Oil pressure

My SPF has a 402 Roush engine with an adjustable oil pump. I'm still on break in oil at 2700 miles. The pressure seems low when the oil is on temperature at 40 pounds. Does anyone have any advice on what pressure to run at and how to adjust the pump?

Thanks!
 

Tim Kay

Lifetime Supporter
My dry sump pump has an adjusting allen bolt with a lock nut, increase\decrease direction indicated on housing or manual. At temperature mine sits around mid 40s at idle but increases to 60 upon acceleration.
 

Rick Muck- Mark IV

GT40s Sponsor
Supporter
Roush specs 10-30 oil.

My Roush 427 SR ran at 40 pounds warm, 50 cold. Never had an issue. I think it is their way with clearances, etc. as the Roush motors are know to use a fair bit of oil.
 

Mike

Lifetime Supporter
Do it soon! I changed mine every 1000 or so even after break-in. Oil is cheap!
 
Roush specs 10-30 oil.

My Roush 427 SR ran at 40 pounds warm, 50 cold. Never had an issue. I think it is their way with clearances, etc. as the Roush motors are know to use a fair bit of oil.

Same with my 427SR. When you say adjustable do you have an external dry sump pump?
 
Thanks guys, Mine is wet sump. The oil level was running a bit low. I'm not sure that the dipstick indicates properly. And I'm thinking the pick up sits fairly high, resulting in the lower pressure. I added 1 quart and it was back to normal. I'll be changing to the synthetic soon. Roush recommends 3000 miles of break in. Maybe they had issues with proper seating of the rings?
 

Howard Jones

Supporter
1. pick up should be 3/8 inch above the bottom of the pan or in the case of a dry sump the "pan" is the collector, replacing the OEM pickup and pump, for the return lines to the belt driven pump. If the OEM pickup is too high it will loose contact with the oil, usually at high G's. This will of course damage the engine ......

2. "break in time" is a restriction on use of engine performance, usually a limit on engine revs. Not a time out for oil change.

3. I use new oil for 1st startup. Then after the engine is timed, carb rough adjusted, and run for about 30 min total, (20 mins at 2500rpms to seat cam bearings), 10 more to check for leaks and observe water temp. Then I throw away the filter and all the oil and replace with normal use oil and filter. I will change out after another 25 hours or 1500 miles or so. After that, usually each winter, I replace all the fluids in the car. I maybe put 2K miles a year on car.

4. The "Rule of thumb" is 10 pounds of pressure for each 1000RPMs with a bit higher at idle and restricted by the pressure relief valve in the pump. Most of the engines I have built idle at about 30psi when warm, run up to about 80 at max rpms, and at 2500 down the freeway the range is about 35-45psi.

5. I don't quite know what you refer to when you say "adjustable pump". Ford pumps have a spring driven pressure relief valve and you can change the point it opens with shims or a different spring. I never had to mess with that myself. Maybe you should call Roush and ask exactly how to do that adjustment. That's what I would do. Let us know what they say.
 
Thanks Howard, that was elaborate and educational. It is what the Roush papers with the engine stated. In looking up Melling pumps, it appears there is a way to adjust them, but with the pan off. I did not build the engine, so I have no idea if Roush put the pick up at the right height. I am surprised that a relatively small decrease in oil quantity already caused a major loss of pressure. Break in according to these papers is specifically stated at 3000 miles.
 
Roush data for 402AL, would appear they 'adjust' oil pressure at assy to compensate for pumping loss with cooler etc. To me that means they remove bypass plug and spring and adjust spring pre load with shim.
Always amuses me to read this stuff, dyno pulls to verify power etc then tell new owner to baby it for 3000 miles!
As engines are shipped from Roush less fluids its up to initial installer to ensure oil levels etc, your car apparently 'sat' for 8 years prior to your purchase having done a total of 21 miles, a lot of its condition will depend on measures taken prior to storage and what if any prelube precautions were taken prior to restart & your purchase
 

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Well, I'm impressed with your awareness on my specific car... albeit its feels a bit stalkish... ;). At any rate, the engine, transmission and final build in general was done at and by Roush engineers. The engine did not come shipped to the first owner. For whatever that is worth. But I do appreciate your comment about doing dyno pulls and then babying it... although I had an issue with poor seating of rings with another engine. Not being an engine builder myself, I am not familiar with the intricacies that may or may not make a difference. I'm not running a cooler, so there should be no pressure loss. Maybe that is why it's running lower pressure, since they put it together and did not hook up the oil cooler. I do not know what precautions were taken. The oil was clean. I know that. I don't know if the engine was cranked without starting it to pump oil around or if any other precautions were taken. To be honest, I'm skeptical that would make a huge difference for one occasion. But I could be wrong.
 
Stalking..ha ha. I often have to do that when replying to posts...you guys leave out vital info!!

Let me address your skeptisim.... Prior to the years of storage were the rockers removed or let off so that all valves were closed with only seat pressure on the springs, this helps prevent any corrosion in the cylinders and loads on the valve train. Was it in a dry enviroment. Rather than cranking engine over prior to restart for pre lube after storage was the distributor removed to prime oil pressure without turning the motor on the starter. You dont think it would matter on that one occasion?? How much oil do you think might still be clinging to the cam lobes after all those years..... want an indication of the load on a cam lobe/lifter on that first revolution without any oil...... hold a ball point pen tip against your desk and sit a 250/300 lb weight on the pen to push it down into your desk.... that is an approximation of the contact area between lifter and cam.... not much oil going to squeeze into that area without some help.
Now I appreciate that you probably dont know what happened with your car at that time and hopefully whoever did the work took some precautions, put it this way, if you still have all 16 cam lobes and full spec valve lift at 2700 miles your likely OK.
Well, I'm impressed with your awareness on my specific car... albeit its feels a bit stalkish... ;). At any rate, the engine, transmission and final build in general was done at and by Roush engineers. The engine did not come shipped to the first owner. For whatever that is worth. But I do appreciate your comment about doing dyno pulls and then babying it... although I had an issue with poor seating of rings with another engine. Not being an engine builder myself, I am not familiar with the intricacies that may or may not make a difference. I'm not running a cooler, so there should be no pressure loss. Maybe that is why it's running lower pressure, since they put it together and did not hook up the oil cooler. I do not know what precautions were taken. The oil was clean. I know that. I don't know if the engine was cranked without starting it to pump oil around or if any other precautions were taken. To be honest, I'm skeptical that would make a huge difference for one occasion. But I could be wrong.
 
Well then, sounds like the covers need to come off and an inspection is due. I appreciate the candor. Thanks for the advice, I've got some work to do this winter...
 

Rick Muck- Mark IV

GT40s Sponsor
Supporter
Personally I would never let oil go more than 1 year regardless of miles. Oil is changed more often based upon the breakdown of the additive package as opposed to the deterioization of the base oil itself. Plus as it goes through cold starts and never gets to real operating temps the condensation and acids build up and further destroy the oils' ability to properly protect those vital engine parts.

As has been said, oil in the bigger scheme of things, is cheap compared to lifters, bearings, pistons, etc.
 
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