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Oil pressure problem?

2K views 39 replies 7 participants last post by  kwiktsi 
#1 ·
Hey guys, I just got my motor back together today after replacing a broken piston (detonation) and bent pushrods (over rev). Got it all done and fired up and the valvetrain is noisy as hell and I'm barely getting any oil up top. I do not have a gauge on the car to check pressure, but there is obviously an issue. I pulled the pan again to check the o ring on the pick up and basic stuff, I even pulled the rod caps to make sure the bearings weren't running dry. O ring, pickup, oil pan gasket, etc. were all good and bearings looked fine with what appeared to be plenty of oil going to them (but the car has not been driven, just idled- not going to risk blowing it up obviously).

I know these cars have oil pump issueds, but I can't see it being good prior to parking it last week and being bad now. Is it possible something in the pump broke when it was over revved (~8400 on a mis shift)? Also, when I was doing the ARP's and rotating the crank with a socket, I would hear a "click" that sounded like it was coming from the oil pump area with every rotation, but I just assumed it was because there was no oil in the pump and the pickup and such were off, maybe not....

Is it possible to pull the pump without dropping the pan on this motor? Is it possible there is a broken bypass spring or something? Or- should I be looking elsewhere? I would hook a gauge up to check pressure, but it is obvious it has to come apart anyway.

Last thought- I bought Trick Flow pushrods from Summit (stock cam, springs, etc. so I didn't need anything crazy)- any known issue with them? Although, they should be fine- the length was the same, etc.

I just figured I'd ask those who have had the engine apart and/or had oil pump issues before going much further. Thanks.
Joe
 
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#4 ·
Hmm, didn't know that. Maybe it is sucking air around it then. It seems to be snug though when I assemble it. I'll have to keep that in mind. Thanks.
Joe
 
#5 ·
fastgoat said:
Ive read about this happening before on ls1tech, do a search over there and see what their issue is
Thanks for the advice. I am searching there with no luck though :(. I never seem to get the right key words..
Joe
 
#9 ·
I'm just trying to imagine why the oil not going to the head so easy.

May be the place where the oil goes has a problem, I don't know how the engine looks inside but may be there is a gasket or a hole some where that is makes the pressure drops when the oil goes to the head.


I'm not an exprert in any way, but I would check like this when investigating the problem.



:bewarespa
 
#10 ·
When I was working on my Camaro, they said there was some kind of plug at the back of the engine by the bellhousing that some people forget about. Also, if you've added a double-roller chain, there are shims that come with it. If the holes in those aren't lined up with the holes in the block, you won't get good pressure.
 
#11 ·
Yeah, this is a simple setup for the most part- the passages are all cast into the block and it just picks it up from the sump and pumps it through. I don't know why it didn't act up prior to taking the car apart, but I am really wondering if the over rev did something to the oil pump.

I know these cars are known for oil pumps going bad and the bypass valves hanging up- is it possible that the valve could stick from small crap like head gasket shavings or something (the silicone seal on the gasket)?
Joe
 
#12 ·
Jake99SS said:
When I was working on my Camaro, they said there was some kind of plug at the back of the engine by the bellhousing that some people forget about. Also, if you've added a double-roller chain, there are shims that come with it. If the holes in those aren't lined up with the holes in the block, you won't get good pressure.
Thanks for the reply, but that's not it. All I did was drop the pan, remove one rod to replace the piston, put it back in, swap all the rod bolts to ARP's and replace the pushrods. Shouldn't be this difficult lol. That's why I said that if it is a bad pump from the over rev, it is odd that it was fine for several hundered miles, then the car was parked, taken apart, sat for a week and a half and put back together and NOW it is acting up. I'm stumped, but don't want to take it apart if there is a simple solution. Just odd that the bearings looked fine and plenty of oil, but hardly anything is coming out of the pushrods.
Joe
 
#13 ·
you replaced most of the valve train? you are getting oil at the rocker arms ? is that right. then you have oil pressure. how long did you let it run? sometimes it can take awhile for lifters to pump up. also did you check rod length. also if you got any coolant in lifters at all when pulling the heads they will make noise as well. but before you start tearing stuff apart again for nothing verify pressure.
 
#14 ·
I am getting a VERY slow tricle out of the rockers- when anything at all comes out. I am going to hook a gauge to it tomorrow to double check, if it has good pressure, then I'll wait to see if they pump up, but it has been run for about 5-7 minutes or so with no change in sound and, for obvious reasons, I did not want to let it run too long without a gauge on it. My bearings are good and there was oil running out of the crank passages- thankfully- so it is getting oil to the bearings at leasr and it didn't cook the bottom end!! Just very little getting up top.

