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Old 03-21-2002, 02:15 AM   #1
neonlarry
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Post Oil Pressure ??

When I am on the freeway and I have to stop for traffic, right after I stop the oil pressure will go down to almost 0 for about 2 seconds, and them go back to normal. There is plenty of oil in it. Any ideas? I really don't have money for a new engine right now.
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Old 03-21-2002, 02:20 AM   #2
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does your engine rattle? after market guages are not super accurate at low end of scale. I have stewart warner and it goes to almost 0 when i tested it with a auto meter it showed 8-12 psi so if its not rattling dont worry

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Old 03-21-2002, 02:22 AM   #3
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it is the factory gauge, and yes, it sounds awful, that is the main reason i was asking about it.
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Old 03-21-2002, 02:33 AM   #4
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Wow. DON'T drive it until you get it figured out! It will wreck more stuff if you keep runnin' it. May need a new oil pump. Maybe the bearings are worn bad. It's cheaper to do a semi-rebuild (new bearings, oil pump), than to keep running it and break a connecting rod and have it poke a hole in the side of your block. Then you will be looking for a complete motor. Not just a rebuild.
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Old 03-21-2002, 02:40 AM   #5
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It only does it for a few seconds at a time, but it rattles really loud, and the gauge is almost to 0. So I should try replacing the oil pump? has anyone else had this problem? The truck didn't do it when I bought it, but after I put syntetic oil in was when I first noticed it. I have heard that with s/b chevys, sometimes the oil takes a long time to get back to the pan, but with 3.07 gears at 60mph, that shouldn't do that
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Old 03-21-2002, 02:41 AM   #6
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Dont drive drop the pan check screen, could also be bad main bearings that cause low pressure but if you continue to run it will only get worse Good Luck

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Old 03-21-2002, 02:42 AM   #7
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Would the weight of the oil make a difference? I don't remember what it is, but I can look tomorrow.
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Old 03-21-2002, 02:54 AM   #8
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You could run streight 30Wt in it (not 10-30 or 20-30, just plain SAE 30). Or even 50Wt. Thats just a band aid. It will die in short order if not fixed quickly. And if it ruins your block, you will wish you spent a little money now. Just my .02 Darren
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Old 03-21-2002, 02:59 AM   #9
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I will have to start saving my money I guess, It seems like we never get things fixed unill they are really broken, but this time I think we will have too. If anyone else has any suggestions I would like to hear them. I know I will probably have to have the engine rebuilt, but it would be nice if it was something I could fix myself
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Old 03-21-2002, 03:04 AM   #10
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Maybe (i'm guessing here) the best / quickest thing to do would be to run heavier oil for now. Buy some time. Maybe some other board members will have some suggestions tomorrow.
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Old 03-21-2002, 03:08 AM   #11
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thanks, I will check back tomorrow.
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Old 03-21-2002, 08:14 AM   #12
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have you had the oil pan off? when i pulled my oil pan i pushed up the pickup tube to get the pan off. then. (feels very dumb) forgot to put it back in the right position. had the exact same results as u describe...oh well sometimes u have to make the mistaked to learn
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Old 03-21-2002, 11:32 AM   #13
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As far as I know, the pan has never been off.
The truck did not have this problem whae I first bought it. I first noticed it after I changed to 10w40 oil. I will be sitting in traffic and the gauge will strrt to go down, and the enging will start rattleing and just when I think I thougd shut it off, the pressure will come back up and it will be fine. It was a little bit worse the last time it happened though. So do you thing oil pump problem, or is it time to re build the engine
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Old 03-21-2002, 11:46 AM   #14
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I would suggest doing a compression check and see what the condition of the motor seems to be.

I bought my 71 that has a 350 in it an about 2 months later was burning lots of oil and fouling plugs. I took out the motor and put new crank and rod bearings, new oil pump and honed the cylinders, put on new piston rings and put it back together. Not a top notch rebuild but it solved my problem.



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Old 03-21-2002, 12:07 PM   #15
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I put mobile 1 sythetic in my built 292. I broke it in on castrol 30wt. Now its 10-30 and the oil pressure is a little lower, its like 45-50 psi when going down the road when warm, instead of the 50-55 with the castrol. I agree, its not a good idea to run your engine with it like that. It must be your bearings or oil pump cause I don't think its the oil. Thats my thoughts.

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Old 03-21-2002, 12:16 PM   #16
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sounds like its about to go on you, at least it is warnign you ahead of tiem, alot of times the engine doesnt warn you, it will jusst break on you, the bearings spin, and usually break a rod, lots of screeching and sqealing and engine bogging down until it locks up, how it usually happens, or sometimes youll have rod knock, IE a warning.. sometimes.. ive had it happen both ways to me, so..

good luck
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Old 03-21-2002, 12:24 PM   #17
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Maybe when you bought it, it had thicker oil in it (maybe even to hide a problem) But, unfortunately, the problem will not get better by itself. Sorry.
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Old 03-21-2002, 12:32 PM   #18
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I think you might be right, that would sure fit with the rest of the stuff on the truck. it looked nice, but it had(and still has a lot of problems. It was kind of my fault for not checking the stuff, but every new thing I find makes me a little bit less happy with the guy I bought it from.
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Old 03-21-2002, 04:46 PM   #19
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I know exactly how you fell neonlarry. That is what previous owner did to the 71 I bought from him. Didnt know it at the time but there was thick oil in the crankcase and when the motor began to burn it I replaced it with 10W40 which is what I tought was in it. I started going through oil faster all the time.

Previous owner also told me front end had been aligned. Come to find out all he did was put new shiny shims in there, as the tires started to wear on the edges.

I took a royal screwing on the deal. At least I can say the next owner, when I sell it here in the next month or so will have one heck of a daily driver.

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