Need to add knock sensors to S3 block
#16
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Thread Starter
According to my 928Motorsports thread gauge... M14 1.5 thread pitch.
#17
RL Community Team
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Here's one - M14x1.5 with an M8x1.0 threaded center section for the knock sensor bolt. Not as long as the one you removed, but I'm not sure it matters. The sensor sits up on top anyway and is just sensing for knock.
https://www.ebay.com/i/163605423926?chn=ps
Here's another one -
What do you think?
https://www.ebay.com/i/163605423926?chn=ps
Here's another one -
https://www.amazon.com/Metric-Fitting-Adapter-M14X1-5-M8X1-0/dp/B07NHR29TK/ref=sr_1_fkmrnull_1?keywords=Metric+Fitting+Adapter+M14X1.5+M14+Male+to+M8+M8X1+M8X1.0+Female&qid=1557754840&s=gateway&sr=8-1-fkmrnull
What do you think?
#18
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Kind of end up with the bolt head below the deck so still faced with getting a socket on it. A bunch of spacers would be needed. I'm thinking about a long bolt to tap.
We could reach out to Carl, the collector of trashed blocks, for the proper bolt with the M8 thread in it. :-)
I know he has one of my 87 blocks.
We could reach out to Carl, the collector of trashed blocks, for the proper bolt with the M8 thread in it. :-)
I know he has one of my 87 blocks.
#19
RL Community Team
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Kind of end up with the bolt head below the deck so still faced with getting a socket on it. A bunch of spacers would be needed. I'm thinking about a long bolt to tap.
We could reach out to Carl, the collector of trashed blocks, for the proper bolt with the M8 thread in it. :-)
I know he has one of my 87 blocks.
We could reach out to Carl, the collector of trashed blocks, for the proper bolt with the M8 thread in it. :-)
I know he has one of my 87 blocks.
#20
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The problem as I see it is that pressure inside the block will want to push oil out the threaded insert. The M8 bolt holding the knock sensor will not be sufficient to seal the block from oil seepage. Oil in the valley is what I see.
#21
RL Community Team
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I'll let you know how it works out. I'm going to put sealant on the plug threads and the bolt threads which I think will take care of that. The pictures you posted of the threads you removed looks like they have sealant on them as well. I don't think the center threaded bolt will be more prone to leaking than the threads on the M14 plug.
#22
Keep in mind that the knock sensor is a microphone of sorts. It's designed to pick up the knock vibration. Length of thread engagement is important, as well as not using a sealant. Find a fitting as long as the original. and either drill and tap it. Isolating the sensor with any type of thread sealant is the equivalent of wrapping the sensor in a shop rag and tossing it in the valley.
#23
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Thread Starter
Keep in mind that the knock sensor is a microphone of sorts. It's designed to pick up the knock vibration. Length of thread engagement is important, as well as not using a sealant. Find a fitting as long as the original. and either drill and tap it. Isolating the sensor with any type of thread sealant is the equivalent of wrapping the sensor in a shop rag and tossing it in the valley.
#24
#25
RL Community Team
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Good point guys.
What are your thoughts on using copper or aluminum crush washers instead. They shouldn't quell the vibrations we're trying to pick-up, correct? How are the current valley plugs sealed to prevent leakage - or is that why there's often oil in the valley of many motors?
What are your thoughts on using copper or aluminum crush washers instead. They shouldn't quell the vibrations we're trying to pick-up, correct? How are the current valley plugs sealed to prevent leakage - or is that why there's often oil in the valley of many motors?
#26
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Thread Starter
Here's the proper bolt in situ:
I'll poach these while I source their replacement. sometimes, it's good to be a hoarder.
I'll poach these while I source their replacement. sometimes, it's good to be a hoarder.
#27
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Thread Starter
Out.
#28
RL Community Team
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#29
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Loctite. And your best source for the knock sensor bolts is Carl. He gets them from 928Int'l.
#30
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Thread Starter
Knock sensor bolts now in the upper block of my future stroker.