Oil Pressure Sender
Thread Starter
Instructor
Joined: Aug 2017
Posts: 216
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From: MD
Oil Pressure Sender
Hello
I have a new engine installed in my 1977 its GM 350/290 HP. I am using a temporary bolt in the hole on the top of the block close to the distributor. Will this oil pressure work? (PS157).
https://www.summitracing.com/parts/s...model/corvette
Other info I did used a smaller and skinnier oil pressure sender on the side of the block close to the oil filter but it seams it doesn't work?
I am seeing under 80 in my original gauge but when I used the a mechanical gauge it gave me 45.
I have a new engine installed in my 1977 its GM 350/290 HP. I am using a temporary bolt in the hole on the top of the block close to the distributor. Will this oil pressure work? (PS157).
https://www.summitracing.com/parts/s...model/corvette
Other info I did used a smaller and skinnier oil pressure sender on the side of the block close to the oil filter but it seams it doesn't work?
I am seeing under 80 in my original gauge but when I used the a mechanical gauge it gave me 45.
Last edited by ariba; Apr 22, 2018 at 04:19 PM.
Racer
Joined: Jan 2014
Posts: 407
Likes: 14
From: Mulberry Florida
Hello
I have a new engine installed in my 1977 its GM 350/290 HP. I am using a temporary bolt in the hole on the top of the block close to the distributor. Will this oil pressure work? (PS157).
https://www.summitracing.com/parts/s...model/corvette
Other info I did used a smaller and skinnier oil pressure sender on the side of the block close to the oil filter but it seams it doesn't work?
I have a new engine installed in my 1977 its GM 350/290 HP. I am using a temporary bolt in the hole on the top of the block close to the distributor. Will this oil pressure work? (PS157).
https://www.summitracing.com/parts/s...model/corvette
Other info I did used a smaller and skinnier oil pressure sender on the side of the block close to the oil filter but it seams it doesn't work?
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Either one of those ports will work regardless if you are using electrical or mechanical gauges. And you can use either copper tubing or plastic tubing.
If neither port gives you a reading, I would suspect the gauge or oil line is at fault. Always a slim possibilty that both ports got blocked with crud during the rebuilding of the shortblock. Compressed air can help you determine if there is a blockage somewhere.
If neither port gives you a reading, I would suspect the gauge or oil line is at fault. Always a slim possibilty that both ports got blocked with crud during the rebuilding of the shortblock. Compressed air can help you determine if there is a blockage somewhere.
Last edited by HeadsU.P.; Apr 28, 2018 at 08:16 AM.
Thread Starter
Instructor
Joined: Aug 2017
Posts: 216
Likes: 10
From: MD
Either one of those ports will work regardless if you are using electrical or mechanical gauges. And you can use either copper tubing or plastic line.
If neither port gives you a reading, I would suspect the gauge or oil line is at fault. Always a slim possibilty that both ports got blocked with crud during the rebuilding of the shortblock. Compressed air can help you determine if there is a blockage somewhere.
If neither port gives you a reading, I would suspect the gauge or oil line is at fault. Always a slim possibilty that both ports got blocked with crud during the rebuilding of the shortblock. Compressed air can help you determine if there is a blockage somewhere.
Thanks
Thread Starter
Instructor
Joined: Aug 2017
Posts: 216
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From: MD
Update
I found out the old dumb shop put the wrong bolt in the hole on the top of the block close to the distributor, When I toke it off and wanted put the new oil sensor it didn't fit because the temporary wrong bolt changed the tread of the hole.
It heart to see that in a Brand New Engine.
Any Suggestions?
I found out the old dumb shop put the wrong bolt in the hole on the top of the block close to the distributor, When I toke it off and wanted put the new oil sensor it didn't fit because the temporary wrong bolt changed the tread of the hole.
It heart to see that in a Brand New Engine.
Any Suggestions?
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Man, that sucks. They must have put a std thread bolt in a NPT hole. Not exactly a good place to drill it out with the shavings and tight spaces either. If that port next to the dizzy doesn't leak, then leave it alone for now.
Using the port above the oil filter is your only option. Remove the sending unit and spray a little degreaser in there. Must be plugged or you have the wrong sending unit.
Using the port above the oil filter is your only option. Remove the sending unit and spray a little degreaser in there. Must be plugged or you have the wrong sending unit.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
I have had this happen when a person...not a shop... did the same thing. I used my pipe tap and threaded it so the sender could be installed.
As for the shavings. I took the power wire to the ignition coil off so when I spin the engine it would not crank up. I them took a towel and put it over the hole and had a friend spin the engine and it flushed out the remaining fine shavings....because ...honestly ...where else are they going to go.
And YES...I also did the tapping of the hole SLOWLY and put grease on the tap to grab what I could and vacuumed out the hole prior to flushing it out. Then it was doing a little bit of clean up and adding oil back to the engine.
DUB
As for the shavings. I took the power wire to the ignition coil off so when I spin the engine it would not crank up. I them took a towel and put it over the hole and had a friend spin the engine and it flushed out the remaining fine shavings....because ...honestly ...where else are they going to go.
