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Discussion Starter #1
Hey Guys, I started up my car for the first time this weekend! It was bitter sweet...

Here's some background and what I did: '68 RS Vert with a 290 hp crate 350 dressed in 327/275 clothes. EVERYTHING is brand new. Wiring from AAW and customized for HEI. Original points dist. rebuilt and converted to HEI, battery and cables, etc...

I fired it up for the first time and it hit immediatly, but ran bad. Burned my eyes terribly and I knew it wasn't hitting on all the holes. But, since it was my break in, I didn't want to shut it off.

Well, a few minutes into the run, I noticed smoke coming out of my voltage regulator! I shut it down, and the back of the VR was HOT!! I read that I'm supposed to have a ground wire from the base of the VR to the rad supt, so I had one on there. I took the wire off the rad supt from the VR and it sparked! Umm...I'm no electrical guru, but a ground wire shouldn't spark!

I fired it back up without the ground wire attached and finished my break in. It still ran bad. Pulled the plugs. About 4 of them looked bad. I didn't have any new ones in stock, so I changed it out with 4 used ones I had laying around. Engine ran much better?

I didn't want 4 new and 4 old plugs in there, so I went and bought a whole new set. Fired it up and it runs terrible again.

Do you think I toasted my voltage regulator? It was a brand new Echlin from NAPA. Would the regulator being bad cause the ground from the case to spark?

Here's something else. My car doesn't have the fenders on it as I wanted to fire the engine up first in case it had to come out. The rad sup is obviously mounted on rubber. I'm thinking maybe the grounds on my rad supt are useless because they all end in rubber? Should I ground the rad support with some jumper cables or something to the body to immitate the fenders being on there, thus "grounding" the radiator support?

Another funny thing to add to the mess. I have a quick disconnect on my battery. While the engine was running badly, I disconnected it. It stays running, but definitely runs even worse.

Could all these issues be related? Any other theories? If the VR was bad and not properly grounded, could that possibly affect having proper spark?

Sorry, I know I get wordy, I just wanted to get as much info as I could on here for your theories. Thanks for taking the time, and any help is highly appreciated. Briani
 

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It is not uncommon for a car to stay running with the battery disconnected. Back when I was a kid we used to disconect the battery with the car running to see if the altenater was bad or not. If the car died when disconnected usally that was a pretty good sign the altenater was bad.
 

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Brian - It sounds like you have a couple problems. First though it's not optimal don't be afraid to shut down during initial run-in if there are problems. Go back and double/triple check both your alt/voltage reg wiring and your plug wires. It really sounds like you have a couple plug wires swapped or some bad crimps causing the mis-fire. The fact that your voltage reg was hot could be because the coil in it is the weak link and you have a short somewhere along the way, the grd sparking is another good sigh of a short somewhere.
 

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Why can't I turn off my engine? You wired up the alternator wrong! Hey, it's only two small wires but you can swap them. What happens is that the output of the alternator feeds it's self and even though you turned off the ignition, as long as the alternator is spinning, it feeds the car and keeps running.
see the tech section here.
 

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I run my engine regularly without any alternator at all (just to mule the car around). You should be able to disconnect the alternator / regulator and run the car from the battery with a charger (for the 20 minutes or so required for break-in). Rule out other problems before getting too involved with the charging system. Break-in is more important at this point. Have a volt meter handy to verify the battery voltage is high enough. If some electrical short cause the system voltage to droop too low it could cause all sorts of ignition issues.

Do you have a Holley carb on it? It's common for a back fire to rupture the power valve diaphram which will make it run richer than a pig. If your diddling with timing and things (like you normally would have to for a first start) a back-fire isn't out of the question.
 

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Discussion Starter #7
Okay, thank you for your input and patience. I'm more of a body man than a mechanic, but I can usually hold my own. My weakness is wiring, and of course that's where I have my issues.

