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Spark plug gap being closed in engine.

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Adgbiking

Probationary Member
5
0
Apr 5, 2008
Marshfield, Wisconsin
Hey Guys, I just pulled my spark plugs out today becaue my car was acting up and the middle two plugs are BEATEN UP! The electrodes and touching the spark plug. So that was my awnser to why my car was runing bad so i regaped them and put them back in. I drove down the road and same problem. So i come back and pull out the plugs again and they are the same way with the electrodes pushed in. So i thought WTF the piston has to be hittin it. So i threw one more spacer on them and it runs fine and there is no hitting. Like i said before it is only the two middle plugs and the end ones are just fine. Can anyone help me??? Is my motor going to blow soon? Thanks
 
Piston slap is an entirely different problem. The only thing I can think of is doing a compression check and see what numbers you are getting compared to the cylinders 4 and 1. There shouldnt be clearance issues at all.
 
Ok thanks guys, ya I was running bosch platinum 2's but when i spaced the plugs i used NGK V pwr. Could there be anyway that the crank or the internals of the motor are wore and making the pistons up up higher?
 
If you're crushing plug gaps, your motor is blown. And no, that's not what "piston slap" is. Piston slap is the skirts smacking the cylinder walls as the piston tries to rock in the bores.
 
BPR6ES = Stock temp NGK plugs
BPR7ES = 1 Range Colder (350+WHP) (Or E85 at any HIGH power level)
BPR8ES = 2 Ranges Colder (550+WHP)

These are the only plugs you should ever run on a DSM. If you are crushing these plugs inside the motor, you have serious motor problems.
 
if you're running ngk bpr6es plugs like you're suppose to then you're looking at a complete bottom end rebuild. if the piston is reaching far enough up the cylinder to touch the plugs you need to stop trying to drive it until you can get everything fixed. you might end up having to do a complete rebuild including the top end, but you cant know that until you or a shop gets in there and see's what kind of shape its in.

more than likely you've got main bearings in bad shape on the crankshaft. the bearings could be cupping and allowing the connecting rod, hence piston, to travel that few too many millimeters and touch the spark plug.
 
Look at his car. It's a non turbo 1G. He wouldn't be running the same kind of spark plugs as turbo guys............. So the spark plugs you are recommending him wouldn't be correct. Sounds to me he is running too lean somehow.
 
Look at his car. It's a non turbo 1G. He wouldn't be running the same kind of spark plugs as turbo guys............. So the spark plugs you are recommending him wouldn't be correct. Sounds to me he is running too lean somehow.

oops..... but the rest would still be the same for any engine.
 
Look at his car. It's a non turbo 1G. He wouldn't be running the same kind of spark plugs as turbo guys............. So the spark plugs you are recommending him wouldn't be correct. Sounds to me he is running too lean somehow.

That doesnt matter as everything is the same except for compression. I had a turbo NT block an it never had clearance issues. And running lean does not smack your plugs. Your really going to have to pull the oil pan off. Im betting those two bears probably took a beating and oval'ed it out. That is the only thing I can think of why the pistons are touching the plugs in 2 and 3.
 
Ok, thanks alot for the comments guys. So how much am i looking at if i do this myself? And is it s pretty hard task?
 
i know this is old, but wouldnt it be relativley easy to tell if the pistons were hitting the spark plugs? i would think there would be some loud clattering going along with the beat spark plugs.:confused:
 
Well I just read this thread myself and if you think about it, the plugs hes using would have to be really long and poking out into the cylinder for that to happen. Cause if not, the pistons would hit the cylinder head and valves before it would hit the spark plug.
 
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