[Tav]

Hi guys
I have a SJ51 lwb Sierra with a 1.3 motor. Today I drove it into the workshop to kick start my build
So I decided to start on rust repairs first ( both floor pans an a corner of the firewall). But when I whent to start the Ute to clean up it won’t fire. Is there a way of checking the coil..? Just have no spark
Cher

[bumstein]

Checking the coil you either need a multimeter to see what the resistance is over the primary and secondary coils, or swap it with another one.

Interesting to know however what you have already checked and why you think it’s the coil? Are you sure there’s no spark? What leads you to think there’s no spark?

Just in case.. to see if there’s spark or not pop one lead off at a time and place it a few mm from one of the rocker cover bolts. I like to have a spare spark plug on hand, earth the thread (by popping it onto something earthed) and crank the motor. If there’s spark then you’ve got spark. If it’s a weak spark you’ll need to fault find that. If it’s a strong spark then your good as long as your spark plugs are ok.

If it’s been sitting for a long time I’d start with the simple things, how old is the fuel? Old fuel doesn’t ignite as well and may cause a problem. The diagnostic list is long from here but without knowing what you have already done or why you think it’s spark then difficult to elaborate.

[Tav]

Hi Bumstein
I cracked it over for a while with no luck so I checked the carbie an there is fuel been pumped. I then pulled a plug lead to see if I had spark. There was none so I pulled the cap off the rotor an cleaned all components still no spark. I then moved to the coil lead and the end that plugs to the coil was rusted an that’s when I turned to u guys because that’s about the extent of my knowledge.
I’ll get my mate to come check it with his meter after work. If it is stuffed what is a good replacement...?
Cheers

[bumstein]

Ah thanks for that!!

If the lead is rusted in then that is likely your problem. They have to have a good contact.

You might be able to clean it up a bit or just replace it, they aren’t too expensive especially if your just buying one lead. Personally I like to buy a set and replace them all at once, but that’s just my preference.

Just so we’re clear, when you pulled the lead to see if there is spark did you place the end of it near something well earthed to see if it arcs across? The end of the lead won’t spark without it being a mm or so from something earthed like a head stud. Wouldn’t like you to keep chasing a fault in the wrong direction

If the coil lead has been replaced and it still doesn’t spark then yep, move on to the coil.

[Tav]

Yes I used a small screw driver to earth the lead to a head bolt with no luck. When I finish work I’ll have a closer look at the lead an then go from there

[bumstein]

Great [emoji4] be very suspicious of the rusty contact! Let us know how you go