Thread: Proper engine grounding/Ground straps

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Just wondering what's the proper technique for grounding a small block chevy... I recently reinstalled my intake and when I was screwing the bolts back in they were sparking. Of course I still had the battery hooked when doing this which I shouldn't have. I'm thinking this has to be from an inproper ground or lack there of. The only ground I have is from the negative on my battery to a bolt on my water pump. I know this isn't the best way to do things. Sooo where can I ground my 400 from the block? Also doesn't the starter need some sort of ground? Any suggestions greatly appreciated.

The large negative cable should bolt to the block. I use a star type
lock washer and attach it to a bolt hole below the water pump.
Then you should have a smaller black wire from the negative battery post to the body.

from bat to motor, from motor to firewall AND chassis. if i was putting my intake on and had the ign. sw. off and i was screwing the bolts back in and they were sparking id be leaving. now thats a new one. glade you didnt spell no gas out of the carb.

I know that sounds funny but thats the truth. After I removed the positive cable from the battery it didn't spark anymore. Thanks for the replies.

well of course if you removed the cable from the battery its not sparking... i dont think ground was neccisarily the problem though... i'd look for a bare wire or something else shorting on your block before you run into some much worse problems down the road... like an engine fire.... the sparking was caused by something energized hitting a ground... which would most likely be your block that was the ground... and a wire/coil/something shorting on to the block

Originally posted by onemangang
I know that sounds funny but thats the truth. After I removed the positive cable from the battery it didn't spark anymore. Thanks for the replies.

for it to a spark at the intake something on the intake was trying to ground like one of the sensers. but for it to do that the key would have had to been on.

ps if any gas had of been on the motor it would have caught fire.

You're supposed to disconnect the negative cable first, that way when you bang your wrench up against the body of the car, also negatively charged, you don't weld the wrench to the body of the car.

If you don't already have at least one flat braided copper grounding strap connecting the engine to the firewall, I would add one pronto. I don't know if you are running an automatic trans or not, but if you are and you don't have a ground strap to the firewall, the grounding current will flow through the trans selector cable to ground (assuming that you have console shift). I know it sounds crazy, but I've replaced shifter cables on several Camaros and Monte Carlos because of that very problem. The shifter at first gets a little stiff and then all of a sudden you can't move it at all; it usually sticks in D and you don't find out until you get where you're going and can't move the stick when you stop. Like I've said, I wouldn't believe it was possible unless I had seen for myself the corroded shifter cables that came out of the cars. In every instance, the ground strap was either missing, unscrewed, or not making good contact with the firewall. If you do put a ground strap on your car, be sure to put an external tooth star washer under it so it will bite into the sheetmetal of the firewall when you tighten it down. As for your sparking bolts, I've never heard of that before, but I agree that you should remove the negative lead to the battery so you can't complete a circuit to ground.

Randy

You have definatlely got an power drain on that car,,,some thing is drawing power for it to spark that much.
And you can never go wrong by adding more grounds to your car.