And YES...I also did the tapping of the hole SLOWLY and put grease on the tap to grab what I could and vacuumed out the hole prior to flushing it out. Then it was doing a little bit of clean up and adding oil back to the engine.
DUB
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Thread Starter
Instructor
Joined: Aug 2017
Posts: 216
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From: MD
Man, that sucks. They must have put a std thread bolt in a NPT hole. Not exactly a good place to drill it out with the shavings and tight spaces either. If that port next to the dizzy doesn't leak, then leave it alone for now.
Using the port above the oil filter is your only option. Remove the sending unit and spray a little degreaser in there. Must be plugged or you have the wrong sending unit.
Using the port above the oil filter is your only option. Remove the sending unit and spray a little degreaser in there. Must be plugged or you have the wrong sending unit.
I returned the bolt and it doesn't leak
Thread Starter
Instructor
Joined: Aug 2017
Posts: 216
Likes: 10
From: MD
I have had this happen when a person...not a shop... did the same thing. I used my pipe tap and threaded it so the sender could be installed.
As for the shavings. I took the power wire to the ignition coil off so when I spin the engine it would not crank up. I them took a towel and put it over the hole and had a friend spin the engine and it flushed out the remaining fine shavings....because ...honestly ...where else are they going to go.
And YES...I also did the tapping of the hole SLOWLY and put grease on the tap to grab what I could and vacuumed out the hole prior to flushing it out. Then it was doing a little bit of clean up and adding oil back to the engine.
DUB
As for the shavings. I took the power wire to the ignition coil off so when I spin the engine it would not crank up. I them took a towel and put it over the hole and had a friend spin the engine and it flushed out the remaining fine shavings....because ...honestly ...where else are they going to go.
And YES...I also did the tapping of the hole SLOWLY and put grease on the tap to grab what I could and vacuumed out the hole prior to flushing it out. Then it was doing a little bit of clean up and adding oil back to the engine.
DUB
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
The oil pressure sender hole above the oil filer requires a special long brass fitting that can thread into the hole in the block due to being larger threads than the sender has. Then this fitting is reduced down to the threads so the sender can be threaded into it.
DUB
DUB
Racer
Joined: Mar 2018
Posts: 395
Likes: 52
From: wilmington Ma
The first thing reading this I was "oh no" someone ran a bolt in pipe threads 
pipe threads are cone shaped to seal , I would do like Dub says put grease on the tap I would also start the motor without the sender elbow or sender in and have the oil spary out in a rag to blow out any shavings. Not sure who put a bolt in there but I would definitely recheck all that mans work.
pipe threads are cone shaped to seal , I would do like Dub says put grease on the tap I would also start the motor without the sender elbow or sender in and have the oil spary out in a rag to blow out any shavings. Not sure who put a bolt in there but I would definitely recheck all that mans work.
Pro
Joined: Mar 2018
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From: Seattle WA
Last edited by Kie; Apr 23, 2018 at 10:19 PM.
Race Director
Joined: Apr 2009
Posts: 19,294
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From: Charlotte NC
On the oil port above the oil filter area. A brass 90 degree fitting will not work due to the recess in the casting of the block that would make this a BEAR. Using the correct straight fitting or making one up is best due to it brings that area outwards an allows the oil pressure sender to be easily attached.
DUB
DUB
Le Mans Master
Joined: Jan 2001
Posts: 6,743
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DUB, is this what you're describing? Just curious (since I have a 68). Anything special about this? Looks like something you could get at a hardware store?
replacement:
https://willcoxcorvette.com/corvette...to-block-74-79
reconditioned:
https://www.paragoncorvette.com/p-35...r-fitting.aspx
replacement:
https://willcoxcorvette.com/corvette...to-block-74-79
reconditioned:
https://www.paragoncorvette.com/p-35...r-fitting.aspx
On the oil port above the oil filter area. A brass 90 degree fitting will not work due to the recess in the casting of the block that would make this a BEAR. Using the correct straight fitting or making one up is best due to it brings that area outwards an allows the oil pressure sender to be easily attached.
DUB
DUB
Last edited by carriljc; Apr 24, 2018 at 11:34 AM.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
DUB, is this what you're describing? Just curious (since I have a 68). Anything special about this? Looks like something you could get at a hardware store?
replacement:
https://willcoxcorvette.com/corvette...to-block-74-79
reconditioned:
https://www.paragoncorvette.com/p-35...r-fitting.aspx
replacement:
https://willcoxcorvette.com/corvette...to-block-74-79
reconditioned:
https://www.paragoncorvette.com/p-35...r-fitting.aspx
Here are photos of an original I have below.
I know that other fittings can be used that may be able to be shorter...so the choice is up to the person doing the job.
DUB
Racer
Joined: Mar 2018
Posts: 395
Likes: 52
From: wilmington Ma
On the oil port above the oil filter area. A brass 90 degree fitting will not work due to the recess in the casting of the block that would make this a BEAR. Using the correct straight fitting or making one up is best due to it brings that area outwards an allows the oil pressure sender to be easily attached.
DUB
DUB