Diagnosing a misfire

[Mrturner1]

Originally Posted by 1969c10joe

mr turner your thread is very interesting to say the least. did you determine the problem with leak down test and or compression test?Hows your valve guides?

My threads do typically end up that way haha

I didn't do the leak down or compression tests today. I've had a feeling that the rings were bad for a while now, and wet oil all over the plugs is proof enough for me. I've been plotting a very low compression turbo build for months now and just needed a reason that would justify starting it, and it appears I have the reason now. I'm thinking that Davepl is on to something though and this first self built short block needs to be real cheap, because if/when I make a mistake I don't want to ruin a 2000 dollar Dart block and some nice AFR heads.

[1969c10joe]

circle track guys always know a shop who provides bulletproof bottom ends cheap those engines are tough to break just another idea

[Mrturner1]

Originally Posted by 1969c10joe

circle track guys always know a shop who provides bulletproof bottom ends cheap those engines are tough to break just another idea

That's a great idea actually. I'm new to this town so I don't know anyone but there is a circle track about 45 minutes away. Suppose I could go and ask some questions. I may just build one myself though, and see how it goes since it's my first short block

[Grumpy old man]

Buy a crate 383 and weld the hood shut ! Then concentrate on your frame , brakes and suspension .

[Mrturner1]

I was thinkin last night, and during the whole process from the very beginning when I just wanted to identify what cam I had, all the way til now I never really slowed down and made a plan, and took the time to do it all right. It's very very fast, and under the hood looks great with fresh paint and lots of shiney stuff, but it was bound to keep having issues and make me unsatisfied with the outcome after a lot of hard work and money invested. I think I'm gonna take this opportunity to really go through the whole process and draw up a plan, and then start/finish one chunk at a time and really do it right. I'll make a plan for suspension and brakes, then rear diff and trans which don't need much now, learn how to do body and paint plus a little interior work like a nice new seat and dash, and then build a nice cheap short block to put all my go fast parts on and finish it with a new wiring harness that has no splices or loose ends, just nice and clean and all soldered and shrink tubed. This is a real bummer but I'm pretty excited to see what the end result will look like.

[Mrturner1]

Originally Posted by Grumpy old man

Buy a crate 383 and weld the hood shut ! Then concentrate on your frame , brakes and suspension .

That would be fun too. It's certainly an option, but it would also be fun to put together a short block on my own

[Grumpy old man]

Investing money into any project be it a truck or a house the first thing you start with is a solid foundation , in this case a clean finished frame and suspension BEFORE you add go fast shiny parts . It's how it's supposed to be done , in today's instant gratification world it's seldom the case . How many times do you see in here daily someone bolt thousands of dollars of airbag suspension or 500 + HP to a drum brake rusty frame ? Just for outward appearances ? I've spent 3 years working on my restomod searching for the "right" parts it's been at considerable time and expense but in the end worth every dollar and hour I'll put in it . Choose your build plans carefully and use proven processes to get it to come to your end goal ! If anyone can just toss thousands of dollars into the wind good for them . I can't when I'm done I have to end up with a professional quality product with a value equal too or better than my investment of time and cash . Matt , you can't tell me you wouldn't be way further ahead in cash and time if you had not bothered with this welded , cracked short block and so so heads that's lasted less than a year than if you had started with a solid foundation and a crate 383 ? You've got a year in an engine that's toast . Professionally built engines don't turn 7,000 rpms weekly for long let alone every trip out the driveway and free revving an engine over 5,000 in the driveway will speed up the end fast . Old guys do certain things for a reason we've learned our lessons many years ago ... Take advantage of our past learning experiences and save yourself the costly education of being self taught !

[Mrturner1]

Originally Posted by Grumpy old man

Investing money into any project be it a truck or a house the first thing you start with is a solid foundation , in this case a clean finished frame and suspension BEFORE you add go fast shiny parts . It's how it's supposed to be done , in today's instant gratification world it's seldom the case . How many times do you see in here daily someone bolt thousands of dollars of airbag suspension to a drum brake rusty frame ? Just for outward appearances ? I've spent 3 years working on my restomod searching for the "right" parts it's been at considerable time and expense but in the end worth every dollar and hour I'll put in it . Choose your build plans carefully and use proven processes to get it to come to your end goal ! If anyone can just toss thousands of dollars into the wind good for them . I can't when I'm done I have to end up with a professional quality product with a value equal too or better than my investment of time and cash . Matt , you can't tell me you wouldn't be way further ahead in cash and time if you had not bothered with this welded , cracked short block and so so heads that's lasted less than a year than if you had started with a solid foundation and a crate 383 ? You've got a year in an engine that's toast .

