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

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MuuMuu101

MuuMuu101

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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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With the plug wires shaking like in the video, I would check the plugs for being loose. The video is not very good.
 
That bit of soot in the picture looks fairly normal to me, especially if the car has been parked a while and run once or twice without warming up enough to burn moisture out of the exhaust.

That has happened to me becore when my cars are parked without running for a few weeks or months over the winter.

I havent had a chance to watch the video.
 
It sounds to me like all eight are making the noise......sounds like a diesel. This is usually a few things. First, it could be perfectly normal if it has floating wrist pins. They are known to make a little noise sometimes. Secondly, if it goes away or lessens significantly when warmed up, that's indicative of normal forged piston expansion......if so equipped. So it's possible the noise is normal. I have heard lots of engines do it, including some I have built myself.
 
I agree the video ain't that good. Black is partially burned fuel.

Sounds like you may have a bad exhaust rocker. That's my guess from the video.

What carb is it?
 
Like SG said, don’t get the cart ahead of the horse... the shake of the motor isn’t normal in my eyes either, but the soot could be something simple. start small, little stuff like checking to see if all the header tubes are hot, (dead plug) or looking for a bad plug wire, slipped distributor, loose converter bolt hitting (knock), crap gas... I’ve had all sorts of stuff make me think I had a massive problem... start slow, spark, fuel, timing, compression check. Pull the valve covers and watch it turn over... does everything open and close?

Hopefully you can track it down without pulling the pig apart if it doesn’t need it. And I hope it doesn’t!

Joe
 
RustyRatRod said:
It sounds to me like all eight are making the noise......sounds like a diesel. This is usually a few things. First, it could be perfectly normal if it has floating wrist pins. They are known to make a little noise sometimes. Secondly, if it goes away or lessens significantly when warmed up, that's indicative of normal forged piston expansion......if so equipped. So it's possible the noise is normal. I have heard lots of engines do it, including some I have built myself.
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Normally, when it warms up it runs better and yes it has forged pistons. I just didn't feel comfortable getting it to operating temperature. It also tends to smell like gasoline quite a bit.

yellow rose said:
I agree the video ain't that good. Black is partially burned fuel.

Sounds like you may have a bad exhaust rocker. That's my guess from the video.

What carb is it?
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It's not that good of a video, but I just wanted to capture something quick. I'll get my valve covers off sometime between now and June.

joeboy said:
Like SG said, don’t get the cart ahead of the horse... the shake of the motor isn’t normal in my eyes either, but the soot could be something simple. start small, little stuff like checking to see if all the header tubes are hot, (dead plug) or looking for a bad plug wire, slipped distributor, loose converter bolt hitting (knock), crap gas... I’ve had all sorts of stuff make me think I had a massive problem... start slow, spark, fuel, timing, compression check. Pull the valve covers and watch it turn over... does everything open and close?

Hopefully you can track it down without pulling the pig apart if it doesn’t need it. And I hope it doesn’t!

Joe
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Thanks Joel,

Sometimes I get a little ahead of myself. I just get tired of the things that pop up every couple months or so, but that comes with the old car territory, I guess. I'll check some of the things you've mentioned (or learn how). Try to keep it simple, like you said.
 
AJ/FormS said:
Sounds like a big cold rich engine to me, trying to flood itself to death,lol.
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Also a possibility. The car always smells like gasoline on start-up and runs rough. I've been wanting to put a Fitech on this car for forever just so I can turn the key and go. Just haven't had time to pull the trigger myself.

I'm feeling a little more relieved that this could very well be a much smaller issue than I originally imagined.
 
It wouldn't hurt to invest in an IR temp gun. Once you have one, you'll find a million uses for one of them.

For example, I keep mine by the bed and check my wife to see how warm she is.


Then I go sleep in the spare bedroom. Makes me laugh every time.
 
AJ/FormS said:
Was that video in fact with a cold engine?
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Yes. It was running no more than a couple minutes and when I looked at the water temp gauge before shutting the car down, the needle never left 100F.

It usually takes about 5-10 minutes before the water temp reaches 130-150F. When it's running it never deviates from 180-200F, whether in traffic or on the track.
 
