Unknown fitting in block - Boost Forum

Forum Post / Reply
You must log in before you can post or reply to messages.
Unknown fitting in block
Thursday, April 14, 2005 11:09 AM
I have a new (surplus) turbo block for 2.0 (VIN code M) Sunbird. The block has what I can best describe as a thermowell in it. It is brass, it penetrates the block just above the bottom, it is "blind" and sticks into the block about a 1/4 to 1/2 inch. It has a rubber plug in it right now. There are no threads in it. It does not show in any of the diagrams in my factory service manual. Does anyone know what this is for?

Re: Unknown fitting in block
Thursday, April 14, 2005 12:12 PM
freeze plug?
Re: Unknown fitting in block
Thursday, April 14, 2005 12:29 PM
No, it's much smaller in diameter than a freeze plug. I'll post some pictures of it when I get home tonight
Re: Unknown fitting in block
Thursday, April 14, 2005 12:35 PM
coolant heater for cold climates ??


or oil drian back for the turbo ??






Re: Unknown fitting in block
Thursday, April 14, 2005 12:49 PM
I really appreciate the replies, but it's not any of those. The coolant drain back is on the same side, it's much bigger. Check in tonight after I've had a chance to upload some pictures. It's a blind fitting, appears to be pressed in. I've never seen anything like it. The closest thing I've ever seen is in industrial applications, they use a well for a temperature sensor so the sensor itself isn't exposed to either the fluid or fluid pressure. Not saying that's what this is because it doesn't make sense, there's nothing in the engine you wouldn't want to expose a sensor to. Maybe it's for oil temperature sensing,or maybe they just drilled a hole where it wasn't supposed to be and this is how they plugged it. I'll post some pics. Thanks, everyone.
Re: Unknown fitting in block
Thursday, April 14, 2005 5:00 PM
It sounds like its the hole for the block heater, how big is the diameter? The block heater on the 2.0s were tiny I pulled mine out and put in a small freeze plug when I rebuilt it.


<img src="http://www.geocities.com/fudd_22602/elmer-shoot.gif"> Old school Js rock
Re: Unknown fitting in block
Thursday, April 14, 2005 5:13 PM
The term "freeze plug" refers to a cup plug.
Cup plugs can be as small as 1/4" .
A 2.4 has 3/8" cup plugs on both sides of the cam carriers. ( I know your not talking about a 2.4, but pics of 2.4s are plentiful here)


sig not found
Re: Unknown fitting in block
Thursday, April 14, 2005 7:45 PM
Re: Unknown fitting in block
Thursday, April 14, 2005 7:46 PM
OK, click on the link for some pics of this fitting. I actually thought about a heater, but this doesn't go into the cooling water jacket at all. It penetrates through the wall of the block into the crankcase.
Re: Unknown fitting in block
Thursday, April 14, 2005 7:51 PM
lol, looks like a spot for a crank position sensor......



SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

Re: Unknown fitting in block
Thursday, April 14, 2005 7:56 PM
Naah, I have a '92 NA engine. The crankshaft position sensor is mounted above that location and is quite a bit bigger. The '92 engine does not have this plug. Also the CPS would not be a blind plug. This plug has no hole in it at all. It is probably about 3/8" in diameter and angles upward, not downward toward the crank. Turbo engines did not use DIS, so they wouldn't have had a CPS (I think).

Re: Unknown fitting in block
Thursday, April 14, 2005 8:05 PM
Honestly I think it may be a plug to cover a mistake...
Re: Unknown fitting in block
Thursday, April 14, 2005 8:08 PM
I've rebuilt this same engine before and I don't remember seeing any hole there, definitely not that sleeve hmmm The 2.0 turbos did have a knock sensor, I'm not sure where this is at. Are you sure its not the oil return line? The 2.0 turbo was both water-cooled and oil-cooled.


<img src="http://www.geocities.com/fudd_22602/elmer-shoot.gif"> Old school Js rock
Re: Unknown fitting in block
Thursday, April 14, 2005 8:43 PM
Looking at it again, I'm positive that's for the oil return line from the turbo.


<img src="http://www.geocities.com/fudd_22602/elmer-shoot.gif"> Old school Js rock
Re: Unknown fitting in block
Friday, April 15, 2005 4:55 AM
Yeah, I'm sure it's not the oil return line. Now that I know how to post photos, I'll get some more up this evening that show the whole block, including the return line port. Remember, this plug, or "sleeve" has no opening into the block. It's blind. The oil return port is about a 5/8" or 3/4" tapped opening, about in the middle of the block (middle from front to back). This is an unthreaded 3/8" hole plugged with a brass plug with no opening on the inside end. Weird.
Forum Post / Reply
You must log in before you can post or reply to messages.

 

Start New Topic Advanced Search