Yeah, I probably only got about 8 hours total of driving time realistically. And some of that was bein pulled over on the side of the road broke down. If bet I'm into it for 3000 bucks so far, which is only 800 shy of a 430 hp Blueprint 383 long block lesson learned, this time I'll do it right. I don't have a plan drawn up yet, but I do have an end date that id like to accomplish, because my dream is to drive this truck (AFTER I get a gear vendor over/underdrive of course) way out there and cruise along in the 2017 power your. It's a big commitment and won't be easy, but I'd really love to do it. If I build it right there's no reason it can't make it reliably.

[Grumpy old man]

Look at how much time and cash I have into a few trucks and i haven't driven any of them 1 inch or 1 minute in years ��

My suggestion to you is sell the long bed truck right now as it is and find a v8 manual 67 short bed to build ...

[Mrturner1]

Originally Posted by Grumpy old man

Look at how much time and cash I have into a few trucks and i haven't driven any of them 1 inch or 1 minute in years ��

My suggestion to you is sell the long bed truck right now as it is and find a v8 manual 67 short bed to build ...

And leave all my parts on it you mean? There's an awful lot of money under the hood just in topend parts. The carb and intake is brand new, probably 1000 bucks there. Almost brand new cam and valve train, probably 1000 bucks there. 600 dollar stall converter and about 1000 bucks in Autometer gauges and B&M floor shifter. I'm not being condescending I'm just makin sure you have the facts, because it would be a big move. A 67 short with a stick sounds like it would be very fun, and a little more geared towards what I use the truck for.

If the rings weren't goin and I slapped a coat of paint on my long bed if be able to get a big chunk of change for it. I've seen lesser long beds goin for 8k around here, mostly stock but with a paint job.

[Mrturner1]

Like this one, 3000 bucks and there's nothin special about it at all.

http://sacramento.craigslist.org/cto/5776700835.html

[Grumpy old man]

You have no idea the rings are going the plug picture I saw was fuel not oil . Add everything you have in it and add an additional $1,500.00 and dump it . Find a 67 or a 72 short bed and build it from there ( middle year model classics don't bring as much as 1st year models and last year models ) (as a family investment , not a drag strip toy ) you have a young wife and kids , you can't afford a drag strip toy . Ask me how I know ! Every dollar you spend spinning wheels for fun takes dollars away from your family . And no your no entitled to take money away from your kids for your entertainment you already had that the day they were conceived ,they always need more no matter who you are or how much $ you have .

Everyone says they'll never sell their truck but they all get sold someday and you should plan for it from day 1 .how many owners did yours have before you ? Sell it as it sits !

[1969c10joe]

WELD THE HOOD SHUT thanks grumpy that made me laugh yeah im not convinced your rings are going im using cell phone hard to see

[1969c10joe]

mr turner I humbly suggest doing compression and leak down test. burning oil produces bluish smoke burning fuel more black

[1969c10joe]

married with children? congrats. I got this advice from a barber decades ago...if your wife is unhappy then you will be miserable

[1969c10joe]

rpm kills more engines than total power output grumpy is right consider going up in displacement eventually

[cleszkie]

Am I missing something here? ALL indications are that there is too much fuel being run through the engine, and multiple people have pointed this out on multiple occasions. Why not step down to a smaller carb as many have suggested????? If you are thinking of selling this truck as a package, it will bring more if it actually runs properly. All the pricey top end components you have in it now mean nothing to a potential buyer if they are mismatched, or don't produce the performance due to improper carburetion. Unless that is, the buyer is buying it to part out, at a parts truck price.

[Mrturner1]

Originally Posted by cleszkie

Am I missing something here? ALL indications are that there is too much fuel being run through the engine, and multiple people have pointed this out on multiple occasions. Why not step down to a smaller carb as many have suggested????? If you are thinking of selling this truck as a package, it will bring more if it actually runs properly. All the pricey top end components you have in it now mean nothing to a potential buyer if they are mismatched, or don't produce the performance due to improper carburetion. Unless that is, the buyer is buying it to part out, at a parts truck price.

I figured the rings had to be going if there was oil all over the spark plug. Call me crazy but that seems like an indicator to me. Maybe GrumpyOldMan is right and it's fuel, but I don't get why it looks like black oil.

[1969c10joe]

there is more than one way to get oil in combustion chamber Iknow a guy who thought he blew a gasket when it was a loose spark plug wire

[1969c10joe]

it wouldnt hurt to check fuel pressure and set floats or put your other carb on. call me crazy but run engine pull plug and smell it does it smell like fuel?

[1969c10joe]

are all your plugs fouled or just some?if only some then yes probably oil does thismake sense?

[Mrturner1]

Well I'm working out of town so I won't be able to wrench on the truck till later this week. But are you guys saying it's probably just too rich and that's the black liquid on the plug? I thought for sure it could only be oil but after reading a bit it does make sense, because the plugs were all black and sooty, and if raw fuel gets on them it would make a black liquid kinda like dirty oil.

I think to really know for sure I'm gonna have to break out my new compression tester and see what the cylinders look like.

