No oil when priming
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Teching In
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No oil when priming Hello everyone. I have a technical question. I recently had a 408 built. ATK short block. Ls3 heads, comp cam 459-11, melling oil pump, and upgraded rockers, springs ect... I am trying to prime it, I've hooked up a pressure bottle which is feeding oil to the motor through the plug on the driver side toward the front. From my understanding I t should come up through the oil sending hole, and then the rockers. I CANNOT get it to go to either one. I pumped 5 quarts through after putting 5 quarts in the pan initially. So 10 quarts and its just all in the oil pan. Am I missing something here? Did my machinist put something together wrong? I'm just trying to figure out why it won't prime. Maybe the gally plug wasnt installed? I tried to turn the crank a few times and everything is moving and I can here air coming out the back oil sending hole. Any help would be much appreciated 🙏 Also the engine is on the stand still , not in the car
Last edited by Jayson3460; Jun 18, 2023 at 07:46 PM.
Thread Starter
Teching In
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You should get oil to the top with a pressure primer.
Thread Starter
Teching In
Joined: Apr 2018
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Just pull the rear cover and check the barbell. If it’s in place, pull it out gently, and shine a light through the galley to see if the front plug is in place. While the rear cover is off, pull the oil filter and use your light to see if there are blockages from the filter boss, up toward the pressure sender port. Speaking of the oil filter, is it full of oil?
You should get oil to the top with a pressure primer.
You should get oil to the top with a pressure primer.
While it’s on the stand, it’s soooo easy to double check things now, vs in the car. If oil is spraying out the pressure sensor hole in a strong fashion, I’d feel good about throwing it in the car. I personally don’t put a lot of weight in pre-lubing an engine. GM has built many, many million engines, and never pre-lubed any of them. I don’t pre-lube my own stuff, UNLESS its got a dry-sump pump that I can attach a drill to. It’s just not worth the effort to me. I pre-fill my oil filters, back fill the oil circuit through the oil pressure sensor port, and fire it. Instant oil pressure every time.
Thread Starter
Teching In
Joined: Apr 2018
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While it’s on the stand, it’s soooo easy to double check things now, vs in the car. If oil is spraying out the pressure sensor hole in a strong fashion, I’d feel good about throwing it in the car. I personally don’t put a lot of weight in pre-lubing an engine. GM has built many, many million engines, and never pre-lubed any of them. I don’t pre-lube my own stuff, UNLESS its got a dry-sump pump that I can attach a drill to. It’s just not worth the effort to me. I pre-fill my oil filters, back fill the oil circuit through the oil pressure sensor port, and fire it. Instant oil pressure every time.
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Thanks for the response. Today I built a pressure bottle with one of those weed sprayers, and I was able to get oil to the oil pressure sender. I am also getting oil there now when turning the crank by hand repeatedly... BUT I have yet to get oil to the top of the rockers yet, Is this ok? I thought I would be able to get them there. Maybe I need to get the engine in the car and crank it without fuel. But have not succeeded in priming to the rockers by hand or with my pressure bottle
I did mine with a 4" pc. of PVC, capped at one end with glue on cap, the other end with screw on cap. Put an air quick disconnect in the screw on end, filled with 6.5qts oil, cranked the air comesqueezer down to 40lbs, and applied the air over oil primer. Worked great, oil out the PRs, good to go......
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From: Wilmington, De
Thanks for the response. Today I built a pressure bottle with one of those weed sprayers, and I was able to get oil to the oil pressure sender. I am also getting oil there now when turning the crank by hand repeatedly... BUT I have yet to get oil to the top of the rockers yet, Is this ok? I thought I would be able to get them there. Maybe I need to get the engine in the car and crank it without fuel. But have not succeeded in priming to the rockers by hand or with my pressure bottle
Also, did you install the oil pump dry?
Did we forget what engine assembly lube is used for? All i've ever done after engine assembly was fill the oil filter and add engine oil prior to installation in the car. With the iginition coils disconnected and the fuel pump relay removed start turning the engine over 6-8 revolutuions and after about 2-3 times you should see oil pressure on a mechanical gauge. Re-connect the coils and the fuel pump relay then start it up. If you are relying on an electronic gauge you can still perform this procedure prior to ignition and if you don't see pressure right away then shut it down.
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Turn the crank 1/2- 1 turns and prime some more. It will come out of the rockers, it just takes a long, long time. Remember, the oil also back fill thru the oil pump too. This is why it takes so long time wise
When I used my homemade air over oil contraption, which does basically what the weed sprayer does, it didn't take that long before it came out thru the PRs and made a Helluva mess. I'm talking within 25-30 seconds, tops. But I also ran air pressure at 40psi. IDK what pressure the sprayers can achieve.....
Last edited by grinder11; Jul 1, 2023 at 07:12 PM.
When I used my homemade air over oil contraption, which does basically what the weed sprayer does, it didn't take that long before it came out thru the PRs and made a Helluva mess. I'm talking within 25-30 seconds, tops. But I also ran air pressure at 40psi. IDK what pressure the sprayers can achieve.....