Here's what I did last night. I took some jumper cables and grounded the rad supt to the body. Fired it up, and it ran terrible. Burning my eyes and missing and jumping around exactly like I've got some plug wires wrong. Double checked my wire routing, yep clockwise,18436572. Bumped the engine over to the squeeze stroke, put the mark on 0 and pulled the cap. Pointing right at #1 on the cap. Took my timing light and put the clamp on each plug wire while it was running and they all light up the light. Could I be 180 deg off? It's not supposed to blow your finger out of the hole on the other upstroke, so I think I'm at TDC. I know I could verify by pulling a valve cover, but I really don't want to.

I'm pretty sure my timing is close. It fires right up and doesn't run on after shut down. No starter drag. I've got it at 4 deg before at idle with the vac advance unplugged. It has never back fired, just runs bad.

I have a rebuilt Quadrajet from Vintage Muslecar, not a Holley.

I check voltage at the battery, alternator post, at the supply side of my coil and all seem fine. Here is something that appears weird to me. There may be a simple explanation to it, but it doesn't make sense to me.

I read you could pull the negative cable off and put a test light inbetween the cable and the battery. If it lights the light, you have a draw on the battery. Well, it didn't light my light, but while I had it disconnected, I started probing around. I put my neg lead of my meter on the neg batt terminal and put the pos lead on some other various places like the engine block, the upper control arm bolt, etc... and I was getting voltage readings of 10 or 11 volts!!! Should I be getting a reading doing that? Seems like I've got voltage running through my engine block? I did the same thing with my test light, and it wouldn't light it? That's got me confused, but like I said, I'm a body man...

I have all three ground straps in place from subframe to block and body, etc...

I probably need to attack this as two separate problems I guess. An engine running bad problem, and a charging system problem if I have one. I just fear they are related.

Funny thing is, my credit card took a major beating when I ordered ALL new wiring from AAW. I didn't want to mess with wiring problems because I hate them, and I'm terrible at working on them. I even got plug wires and battery cables from them and it all seems money.

Thanks again in advance. Brian
 

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68holdon... you are lost dood...
Back when I was a kid we used to disconect the battery with the car running to see if the altenater was bad or not. If the car died when disconnected usally that was a pretty good sign the altenater was bad
I can't believe some of you guys. FIRST OF ALL, the battery disconnect trick was for GENERATORS... not ALTERNATORS. An Alt makes AC voltage and converts it to DC via the rectifier bridge and diodes (3 positive 3 negative). When the rectifier or diodes are taken out of the charging circuit for ANY reason (such as disconnecting the battery cable), or shutting off the battery master disconnect without the other part that opens the field circuit so the engine will die and no damage will occurr. Disconnecting a battery with the car running can put a 600 AC voltage spike through your entire electrical system and fry everything, blow up light bulbs, ecm's, stereo's or anything in it's path. Alts put out a sine wave much like the 60 hz wave in 110 volt house electrical, the rectifier bridge and diodes cut off the top of the sine wave which is what happens to convert AC to DC voltage. I suggest you go to this web site and learn how an Alt works before giving out advise that can AND WILL cost somebody a buttload of money.

How Alternators work >>
http://www.bcae1.com/charging.htm

Then look at master disconnect switches to see the difference.

Battery only disconnect switch>>
http://www.colehersee.com/04resource/Tech%20Info/IF-126.pdf

Battery and field circuit disconnect switch >>
http://www.colehersee.com/pdf/IFs/IF-109.pdf
 

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Discussion Starter #9
Good info, thanks for posting. So...bad idea to disconnect the neg batt cable while the engine is running...noted!! I don't think I hurt anything. It was just for a second and it runs just as bad after as before I did it. Thanks, Brian
 

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No problem Brian... :beers:
unfortunately, this is one of the most mis-understood things there is concerning electrical systems, and the way us old farts used to check out out our 55 Chevy charging systems doesn't apply to cars with an alternator :noway:. Now days all you need to run a blender off of your car is to disconnect the batt cable with the engine running...lol (just kidding ;), although it does produce AC voltage, the damage comes from the instant spike that goes through the electrical system)
 

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You say you put a timing light on it to confirm you had spark, but you didn't say what your timing was, only that it was pretty close. Timing is always a critical tweak on a fresh startup. If you were 180* out, the engine wouldn't run at all and it would back fire through the carb, cough, and fart.

