Ignition problems

Lyn Smith · 07-17-2023, 04:32 PM

Got a sbc engine on my run in stand. Have a complete digital 6al, blaster 2 coil ,85551 distibutor. Start up the engine and it idles for a few seconds and then it starts exploding out of the exhaust like a string of firecrackers. Timing is ok. Put a stock HEi in it and it runs fine. All wires are isolated for no interference. Anyone ever experienced this before?

Jeff Niceswanger · 07-17-2023, 04:36 PM

I've had 2 MSD rotor buttons burn thru the bottom and cause identical issues. Rotor looks new on the top but they burn right through the bottom. Have a look, it only takes a second. I think they re designed that rotor a while back to help this issue.

Lyn Smith · 07-17-2023, 10:45 PM

Tried a couple new rotors, same results. Tried numerous new, used boxes coils. Same thing. Got thru to some one at MSD they said it has to be something in the pick up. Same results with a new distributor, and a previously good used one.

Glenn Briglio · 07-18-2023, 07:07 AM

Same ignition wires between the two distributors ?

Monte Howard · 07-18-2023, 04:30 PM

Had a friend bring me his race car that was doing the same thing. What I found was, he had replaced the pick up coil and put it in backwards and that caused reverse polarity.

Lyn Smith · 07-18-2023, 05:16 PM

Yes if you reverse those wires on the pick up it will advance the timing 12 degrees and then it will back fire thru the carb. This is all thru the exhaust. MSD rep told me the only way I will get that extremely loud banging thru the exhaust is having the timing retarded. I have had 3 different distributors in it. With the HEI set up in it the motor just sits there and purrs. Thanks every one for the info. Will let you know what I find out. If I ever do .LOL

SDT1DYI · 07-18-2023, 09:27 PM

I assume you replaced the distributor cap as well as the rotor?
Just recently a new MSD cap was purchased and installed misfiring occurred.
Put the old one on, ran fine.

Steve Teeter Stk/SS 620

Lyn Smith · 07-19-2023, 02:54 PM

Changed a few more components in the ignition and the problem finally went away. Thanks for all the suggestions.

Larry Merk · 07-19-2023, 03:52 PM

Quote:

Originally Posted by Lyn Smith

Changed a few more components in the ignition and the problem finally went away. Thanks for all the suggestions.

And the component that caused the problem was?????

mike britt · 07-19-2023, 08:19 PM

Suspense is killin me.

07-17-2023, 04:32 PM	#1
Lyn Smith VIP Member Join Date: Dec 2001 Location: Pontiac,il. Posts: 1,121 Likes: 217 Liked 841 Times in 156 Posts	Ignition problems Got a sbc engine on my run in stand. Have a complete digital 6al, blaster 2 coil ,85551 distibutor. Start up the engine and it idles for a few seconds and then it starts exploding out of the exhaust like a string of firecrackers. Timing is ok. Put a stock HEi in it and it runs fine. All wires are isolated for no interference. Anyone ever experienced this before?

07-17-2023, 04:36 PM	#2
Jeff Niceswanger Senior Member Join Date: Jul 2003 Posts: 771 Likes: 588 Liked 839 Times in 293 Posts	Re: Ignition problems I've had 2 MSD rotor buttons burn thru the bottom and cause identical issues. Rotor looks new on the top but they burn right through the bottom. Have a look, it only takes a second. I think they re designed that rotor a while back to help this issue. __________________ Jeff Niceswanger 3740 SS

07-17-2023, 10:45 PM	#3
Lyn Smith VIP Member Join Date: Dec 2001 Location: Pontiac,il. Posts: 1,121 Likes: 217 Liked 841 Times in 156 Posts	Re: Ignition problems Tried a couple new rotors, same results. Tried numerous new, used boxes coils. Same thing. Got thru to some one at MSD they said it has to be something in the pick up. Same results with a new distributor, and a previously good used one.

07-18-2023, 07:07 AM	#4
Glenn Briglio VIP Member Join Date: Nov 2002 Location: Massapequa Park,NY Posts: 1,206 Likes: 1,729 Liked 822 Times in 264 Posts	Re: Ignition problems Same ignition wires between the two distributors ? __________________ 1989 Camaro Iroc-Z I/SA B&B Auto Machine Shop.

07-18-2023, 04:30 PM	#5
Monte Howard Member Join Date: Nov 2002 Location: Potomac,IL Posts: 268 Likes: 1 Liked 48 Times in 14 Posts	Re: Ignition problems Had a friend bring me his race car that was doing the same thing. What I found was, he had replaced the pick up coil and put it in backwards and that caused reverse polarity. __________________ Monte Howard 3209 STK, 3208 SS

07-18-2023, 05:16 PM	#6
Lyn Smith VIP Member Join Date: Dec 2001 Location: Pontiac,il. Posts: 1,121 Likes: 217 Liked 841 Times in 156 Posts	Re: Ignition problems Yes if you reverse those wires on the pick up it will advance the timing 12 degrees and then it will back fire thru the carb. This is all thru the exhaust. MSD rep told me the only way I will get that extremely loud banging thru the exhaust is having the timing retarded. I have had 3 different distributors in it. With the HEI set up in it the motor just sits there and purrs. Thanks every one for the info. Will let you know what I find out. If I ever do .LOL

07-18-2023, 09:27 PM	#7
SDT1DYI Member Join Date: Nov 2016 Location: Indianola Washington Posts: 356 Likes: 0 Liked 394 Times in 124 Posts	Re: Ignition problems I assume you replaced the distributor cap as well as the rotor? Just recently a new MSD cap was purchased and installed misfiring occurred. Put the old one on, ran fine. Steve Teeter Stk/SS 620

07-19-2023, 02:54 PM	#8
Lyn Smith VIP Member Join Date: Dec 2001 Location: Pontiac,il. Posts: 1,121 Likes: 217 Liked 841 Times in 156 Posts	Re: Ignition problems Changed a few more components in the ignition and the problem finally went away. Thanks for all the suggestions.

07-19-2023, 08:19 PM	#10
mike britt Member Join Date: Mar 2013 Location: Italy, Texas Posts: 141 Likes: 203 Liked 43 Times in 19 Posts	Re: Ignition problems Suspense is killin me.