Re: EV2Bird]
Cab_Burge Online   content
I Win

Registered: 08/23/03
Posts: 31082
Loc: Bend,OR USA
Originally Posted By EV2Bird
Clearly not everyone is as smart as this guy....

https://www.youtube.com/watch?v=Pn-sNkeW7uA

I'm sure both of his parents owned and drove Chevy as well as smoke the old good stuff whistling grin
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#2448083 - 02/07/18 02:07 PM Re: I think I might have an engine problem... [Re: Cab_Burge]
RoadRunnerLuva Offline
master

Registered: 01/31/03
Posts: 2798
Loc: Ball of Confusion
What (if anything) did Brian at IMM say about your engine dilema?
You said you took it back to him to have it tuned? HE built it...
what was HIS advise to you? You also said you were done with shops...
I am assuming he was of no help to you? work
And BTW his reputation isn't all it's cracked up to be, I have dealt
with him in the past myself as a customer, and it didn't end well. twocents
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#2448119 - 02/07/18 03:03 PM Re: I think I might have an engine problem... [Re: EV2Bird]
madscientist Offline


Registered: 09/17/14
Posts: 2134
Loc: Washington
Originally Posted By EV2Bird
Clearly not everyone is as smart as this guy....

https://www.youtube.com/watch?v=Pn-sNkeW7uA



That dude is weird. He has a face I just can't trust. And the engine was rebuilt by HIM.
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#2448219 - 02/07/18 06:54 PM Re: I think I might have an engine problem... [Re: EV2Bird]
larrymopar360 Online   content
pro stock

Registered: 01/07/11
Posts: 1379
Loc: Central Florida
Originally Posted By EV2Bird
Clearly not everyone is as smart as this guy....

https://www.youtube.com/watch?v=Pn-sNkeW7uA
That was a really annoying and waste of 2 minutes 4 seconds.
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#2448285 - 02/07/18 09:45 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
MuuMuu101 Offline
I got lucky at Woodward!

Registered: 12/12/10
Posts: 12255
Loc: Covina, Ca
For the record, I wasn't expecting/blaming IMM for building me a broken motor. If it is broken, I probably would have assumed it was my fault anyway. IIRC, IMM set initial timing to about 34 degrees. Unfortunately, Brian forgot to give me cam specs and they seem to be lost. I just know it's something like a 238/242.

Since November, I have been driving the car every weekend. Generally I let the car warm-up for 5-10 minutes and then I go for about a 15-20 minute ride. Generally, when I've been driving, the engine runs between 180-200F for the water temp. So, it has been getting to operating temperature every time I've driven it.

As for the rest, thank you for the advice. I think I'm going to start simple and pull the spark plugs and inspect them whenever I get free time. While I'm at it, I'll change the oil (as it needs it anyway).

When the car was first built, the person who put it together set the fuel pressure to about 8 psi. At my first autocross, I ended up flooding the carb on the first turn 3/4 runs. After that incident I turned the fuel pressure down to 6.5 psi as the youtube video on tuning Holley carbs I watched said 7 psi MAX. I think I may bump it down a little more (5 psi-ish) as, like you're all saying, it seems like its running a little too rich.

I think I'll take it on longer runs on the weekend to the gf's house which is 30 miles one way and generally a 30-40 minute drive.
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#2448298 - 02/07/18 10:10 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
GoodysGotaCuda Offline
5.7L Hemi, 6spd

Registered: 11/23/04
Posts: 24299
Loc: Texas
Originally Posted By MuuMuu101

When the car was first built, the person who put it together set the fuel pressure to about 8 psi. At my first autocross, I ended up flooding the carb on the first turn 3/4 runs. After that incident I turned the fuel pressure down to 6.5 psi as the youtube video on tuning Holley carbs I watched said 7 psi MAX. I think I may bump it down a little more (5 psi-ish) as, like you're all saying, it seems like its running a little too rich.



Adjusting fuel pressure is not the way to lean out a tune. Too much pressure can push fuel past the floats and through the jets. Once you are below that threshold [7psi], you need to be adjusting idle mixture screws and jetting.
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#2448301 - 02/07/18 10:18 PM Re: I think I might have an engine problem... [Re: GoodysGotaCuda]
MuuMuu101 Offline
I got lucky at Woodward!

