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I am wondering if anyone can give me an idea why my 390 is blowing the gasket off my oil filter and putting all my oil in the driveway. Someone told me that there is a check valve on the back of the block that is probably clogged and that to get to it, I have to drop the tranny. That is not a problem, but before I do that, I was hoping someone might have other thoughts.
Thanks for your help.
Welcome to FTE GunnerRob! The check valve is in the oil pump (oil pressure relief valve). I'd just replace the oil pump. Raise the engine and support it with 2x4's, loosen the pan, reach in and drop the oil pump pickup and oil pump, slide the pan and pump out. Messy PITA job! Better if you have it on a hoist! Even better is if someone else will do it for cheap.
William in Atlanta has retired to St. George Utah!
sorry about your luck
william is right you need to replace your oil pump. i did this a couple of months ago when i ran my oil out. smartest thing to do is talk someone else into doing it. not a fun job. wouldn't drive it far
G-Rob, before you drop the oilpan and try a new pump, lets try some simple stuff first, just in case. I have seen some oil filters 'grow' when the oil was cold and the engine was just started....but never saw the filter leak at the seal. What kinda filter do you have ? Trying another one, or another brand, seems cheap and easy before you go and take off the pan. Is the surafce where the oilfilter mounts to clean and smooth ? If the mating surface on your oil fliter adapter was nicked or gouged, it might leak. And the oil fliter adapter is a heckuva lot easier to change than the pump. Is the threaded pipe thingy all the way into the adapter ? If it weren't, you might have trouble getting the oil filter on all the way, and you'd have .....leaks. Usually when one of the relief valves gets stuck, it sticks open. Most FEs have the relief valve in the pump, but there are a few older models that had another one in the back of the block...what year is your block ? You might also try to clean the relief valve out with an oil change. Add 2 or 3 quarts of 'dexron' or 'mercon' tranny fluid to the oil and drive it around ( or just let it idle in the driveway ) for about an hour. Then drain and refill with whatever your normal oil is, and see if you still have the problem. The auto tranny fluid is just 30 Wt oil with LOTS of detergent in it. Mybe you will get lucky, and not have to take off the pan. DF
Thank you for your reply. I have now tried two new filters, same result. The surfaces are all smooth and there is nothing wrong with the adapter. I tried running some rislone through it yesterday with a new filter, but as soon as I started the truck, the pressure pegged my gauge (80+) and I had five quarts on the ground. It is not a leak, the pump is pushing the oil right past the filter gasket. The relief valve at the back of the block is my suspicion now. I have a friend who's dad is referred to as "Dr Ford". I am going to his house today to look at a 390 block to locate the valve. I cannot find any reference to it online.
I would try to clean the valve as you suggested, but as soon as I start the truck, I am pumping oil out of the filter, so that will not work. I foresee pulling a tranny in my future to get to that relief valve.
I will let you all know what happens. Thanks again!
Rob, in all likelyhood, you don't have an oil relief valve in the back of the engine. Only the early ones had those, like '61s and older, IIRC. Some 427s have a valve at the back as well. But Ford started putting the valves in the oilpump in the earky 60s. Even if you have an older block with the valve in the back (it is just under the cam, I think ) you could drop the oilpan and install a newer style oilpump, with the valve in it, and it would not matter if the valve in the block worked or not. DF
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