Somebody said earlier that there shouldn't be any fuel visible in the sight window, and on mine there's fuel halfway up the sight window. So Holley experts, is this why it's so dang rich? My vacuum is 6"Hg and power valve is now a brand new 4.5 so I'm ok there. Jets are 70/76 but I don't think that's an issue on the idle circuit. Somebody also said I need a N shaped screw driver but I don't know what it was I was supposed to adjust with it

[Grumpy old man]

Your answering all you own questions
black sooty plugs = fuel
Strong fumes from exhaust = fuel
fuel 1/2 way up site window = fuel

Everyone wants to see you win this battle but I'm beginning to believe we are all getting punked ?
You'll never tune any engine if you can't read plugs correctly . Pull any plug and wipe it on a clean white rag you'll see soot not oil
smell it ? Any hint of fuel ?

Now I'm not trying to give you a hard time but... your not going to build a high performance engine your first time out no matter how much $ you throw at it . And getting crazy over valve lash settings is overboard . If the directions say .0020 that's what you set them at period . You don't play with the numbers . Bigger and badder doesn't always work especially when dealing with carbs . Many guys suggested to forget the cracked block , but hey what do we know ? Many said you don't need the 750 dp ...well what do we know ? More than a few said those heads were ify at best but ... what do we know ? Timing takes less than 10 minutes to set but ... what do we know ? .....Well we know one thing none of this makes sense ... listen to some of these guys , they all want to see it work for you but have to use the information they give you and not reinvent the wheel .....

[Mrturner1]

Originally Posted by Grumpy old man

Your answering all you own questions
black sooty plugs = fuel
Strong fumes from exhaust = fuel
fuel 1/2 way up site window = fuel

Everyone wants to see you win this battle but I'm beginning to believe we are all getting punked ?
You'll never tune any engine if you can't read plugs correctly . Pull any plug and wipe it on a clean white rag you'll see soot not oil
smell it ? Any hint of fuel ?

Now I'm not trying to give you a hard time but... your not going to build a high performance engine your first time out no matter how much $ you throw at it . And getting crazy over valve lash settings is overboard . If the directions say .0020 that's what you set them at period . You don't play with the numbers . Bigger and badder doesn't always work especially when dealing with carbs . Many guys suggested to forget the cracked block , but hey what do we know ? Many said you don't need the 750 dp ...well what do we know ? More than a few said those heads were ify at best but ... what do we know ? Timing takes less than 10 minutes to set but ... what do we know ? .....Well we know one thing none of this makes sense ... listen to some of these guys , they all want to see it work for you but have to use the information they give you and not reinvent the wheel .....

I don't get it, I didn't worry about the cracked block because you guys said it was fine, I thought I bought a 650 carb but was given the wrong one by the parts guys, and I can set timing in 3 minutes? Apperently I sound like I'm arguing because that's the reaction I'm getting, but I just thought the wet black stuff was oil and obviously I was wrong. I've been following advice and got a few tools to start checking compression and vacuum but I'm working out of town now so I can't go work on the truck. I don't get how I'm rubbin people the wrong way but I suppose it doesn't matter that much.

[Mrturner1]

Originally Posted by RichardJ

>> I set the lash too tight, and if the lash is too tight then there's no buffer between the lifter and rocker arm and that's how you get a flat cam correct?<<

Buffer? What the hell do you think you're talking about?
If the valves are too tight, you run the risk of holding the valves off the seat or not letting the springs hold the valves tight against the seat for good heat transfer. That can lead to burnt valves.
If the valves are too loose, the valve train is noisy and really loose, hammering causing excessive wear.
The most important aspect of valve lash is to allow for heat expansion and not reach either of the extremes mentioned above. Hydraulic lifters self adjust to allow for expansion, never need readjusting and are much quieter.

Stop trying to use valve lash as a tuning aid.

The cam is not causing the rich mixture. The rings are not causing the rich mixture. A flat cam lobe is not causing a rich mixture.
You don't wipe out 16 cam lobes at the same time. If all the adjuster nuts are at approximately the same height, you don't have a cam problem. You did just adjust them. I have to assume you adjusted them correctly.

Stop flitting from one wild guess to the next.

Get rid of the vacuum advance. adjust idle down to 600 and see if the idle mixture screws are responsive to adjustments in or out from the 2 turns you set them at.
I'm making the assumption that your 2 turns out is a setting and not an actual adjustment. Use your vacuum gauge and a tach.

>>36 total all in at 3000 rpm.<<
Who cares. At this point it is more important to know at what rpm mech advance begins.

This guy got mad too. I must just sound like I'm not taking advice or something, although I assure you I'm listening to everything you guys say. I might not be correct when I take a shot at what may be wrong, but I am still learning. As far as I knew, the carb settings were all good to go. Mixture screws were exactly where member Hugger said to put them, idle speed was set wherever it needed to be after I set timing, and the rest of the carb stuff I don't know about yet.