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studabaker

Supporting Member
207
2
Nov 1, 2008
Sacramento, California
So i attempted to rebuild my fwd 96 but it is leaking out of the oil sensor and i am not sure why or how to repair it. I had the crank polished and new main bearings oversized. I should be able to run with more pressure i guess is the problem. It seems to be flowing oil through properly. Is there anyone in the Sacramento area who might be able to look at it? Or anyone with any advice on how to go about repair. I have tried to plug the oil sensor port but it wouldnt start. So i need to short the sensor or get an entire computer or some kind of dsmlink computer or something?
Thank you for being here to help.
Stuart
 
is it leaking from the actual sensor or the port the sensor screws into?



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is it leaking from the actual sensor or the port the sensor screws into?



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He has a 420a it looks like. The question still remains valid, tho the locations provided don't relate.

I doubt the port is cracked, being cast iron, so I'm betting the sensor is leaking or the threads aren't sealed properly. Was the sensor replaced during the rebuild?
Having the crank polished etc doesn't affect how much pressure you can run, it depends on bearing clearances and oil pump quality.

I'd get a new sensor to install, and use proper sealer on the threads. I use PTFE thread tape for oil sensors personally.
 
Last edited:
Thank you for the replies. It is from the sensor out the electrical connector. I have read that once this occurs the sensor is "popped" and needs to be replaced which ive done twice. I appreciate the suggestion that its the threads because i wish it was. Not being the threads suggests i have excessive oil pressure for some reason. The oil is coming out the actual electrical connection because its dry at the threads. No hurry it has been sitting a while and i have resolved the main seal oil leak but dont want to take it apart again because that will be 3 times. I want to just run it and maybe it would get hot and resolve itself but it runs rough. I thought it was timing but now it just wont start. I think i got the timing right. I have to make sure i have good fuel at this point its been sitting at least 6 months now. I get busy but im ready now to finish it.

Thank you
 
Thank you for the replies. It is from the sensor out the electrical connector. I have read that once this occurs the sensor is "popped" and needs to be replaced which ive done twice. I appreciate the suggestion that its the threads because i wish it was. Not being the threads suggests i have excessive oil pressure for some reason. The oil is coming out the actual electrical connection because its dry at the threads. No hurry it has been sitting a while and i have resolved the main seal oil leak but dont want to take it apart again because that will be 3 times. I want to just run it and maybe it would get hot and resolve itself but it runs rough. I thought it was timing but now it just wont start. I think i got the timing right. I have to make sure i have good fuel at this point its been sitting at least 6 months now. I get busy but im ready now to finish it.

Im thinking i will put an oil pressure sensor after market in addition to stock and see where its at.

Thank you
 
I had a hairline crack in one of my OFH's that I had to have tig welded up so don't overtighten either of the sensors. Use tape and or thread sealant of some type as suggested and don't bottom out the sensor, that's what the original owner of my car did and that cracked the housing.
Just a tip on top of what the other guys have mentioned.
 
True you don't want to over tighten the sensor but I'd be impressed if you cracked the sensor port before ruining the sensor on a 420a. That spot is pretty beefy.

An aftermarket gauge would be good to see if you have insanely high oil pressure. It'd have to be quite high (100+ psi) to just blow through sensor diaphragms.

What weight oil are you running?
 
it would have to be one cheap ass sensor to be leaking from the inner part.
If your leaking problem is because of excessive oil pressure, your oil pressure relief valve may be stuck. To check it you would have to remove the timing belt stuff and then remove the plug with a hex head on top of the oil pump
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----------------------------------------------------

i guess you could bypass the oil pressure switch. pull the sensor and clean it up good, spray brake parts cleaner in the for the electrical connector and then fill it up with JB weld or something so i doesn't leak.
reinstall it with thread sealant or teflon tape. then cut the plug off the wire and attach the wire to a grounding point.
 
Man, I completely missed the 420 OFH part.
My bad.
These guys are correct!
 
Dusty,
That is the part of the system that I needed i formation on... It is true that as I look back that you have also answered this in my other thread. You replied the same day as well. I appreciate your timely response and your wisdom. Im not sure how a spring goes bad but it could be fixed closed and it makes sense that this would relieve the pressure by recirculating at a given spring rate. That is the exact thing i need it to do. I pull the sensor and the thread are dry and the inside of the electrical connection has oil in it. It did over tighten it at first but not enough to break the housing. It hits te back before being threaded completely on. I backed it off a few turns last time. The oil filter housing is certainly where I am going to focus my time for now. I apprsciate the image generation with the arrow to the relief valve. This was very helpful. That is worth some money if this turns out to be the issue and because I made a second thread I will be sure to become a supporting member. I had not read that and I am not intentionally making new threads on the same issue for fun. This will likely take some time but I will report back when its resolved.
 
Always like an ending to the thread so that it isn't open ended for the next searcher!
Thanks @studabaker !
Please let us know how it gets resolved :thumb:
 
you may have answered this already but i don't wanna go back and read a bunch of stuff.
so did you ever spin a bearing and that is why you had the crank work and new bearings put in?
If you did spin a bearing or had damage that caused the oil to be full of metal, did you reuse the oil pump that was on when the damage occured? I always replace the oil pump on a rebuild of an engine that had metal debris going thru the oil pump just to be safe.
If you did reuse the oil pump, the metal that went thru it may have siezed the piston for the relief valve.

