I think I might have an engine problem... :(

-
Buddy had his dart over, was horrible rich, and sounded similar.
Also a big holley.
Im not much of a holley guy,afterwards i learned more.
He was trying to set idle and by dong so opened his transfer ports way up. The more he fiddled the worse it got.
Stubborn, and wouldnt pull carb.
So i had to give up.
Timing was willy-nilly too...
 
Tooljunkie said:
Buddy had his dart over, was horrible rich, and sounded similar.
Also a big holley.
Im not much of a holley guy,afterwards i learned more.
He was trying to set idle and by dong so opened his transfer ports way up. The more he fiddled the worse it got.
Stubborn, and wouldnt pull carb.
So i had to give up.
Timing was willy-nilly too...
Click to expand...
Check fuel pressure also. A new pump could be putting out 10#+. Edelbrocks' only like about 5. I think Holleys can stand a couple #'s more.
 
To big of a carb will run lean. The engine does move enough air to pull fuel through the boosters. I have fun a mighty demon 825 cfm on my 408 and it was happy. Didn’t watch the video, but it just sounds cold blooded. Also when you foul a plug sometimes they just don’t come back.
 
Auto shop 1-0-1. Your engine produces one gallon of water for every gallon of gasoline. The dripping of black water out the tailpipes is a normal cold start issue. You really need to warm up that motor, take it for a long ride. That being said, you may have additional issues.
 
Sounds like a running issue as others said. It's pretty much all been covered - drain the oil into a squeaky clean container, change filter, run the drained oil through a paint filter. Some "stuff" in the oil would be normal but chunks a paint filter will catch are signs of issues. Cut the filter open by hand or using a large cutter that doesn't produce chips. See what's in there. I would change the carb to a known good one. Anything 600cfm and up would do - you're only looking to remove the carb as a problem. Get the engine warmed up. Look up the tuning process. Research. Talk to Brian on some tuning ideas...
 
I think this is one of those case where the Vcan hooked to manifold vacuum could really help. But first you have to make sure the PV is not dumping fuel, due to the low cold-start vacuum.
Say your initial was 16, and the centrifugal was adding 1 degree per 100rpm. Then at 1200 rpm you would have just 18 total, which is woefully inadequate for a cold engine.
Say you could add 10* from The Vcan. That would now be up to 28, and getting somewhere. Your vacuum would jump up, and maybe the PV would stay shut. My 367 likes even more than 28 on a cold start,at say 50* F ambient. So,to those 28,I can add up to 15* with my dash-mounted, electronic dial-back, timing device. By empirical testing I find my engine likes at least 7* more for a grand total of 35*.

I guess this would be a good candidate for a Vcan plumbed directly to manifold vacuum, and I would get the biggest one I could find,22*.You could plumb it thru a thermo-switch, to shut it off as the water temp goes up. Those are available in a multitude of settings and even have some to switch it to ported vacuum as the temp rises .
 
I agree with AJ about possibly needing more timing. When I first bought my car and got it running, the Vcan was connected to ported vacuum and the car didn't run well at start-up (no choke). Even after warm-up, the idle had to be set up over 800-900 just to keep running. When starting, even in warm weather, you had to feather the heck out of the throttle to keep it running until the engine got over 150F or it just wouldn't idle.

Mine had a Demon DP with mech. secondaries on it, that I think is a Speed Demon. It has the choke horn, (no choke flap mounted) so it's either a Road Demon or Speed Demon). It's running good, so I haven't dug into it to identify it.

Anyways,.... First thing I did was hook up a vacuum gauge and adjust the idle mixture screws to find max vacuum. That allowed me to lower the idle adjustment (closing the butterflies) back closer to where they should be. It helped but still wasn't quite right. I gave it a couple more degrees of timing (which helped) then moved Vcan hose from ported to manifold vacuum port.

The extra advance from that made all the difference in the world. Don't get me wrong, it's still a bit rough without a choke at initial startup, but smooths out much sooner and is much more drivable. It will idle at around 650 - 700 now and I no longer smell the heavy gas smell I was smelling when I first got it.

Like AJ said,... make sure you have enough vacuum to ensure the power valve isn't dumping and see if connecting the vacuum advance to manifold vacuum helps...... After you change your oil that is! :p
 
To prove the PV is making that mess, you can replace it with a plug and repeat the test.You can drive it and cruise it,with the plug in there, but you won't be able to use much throttle opening.

If you hook up a vacuum gauge,visible from the drivers seat,this will also allow you to fairly accurately determine the opening vacuum required for the PV, cuz when you roll into the throttle and the carb goes lean, you will feel it and be able to capture the vacuum requirement right there on the dial. Works great if you also have a PV tester, and plumb that same gauge to it.For this test, make sure the powertrain is fully warmed up and the timing has been finalized... and of course the PCV is functioning, the plugs are clean,etc.
 
doogievlg said:
The black stuff on the floor is not a huge deal.

Like others have said I would bet that engine is running rich. Pull the plugs and post pictures. An a/f gauge is always a good investment as well.

If you are getting fuel into the oil then drain it immediately. If there is enough fuel it will ruin your oil and the bearings will smoked...ask me how I know.

View attachment 1715139079
Click to expand...

How do you know???
 
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.
 
MuuMuu101 said:
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.
Click to expand...

I am a bit ignorant on tuning but I don’t believe turning down the fuel pressure will change your a/f mixture. I know on edelbrock carburetors there are two screws in the front to tune that.
 
doogievlg said:
I am a bit ignorant on tuning but I don’t believe turning down the fuel pressure will change your a/f mixture. I know on edelbrock carburetors there are two screws in the front to tune that.
Click to expand...
Pressure won't change the mixture but if the excess pressure is forcing fuel past the needle and seat it then dribbles out of the boosters and into the engine. No way you can tune for that.
 
Thanks guys. Sorry for leaving the thread hanging. I've had no time to even look at the car. I did drive the car 2 weeks ago for about 30 minutes. I gave it a little less gas on start up and the car was very happy while warming up and driving. I didn't touch the fuel pressure or check for anything, yet. I probably won't have time to dig deeper for another two weeks. I'll start it up and drive it today.
 
MuuMuu101 said:
So, it has been getting to operating temperature every time I've driven it.
Click to expand...

But for how long. Just getting it to temp isn't sufficient for the moisture issue. It should come to temp and be driven for a while to dispel any moisture.
 
toolmanmike said:
Pressure won't change the mixture but if the excess pressure is forcing fuel past the needle and seat it then dribbles out of the boosters and into the engine. No way you can tune for that.
Click to expand...

Or even just a piece of string from a fuel line in the needle/seat.
Had that happen myself once on a Holley (not that brand matters :D)
 
Bad Sport said:
But for how long. Just getting it to temp isn't sufficient for the moisture issue. It should come to temp and be driven for a while to dispel any moisture.
Click to expand...

About 5 minutes to warm up and 20-30 minutes of driving. It's usually hanging between 180-200F the entire time.
 
doogievlg said:
I am a bit ignorant on tuning but I don’t believe turning down the fuel pressure will change your a/f mixture. I know on edelbrock carburetors there are two screws in the front to tune that.
Click to expand...

Fuel pressure can certainly change a/f ratio slightly, as can the float levels.
 
MuuMuu101 said:
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.

View attachment 1715138992
Click to expand...



I think I hear a couple things;
* That random noise sounds like a belt(s). Undo your v-belts and see if it's different.
* The constant noise just sounds like normal camshaft / lifter noise that some have (lobe design).
 
You must log in or register to reply here.
-

Back
Top