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Dave Rifkin
10-27-2013, 02:51 PM
What would be the symptoms of an engine with a few plug wires mixed up? I have a 1969 L46 Corvette that, in my opinion, has never run up to it's potential. I have taken it to multiple Corvette "specialists" and no one has been able to get it to run to my expectations.
My last mechanic performed a tune up and told me that a previous owner / mechanic had installed the distributor off a few teeth. Rather than remove the distributor this person made the adjustment by rearranging the plug wires. (None of this makes sense to me as I would think I would have noticed that car running rough or something).
The latest mechanic says he removed the distributor and reinstalled it correctly.
Ever since he did that the car runs rough when I step on the gas. He told me that the carb needed to be rebuilt so I sent it to Eric Jackson. Eric said that the carb was in need of work so I was hopeful that the car would come to life once it was reinstalled.
While the car does pull stronger it still runs rough when I step on it. I can't help but think that my new mechanic didn't do me any favors by messing with the distributor.
I think he created a new problem but, I need to know how a car would run if one or two wires were mixed up.

I am desperately trying to find someone who can get my car to run like I think it should. I am so disappointed, and frustrated, that I am considering selling the car since I no longer enjoy driving it.

Please help!!!

Charley Lillard
10-27-2013, 02:56 PM
Check the wires yourself. 18436572 is the firing order # 1 is front drivers side. 1-3-5-7 front to back on drivers side. Pass is 2-4-6-8 front to back. Find the # 1 wire on the cap and check them to make sure they are in order.

Dave Rifkin
10-27-2013, 03:08 PM
Would mixed wires cause the car to run rough when you step on the gas? It idles smooth but, gets rough when I give it any gas.

GreenLS6
10-27-2013, 03:25 PM
Whats your initial timing at? and how much vacuum is it pulling?

njsteve
10-27-2013, 03:29 PM
It is very easy to mix up #5 and #7 since they are next to each other in the firing order, and on the cap. The car will run slightly off from the resulting wrong order of firing.

When they talk of the distributor being a "few teeth off", it means it was installed in a position that the distributor base and the vacuum advance unit may not be in the ideal position to get the ignition timing set correctly. The advance unit may hit the firewall or the intake runner. By moving the entire set of plug wires over one terminal or two positions on the top of the distributor, you are doing the same thing as if you pulled the distributor and reset the position correctly.

It is kind of like setting your clocks back for daylight savings time. The clock is still telling you the right time, it is just moved back one position.

You probably need to have the distributor rebuilt and have the advance curve set properly. Sometimes the vacuum advance canister goes bad and either doesn't work anymore or creates a vacuum leak. If the mechanical weights are sticking, you won't get advance at all. I have a guy out west do mine and the difference is amazing when you have a properly operating distributor. Lazy advance curves will make a car run crappy and slow.

Dave Rifkin
10-27-2013, 03:34 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GreenLS6</div><div class="ubbcode-body">Whats your initial timing at? and how much vacuum is it pulling? </div></div>

I don't know as I, unfortunately, don't work on the car.

Salvatore
10-27-2013, 03:52 PM
I am with Steve. Need to get the distributor done on a machine and set up correctly. You know that carb is right so eliminate the distributor problems and maybe even a cracked cap or bad rotor. Any small or half decent shop in your area should be able to do that. Thats a drag racing mecca around your area.

MosportGreen66
10-27-2013, 03:57 PM
Dave, I sent you a PM... give me a ring sometime.

Dan

Alss
10-27-2013, 03:59 PM
Dave..I'm in Somerset..if you bring it up I'll look at it.

Norwood
10-27-2013, 10:12 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: njsteve</div><div class="ubbcode-body">It is very easy to mix up #5 and #7 since they are next to each other in the firing order, and on the cap.
</div></div>


Steve, I think they are all next to each other on the cap and in the firing order since the wires are installed on the cap in the firing order......LOL so 1 is next to 8 wich is next to 4 which is next to 3....Maybe you ment on the plug.....

njsteve
10-27-2013, 10:18 PM
I meant on the plugs themselves. I have seen people, myself included, connect the #5 cable on the #7 plug and vice versa.

