Hey guys,
you all know I bought this crate engine from GM, Ac Delco crate L98 matching sure enough I get it all in installed to find out the knock sensor hole is too big for the sensor.
So I call GM and they dont know what to do about it, very nice.
Seems like its nothing like a L98, more like a fuel injected 350 from a truck.
Seems like I have to heli coil this knock sensor, for $200 a kit, such a dissapointment but before that I will have to argue this with GM.
About the water pump, is there a plug on the top or a hose that it connects to?
I returned my core with it and I dont recall what was on there.

 

Heli-coil the knock sensor? If the hole's too big, buying a Heli-Coil kit for it seems like a rather nasty way of fixing it (#1 it's pricey and #2- helicoils don't like to have the fastener removed and reinstalled often- likely if you have to remove the sensor someday you'll have to heli-coil it again. That being said- it seems likely that some knock sensor or other should fit in the hole- the question is from which vehicle, and will the sensor be compatible with your harness plug and ECM?

 

I know, I thought it might require the 90-92 sensor but I was told they are the same size, so count that out.
I really couldnt say but coming from GM with them not knowing or helping really pisses me off after spending the extra $$$ to get something reliable and have a major issue like this.
They couldnt help in anyway which was dissapointing on their behalf.
if this was just some rebuild place I could understand but not when you buy a crate from GM that matches 87-89 L98.
I couldve been driving the car tonite

 

Just get an apapter plug and screw the knock sensor into that, and then screw that into the hole. Easy fix. Thats what I have with half of my sensor in the block I'm using now.

 

Where do I get one then and what size did you use?

 

Go to a parts store other than Canadian Tire and bring the sensor with you. Try to find a bolt that fits into the hole in the block and bring that as well.

 

I'd still try and find the correct-fitting knock sensor (if you think the crate was intended for a truck- go ask about a truck- like a '95 1500 or something). Using an adapter on this particular piece may cause issues- the sensor is designed for vibrations at a given frequency and putting it inside an adapter may be problematic. Hey- try it, but if things don't go quite right- be prepared.

 

As long as he finds an adapter that has a tight fit, so the knock sensor doesn't vibrate inside the adapter, he shouldn't have a problem.

 

Knock sensors have NPT threads, as do the block drain plaug holes they thread into.
Are you thrying to thread your old sensor into the right place?

By adapter, Dave means something like 1/2" NPT male (outside threads like a dick) x 3/8" NPT female (like soemthing else). This is a PIPE fitting, it will have one end with wrench flats on it.
Try to get a steel one, brass is your second choice.

Go to a fastener store and get the proper size you need.
Take a look at this attachment to get an idea of the right size.

Also, you need the knock sensor for your engine. Something from another GM might not work, IE V6 or 4cyl. Get one for the L98 and use that to be sure.