Engine issues after new plugs? V8 though

[PortFJ62]

While replacing my headers a couple of weeks on the 62 with dirtgypsy(my personal mechanic) we decided to replace the sparkplugs and in the process ripped a couple of the wires trying to pull them off(the rubber section). So we were able to keep one of the wires(with a small tear) and put a universal wire in place of the really bad one along with new plugs. Since then when Im in 4th gear and above 45mph or so mainly up hill there is some hesitation like the engine is skipping a beat every now and then. Did not do this before, actually ran smooth as can be. What is the best way to troubleshoot this? Can I assume its either the bad wire or the one of the plugs?

 

[D'Animal]

Can I assume its either the bad wire or the one of the plugs?

Yes you can.

You did not mention if these were carbon fibre core wires or wire type wire. If they are the carbon core you may have broken the carbon up in the ones your were rough with. The spark is arcing between the breaks and when it gets to the spark plug it is not putting out the juice it should be.

 

[Dynosoar]

My old 2f was very touchy about plug wires. I am a strong believer in the OEM quality. I have a used set for a 2F I don't know if they are the same as the 3f set but I sell them real cheap, or call C-Dan I think a new set is only about $40.00.


Dynosoar

 

[D'Animal]

He will need two additional wires for the #7 and # 8 cylinder.

My old 2f was very touchy about plug wires. I am a strong believer in the OEM quality. I have a used set for a 2F I don't know if they are the same as the 3f set but I sell them real cheap, or call C-Dan I think a new set is only about $40.00.


Dynosoar

The hint is in the title.

 

[PortFJ62]

They are msd wires. Not sure about the carbon part though. These were on the truck when I bought it. So maybe I should 1st try replacing the other wire then? Does it matter if its another universal one?

 

[Trapper50cal]

An option

You should replace all the plugs (with gap set correctly, plus its not very expensive) then go through each wire and unplug one at a time and start it. It should run rougher until you find the original culprit. replace that wire.

 

[D'Animal]

If I understand the first post. It only happens in 4th going 45mph uphill. Basically lugging the motor. It could be pinging from low octane or ignition timing. Since it did not do it before he destroyed a couple of plug wires. I'm beting it is the wires.


You could pull the dizzy cap and see if the contact area for the spark plug wire in question looks the same as the others.

You should replace all the plugs (with gap set correctly, plus its not very expensive) then go through each wire and unplug one at a time and start it. It should run rougher until you find the original culprit. replace that wire.

 

[Trapper50cal]

could it be

Could one of the wires be discharging out through a crack before it gets to the plug?

 

[ntsqd]

I'm also thinking one of the strained leads is the problem. Lugging = high cylinder pressure = hard to jump the eletrode gap. Spark is lazy, if it can find a way to not jump that gap, it will.

Were it me I'd replace the whole set (I know that's not cheep) since they were all subjected to the same pulling or you may be finding yourself fighting this problem on and off until they all get replaced anyway.
Alternately, if you have a good crimper and the leads are all long enough, you could replace all of the boots and terminals. Cut the leads an inch or so at each end though, don't be tempted to just R&R the terminals w/o shortening the leads. And know going in that this may or may not be a permanent cure.

Put the spark plug ends on the spark plugs with a little dielectric grease smeared on the insulators or into the boots. That should keep them from sticking in the future.
And, never pull a plug lead off by the wire - always work the boot loose first.

 

[Elbert]

Make sure you did not cross the wires and get the firing order off. I generally use belden wires from NAPA...very good quality.

I would just get a new set of plug wires and verfiy the firing order. I had to use strait boot plug wires that were designed for a 99 pickup with 454, since I run the rams horn manifolds. Fairly expensive.

 

[PortFJ62]

Thanks everyone, gonna mess around with it today and see if I can find a bad wire.

 

[Waggoner5]

Definitely replace the wires. I am pretty sure those wires were factory Mercruiser, but any wire for a big block with an HEI distributor will work. Also, make sure that #5 and #7 are not crossed. It is a common mistake and will cause hesitation issues under load. Did the check engine light come on?
G

 

[PortFJ62]

Definitely replace the wires. I am pretty sure those wires were factory Mercruiser, but any wire for a big block with an HEI distributor will work. Also, make sure that #5 and #7 are not crossed. It is a common mistake and will cause hesitation issues under load. Did the check engine light come on?
G

Its ended up being the questionable wire we put back. Replaced it with another msd and runs smooth. No check engine light though.

Thanks everyone.

 

[lehiguy]

Commit this to memory; 18436572. That's the firing order to every Chevy V8 ever made and some Chryslers as well. Summit Racing has a wire kit (their own brand) that is inexpensive and has super low resistence. Usually you need to put the distributor ends on yourself.

 

[PortFJ62]

Commit this to memory; 18436572

Great, thanks for this.

 

[CruisinFJ60]

He will need two additional wires for the #7 and # 8 cylinder.




The hint is in the title.

Definitely replace the wires. I am pretty sure those wires were factory Mercruiser, but any wire for a big block with an HEI distributor will work. Also, make sure that #5 and #7 are not crossed. It is a common mistake and will cause hesitation issues under load. Did the check engine light come on?
G

oh yea....
I forgot that that was the gent that bought the 62 from you.