Oil Pressure ?? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

neonlarry · 03-21-2002, 02:15 AM

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.

jostrans68 · 03-21-2002, 02:20 AM

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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68 c20 in progress 327 TH400 tach dash Disc Brakes and soon 3.90 rear gears.. have many new parts now just need the time..... Sound Familar

neonlarry · 03-21-2002, 02:22 AM

it is the factory gauge, and yes, it sounds awful, that is the main reason i was asking about it.

imdarren · 03-21-2002, 02:33 AM

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.

neonlarry · 03-21-2002, 02:40 AM

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

jostrans68 · 03-21-2002, 02:41 AM

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

------------------
68 c20 in progress 327 TH400 tach dash Disc Brakes and soon 3.90 rear gears.. have many new parts now just need the time..... Sound Familar

neonlarry · 03-21-2002, 02:42 AM

Would the weight of the oil make a difference? I don't remember what it is, but I can look tomorrow.

imdarren · 03-21-2002, 02:54 AM

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

neonlarry · 03-21-2002, 02:59 AM

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

imdarren · 03-21-2002, 03:04 AM

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.

neonlarry · 03-21-2002, 03:08 AM

thanks, I will check back tomorrow.

bigjimzlll · 03-21-2002, 08:14 AM

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

neonlarry · 03-21-2002, 11:32 AM

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

boilrman · 03-21-2002, 11:46 AM

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.

------------------
1971 Chevy 1/2t, 350
1998 Yamaha V-Star 650
1970 Chevy 3/4t, I6(freshly rebuilt), 4 speed
Keokuk,IA

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stelth2002 · 03-21-2002, 12:07 PM

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.

------------------
67 Chevrolet LWB with rebuilt 292. 415 ft. lbs of torque, 4 speed, 3.73 Posi, straight and almost painted.

*Fast68Chevy* · 03-21-2002, 12:16 PM

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

busterwivell · 03-21-2002, 12:24 PM

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.

neonlarry · 03-21-2002, 12:32 PM

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.

boilrman · 03-21-2002, 04:46 PM

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.

------------------
1971 Chevy 1/2t, 350
1998 Yamaha V-Star 650
1970 Chevy 3/4t, I6(freshly rebuilt), 4 speed
Keokuk,IA

http://communities.msn.com/SchweringFamily/shoebox.msnw

MSN Messenger = boilrman
Find a job you love and you'll never have to work a day in your life.

03-21-2002, 02:15 AM	#1
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	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. __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

03-21-2002, 02:20 AM	#2
jostrans68 Jostrans68 Join Date: Mar 2001 Location: Bloomington indiana Posts: 1,182	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 ------------------ 68 c20 in progress 327 TH400 tach dash Disc Brakes and soon 3.90 rear gears.. have many new parts now just need the time..... Sound Familar __________________ [CGTW Member former 67-72 now with a 96 silverado

03-21-2002, 02:22 AM	#3
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	it is the factory gauge, and yes, it sounds awful, that is the main reason i was asking about it. __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

03-21-2002, 02:33 AM	#4
imdarren Registered User Join Date: Oct 2001 Location: SW Washington Posts: 1,006	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. __________________ Washington State 1967 Chevy C10 LWB Rodstoration In Progress. 1972 K20 Cheyenne Super

03-21-2002, 02:40 AM	#5
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	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 __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

03-21-2002, 02:41 AM	#6
jostrans68 Jostrans68 Join Date: Mar 2001 Location: Bloomington indiana Posts: 1,182	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 ------------------ 68 c20 in progress 327 TH400 tach dash Disc Brakes and soon 3.90 rear gears.. have many new parts now just need the time..... Sound Familar __________________ [CGTW Member former 67-72 now with a 96 silverado

03-21-2002, 02:42 AM	#7
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	Would the weight of the oil make a difference? I don't remember what it is, but I can look tomorrow. __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

03-21-2002, 02:54 AM	#8
imdarren Registered User Join Date: Oct 2001 Location: SW Washington Posts: 1,006	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 __________________ Washington State 1967 Chevy C10 LWB Rodstoration In Progress. 1972 K20 Cheyenne Super

