The continuing saga of the oil pressure sending unit

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SirRobyn0

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Oh boy, I if you feel like reading a story this'll be a good one for you. So I've changed lots oil pressure sending units on small blocks, just did one on a customers 77 C20 a couple weeks ago. I know the issues and complications that can occur. So my truck has been pegging the oil pressure gauge since the middle of last week. My last day of work last week was Thursday and I'm due back on Monday. This time of year in the spring it is so busy at the farm. But I figured in 3 days I'd find the time. I set aside about an hour this morning (Sunday) so if I had trouble getting the sending unit out of the brass extension, I would have the time to free it up. Well of course it was stuck in there like nothing else, the brass wants to swivel in the block port, but the sending unit won't break free from the brass elbow. Ok I go get a wrench to fit the brass block and climb back up in there. Let me tell you it ain't getting any easier for me to crawl my fat ass up there like that with my knees perched on that little metal lip by the radiator, you know what I mean? So I get my fat ass up in there again..... I get my wrenches on and start getting a good push, pull on them, when I slip. Not the wrenches but my body. I let go of the wrench on the brass block and slam the wrench on the sending unit towards the firewall, thus slamming it into the distributor, resulting in a crack in the cap and of course breaking the brass fitting off flush with the block. Though, I'll consider myself lucky in the respect that I did not injure myself at all.

So I walk up from the barn and get into the Dakota, which after having not been started for a few weeks rewards me with a click when I try to crank it over. Walk back down to the barn return with jump box..... Dakota starts I head off to the shop which is almost an hour away to get my extractor sets, and buy some brass fittings, new cap ect. All told I'm gone nearly 2 1/2 hours. Of course I've got farm stuff todo today so I go about doing some of that stuff when I get back. About mid-afternoon I take the time to start trying to extract the brass bit. I heat the block up a little in that area and drive the extractor in. Just then my phone rings, it's my farm helper. There is a goose with a head injury and dead chicken can I come over to the coops to help sort it out. Well that was it, I never got back to the square. I really hate having it disabled, but that's just the way it is right now. I'll post what happens when I get to really try to extract that brass bit.
 

idahovette

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@SirRobyn0 I like this only for the written essay, I'd give you an A on it!!!The down side is , I feel your pain, both figurativley(SP) and physically!!! Something that should be a fairly easy operation and I can totally screw it up!!! Good luck at work today(Monday)!!
 

SirRobyn0

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@SirRobyn0 I like this only for the written essay, I'd give you an A on it!!!The down side is , I feel your pain, both figurativley(SP) and physically!!! Something that should be a fairly easy operation and I can totally screw it up!!! Good luck at work today(Monday)!!

I guess it just kind of makes me feel a little better to share the story. Also I don't know if you have ever read any Patrick f. McManus books, but part way through my writting I though gee this could be one of his stories with all comedy off errors going on. Well he would never say fat ass in one of his stories though, he always kept it clean at least as far as I can remember.
 

Matt69olds

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My buddy buys this van, notices the oil pressure gauge bounces wildly. Removes the engine cover, the sending unit is also hemorrhaging oil. He goes to remove the sending unit, promptly cracks the brass nipple off in the block. He tries to use a easy out to remove the remains of the nipple, not only does the brass fitting refuse to come out, the easy out cracks the block where the brass nipple threads in. Crap!!

Somewhere, there is a mid80s Chevy van with a cracked block, sealed up with JB weld, and the sending unit moved down by the oil filter.

It ain’t broke if you can fix it with JB weld!!
 

AuroraGirl

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My buddy buys this van, notices the oil pressure gauge bounces wildly. Removes the engine cover, the sending unit is also hemorrhaging oil. He goes to remove the sending unit, promptly cracks the brass nipple off in the block. He tries to use a easy out to remove the remains of the nipple, not only does the brass fitting refuse to come out, the easy out cracks the block where the brass nipple threads in. Crap!!

Somewhere, there is a mid80s Chevy van with a cracked block, sealed up with JB weld, and the sending unit moved down by the oil filter.

It ain’t broke if you can fix it with JB weld!!
Their plastic weld is no joke, some accidentally (mind you it wasn’t properly mixed either, so wtf) hit a tap and stuck it to my wooden bench. I could cut it out with a razor, I had to chisel it out. Wood to metal,

PLASTIC WELD.
 

SirRobyn0

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My buddy buys this van, notices the oil pressure gauge bounces wildly. Removes the engine cover, the sending unit is also hemorrhaging oil. He goes to remove the sending unit, promptly cracks the brass nipple off in the block. He tries to use a easy out to remove the remains of the nipple, not only does the brass fitting refuse to come out, the easy out cracks the block where the brass nipple threads in. Crap!!

