new race car, no oil pressure

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71gtdart

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been working on a dart race car for over 3 years. finally get the motor in today, and have zero oil pressure when I tried to prime the it. I know, I know.....I feel like a total jackwagon for not thinking to check that while it was on the stand, but it is what it is.

heres what I do know. the pump is working, because the drill bogged down when it picked up oil. the oil filter is getting oil because it was slam full. from there, I dont see any. I had both valve covers off, to check the flow to the rockers while I was priming, and they are getting no oil.

this is a new 408 with high quality parts. It has a solid roller cam in it, so I had the engine builder install the copper tube kit from Mopar. I inspected it all after he was done, and it seemed correct to me. he had never done a sbm, he mainly does chevy stuff. the work looked good to me. he installed the tube on the passenger side, drilled all the oil holes back through the tube from the mains, and plugged the hole the feeds the drivers side galley. I did notice that he had forgot to put the plug in the block, in front of the distributor. I showed him, and he got it taken care of. so, I know its not that plug missing, that is causing the problem.

I checked behind the oil filter plate, and the correct hole is plugged there.


any of you guys got any ideas on what to check? I am pretty sharp on my mopar engines, but you know how it is, when you get pissed and cant think. thanks for the help guys.
 
Turn motor over by hand while you are priming it. How fast are you turning the pump? did the drill bog down? remove gauge and see if oil comes out of block.
 
Do you have a mechanical gauge hook up to the engine...?

and as said..you will only get oil to the rockers if you slowly turn the engine over by hand while priming the engine...oil to the rockers only happens while the engine is rotating as the cam bearing oil holes and the cam shaft holes line up...oil goes to the rockers....be patient....
 
On a small block:
Turn the motor to 90* before top dead center coming up on #1 compression. The pass. side rockers should get oil.
Turn the motor to 20* after top dead center just past #6 compression. The drivers side rockers should get oil.
 
I believe the others are right that the cam bearings just weren't in the right position to supply oil to the rockers when you primed it. They only supply oil to the rocker shafts for a few degrees in the rotation. Did you put a gauge on it to see if it showed pressure?
 
Did you put all the oil galley plugs in? There is pipe plugs that need to be installed or you will have a internal leak.
 
Tony, I do have an Auto Meter mechanical gauge hooked to it. I unhooked the fitting at the block after I got no oil pressure, and still nothing. I was hoping for a bad gauge or restricted oil line, but looks like its not getting the oil that far.

Scamp, I was turning the pump with a big electric drill, not a cordless. that baby is screaming while it is turning, and you can feel the pump bog the drill just a bit, when it picked up oil. like I had said, it is pumping oil, because the filter is getting pumped full. leaving the filter, is where something is amiss. I want to lean towards a plug being out, but I double checked behind the engine builder as it was coming together. thats how I caught the plug in front of the distributor being out, before it was too late. is it possible that I missed one? sure looks that way, but I wanna think not.

I forgot to mention that I had installed a cross over tube in the lifter valley to feed the rockers, so should'nt they be getting oil now without the engine being turned over while priming? If I'm thinking right, as long as the main oil galley is full of oil and pressurized, it should take the rerouted path of the cross over tube, to the rockers.

thanks again for any suggestions, guys. this is a real pain.
 
71gtdart said:
Tony, I do have an Auto Meter mechanical gauge hooked to it. I unhooked the fitting at the block after I got no oil pressure, and still nothing. I was hoping for a bad gauge or restricted oil line, but looks like its not getting the oil that far.

Scamp, I was turning the pump with a big electric drill, not a cordless. that baby is screaming while it is turning, and you can feel the pump bog the drill just a bit, when it picked up oil. like I had said, it is pumping oil, because the filter is getting pumped full. leaving the filter, is where something is amiss. I want to lean towards a plug being out, but I double checked behind the engine builder as it was coming together. thats how I caught the plug in front of the distributor being out, before it was too late. is it possible that I missed one? sure looks that way, but I wanna think not.