If you measured between the battery (-) and block (for example) with the ground lead disconnected, you likely would see voltage. The voltage drop test is only valid when the circuit is connected and loaded. Check your system voltage when it's bucking and farting. That will be the critical reading. Just avoid measuring the 12V feed to the coil lest ye meter go poof.

The ground cable should be connected to the block, so even though the other grounds may be missing or poor, it should not affect the engine running unless you have an MSD box or computer grounded to the body.

I'd encourage you to separate any electrical issues from an engine issue by disabling the alternator (disconnect the field plug) and run it from the battery with a charger attached. Once you're satisfied that the system voltage is good and that your timing etc. are good the engine should run. Afterward you can dig deeper into the electrical.
 

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Discussion Starter #12
Okay, thanks all for the info.

I do think it's a good idea to treat it as two separate problems. I'm not even sure I have a charging system problem yet. I just saw the smoke coming from the VR and figured that wasn't good.

Thanks for the info on the grounds. Good to know it's probably not related to my engine running badly.

My timing is set at 4 deg. BTDC at idle with the vac adv disconnected. That's the spec for the 327/275. I have a 350/290, but I figured that spec would be close, and I could fine tune it later.

Idle mixture screws are at 2 turns out. Vacuum is 17 at idle.

I have 12 volts at the HEI. As I mentioned, it's a Dave's small body conversion, so I measured it with the key on at the plug that goes to the HEI. I will double check this, but that's what I remember.

Plugs are AC Delco R45TS I think. I have them gapped at .045. Spec for the 327 is .035, but I remember asking the dealer I got my crate engine from, and they told me the plug # and gap.

I'll do more checking throughout the week and on the weekend.

One guy I talked to is thinking carb problem, but I put a brand new set of plugs in it, and it ran bad from start up before it even had a chance to get the plugs wet. I don't think it's a carb issue, but I could be wrong. I think it's a spark issue.

Thanks for info, and give me more ideas if you have any. Thanks, Brian
 

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Could be a valve adjust issue as well.

I'd be inclined to "hot wire" the car with the rest of the elec system completely disconnected (alternator, accessory wire, etc).. Run a jumper wire from the + side of the batt to + side of coil. + batt cable to starter, - to engine block with a charger on the batt. Jump across the + cable to the S terminal on the solenoid with a remote starter button, finish the cam break-in and see how it runs. I assume you have a mechanical fuel pump.
 

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is the gas still good? move timing up to 8*, check cap and rotor on distributor,get a new v/r. check for vaccuum leaks and a wire shorting out near coil/dist. let us know
 

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Al's got a good point. Valves.
Three things for an engine to run: Properly timed strong spark, proper compression and fuel. That's it.
I'd pull the plugs and check compression first thing. A mal adjusted lifter is gonna torpedo anything you do. Think 'compression'.
 

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If you have a stock wire harness then you will prob see a fire start after 20 min. The stock resistance wire is for a stock coil not an aftermarket set up. I would call the tech guys at the place you bought it from and find out how to wire it correctly. Also make sure your wires are in correct order. Don't you have a problem with the HEI rubbing the firewall? Good luck...
 

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Discussion Starter #17
Eye69: I have a Dave's small body HEI and a new wiring harness from AAW modified for HEI, so no issues there.

Fred & BPOS: Thanks for the ideas. I've never really thought about a compression check. The engine is now broken in, and I've never heard a tick, knock, or any funny noises at all. It just seems like it's not hitting on all the holes. Could be a valve is too tight I guess. I pulled the valve covers off before I installed the engine and looked things over, but I didn't really check anything.