The soot on the floor is normal at this time of year. Especially if the choke is not set right, or, if no choke, you have to babysit the engine with numerous throttle blips. What can happen is the extra fuel and soot condenses in the cold mufflers, and the throttle-blips pick it up and blow it out the back. This mixture forms hydrochloric acid in your muffler and will rot it out. I drill a 1/8 hole in the lowest part of the muffler and let it leak out. Yeah it makes a mess, but my Dynomaxers are 18 years old and counting.
The white smoke may also be normal,especially if the humidity is high.Water and energy are the normal products of the internal combustion engine. As the exhaust system heats up, the moisture turns from visible to invisible. It's still there you just can't see it. Some may condense at the end of the pipe as it hits the cold atmosphere and you'll see it dripping there. On some cars the moisture condenses back into water inside the last foot of pipe, and when you see them take off, they leave a trail of water. If you are concerned, a pressure test should find a bad headgasket.
Cold atmosphere means cold relative to the heat in the exhaust gasses, not relative to what the thermometer is saying. You gotta remember, the gasses are leaving the chamber at maybe 550 or more, at idle.
I think I would consider driving away a little sooner. If she don't like it, give her more timing. You do have a Vcan hooked up right? lol. This is the time she wants those extra 15/20*.
 
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yellow rose said:
It wouldn't hurt to invest in an IR temp gun. Once you have one, you'll find a million uses for one of them.

For example, I keep mine by the bed and check my wife to see how warm she is.
Then I go sleep in the spare bedroom. Makes me laugh every time.
Click to expand...

Yer makin that up. My old doll is so hot I can't spend moreN a coupla minutes with her, then I'm off to my bed.
 
An 800 double pumper does sound good in theory but if you are just cruising around you may be too rich.If you smell gas at idle you are wasting gas in a street car.Try to find a friend with a smaller carb to test with and get it to temp before checking for issues.As stated that's condensation mixed with soot from too much fuel over time coming out of the exhaust.
 
if it smells like fuel, it could be over rich jetting, too high float level, bad choke setting, etc, but it can also be poor combustion from electrical secondary misfire or both together. I agree with suggestion to start with basics, like adjust valves, check float level(s), inspect plugs and plug wires, confirm rotor phasing, check compression, vacuum tests. If problems are indicated, you may need a leak down test to narrow it down.
 
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, -LOL-way too large. 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.-<<These are HARD on an engine, how good is your oil control?

Also what is the camshaft? Just curious. I'm also assuming the engine wasn't on Brian's dyno, was it?

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. <<Completely normal. Ironically, the last time I had the car out, it was actually quite happy and not as rough as usual. <<What does this mean? Poor cam selection vs expectations? Or poor tune? I'm betting on the latter.

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. I don't understand how an engine GETS blowby once every 5 start-ups. Either it has a significant amount of blowby or it doesn't.

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...


The video doesn't sound good but that doesn't mean much. Brian knows how to set up piston to cylinder wall clearance so I doubt its anything to do with that. Beg, borrow or steal a much smaller carb-preferably a V.S. , map out your timing, cranking comp test, fresh plugs, fresh fuel and document everything. Change your oil and filter through a paint strainer into a clean container, cut open oil filter as well--actually do this before anything else-if all looks good fill with new oil and proceed to diagnose. Have fun--this is part of the old car culture and I consider it a rite of passage otherwise go get a new Challenger or Hellcat variant and never look back. J.Rob
 
I've never claimed to be a motor expert, but I'm hearing a couple things that are concerning me. I agree that it sounds like it is running rich, possibly very rich. Have you had the plugs out of it? Do they look like it has been running rich?

My concern is that it is making more noise as time goes on. I would pull the dipstick and see if it smells like gas. Like I said, I am by no means a motor expert, but I have heard of cars running WAY rich actually washing the cylinder walls. You've stated that you are getting excessive blow by when it is cold. I would check to make sure you aren't getting raw gas blowing by and diluting your oil. Might explain why the noises are getting worse as time goes on since your last oil change. I have heard of instances of where that got so bad that they hurt their motor.

If that is it, I would think you would want to get the oil changed and adjust the carb to stop it early before it does any damage. Correct me if I'm wrong, but don't rich running engines run cooler? Might explain the lower operating temps too.
 
AJ/FormS said:
Sounds like a big cold rich engine to me, trying to flood itself to death,lol.
Click to expand...
Yup. Not trying to hijack but my 408 did a very similar thing last Saturday. Ran very rough at start up (manual choke) and kept loading up and dying. It always runs rich at idle and has to be babied until warmed up (it was 47 degrees F). I have a couple of plugs that come and go and a buddy noticed that one was back feeding up the spark plug wire and jumping over to the next wire. Pulled a couple plugs and they looked very sooty for having 500 miles on them. A fresh set of plugs and $25 worth of non ethanol premium fuel made all the difference in the world.
 
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.

05CF7B77-A498-4DDD-816A-C62C81309AF9.jpeg
 
Sounds like a loosely built engine running 0W20 oil.
What oil are you using?
 
Spark plugs that are too cold can aggravate the rich running issue also. I know there isn't a heat range for strokers but a warmer plug might help. I had that issue with my 273.
 
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