How long should it take?

[Steve Cole]

I am doing a LS swap and my motor has sat for 2.5 years. (I know) I changed the oil pump, water Pump, and every seal and gasket I could. I also replaced the oil pan so pretty much all the oil was removed from the engine. I attempted to build oil pressure today- I disconnected the coils and the fuel tank is bone dry. I tried cranking over the motor while watching a oil pressure gauge I connected. The needle never moved. I motored it multiple times, 5-10 seconds at a time. The needle never moved. They say to prime the oil pump when you have install it but I can't remember if I did that. So my question is, how long should it take to build oil pressure under these conditions?
Any suggestions what I should do?
Thanks!

[saxart]

It's probably not going to build oil pressure by hitting the starter at "5-10 seconds at a time". You really should pull the distributor and use an oil pump priming tool. You should be able to rent one for free or cheap at your local auto parts store.

[Steve Cole]

Hi Saxart, it is an LS motor, so no distributor. I don't know of a good way to prime these motors if it's already full of oil.

[Thealien]

When I did mine many years ago I removed the plugs and let it spin. It took a little while but it did build pressure.

[hjewell2]

https://youtu.be/539ClWWJMl8

[Steve Cole]

Originally Posted by hjewell2

https://youtu.be/539ClWWJMl8

Great info, thanks!!!

[saxart]

Originally Posted by Steve Cole

Hi Saxart, it is an LS motor, so no distributor. I don't know of a good way to prime these motors if it's already full of oil.

Um... Wow... What a "senior moment" on my part. LOL. Sorry... Yeah, maybe don't take that advice. You said "LS" and for some reason I skipped right over that and started thinking of the SBC in my truck.

Let us know if you resolved the issue with the YouTube video.

[71cheyennesuperlongb]

When you put the new oilpump on I think you have to shim the pump,like with feeler guages three places to center the pump or no oil pressure.Someone who knows more than I do can set you straight. I do know moroso sells a pump primer for the LS engines.

[57taskforce]

Lots of people have issues with the pickup tube o-ring not seating correctly and or getting cut when installing it into the pump especially if the pump replacement was done with the engine in the car or truck. If you pull the galley plug and fill the pump like the video above shows it should build pressure pretty quickly. If not I’d suspect an issue with the o-ring.

[Wrenchbender Ret]

Years ago I built a pressureiser out of an old fire extenquisher. I put a valve stem in the side near the top. Irun a hose from the outlet to the oil pressure outlet on the engine. I put a quart of oil in the tank & put air pressure to the valve stem watching the gauge.
Pull the trigger & pressure goes into the oil gallery. I have used this for 50 years & hundreds of engines. The oil pressure comes up as soon as the engine starts.
This also works good for checking low oil pressure problems. With the oil pan off I put pressure to the system & watch for excess flow.

George

[70c10resto]

I never could get oil pressure by just cranking over either. I ended up buying a priming tool from jegs and got instant oil pressure.

[special-K]

Originally Posted by saxart

Um... Wow... What a "senior moment" on my part. LOL. Sorry... Yeah, maybe don't take that advice. You said "LS" and for some reason I skipped right over that and started thinking of the SBC in my truck.

It might be that since this is the 67-72 truck forum your mind went to the mechanics of 67-72 trucks, which is what this forum is for. 67-72 GM Trucks have distributors. The only "moment" going on here was posting an LS question where it doesn't belong

[Bones72Super]

X2 on the oil pump, pick up tube O-ring . If you get a used LS, that O-ring MUST BE REPLACED. they get hardened over time and shrink/crack and then it's like trying to drink from a straw with a hole in it.

[57taskforce]

Originally Posted by special-K

It might be that since this is the 67-72 truck forum your mind went to the mechanics of 67-72 trucks, which is what this forum is for. 67-72 GM Trucks have distributors. The only "moment" going on here was posting an LS question where it doesn't belong

I don’t feel this comment was necessary. A simple move of the post to the forum you felt necessary would have been fine. Maybe it’s just me...