Alss
11-18-2013, 10:21 PM
OK guys..I have Daves vette here in my shop..its a very nice 55k mile car..right Dave? <<GRAEMLIN_URL>>/dunno.gif sure looks the part. went and picked it up over the weekend and just by pulling it the trailer it was running like a locomotive!..something sure was amiss..no pun intended.:)
stated by doing some basic checks..here is what we found:

Daves vette:
http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7891-img_1992.jpg

pulled the shields off and took a peek:..sometings not right here
http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7892-img_1993.jpg

Couild this be a vacumn line off?..to the vac advance?..
http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7893-img_1994.jpg

and what about this vacumn port??
http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7894-img_1995.jpg

here are the sparkplug..they all look good firing wise, but check out #6 http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7895-img_2002.jpg

so..pulled the dist out and its....fugly!..sticky... hard to turn etc. mech advance wieghts dont move so good either, so..Its on its way to TI specialtied in Indiana for a full restore..dist, TI box and coil, and all have correct numbers and dates!

http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7896-img_2005.jpg
man the TI box is a bitch to get out!!..compression test tomorrow for laughs and giggles.

PxTx
11-18-2013, 10:31 PM
Looking at the way the Vac Advance was clocked, I would guess a tooth off is at least part of the problem.

Alss
11-18-2013, 10:32 PM
this is the dist with the motor at TDC #!


http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7897-img_2003.jpg


observe the rust in the dist. <<GRAEMLIN_URL>>/frown.gif..but nice orignal parts!!!

http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7898-img_2004.jpg
http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7899-img_2006.jpg
http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7900-img_2007.jpg

Dave Rifkin
11-18-2013, 10:36 PM
As far as I know the mileage is correct on the car. I cannot thank Albert enough for tackling this challenge. As I have mentioned before, I had this car to numerous &quot;Corvette experts&quot; and none of them picked up on these things that Albert found in the short time he's had the car.

Albert forgot to mention that the distributor was not installed correctly; when he brought the #1 cylinder to TDC the rotor was pointing to the #8 cylinder instead of #1. The plugs were gapped at 42 instead of 35 which is what Albert said would have been recommended.

I can't wait to see how much better she runs when I get the car back. After 8+ years I'll finally have the car I had hoped I'd have when I first bought it.

Xplantdad
11-18-2013, 10:37 PM
Cool that you're getting the help that you need. Albert rocks! <<GRAEMLIN_URL>>/headbang.gif

Alss
11-18-2013, 10:42 PM
http://www.yenko.net/ubbthreads/pics/usergals/2013/11/full-526-7901-img_1999.jpg

Alss
11-18-2013, 10:44 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Dave Rifkin</div><div class="ubbcode-body">As far as I know the mileage is correct on the car. I cannot thank Albert enough for tackling this challenge. As I have mentioned before, I had this car to numerous &quot;Corvette experts&quot; and none of them picked up on these things that Albert found in the short time he's had the car.

Albert forgot to mention that the distributor was not installed correctly; when he brought the #1 cylinder to TDC the rotor was pointing to the #8 cylinder instead of #1. The plugs were gapped at 42 instead of 35 which is what Albert said would have been recommended.

I can't wait to see how much better she runs when I get the car back. After 8+ years I'll finally have the car I had hoped I'd have when I first bought it. </div></div>

I cant take all the credit, my buddy Joe is the driving force on the diagnostics..he's a sharp cookie..seen it all <<GRAEMLIN_URL>>/grin.gif ..he may chime in here later.

Alss
11-18-2013, 10:46 PM
OK corvette guys..whats with the tach drive cable..is there supposed to be a 90 deg connector in the back of the distributor for the tach cable??..I see they make a aftermarket one but cannot find anything on a OEM one...sure could use one here!!....Mosport you out there??:)

Alss
12-03-2013, 02:47 AM
Did a compression check on Daves car today..shes a healthy girl for sure. Here are the numbers:

http://www.yenko.net/ubbthreads/pics/usergals/2013/12/full-526-8383-img_2021.jpg


Distributor is still at least a week out..I hope, I'm ready for it when it comes <<GRAEMLIN_URL>>/grin.gif

Alss
12-13-2013, 01:41 AM
Distributor is back...all nice and new!
http://www.yenko.net/ubbthreads/pics/usergals/2013/12/full-526-8544-img_2031.jpg

started changing out the spark plug wires..they were new but not correct

http://www.yenko.net/ubbthreads/pics/usergals/2013/12/full-526-8545-img_2044.jpg

good thing we changed them..this one was cut almost half way thru by the shield!

and whose idea was all those shields!..running those plug wires was interesting to say the least.
will be fun putting them all back on again.:)

Here is the coil wire that had been cut and put back together..twisted and taped!! <<GRAEMLIN_URL>>/dunno.gif..come on!

