I have a 1979 F150 pickup with the 400 engine. Oil is leaking from where the dipstick tube goes into the engine pan. Just from sittting in the garage for a week, I had what looks to be about 1/2 quart of oil in the drip pan I put under the truck. I went to the local parts house and they told me that there is no seal around it, and it just gets pushed into the pan. However, the guys that work there are generally idiots anyhow, so I do not believe what they say, and also that makes no sense since something must seal the spot where the tube enters the pan. They did not even look in the book to see what was there.
Can someone please tell me what seals that junction spot where the dip tube enters the oil pan.
By the way, does Ford have the dipstick tube going into the pan on all their engines? I have owned mostly GM vehicles in the past and on them the dip tube goes in the block. In my opinion, this is one of Ford's screwups.....
So, if we give you an answer you don't like, are we idiots also? Look again. The point the dipstick tube enters the pan is above the level of the oil (when the engine is not running), oil cannot leak from there.
One other explanation, albeit unlikely, is that there's so much sludge in the pan that the oil level has risen. It's not unheard of to have that level of sludge in a poorly maintained engine, especially one as old as this one. Want another possible explanation? George has an overfilled pan.
I crawled under the truck today to see what I could do with this thing. The tube has a nut around it, sort of like the end of a steel brake or fuel line. It takes a 5/8" wrench. This tells me that the tube must be flared on the end. However, the indent in the pan where this nut goes, is too small for a normal open end wrench. I was able to slightly move it with my wrench, but there is not enough space around it to get it to turn more than maybe 1/12th of a turn. I called a ford service garage and spoke with the mechanic. He confirmed that the tube is flared, and that nut needs to come out to remove the tube. When I asked about the wrench, he said that Ford makes a special wrench, but they are costly and could takes months to get it from special order. He suggested taking a standard box wrench and grinding away most of the metal around the opening, then bending the handle. He said he made his own like that. He said that removing them is a "major bitch" (in those words). He was honest and told me not to bring it in to his shop unless I can not do it any other way, because its very time consuming to turn that nut a little at a time, and he said that's at $65 an hour they charge. He went on to say that there is a good chance all I need to do is tighten that nut against the flare a little tighter. However, he said there is no way I can do it with a standard wrench. I have to either modify a wrench, or buy that special one from Ford.
I carefully checked around the whole engine, and that oil is definately leaking from where that dip tube enters the pan. It's only about 3 1/2 to 4 inches from the bottom of the pan, so I still think that the oil is that deep in there. If not, it's darn close, and the oil is being forced out while I drive and then drips down when it's parked.
Why Ford ever decided to put the dip tube in the oil pan, I will never know. Every other car I have ever worked on has it in the engine block. This is NOT one of Fords better ideas.
Come to think of it, it's a real stupid setup, because that tube most likely has to be removed every time the oil pan is removed, and since they make it so hard to remove, that makes the whole job difficult.
So the 351's are like that too, I didnt know that. I also did not know about the poor oiling and bad wristpins. I will keep that in mind. Is there anything one can do to make for better oiling, besides the obvious like changing oil regularly? As old as this truck is, I have not had any major problems with the engine other than the usual stuff, water pump, fuel pump, carburetor rebuilding, several starters, etc. The most major problem was replacing the timing chain and gears.
Not all the 351's. There are/were two. The more common is the 351 Windsor, which survived into the nineties and is related to the 302.
There was also the 351M which is identical to the 400 except 1/2 inch shorter in stroke. They are nearly identical to the 351C but have larger diameter crank bearings. They were used mostly in heavy applications like trucks and LTD's. I think the last 351M/400 style engine was produced in the early 80's, maybe 1982.
All that is from memory, so I'm sure there are additions/corrections others can make.
And the 351 M (Modified) was produced from 1975 to 1982.
So these were the same engine, except the main bearings and crankshaft main journals were bigger and the 400 had a longer stroke. I don't know if there were any other differences between the engines.
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