With the motor installed you should be able to remove the plug for the relief valve by removing the alternator and the lower bracket where the alt. mount but i don't know if you'll be able to inspect the relief valve and you for sure can't check the clearances on the rotors n stuff

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====================================================

as far as the oil pressure switch (aka sensor), the thing has tapered threads so it doesn't thread in completely. only about 2/3 of the threads. its best to torque it down to spec.

in this pic, you can see how far it threads in by the bare threads
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Incredible amount of knowledge. The images are very helpful. I have my other car that i am working on as well. I got into doing my own work from this site. After i bottomed out and clipped the drain plug on the ground and leaked all my oil iut on the freeway. As soon a i heard a bad noise i shut it off. I knew i hit the ground hard but it was dark and i did not see the leak. I was hoping that i could get away with some of the old parts such as the oil pump hiwever i did not even know how to verify its condition. Maybe i should just put a new one on because if it is jammed i am not sure how i am going to remove the part that is apparently stuck closed. Its worth a try and i think the oil pump is at least pushing oil good and strong. That sensor it ths most annoying to get at and get tight so it would be hard to over torque it, or get a torque wrench on it... i guess a deep socket. I do things a lot better these days than when i started. I dont want metal in the rebuild so i should do the oil pump. Great. I spun bearing but after i lost all the oil so maybe it did not circulate. I will attempt to open the valve.

Thank you for the detailed image you generated.

Studabaker
 
I was able to acess it and remove the bolt. The spring came out easy but the rest I am not sure how to remove or service. I guess if it had come out easy then it would not be the problem. I used a magnet grabber thing. That is not very srtong but maybe i need to use some kind of pliers. Needle nose bent ones. I am not able to upload the picture i took from my phone. The does appear to be sides to grab it but if its siezed in place locking it closed then it will not be easy to remove. That is kind of good news in that i may have found an area malfunction, causing my oil pressure. Still in order to service it i need to remove it and clean it. The cap was on there really good. I used two extension breaker bars and a third breaker bar to rotate the 5/8 socket from above the engine. I put some weight into it. It could be damaged from heat. There was oil in the area that was clean of metal and the new synthetic i just put in.

How do i get that piston thing out now?

Stuart
 
1. Try a stronger magnet
or
2. get a piece of 1/2" O.D. aluminum tubing. Steel will work too but aluminum is easier to work with. cut it to the length you need., probably about 6-7" make sure one end stays perfectly round and the tube is straight for about 5" . That end will be going into the valve.

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make a mark about 3/4" from the end Now you need a hammer and a nail or center punch. you need to support it so the at the end isn't touching anythingl If you were to center punch it while it was flat on the floor the end would get deformed and wouldn't go in. As long as it stays perfectly round it will go in without any problem.

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So now your gonna center punch it half way between the make you made and the end. Make sure you don't punch it too hard. You can always do it again if the tube doesn't deform enough, Then center punch it again opposite of where you just did (180 degrees).
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If done right, the tip will be round and where you center punched it will be slightly out of round. Then when you insert the tube into the vavle chamber, the end of the pipe will go into the valve a little ways without resistance. if you look at the pic below. the tube only went in easily a little bit. When you get to this point, tap the tube a few times. the deformed part of the tube will wedge in the valve and you can pull it out.. Don't knock the shit out of it or any thing.. If for some reason it doesn't wedge in and pull out, its not out of round enough so you will need to lightly center punch it the tube and try it again.
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Does that all make sense?
 
Wow. Thanks for not ridiculing my incompetence. It makes sense. I wish i could upload my image. I will try on my pc in the am. I think the concept is effective though maybe not exactly what is in my vehivle. There is no inner circle just two sidecropped from the cylinder. I will try to get it to budge. Then it should lift with the grabber magnet
 
yours is different?
this thing is the relief valve out of an eclipse 420a oil pump.
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okay so my way complicated way to get it out, i guess could be used if its stuck in there. I ended up pulling out an old block with the oil pump on it. As soon as i took the cap off, instinct kicked in. For me, it goes something like " oh shit, its a hole, stick your finger in it"
which of course was the right thing to do..

here watch this 5 second video. It came out easy as f-u-c-k with just my finger.
https://streamable.com/uge1e
 
My friend it was the craziest thing. I was pointing with the magnet to a friend and it pucked up. Slipped right through. This prv appears to be functional. I am getting pressure above the pump then... your work up is very much appreciated. I assumed it was staying closed and was really hoping this was it. Back to square one.
 
I tried again and I was able to get the valve with the magnet. I was pointing out the problem to a friend and it picked up. I was really expecting it to be in there blocking oil flow. It appears to be functioning. I will replace everything and try to start her up. I hope this was not letting oil flow for some reason. This makes sense for my issue of excessive oil pressure. My valve is as pictured above. It looked different when it was inside.
 
Well if the relief valve is operating properly then your problem is not your oil pressure, its the switch.
 
I have the plug and know I just need to ground the sensor but that does not seem like a god idea. I did poke it a bit maybe it was jammed. I will try to start her again and see if anything has changed. i am really glad to have been able to learn this stuff, thank you. Give me a week.
 
I got it to run over and i keep throwing the ac belt off. I will mess with that a little more but Im afraid the head gasket is messed up. It appears to be blocking oil at that point. I need to replace the oil pressure sensor to see but it is coming out of there pretty good. I dont think i resolved anything and getting the ac belt to stay on is a small issue compared to this oil pressure thing. At least the head gasket is easy to get to. Just a lot of stuff to do. I appreciate the effort you put in rusty.
 
if you want to add a oil pressure gauge here is what you need

(1) 3/8" to 3/8" NPT Male Thread Brass Straight Hex Nipple
(1) 3/8 Female Tee
(1) 3/8 male x 1/8 female NPT reducer
(1) small tube of loctite 567


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