Pushrods were the same length also- triple checked them, and no coolant down into the motor/lifter valley upon disassembly. This is all why I am so stumped, my gut is saying oil pump- but it was fine when I parked it to disassemble it. Only thing now that I think about it is the car had a clicking sound coming from it when running that sounded like a lifter noise- I just assumed that was one of the bent pushrods I found causing it. Now I am wondering if it was the pump. I have never seen an Lsx pump to know what they look like or how they function, so it may not even be possible that it was the noise. Thanks Mike!
Joe
 
#15 ·
kwiktsi said:
I am getting a VERY slow tricle out of the rockers- when anything at all comes out. I am going to hook a gauge to it tomorrow to double check, if it has good pressure, then I'll wait to see if they pump up, but it has been run for about 5-7 minutes or so with no change in sound and, for obvious reasons, I did not want to let it run too long without a gauge on it. My bearings are good and there was oil running out of the crank passages- thankfully- so it is getting oil to the bearings at leasr and it didn't cook the bottom end!! Just very little getting up top.

Pushrods were the same length also- triple checked them, and no coolant down into the motor/lifter valley upon disassembly. This is all why I am so stumped, my gut is saying oil pump- but it was fine when I parked it to disassemble it. Only thing now that I think about it is the car had a clicking sound coming from it when running that sounded like a lifter noise- I just assumed that was one of the bent pushrods I found causing it. Now I am wondering if it was the pump. I have never seen an Lsx pump to know what they look like or how they function, so it may not even be possible that it was the noise. Thanks Mike!
Joe
good to here your car is back together, sorry to here you have a oil psi problem hope you get it fixed soon. is the oil thats coming out the push rods even at all the rods, and is it about a half tsp per rise. that should be about the norm. you mite have crushed the lifters. with the over rev.
 
#16 ·
Yeah, it isn't much oil at all that I am getting- less than half a tsp, that's for sure- maybe a couple of drips here and there. It looks like there were air bubbles in the oil that was coming out and puddling in the head which is what made me think it was sucking air around the pick up, but that checked out ok. I was wondering about the lifters also- but why the hell were they fine up until I parked it lol. That's what is stumping me!! I need to check the oil pressure before I go any further. That will tell me a lot right there. Can you do the lifters on this motor without pulling the heads? I don't remember how it was set up.
 
#17 ·
Also, no- it wasn't at all the pushrods, just occasional drips from a few here and there.
Joe
 
#18 ·
I should also say- I was thinking the lifters maybe, but all of them at once when I restarted the car? It sounds a bit too far fetched for me, but I have seen stranger things happen!
Joe
 
#19 ·
kwiktsi said:
Yeah, it isn't much oil at all that I am getting- less than half a tsp, that's for sure- maybe a couple of drips here and there. It looks like there were air bubbles in the oil that was coming out and puddling in the head which is what made me think it was sucking air around the pick up, but that checked out ok. I was wondering about the lifters also- but why the hell were they fine up until I parked it lol. That's what is stumping me!! I need to check the oil pressure before I go any further. That will tell me a lot right there. Can you do the lifters on this motor without pulling the heads? I don't remember how it was set up.
not sure on this motor, have'nt been in oun just yet, but norm. no. would look at the psi like mike was saying and if you have the 40-60 lb then I'd give her a small couple revs to see if you can get the air out. sucks it's by wire I like to be under the hood when I'm doing stuff like that to keep a good eye on things.
 
#21 ·
got cut off last knight, but the other thing that it could be is the prime. some oil pumps are tricky, when it come to that . the old small block I'd use a drill to prime them, most ext. oil pumps would ask to have vaseline stuffed into them when installing. had the old 3.8 in my buick, was 20 mi from a store and that was the only car at the house. was replaceing the oil pump gears and then I seen I didn't have any, but I did have butter.:) got the prime then changed the oil after the butter was warm enought to come out. I will pick a friend brain that works at the dealership. see what it could be and how the pump sould be primed, if needed. good luck will post back
 
#22 ·
LOL @ the butter haha. There is no way to really prime this pump, but someone said there is a pre lube hole on the motor that needs oil pumped into it. I just can't see it being that "dry" since it was running a week ago. I think I am going to yank the pump today for the hell of it, I would rather do that then take the chance of damaging the motor.
Joe
 
#23 ·
Heh, pulled the pump and the pump and bypass valve are in perfect working order. This is killing me, it is going to be something so stupidly simple, I know it... I'm going to be pissed if the lifters are bad for some reason and I have to pull the heads off it.
Joe
 
#24 · (Edited)
kwiktsi said:
Heh, pulled the pump and the pump and bypass valve are in perfect working order. This is killing me, it is going to be something so stupidly simple, I know it... I'm going to be pissed if the lifters are bad for some reason and I have to pull the heads off it.
Joe
sorry man I plum forgot to call my guy up, sorry. hope your having some luck on your end. all in time she'll get back.
 
#25 ·
just checked some things. first we still don't know what your pressures are. but if all other things you checked are ok. excessive bearing clearance, oil passages plugged or cracked, broken lifters, is the one that stands out for me, with an over rev.
 
#26 · (Edited)
mikesgtoinvegas said:
just checked some things. first we still don't know what your pressures are. but if all other things you checked are ok. excessive bearing clearance, oil passages plugged or cracked, broken lifters, is the one that stands out for me, with an over rev.
yea, that what I would think too.also would have to get psi reading before to make sure. if the psi is there then that is it. edit he must be under the car I tried to e-mail him.
 
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