I forgot to mention that I had installed a cross over tube in the lifter valley to feed the rockers, so should'nt they be getting oil now without the engine being turned over while priming? If I'm thinking right, as long as the main oil galley is full of oil and pressurized, it should take the rerouted path of the cross over tube, to the rockers.

thanks again for any suggestions, guys. this is a real pain.
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Very strange. You are correct in assuming that if you've tapped into the main and did a crossover tube you should have oil to heads without turning it over. Seems like the oil is lost between the filter and main, but not sure how without a plug missing at the backside of the motor. You'd notice that quickly with oil everywhere. Only thing I could think of is the copper tube he installed is somehow not done correctly? Bushing lifter bores is pricier option but we'll worth it. Good luck with getting her fired up!
 
even with one missing by dist it will still get pressure. Ck all the plugs were installed most chevy builders don't know where they go. Can you see the lifters ? how big of a roller cam?
 
roller cam has .621" lift intake, and .589" exhaust. I have not looked at the lifters. it was a little late in the day, and one of those times when you just want the thing out of your sight for the time being. What exactly would you be lokking for when you looked at them?

If I'm not mistaken, isn't the only plug that could keep the oil from reaching the oil pressure fitting, the one in the back of the main oil galley, where the tube was installed?

see, Rodzilla has me thinking along the lines of the tube now, as well. the only thing that has to be done there, other than peening the lifter bores, is drive one in the front, one in the rear, drill the holes up from the mains, and the one hole to feed the cross over tube for the rockers, right?

the tube doesn't cover anything in the back coming up from the filter as far as I know, right?
 
Shafts oriented right?They wont feed if installed backwards.One other thing. Small block arp main bolts interfere with the oil pump.You have to clearance the pump for the back bolts. If you dont it causes the gasket to blow out and you will get oil to the filter but not to the top. Ask me how I know.
 
there is another plug that needs to be installed under the rear main cap about 2 inches down that makes oil go to and from the filter without it no pressure. I had the same problem long ago and I always prime the engine on the stand now.
 
sbmmustang said:
there is another plug that needs to be installed under the rear main cap about 2 inches down that makes oil go to and from the filter without it no pressure. I had the same problem long ago and I always prime the engine on the stand now.
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yeah, its in there, I did check that. even if I had not checked it, the oil wouldnt go to the filter with it missing.
 
daredevil said:
Shafts oriented right?They wont feed if installed backwards.One other thing. Small block arp main bolts interfere with the oil pump.You have to clearance the pump for the back bolts. If you dont it causes the gasket to blow out and you will get oil to the filter but not to the top. Ask me how I know.
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shafts are on right, the oil isn't getting to the main oil galley, which is where the cross over tube is installed. I used the ARP main studs instead of the bolts, and also do not use an oil pump gasket.
 
Sounds like you are going to have to pull the intake and see where the internal leak is. It is good you didn't fire the engine like this.
 
after stewing on it for a bit, with a clear head, I have come up with what I believe to be the cause of this whole mess. you guys correct me if I'm wrong. oil leaves the pump and goes straight to the oil filter. when it leaves the oil filter, it goes straight up, and runs to the main oil galley, the port for the oil pressure fitting, and to the rear main and cam journal bearings. is that correct?

if so, my thought is that he has drove the rear tube just far enough into the block, to cover the last 4 lifter holes, and has the main oil feed coming up from the oil filter, covered with the copper tube. that kit has 2 copper tubes in it. one drives in from the front, and covers the first 4 lifter oil holes. then, the other come in from the back, and covers the remaining 4 lifter oil holes. if he only drove the tubes in far enough to cover the oil holes, there would be "empty space" between the 4th and 5th lifter bores. in other words, the tubes would not be butted up end to end. that space would be a couple inches long. meaning there would be more room to drive that rear tube, and doing so would uncover the oil feed hole coiming up from the oil filter. any thoughts on that theory?
 
71gtdart said:
after stewing on it for a bit, with a clear head, I have come up with what I believe to be the cause of this whole mess. you guys correct me if I'm wrong. oil leaves the pump and goes straight to the oil filter. when it leaves the oil filter, it goes straight up, and runs to the main oil galley, the port for the oil pressure fitting, and to the rear main and cam journal bearings. is that correct?

