oiling system-losing prime

[typentinner]

  i have a 70 cuda 440. it's not exactly stock. i installed a milodon oiling system on the last rebuild. every time i change my oil, it loses prime. to regain prime i have to remove the distributor, insert a drill driven priming rod, and prime the motor. resetting your timing every time you change oil is a pain in the bu--. is there any way to avoid this? i've tried removing the coil wire and turning the motor over with the starter, but the thought of no oil being present during this makes me shy away from this method. it doesn't always work anyway.

[MEK-Dangerfield]

Wow, this is a good one!! 

  I have never heard of such a thing. Thankfully I don't have that problem. Why did you switch to a Milodon anyway? Higher pressure, or what?  Just to add... I did replace my stock pump once in my 440, and never had to prime it. 


  Mike

[Bullitt-]

 

[Grancoupe]

I would consider trying a new pump. Ive always ran Mellings pumps with much success. Did you replace the factory pump for more volume or pressure?

[ShelbyDogg]

I had a dual line Milodon oiling system in my Race car.  I would get oil pressure every week during race season, but the pick-up lines would run dry during winter storage or changing the oil. It is a natural thing for those lines to bleed off due to the dual inputs to the pump. Get used to priming it or put in an accusump to pre oil the system before startup. 

DO NOT wait for the vacuum to pull the oil in by starting the car. The time it takes could kill the engine. At least it only happens when you change the oil. You pre-fill the filter too, right?

[Chryco Psycho]

I assume it has the swinging pick up ?
my guess is that the clearance in the pick up may be excessive allowing it to suck air  , I was surprised how much clearance mine had , & or the clearance in the pump could be excessive so it has a lack of suction , so this is where I would look first
 when drainin gthe oil it will not drain out of the bearings & lifters etc so I`m sure if you started the car & didn`t rev it up the pump would spin fast enough to prime & as long as the new filters are filled with oil it would get pressure fast but I also understand your reluctance to do that as well

[typentinner]

I assume it has the swinging pick up ?
my guess is that the clearance in the pick up may be excessive allowing it to suck air  , I was surprised how much clearance mine had , & or the clearance in the pump could be excessive so it has a lack of suction , so this is where I would look first
 when drainin gthe oil it will not drain out of the bearings & lifters etc so I`m sure if you started the car & didn`t rev it up the pump would spin fast enough to prime & as long as the new filters are filled with oil it would get pressure fast but I also understand your reluctance to do that as well

  thanks for the input, and no, it's the type with a stationary pick up, it sits in the bottom of a  9 quart pan. starting it up, isn't enough. thats when i saw my pressure guage on 0, and shut it down. yes, my filter was as full as possible when installing. what about changing springs in the pump? i've also heard of leaving the filter loose till started.ever try that? i'm thinking of replacing the 3/4 line with one long enough to have an inverted trap.

[MEK-Dangerfield]

From what you have stated, I have NO idea why this is happening to you. I have never heard of a 9 quart pan either.  This fits under an E-Body?  Is the pick-up tube long enough?


   Mike

[ShelbyDogg]

If You know that your pump has good clearances and is good then your inverted trap line may be the way to go.  But with this line full of oil it kind of leaves that much dirty oil in your system during the oil change.  How about adding a "T" fitting with short piece of hose on it with an A-N Plug on the end.  When you change your oil, you could add a quart through this line which will also prime the pump. Just run the hose up the front of the block and tee it at the pump inlet. Make sure that you plug it before startup.

[typentinner]

If You know that your pump has good clearances and is good then your inverted trap line may be the way to go.  But with this line full of oil it kind of leaves that much dirty oil in your system during the oil change.  How about adding a "T" fitting with short piece of hose on it with an A-N Plug on the end.  When you change your oil, you could add a quart through this line which will also prime the pump. Just run the hose up the front of the block and tee it at the pump inlet. Make sure that you plug it before startup.

that makes sense. Thanks for your help. 

[ShelbyDogg]

Typetinner,

I found a possible solution for your dry start problem.   A guy used Lucas Oil Stabilizer to add to his oil and it kept his oil pump primed enough to create a better vacuum to keep it primed,

Did you ever turn the handle on that Lucas Oil Demo device in auto parts stores? The oil really sticks to those gears.   It's might be worth checking this stuff out.   I got tired of pulling my distributor out to prime it all the time too, but I sold my Milodon oiling system 3 years ago and can't try it.

Rob

[OUTLAW]

I know this sounds odd but I have seen it before several times ... what oil filter are you using? Some filters drain back  some don't

[typentinner]

It doesn't sound odd at all. I've heard of that before, infact, i just switched to a k and n filter to try it. Thanks, everyone, for the insight.

[matt63]

Just curious - How did you determine that it was losing it's prime? 

[ShelbyDogg]

Not too hard to tell that your engine doesn't have oil pressure. You start it up, watch the guage, wait, watch it some more, wait, start sweating, wait, decide that it will never get pressure, then shut it off.  The length of time you wait depends on how big your nads are. 

Every spring, I would pull the distro, prime with a shaft till there was pressure, put the distro back in, then fire it up.  Sometimes I would have to pull an oil feed line and dump oil in it to prime the pump or else I would never get pressure with the drill shaft.