Somewhere, there is a mid80s Chevy van with a cracked block, sealed up with JB weld, and the sending unit moved down by the oil filter.

It ain’t broke if you can fix it with JB weld!!

Yea, so an update. I managed to eek out a few minutes this morning to go at it again. I don't know how most guys go about extracting this sort of thing, but I've had good luck with heating the area a little, and very carefully with a propane torch, then using a one of those square extractors. I'm not sure what the technical name is for them but instead of having a twist to them like an easy out, they are just square and tapered. You hammer it into the brass and then turn it out. This went just as good as I could have hoped, heated it, hammered in the extractor and turned it out.

Matt, One time a few years back I blew the oil pressure sending unit in my Dakota, late at night about 100 miles from home. The top and bottom had separated. I cleaned the bottom of the sending unit hole as best I could filled with JB weld, (had the quick dry stuff in my tool box) and drove home. I changed to sending unit out right after that, but JB weld is sure good stuff!
 

SirRobyn0

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Got the new one installed this evening after flushing any possible debris out the oil hole. The only thing I don't like is the new brass extension and elbow are much thinner than the original stuff. I don't think there is much risk of it breaking off on it's own, but I think it increases the risk of complications next time.
 
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Oh boy, I if you feel like reading a story this'll be a good one for you. So I've changed lots oil pressure sending units on small blocks, just did one on a customers 77 C20 a couple weeks ago. I know the issues and complications that can occur. So my truck has been pegging the oil pressure gauge since the middle of last week. My last day of work last week was Thursday and I'm due back on Monday. This time of year in the spring it is so busy at the farm. But I figured in 3 days I'd find the time. I set aside about an hour this morning (Sunday) so if I had trouble getting the sending unit out of the brass extension, I would have the time to free it up. Well of course it was stuck in there like nothing else, the brass wants to swivel in the block port, but the sending unit won't break free from the brass elbow. Ok I go get a wrench to fit the brass block and climb back up in there. Let me tell you it ain't getting any easier for me to crawl my fat ass up there like that with my knees perched on that little metal lip by the radiator, you know what I mean? So I get my fat ass up in there again..... I get my wrenches on and start getting a good push, pull on them, when I slip. Not the wrenches but my body. I let go of the wrench on the brass block and slam the wrench on the sending unit towards the firewall, thus slamming it into the distributor, resulting in a crack in the cap and of course breaking the brass fitting off flush with the block. Though, I'll consider myself lucky in the respect that I did not injure myself at all.

So I walk up from the barn and get into the Dakota, which after having not been started for a few weeks rewards me with a click when I try to crank it over. Walk back down to the barn return with jump box..... Dakota starts I head off to the shop which is almost an hour away to get my extractor sets, and buy some brass fittings, new cap ect. All told I'm gone nearly 2 1/2 hours. Of course I've got farm stuff todo today so I go about doing some of that stuff when I get back. About mid-afternoon I take the time to start trying to extract the brass bit. I heat the block up a little in that area and drive the extractor in. Just then my phone rings, it's my farm helper. There is a goose with a head injury and dead chicken can I come over to the coops to help sort it out. Well that was it, I never got back to the square. I really hate having it disabled, but that's just the way it is right now. I'll post what happens when I get to really try to extract that brass bit.
Hope you are all right, glad to hear I am not alone in the pain club. I kinda solved the “laying on too the engine” problem by stuffing about a dozen old moving pads around the engine so as to make a flat surface to lay on. Darned near can fall asleep in there now.

Bottom line is, my sending unit came out just fine.. even with cruise control crap back there.
 

SirRobyn0

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Location
In the woods in Western Washington
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Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
Hope you are all right, glad to hear I am not alone in the pain club. I kinda solved the “laying on too the engine” problem by stuffing about a dozen old moving pads around the engine so as to make a flat surface to lay on. Darned near can fall asleep in there now.

Bottom line is, my sending unit came out just fine.. even with cruise control crap back there.
I've done sending units that came right out and mine shouldn't have been so much trouble, I kind of made that for myself. There use to be a guy at the shop that had a topside creeper, which could come in handy. Luckily I survived that incident just fine. I've got a few health issues, and I'm a bit over weight, so it's hard for me to breath laying on my belly for more than a few minutes, though a change in medication has helped a bit since then. Oh, and the oil pressure sending unit has been fine since then, but I do need a new oil pressure gauge now.
 

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