http://www.yenko.net/ubbthreads/pics/usergals/2013/12/full-526-8546-img_2034.jpg


have to reinstall the TI box and she shoould fire up...cant wasit to hear this one run right!!..350 350 should be a healthy mouse! <<GRAEMLIN_URL>>/naughty.gif

Dicky
12-13-2013, 02:41 AM
I see you got the 90 degree drive for the tach. <<GRAEMLIN_URL>>/worship.gif

Good job. <<GRAEMLIN_URL>>/biggthumpup.gif

Dicky <<GRAEMLIN_URL>>/flag.gif

firstgenaddict
12-13-2013, 08:19 PM
I love 69 L46's, not having an Aluminum intake and Holley leads to their lack of recognition thus turning out to be a great buy for someone looking for a nice Early 3rd Gen small block runner... if they would have only utilized or optioned the BB hood.

Joe69Camaro
12-14-2013, 12:03 AM
Great Job Al... Lots of fun and Pulled Hairs on this on.. Brought back the hands of time for Me..
Being a Previous Vette owner as well . Wiring is a Major issue as well.. Wiring and Grounds Played a Big factor as well !!
Sounded great today when you fired it up !!! Rusted Parts and age effect us all Green wires and poor splices don't work well , and complicate issues...
1 more day , and It will Jerk the tires ;-)

Alss
12-14-2013, 01:24 PM
Its amazing you remember all that stuff ya old fart!<<GRAEMLIN_URL>>/grin.gif...Joe is the driving force on the diagnostics and making stuff...&quot;right&quot; again.

it runs again..sounds much better, too bad all the snow..no test drive...,yet:)

http://www.youtube.com/watch?v=gaJfDUS4QqE

Joe69Camaro
12-15-2013, 12:45 AM
LOL Albert... Its nice to be appreciated.
A lot of the late 60's and early 70's seem to be a tad bit Blurry..
Not sure if it was Car speed and octane fumes or What.. But I get those flashbacks to remember the important things. The rest is feel .

Having this Helped .... http://www.yenko.net/ubbthreads/pics/usergals/2013/12/full-5887-8562-scan0027.jpg

Dave Rifkin
12-21-2013, 03:35 PM
Well the car is home again; Albert and Joe just dropped it off and I cannot thank them enough for everything that they did. The car has never run better.
This is an early Christmas present to myself; I can't wait to take her out for a nice long drive.

Albert / Joe, thank you once again for offering your services. In the eight years I have owned the car it has never run like an L46 should. I spent good money taking it to Corvette &quot;specialists&quot; and each one did nothing but take my money. You two are true car enthusiasts and treated my car as if it was your own; I can't thank you enough.

Salvatore
12-21-2013, 04:13 PM
Great job. Like having a new car!

Joe69Camaro
12-21-2013, 08:45 PM
It was a Pleasure Meeting you today Dave.
The look on your face , and Smile after the road test with Albert Made my weekend !!!
That's what its all about ... <<GRAEMLIN_URL>>/3gears.gif

Xplantdad
12-21-2013, 09:29 PM
Great job guys! That's what makes this site the best out there!

miket1
12-22-2013, 05:55 PM
Looks like Joe &amp; Albert are actually good experienced ,,Mechanic's,, who know how to repair our older muscle cars correctly.
Good job guys.

talwell
12-22-2013, 11:57 PM
Based on this thread and what I see - I would have to say that the so called &quot;Corvette experts&quot; might only be that in name. None of the problems that your car had require even the specialty of a Corvette specialist to resolve. It really bothers me when people proclaim themselves to be experts, charge accordingly and have no clue what they are doing. Whomever touched your car last needs to reconsider their career. You are lucky you finally got it into the right hands and got it all resolved correctly before throwing more good money at bad mechanics.

Regardless - time to enjoy. Great looking car and love to see them so original.

-Todd

Alss
12-23-2013, 12:38 AM
Todd, Mike..you guys hit it on the head..the previous &quot;specialists&quot; did not even have basic mechanical skills...or gave a damm about what they were doing. I am by no means a mechanic..I am a avid hobbiest....Joe, on the other hand is a retired experienced ASCE certified master tech with 10-40 in his viens! <<GRAEMLIN_URL>>/smile.gif. He likes a good challenge!
What really pisses me off is, Daves car is a really nice original car!!..even with its low mileage, so many cheap short cuts were found! Does'nt anyone do thier job correctly anymore??
Dave..glad to help out, was a fun side project for us. Let me know how that long drive goes <<GRAEMLIN_URL>>/smile.gif