black7

iTrader: (1)

I bought a rebuilt short block from Xtreme Horsepower and was planning on assembling it this weekend. I came across a slight snag and was wondering what I can do about it.

So I was putting the knock sensors back on and one of them didn't seem to go in easily. The other one went right in with no resistance at all. So I take a flash light and look into the hole where the sensor screws into and it looks like one of the threads half way down is stripped.

I know the next step would be to contact Xtreme Horsepower, but being that it is the holiday weekend I won't be able to get a hold of them until next Tuesday. I was hoping to have the block completely re-assembled and ready to drop into my car by tomorrow. Besides the lost weekend, I would have to spend time to have it shipped back to them and for them to ship me a new short block (after I dis-assemble everything I've put back on already). So I'm hoping there's something I can do instead of going through all that hassle.

What can I do? Tap it? Is it safe? Is there a bigger sized knock sensor I can use if I can tap it?

Any help or advice at all would be greatly appreciated.

THANKS!!!!

black7

iTrader: (1)

Any help/suggestions/advice would be greatly appreciated.

Thanks!

matt94z

iTrader: (49)

try to find the right tap and chase the threads.

black7

iTrader: (1)

Thanks, I was thinking about doing that but wasn't sure if there was any other options. I was just worried as this is a sensor port which I didn't know if it was different than just an ordinary bolt port.

I guess I'll try and get a tap to run down there and hopefully clean up the threads a bit.

Any idea as to what the tap size is for this?

matt94z

iTrader: (49)

take your knock sensor to an auto parts store and hive them to check the thread pitch. They should be able to tell you what size tap you would need.

raven154

iTrader: (14)

If the threads are striped out then chasing the threads wont do any good. You best bet if the threads are gone is this. Go find a Heli-coil that fits the knock sensor. Drill and tap the block for the heli-coil and then screw the knock sensor back in. Permanent fix and your done. Just make sure you plug the holes in the valley and vacuum all the shavings out.

black7

iTrader: (1)

Thanks for all the suggestions so far. The threads weren't completely gone. Half way down they were pretty chewed up though. (about 5-6 threads down).

So I got the right sized tap and put it through a couple of times. It seems to have cleared it up SOME, but not completely. The sensor goes in now, but doesn't sit flush with the pedestal. It's just a tad bit off, but I can't screw it in any further. Is this going to be okay? or will it affect the sensitivity of the sensor?

FYI the tap size is 10x1.5

matt94z

iTrader: (49)

You are suppose to torque them to proper spec. Not sure if it will affect the sensitivity if it isn't though.

chevyguy7802

iTrader: (3)

+1 on the heli-coil

black7

iTrader: (1)

So I went to at Home Depot, OSH, Kragen, Pep Boys, Napa Auto, Ace Hardware, no one carries Heli Coils or any type of thread repair kits with inserts. The closest I've found was someone telling me to JB Weld the whole thing and re-tap it from there. I also found a kit that was similar to that made by Permatax where you fill the hole and re-tap it.

How can no hardware/automotive store carry Heli-Coils??

35th SS

iTrader: (2)

wow not even Napa carries the size.thats a surprise.