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Paul Workman
11-15-2010, 05:58 AM
I spent over a year getting ready to "go play" at a recent Corvette Challenge race, only to have the cabin fill with smoke on the first run :mad:(a couple weeks ago).

According to the gurus, the (low) oil pressure switch - the one that is on the bottom side of the oil filter housing - has a propensity for leaking. And, it is very close to the #2 header pipe, I might add (hence the smoke!) At first I noticed an occasional whiff smell of burning oil. Then Marc Haibeck told me the car used about 3/4 quart of oil during the tuning process. This was followed by me then noticing the side of the car and passenger window covered with "freckles" of dust - which I dismissed as "musta got something sprayed on me while driving on the highway somewhere??" But, at WOT on the first pass, it blew big time!

Marc and I looked for the leak while at the track, but could not see anything for sure. After I removed the side wheel panel and put a light in there was I able to see the bottom of the pressure switch had been oozing oil and everything below it was oily. After removing the right-side motor mount nut and jacking the motor on it's side (a couple inches), I could clearly see the little bastard!

But, here's my point: Don't bother tying to get at the SOB directly. Take the 10-15 minutes it will require to remove the air cleaner, the belt and tensioner**, the oil cooling lines, and the 5 bolts holding the oil filter housing in place. You don't have to lift the filter housing out of the car, but you can now easily rotate it to expose the sensor. (I bought that special socket for removing such sensors, but a pair of Channel Locks would easily get to it now.) Put some sealant on the threads (I used Teflon tape) and turn it in to just snug enough to seal - "practically, just a little more than hand tight", according to Marc H. (The body of the sensor is pot metal and the threaded tip is only about 3/8" in diameter. If it snaps off, you'll have another interesting chore ahead of ya:censored::censored:)

Back together now, and all is well...No more "freckles" :mrgreen: Now, I think I need to move my rev limiter up a couple hundred rpm. With the "FBI" style of porting and mods (and the extra 130 hp to go with it), it is going to take some getting used to!

P.

**PS: If you've never removed the belt tensioner before, you might want to scratch or paint a line across the joint between the tensioner and the engine so you can align it properly on reassembly. Otherwise, it is possible to have it turned too far (clockwise) upon tightening and you'll not be able to get the belt on...trust me.

-=Jeff=-
11-15-2010, 09:12 AM
Great information.....as always you describe issues in perfect emotional and technical detail :thumbsup:

You can see the oil pressure switch below oil filter near bottom on oil filter housing.

http://i287.photobucket.com/albums/ll142/dynomite007/ZR1%20NET/Oilpressuresensorlocation.jpg

In Solutions under the Heading ENGINE LUBRICATION SYSTEM http://www.zr1.net/forum/showthread.php?p=88872&post88872

Is that it on the bottom left of the picture below where the oil cooler lines go?

Paul Workman
11-15-2010, 12:24 PM
Great information.....as always you describe issues in perfect emotional and technical detail :thumbsup:

You can see the oil pressure switch below oil filter near bottom on oil filter housing. It is on the bottom left of the picture below where the oil cooler lines are located.

http://i287.photobucket.com/albums/ll142/dynomite007/ZR1%20NET/Oilpressuresensorlocation.jpg

In Solutions under the Heading ENGINE LUBRICATION SYSTEM http://www.zr1.net/forum/showthread.php?p=88872&post88872

Actually, the SOB in question is hidden behind and to the side of the Oil Temp sender (bottom in the photo). The top sensor is the pressure sensor for the gauge, the one in question is the low pressure switch which turns on an IDIOT light on the dash, and I thought I read somewhere that if the low pressure switch is activated that the ECM shuts off fuel??? I dunno for sure 'bout the latter, how some ever.

I'll try to get my download to work and send a pic later today

P.

sammy
11-15-2010, 12:55 PM
is the sensor on the oilfilter housing.

Jagdpanzer
11-15-2010, 01:07 PM
Sorry guys, still not clear to me.
How about circling it to remove my confusion?

Paul Workman
11-15-2010, 02:36 PM
I think the oil pressure switch is A and the oil temperature sensor is B :D

I am guessing (you already know that) the oil pressure switch is threaded into the block and not the oil filter housing?

http://i287.photobucket.com/albums/ll142/dynomite007/ZR1%20NET/OilpressuresensorlocationA.jpg

A = correct; the pressure switch. However, you can't really see any more than just the lip of the connector housing in this photo. A picture taken from the side (right side of the engine) would be helpful (and if nobody has posted one by later today, I'll take a pic of mine as installed).

P.

Jagdpanzer
11-15-2010, 02:37 PM
Here is a better view of it

http://i540.photobucket.com/albums/gg333/pwasinger/HR-LT5028-1.jpg

Paul Workman
11-15-2010, 02:47 PM
is the sensor on the oilfilter housing.

Yes, on the right side of the engine, but attached to the oil filter housing. It is hard to see when the wheel panel is in place - tucked way down in there.

P.

bdw18_123
11-15-2010, 04:32 PM
Yes, on the right side of the engine, but attached to the oil filter housing. It is hard to see when the wheel panel is in place - tucked way down in there.

P.

Here is a picture of mine after I cleaned it. Added text and arrows for more clarity (and I'm definitely going to be resealing all the sensors!):

http://i13.photobucket.com/albums/a292/bdw18_123/STA70020-2.jpg

ittlfly
11-15-2010, 05:48 PM
P.

**PS: If you've never removed the belt tensioner before, you might want to scratch or paint a line across the joint between the tensioner and the engine so you can align it properly on reassembly. Otherwise, it is possible to have it turned too far (clockwise) upon tightening and you'll not be able to get the belt on...trust me.

Thanks Paul.......I wonder if that was my problem when I R&R'ed the tensioner and belt last year. I didn't mark the old tensioner as to its orientation to the block. In putting on the new one I could see that it could be installed wrong....even though it had a '' mounting tab'' on the back of it. I emailed Marc but he didn't think it would be possible as he never had a problem. The problem is that I"m a lot stupider than Marc and I had a hell of a time getting the belt over the last pully. I wrote it off as a ''tight belt'' . I hope I haven't screwed it up as it has been on the car that way for about a year now. :confused:

Paul Workman
11-15-2010, 07:53 PM
In putting on the new one I could see that it could be installed wrong....even though it had a '' mounting tab'' on the back of it.

...Which is exactly why I mentioned it. You can rotate it too far CW and the stop tab will find a hole and make you think all is well. Then you go to put the belt on and suddenly you find yourself doing :icon_scra a lot!! BTDT. However, there was NO WAY to get the belt to fit if the tensioner is "that way". So, I would guess if you got the belt to fit, you must be OK - especially if there is some reserve spring travel in the tensioner after you got the belt on.

Chit happens...Oh, how I know that!:mrgreen:

P.

Paul Workman
11-15-2010, 08:00 PM
I'm definitely going to be resealing all the sensors!



In my case, it wasn't the threads that were leaking, but rather the oil was blowing through from the inside of the connector, past the weather pack gasket to spray everything in the vicinity. It is a common problem, according to Marc H. But, I'd not seen a write up on it, and so I thought I would mention it in case someone else developed a "common problem" of their own!;)

Thanks for posting the picture tho. There you can plainly see the PS.

P.