My dad has a compression checker. I'll run over there this weekend and run one on it.

AJ: The gas is brand new 91 octane. I agree, I'll probably have to move the timing once I get it hitting on all the holes. I had 17" of vacuum at idle, so I don't think that's an issue, but I'll make a note to check.

The weirdest thing about this whole deal is that after the initial run in, I changed some of the plugs out and the thing ran fine.

Here's what I did last night: I pulled the distributor and moved it a tooth counter-clockwise. I was scared it was off a tooth. I reinstalled it, and it didn't even hit at all. Moved it back, and it started and ran on 5 or 6 cylinders again.

I confirmed the rotor is at #1 with the timing mark on 0 deg at TDC on compression stroke. All wires are going to the right hole. Cap, rotor, and plugs are all new. I did notice the plugs have some black on them with maybe 5 minutes of total run time on them. Idle screws are at 2 turns out. Is that too much?

I verified I have 12 volts everywhere. At the battery, at the wire going to the dist, after the dist, and at the coil. In fact, I pulled the coil wire off the coil side while I was bumping the engine over to get it to TDC, and the spark was jumping out of the inside of the coil and going to the terminals on the side of the coil! I think it's working fine!

While it was running badly, I did bump the timing up to 8 deg.

I'm not even concerned about the charging system issue if I even have one, but while it was running, I did check the alternator, and it's putting out 14 volts.

Here's what I'm going to try next. Let me know what you think.

#1: Pull the plugs and spin a compression test.
#2: Pull plug wires and ohm them out to make sure they are good.
#3: If all that checks out, I'm going to reinstall the plugs in the boots, but not the engine, and bump the engine over and watch what each one does. If I can bump it over slowly enough. I should be able to watch each one fire in order.
#4: My mechanic has a tool you can plug into the plug wire to measure spark. I'm probably going to borrow that too.
#5: If all of the above fails to help, I guess I'll be pulling the carb?

Thank you for all the help. Brian
 

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Brian,
Since you're looking toward the carb, Is the choke opening? Sorry to ask, but sometimes the obvious is often overlooked. You don't mention it anywhere above. Are there any internal leaks or dribbles of fuel at idle? Sometimes Qjets can leak a little after a rebuild, and even need double or thicker top/bowl gaskets to seal up. A leak could quickly foul plugs and make the engine act like you described......Jb
 

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Don't rule out the possibility that the harmonic balancer may have slipped or the balancer / pointer aren't a match. On the first startup, I usually set the distributor clamp just snug enough that I can move the distributor by hand. Then I'll use a remote starter or have a helper crank it while I twist the distributor until it runs smooth (without "setting" the timing).

Find TDC and see if the pointer lines up. Typically you'd use a piston stop for that. Replace plug #1 with the stop and rotate the engine clockwise by hand until it stops. Mark the balancer where the pointer aligns. Now turn the engine counterclockwise until it stops again. Mark the balancer once more. Your timing mark will be (should be exactly half way between your two piston stop marks.

I use a piece of 1/4" soft copper tubing as a piston stop. I stuck it in the hole and let the piston squeeze against the head.
 

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Discussion Starter #20
Johnny B: I have checked the carb. It appears to be working fine from what I can see. It squirts when it should, and doesn't drip when it shouldn't. Choke starts off closed, and opens just like it should. I'm hesitant to look there because the guy that did my carb is money.

dnult: Another thing on the list to check I guess. I had the GM dealer send me a brand new balancer with the crate engine. I've verified several times the plug fires #1 on TDC of compression stroke. It's something I'll keep in mind though.

Thanks again for the advice guys.

I think I have found a potential problem. I'm using the stock Delco Remy 293 coil, and I don't see it listed in Dave's Small Body HEI instructions. I'm REALLY hoping I found my problem.

I sent him an email to confirm. If I have spark when I should have spark, but it's just weak, this could easily be my problem. Stay tuned... Brian
 
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