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Oil Sending Unit Leak/Spray

It'll be the front main seal leaking onto balancer and spraying only onto the sending unit somehow.
 
How exactly did you check the threads? Visually isn't going to cut it as you can't see if it is out of round, for example, by a millimeter or so which would allow a leak. Best to assemble outside the car and simply fill the tube with fluid and, holding it vertically, see if you get seepage at the sender connection.

Silicone sealers are not designed to be used as thread sealing medium. They are for static compression type sealing duty. Teflon tape is what you need to use. By far the best material for the job. It will seal up minimally distorted connections and less than perfect threads. Second best are liquid teflon sealers.

Are you one of those guys who thinks tight enough means one last hard pull on the wrench? Could be you cracked the extension metal. Hard to see except when torqued tight and caused to open. That would explain the "spray" type leak you are seeing.
 
I hear you and I have tried tape several times with varying layers of tape and differing thread engagements ...some more loose than others.

I inspected the threads as best I could with my calibrated naked eye. This is just a last ditch test prior to plugging the extension to test it alone, and then removing to assemble and bench test out of the car.
 
Would it be worth doing the trick you use for tires? Get a spray bottle with water and some dish soap, then spritz the area and look for bubbles. I wouldn't think it'd do any harm as the oil system is pressurized so its not going to suck the water in or allow it to seep in.

This just allows you to see where a leak is occurring, it won't fix it. Not sure if we're still thinking its the water pump or not.
 
Boom said:
Would it be worth doing the trick you use for tires? Get a spray bottle with water and some dish soap, then spritz the area and look for bubbles. I wouldn't think it'd do any harm as the oil system is pressurized so its not going to suck the water in or allow it to seep in.

This just allows you to see where a leak is occurring, it won't fix it. Not sure if we're still thinking its the water pump or not.
Click to expand...
Why not get an oil die that shows up with ultraviolet light to pinpoint where the leak is?
 
I can see where the leak is occurring. I have just been unsuccessful fixing the damn thing.

What I haven’t done is remove the extension and sender to see if in fact there is a crack when installed. I have been apprehensive in doing this...because it ISNT LEAKING AT THE DAMN BLOCK.

NOR IS IT THE DAMN WATER PUMP OR FRONT MAIN SEAL OR HEAD OR CRANK OR SHOCK OR REAR LEAF SPRING.
 
I get that are sure it is leaking where the sender screws into the extension. This is not rocket science so I feel your frustration. There can only be a couple things that cause it. Take the assembly off the engine and do a simple leak test as I suggested. That silicone is not fully set yet and the engine oil pressure will blow right past it if you have any gap from poorly cut threads or a crack.

Deep breath. You'll get through this. ;)

I know how you feel. I spent a LONG time chasing down a virtually indistinguishable leak in my brake system last year. Couldn't get a firm pedal but also couldn't find any fluid leak either. That was fun.
 
can you remove the extension and sender and adapt it up to compressed air and then use soapy water ir a bucket with water in it to see what is going on? using an air pressure regulator will allow you to being up the pressure at a rate you are comfortable with.
 
Yes and I intend to do so...if this doesn’t work. Even if it does work for a while and crops back up, I will be doing so.

Previous post was meant in humor...BTW. As I’m sure some of the continued repeat suggestions are.
 
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