03-21-2002, 02:59 AM	#9
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	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 __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

03-21-2002, 03:04 AM	#10
imdarren Registered User Join Date: Oct 2001 Location: SW Washington Posts: 1,006	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. __________________ Washington State 1967 Chevy C10 LWB Rodstoration In Progress. 1972 K20 Cheyenne Super

03-21-2002, 03:08 AM	#11
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	thanks, I will check back tomorrow. __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

03-21-2002, 08:14 AM	#12
bigjimzlll Senior Member Join Date: Dec 2001 Location: Redding,CA...USA Posts: 4,736	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 __________________ It's called "drag racing" if they called it "tic..tic..WHAM!..BANG! F*&K!!!", they'd have to keep the magazines under the counter with the other men's publications click the clicky to join the site.... http://67-72chevytrucks.com/vboard/payments.php 67 lwb..first hotrod in 25 years..540 best ET is 9.45 @ 141.44 Anderson,CA

03-21-2002, 11:32 AM	#13
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	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 __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

03-21-2002, 11:46 AM	#14
boilrman 70 Chevy 3/4t Join Date: Sep 2000 Location: Kokomo,IN USA Posts: 1,230	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. ------------------ 1971 Chevy 1/2t, 350 1998 Yamaha V-Star 650 1970 Chevy 3/4t, I6(freshly rebuilt), 4 speed Keokuk,IA http://communities.msn.com/SchweringFamily/shoebox.msnw MSN Messenger = boilrman Find a job you love and you'll never have to work a day in your life. __________________ Find a job you love and you'll never have to work a day in your life. 1998 Yamaha V-Star 650 1970 Chevy 3/4t, I6 (rebuilt), 4 speed Kokomo,IN

03-21-2002, 12:07 PM	#15
stelth2002 Young Gun wth Fast Inline Join Date: Jan 2002 Location: Idaho Posts: 1,475	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. ------------------ 67 Chevrolet LWB with rebuilt 292. 415 ft. lbs of torque, 4 speed, 3.73 Posi, straight and almost painted. __________________ 1967 Chevrolet LWB with built 292! 415 ft. lbs of torque, 4 speed :O with 27% overdrive too, 3.73 Posi. Frame and body done... getting painted!!!



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03-21-2002, 12:16 PM	#16
Fast68Chevy Account Suspended Join Date: May 2000 Location: IL Posts: 0	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

03-21-2002, 12:24 PM	#17
busterwivell Registered User Join Date: Jan 2002 Location: Sahuarita, AZ USA Posts: 2,033	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. __________________ Bill - Tucson, AZ 47 Chevrolet 2 dr sedan 56 Chevrolet 210 2 dr sedan 66 Chevrolet Malibu 2 dr 4 speed 71 Chevrolet C30 Longhorn 86 Chevrolet Monte Carlo SS (Sold) 01 Chevrolet Tahoe IM - BUSTERWIVE@aol.com

03-21-2002, 12:32 PM	#18
neonlarry Registered User Join Date: Feb 2002 Location: Vacaville, CA Posts: 2,746	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. __________________ 70 C/10 Light Red 350/TH350, HEI, Duals w/40 series Flows, 91 seat, LED taillights 99 Pontiac S/C GTP, SLP Ram Air hood, GMPP Konis & springs 95 Neon ACR, MP PCM, AFX UDP, 3.0 CAI

03-21-2002, 04:46 PM	#19
boilrman 70 Chevy 3/4t Join Date: Sep 2000 Location: Kokomo,IN USA Posts: 1,230	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. ------------------ 1971 Chevy 1/2t, 350 1998 Yamaha V-Star 650 1970 Chevy 3/4t, I6(freshly rebuilt), 4 speed Keokuk,IA http://communities.msn.com/SchweringFamily/shoebox.msnw MSN Messenger = boilrman Find a job you love and you'll never have to work a day in your life. __________________ Find a job you love and you'll never have to work a day in your life. 1998 Yamaha V-Star 650 1970 Chevy 3/4t, I6 (rebuilt), 4 speed Kokomo,IN

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