if so, my thought is that he has drove the rear tube just far enough into the block, to cover the last 4 lifter holes, and has the main oil feed coming up from the oil filter, covered with the copper tube. that kit has 2 copper tubes in it. one drives in from the front, and covers the first 4 lifter oil holes. then, the other come in from the back, and covers the remaining 4 lifter oil holes. if he only drove the tubes in far enough to cover the oil holes, there would be "empty space" between the 4th and 5th lifter bores. in other words, the tubes would not be butted up end to end. that space would be a couple inches long. meaning there would be more room to drive that rear tube, and doing so would uncover the oil feed hole coiming up from the oil filter. any thoughts on that theory?
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I just looked at the oil schematic in a 70 service manual and after the oil leaves the filter it branches off in 2 directions. 1 way is to the pass side lifter oil galley. The other direction is to feed all the other parts you mentioned. From what it looks like to me on the schematic I can't see how driving the tube in too far will do that. I scanned and posted a picture of the oiling schematic. The picture came out kinda small so it's not easy to see but the galley leading away from the filter goes over, tee's off to the pass side lifter galley and over to the other items

Something that Dardevil mentioned is the fact that if you use ARP main studs the oil pump will no longer bolt on properly. You have to either use a bolt on the one side where the pump is or machine down the man cap .070-.100", cut the stud down a bit and use a thinner nut than they send, and possibly even grind down the pump body for more clearance. It's real tight in there already and the ARP bolt and nut add a bunch to the height.

Another possibility is you got a defective oil filter. You said it's full but is it letting oil flow? Just another thought that'd be an easy thing to test.
 

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Are the copper tubes short enough to have a gap between them and still be able to plug the galley? If so, it sounds plausible. I bought the same tube kit as you have and when I dropped off my block to my machinest he went over the pros & cons vs having lifter bores bushed. It didn't take long to sway me to having bushings put in. If you find out your machinest screwed up on tubing the main I'd be hesitant to use him again but if you do shoot for getting a sweet deal on bushing lifter bores. More strength and precision involved in the process. Again, best of luck in solving your problem.
 
71gtdart said:
shafts are on right, the oil isn't getting to the main oil galley, which is where the cross over tube is installed. I used the ARP main studs instead of the bolts, and also do not use an oil pump gasket.
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you must grind clearance on the oil pump if using arp studs if not your pump will not seat right which will cause no oil pressure there are many threads on it here.
 
Has the little cap plug under the rear main cap been put in to far?? There is a small step in the oil galley and if the plug is pushed past it will block off the galley that feeds the top end. Just a thought.
 
fishy68 said:
I just looked at the oil schematic in a 70 service manual and after the oil leaves the filter it branches off in 2 directions. 1 way is to the pass side lifter oil galley. The other direction is to feed all the other parts you mentioned. From what it looks like to me on the schematic I can't see how driving the tube in too far will do that. I scanned and posted a picture of the oiling schematic. The picture came out kinda small so it's not easy to see but the galley leading away from the filter goes over, tee's off to the pass side lifter galley and over to the other items

Something that Dardevil mentioned is the fact that if you use ARP main studs the oil pump will no longer bolt on properly. You have to either use a bolt on the one side where the pump is or machine down the man cap .070-.100", cut the stud down a bit and use a thinner nut than they send, and possibly even grind down the pump body for more clearance. It's real tight in there already and the ARP bolt and nut add a bunch to the height.

Another possibility is you got a defective oil filter. You said it's full but is it letting oil flow? Just another thought that'd be an easy thing to test.
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not driving the tube in to far, not driving it in far enough. if he only drove it in far enough to get past that last lifter bore, then he could have the passage coming up from the oil filter blocked off.

also, I wish it were as simple as a defective oil filter, but I already tried another one, and got the same result.
 
Black 69 Dart said:
Has the little cap plug under the rear main cap been put in to far?? There is a small step in the oil galley and if the plug is pushed past it will block off the galley that feeds the top end. Just a thought.
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I do remember it being in the engine, but the depth could be incorrect, and you could be on to something. will have to check that out.
 
jimjimjimmy said:
you must grind clearance on the oil pump if using arp studs if not your pump will not seat right which will cause no oil pressure there are many threads on it here.
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thanks Jim, I will give it a look, as it appears coming back out for a tear down is a given at this point.
 
I'm not very well versed on this kind of thing, But I'll take a shot.

Years ago, a 383 I had lost oil pressure. After chasing my tail for a while, I found that a piece of debris got stuck in the oil pressure relief valve piston. I don't remember how it works, but basically, it couldn't make pressure with the piston in the position it got stuck in.
I would think you would still feel the oil hit the pump gears when you prime it ifit were stuck.

Good luck.
 
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