Registered: 12/12/10
Posts: 12255
Loc: Covina, Ca
Originally Posted By GoodysGotaCuda
Originally Posted By MuuMuu101

When the car was first built, the person who put it together set the fuel pressure to about 8 psi. At my first autocross, I ended up flooding the carb on the first turn 3/4 runs. After that incident I turned the fuel pressure down to 6.5 psi as the youtube video on tuning Holley carbs I watched said 7 psi MAX. I think I may bump it down a little more (5 psi-ish) as, like you're all saying, it seems like its running a little too rich.



Adjusting fuel pressure is not the way to lean out a tune. Too much pressure can push fuel past the floats and through the jets. Once you are below that threshold [7psi], you need to be adjusting idle mixture screws and jetting.


Coolio. I'll watch some youtube videos from Holley to adjust idle mixture screws and jets.
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#2448488 - 02/08/18 10:42 AM Re: I think I might have an engine problem... [Re: MuuMuu101]
krautrock Online   content
top fuel

Registered: 01/27/03
Posts: 1735
Loc: central texas
Originally Posted By MuuMuu101
Originally Posted By GoodysGotaCuda
Originally Posted By MuuMuu101

When the car was first built, the person who put it together set the fuel pressure to about 8 psi. At my first autocross, I ended up flooding the carb on the first turn 3/4 runs. After that incident I turned the fuel pressure down to 6.5 psi as the youtube video on tuning Holley carbs I watched said 7 psi MAX. I think I may bump it down a little more (5 psi-ish) as, like you're all saying, it seems like its running a little too rich.



Adjusting fuel pressure is not the way to lean out a tune. Too much pressure can push fuel past the floats and through the jets. Once you are below that threshold [7psi], you need to be adjusting idle mixture screws and jetting.


Coolio. I'll watch some youtube videos from Holley to adjust idle mixture screws and jets.


first thing i would do is pull the plugs and see if they are black.

and also set your float level, mid way up the glass if it has that in the bowls, if it's just a screw, the fuel should be right at the bottom if you pull the screw out, engine idling when you check this...

proper idle mix tune won't have the car idling well until it warms up some. tune the idle mix after the motor is completely warm.
go around the carb (all four idle screws) screwing them in 1/8th turn (leaner) until the idle stops getting higher and smoother, then maybe richen it up just a touch from there, like 1/16th of a turn on all screws...
you can also tune the idle mix for highest vacuum reading instead of RPM.

if your plugs are real black.
for the jetting, lean it out in small steps. drive down the hwy steady cruise, maybe 2000rpm, once you are too lean you will feel some very subtle surging. from there jet it back up two sizes maybe.
because of the power valve in the primary side, the seconday jets will be larger by something like 8 sizes or so. (look up the baseline tune for your carb).

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#2448520 - 02/08/18 11:41 AM Re: I think I might have an engine problem... [Re: MuuMuu101]
amxautox Offline
Still Retired. Still Posting on Moparts. A Lot.

Registered: 05/13/03
Posts: 96635
Loc: On The Boat, On The Lake, Wa. ...
And check to see if the power valve is blown.
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"Everyone should believe in something; I believe I'll go fishing."

-Henry David Thoreau

Men and fish are alike. They both get into trouble when they open their mouths

author unknown


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#2448641 - 02/08/18 03:43 PM Re: I think I might have an engine problem... [Re: MuuMuu101]
dynorad Offline
mopar

Registered: 01/20/03
Posts: 512
Loc: Niwot, CO Formerly denn...
I'd rejet sooner rather than later. Fuel washdown of the cylinder walls can destroy your ring seal.
Another option would be having it dyno tuned.

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#2449954 - 02/11/18 01:30 AM Re: I think I might have an engine problem... [Re: MuuMuu101]
slantzilla Offline
I Live Here

Registered: 01/24/03
Posts: 18151
Loc: Park Forest, IL
The white smoke and the black soot can be as simple as it is pig rich. Rich can cause condensation in the exhaust if it is not driven a lot and burned out. The black soot is just the water washing the carbon out of the pipes.
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