[cornerstone]

Originally Posted by 57taskforce

I don’t feel this comment was necessary. A simple move of the post to the forum you felt necessary would have been fine. Maybe it’s just me...

Nope... Not just you.

[Willie Makeit]

Originally Posted by 57taskforce

I don’t feel this comment was necessary. A simple move of the post to the forum you felt necessary would have been fine. Maybe it’s just me...

also notice the post also had nothing to offer help-wise other than insulting & berating the original poster. about part for the course.

[57taskforce]

Originally Posted by Willie Makeit

also notice the post also had nothing to offer help-wise other than insulting & berating the original poster. about part for the course.

Yes sir, Lots of things I could say here but i remember what mom said about saying nice things.
OP, did you ever get pressure?

[halfstep]

My favorite part was reading that an LS engine question posted in the LSx swap section was "...posting an LS question where it doesn't belong"!!!??

Good suggestions already presented and even more creative solutions online. I will add that as important as priming is it isn't nearly as critical on an engine that has already been broken in and has decent run time on rings, bearings, etc.

[57taskforce]

Originally Posted by halfstep

My favorite part was reading that an LS engine question posted in the LSx swap section was "...posting an LS question where it doesn't belong"!!!??

Good suggestions already presented and even more creative solutions online. I will add that as important as priming is it isn't nearly as critical on an engine that has already been broken in and has decent run time on rings, bearings, etc.

I can see where your coming from, for those who didn’t see it originally it was posted in main 67-72 board. That still didn’t require the aforementioned useless response.

[Steve Cole]

Hi Guys,

Thanks for all the replies...except one. A little update- I did the oil pump priming procedure that hjewall2 posted. This works great BTW. Long story short.. still no oil pressure but the engine won't start either. I don't think I am going to build oil pressure until the engine actually starts short of some fancy priming rig. I pulled a spark plug and zero evidence of fuel smell on the plug. I put a noid light on the injector harness and they are being commanded to pulse so tomorrow I'm taking my injectors to be cleaned/flow checked. I believe they are gummed up from sitting so long. I will keep everyone posted!

[Willie Makeit]

Originally Posted by Steve Cole

Hi Guys,

Thanks for all the replies...except one. A little update- I did the oil pump priming procedure that hjewall2 posted. This works great BTW. Long story short.. still no oil pressure but the engine won't start either. I don't think I am going to build oil pressure until the engine actually starts short of some fancy priming rig. I pulled a spark plug and zero evidence of fuel smell on the plug. I put a noid light on the injector harness and they are being commanded to pulse so tomorrow I'm taking my injectors to be cleaned/flow checked. I believe they are gummed up from sitting so long. I will keep everyone posted!

while a buddy tries to crank the engine, take a screwdriver and lightly tap the injectors one at a time with the handle-end until you can feel them open. you should feel a small "click". used this method several times on LS injectors in engines that sat for a while and the injectors almost always decide to work rather than being hit by the screwdriver.

you may want to check your fuel pressure at the fuel rail as well. should have 58 psi.

[Steve Cole]

Thanks Willie, great advice! I'm guessing you check fuel pressure at the Schrader valve on the crossover tube?

[Willie Makeit]

Originally Posted by Steve Cole

Thanks Willie, great advice! I'm guessing you check fuel pressure at the Schrader valve on the crossover tube?

yes sir. you can pick up an inexpensive fuel pressure gauge at most big box automotive stores.

[Steve Cole]

I picked up one today Willie. Decided to go ahead and have the injectors cleaned and flow checked as well.

[CarlsLQ9SS]

I made a priming tool from an old small block chevy oil pump. Just put a drill on the drive shaft of the pump, dropped the pump in a bucket of oil, and ran a hose from the pump to the plug on the driver lower front of the block it worked really well. It is the plug that takes an alan wrench to take it off.