Got a 302" Ford in the "T" bucket. After about 400 miles the oil is pitch black. It's happened twice now. Any ideas why? Thanks
Means the oil is working, the detergents in it are picking up the trash... Clean used oil is a misconception... Posted using the Full Custom H.A.M.B. App!
I treated an engine once with a small tube of a Moly / Graphite product. I guess it was good stuff, but it turned the oil black in short order after each oil change. Forever. No matter how many times I changed my oil and filter, the "flash" to black never stopped. Perhaps your motor had a similar treatment in it's past life? After the first few times, I never worried. But what pissed me off is that it no longer let me see the oil slowly turn brown as the miles went by after each oil change. And since the engine had some small air cleaners with sponge elements, I was always pretty keen on monitoring the oil's condition. Gary
In a similar situation, a burnout in a large air conditioning system for a building, three oil changes in rapid sucession is considered a clean out.
Running too rich perhaps? Excessive blowby? Possible rings not seated yet? I was always told, if the oil turns dark, it means it's working. I also recall using non-detergent oil for break in oil, but not sure about that one.
Was moly lube used as assembly lube ? At any rate if comp. and oil pressure are good drive it and see what happens .
Funny Ive had the same issue after I rebuilt my 360. I have put about 20K miles since rebuild and still just as black after a few hundred miles as when It was rebuilt and no moly lube was used as mine. I dont think the "because its working" answer is correct when you have brandnew engines that can go 8 thousand miles before looking the same dark color as 300 miles on the same oil.
Send a sample to a lab and see what's in it. Doesn't cost much, I used to do it with trucks and heavy equipment.
Not running hot at all . Good radiator and fan. Even though it's a "T" bucket. So I'm lucky there. Running an Edelbrock 600 carb. So now I think it's the EGR and too rich. I always thought the 600 was too much carb .
I think it's been off the market for awhile now but you don't happen to be using Duckhams Q oil do you?
Black oil usually means gasoline in the oil from running rich. Is it thin and smells like gas? Try lighting the dipstick with a match or lighter and see if the oil burns.
Years ago I had a similar problem. Turned out to be a bad fuel pump. The pump was letting fuel go into the pan. The clue was the smell. Replaced the pump and the problem went away. Best of luck. Matt
So, assuming it's not fuel (you should easily smell it on the dipstick if it is) I'll throw this out there. Cam lube. The Isky cam lube I used was graphite dark. I imagine when I start the engine I will have a significant amount of blackness that might stay for an oil change or two. Also, it's a fresh rebuild. Lots of things going on, lots of metal getting seated in. Blow by, etc. While it may not be too common, it's not anything to be worried about at the moment. If it wasn't meticulously clean, the oil could just be breaking loose the residue that didn't get cleaned out as well. I'm amazed at what some engine builders will put together and call fresh. Too many people don't take the time to clean oil galleries and such and it gets knocked loose on start. Change the oil since it's time anyway and see what happens. If it were me, as long as it didn't smell funny, have tiny metal "glitter" in it or turn milky, change the oil out now instead of waiting to 500 miles and just run fresh oil.
I had this happen on a fresh engine. Turns out after I rebuilt the carb, all is good. It was running way rich!!!! Now even between 3,000 oil changes it is just golden color. I would fix the carb before you ruin your engine.
You might want to take a look around here--- http://www.bobistheoilguy.com/ I use Valvoline Multi Blend,5W/30 (part refind,part syn) in my daily '04 GMC 5.3 engine. After 3500 miles,the oil is red,,,not brownish red,or tranny fluid pink,,but red. They told me it was normal with multi blends,& I believe them. You might also try one of these & see if it changes your situation http://www.shopfiltermag.com/index.php
Oil turnig black in 400 mile is from poor combustion. Think of black soot when you run rich. Raw fuel turns black which also thins the oil that is on the cilinder walls. Then the oil and and unburned fuel (black sooty wet gas) leaks past the rings as it also thins the oil layer that is suppose to seal the rings. Buy a cheap wide band O2 sensor and you will see a very rich condition. Hopefully you haven't washed out your rings and bearings at this point.
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