So I'm in the process of getting my Mav back on the road. I pulled the engine and tranny to put headers on, this led to finding a rear main seal leak. So I pulled the oil pan. Upon doing so I find the bottom of my oil pan covered with a sludge of oil and debris and I'm thinking oh crap my oil pan is full of metal chunks. I take a closer look and discover it is pieces of black plastic or rubber and then I'm thinking oh crap my oil pan is full of plastic crap. So anyhow I pulled the valve covers and found a few more pieces of the plastic/rubber around the lifters, but everything looks good. I have looked at lifters, springs, mains, rods and pistons from underneath and can find nothing out of the ordinary. So I am stumped as to what all the junk in my oil pan is from. Any ideas? Most of the pieces are small with some a little smaller than a dime, but there is a ton of the stuff.
valve guide seals? that would explain why theyre all through out the motor and the broken round piece in the third pic sure looks like a half of one. clean it all up and put new seals in and go for who knows how many more miles if the valves are still in decent shape. otherwise rebuild the heads with new valves and would be a good thing to have all new seals and new springs. assuming the heads arent sucked or just plain worn out. signs of high mileage and age edit: after looking again I believe thats only part whats going on I think the rest of it is just burnt oil from years of not changing the oil often enough if you take the heads off the pistons will prolly be pretty blackish gold colored from oil burning on the pistons and carbon build up. really dont know without tearing the engine apart more. I would start by checking the valve guide seals though
I'll take a look tomorrow. Block is stock 73 302 and I believe heads are stock as well. Motor ran like a raped ape before I pulled it. I have been thinking of putting some different heads on it, maybe E7's, found a cheap set on craigslist.
Yep valve stem seals and maybe pieces of the nylon toothed timing gear, just found both in the pan of my 302... There will also be pieces in the oil pickup screen that if not fully cleaned can lock up the oil pump... Would be a really good idea to check the upper timing gear, should be ale to see it from bottom... Mine had steel gears, pieces were from original gear that had been replaced at some point... If the valve stem seals(really they're deflectors or umbrellas)not replaced, the engine will be a heavy oil user...
Well today I sifted through the debris in the bottom of my oil pan as I got it cleaned out. I believe it is indeed the valvee guide seals as stated above, which leads me to believe this engine has probably never been rebuilt and if so it has been a long time. I did happen to find something else in my oil pan, something metal. Not sure what it is, anyone have any guesses? Also, how can I tell if my timing chain is shot or has ever been replaced?
If the upper timing gear is steel it's no doubt been replaced, if it has nylon teeth it should be replaced as it will fail... My 302 has a upper steel gear but the teeth are badly worn so has a lot of miles, apparently was replaced when the '78 heads were installed... I only went into mine to get the parts I need for the 5.0 swap... You can get a idea how loose the chain is by rotating the engine forward then backwards slightly to see how much free travel there is before distributor rotates...
no one really knows if your motor has been rebuilt but you can see some work has been to with the heads that gasket for the valve covers is definitely not original equipment and the nuts on the rockers are locking nuts with the plastic insert the original nuts werent like that they were just plain old nuts.. its been a long time since anyone has done anything to the motor though as you can tell through all of the sludge and burnt il on the valve springs. it looks like they repaired whatever went wrong and kept on neglecting it. I got lucky (kinda) with my motor everything was so clean and fresh. double roller timing chain high volume oil pump but heres where the kinda comes in the motor was bored out 40 over and either they put on stock rings or the new rings have failed already. we did a leak down test and air comes whistling out of the oil dipstick tube. so its time to tear it all down and rebuild it again. Ive never seen anything round like that piece of metal you found . the only thing I could think of that that might be is a small part of your piston. maybe the bottom side where the connecting rod connects maybe it hit and broke off? I would imagine there has to be some super high rpms or alot of wobble for this to happen but Im no expert
The mysterious history of an engine, no telling what it has been through in the last 40 years. I have no doubt it has been run hard. I scraped off a coating of about 1/2" of burnt rubber under the rear quarters from some pretty serious burnouts in it's past. I was hoping to not have to get to deep into this block as I hope to some day put a crate motor or 347 in it. I will probably just clean it up, put new valve guide seals on it put it back together and hope for the best for a while. Here is a top view of the piece of metal I found in my oil pan, its' a little smaller in size than a dime.
if all you want to do is stretch the life out of the motor clean up the heads with new valve guide seals clean the crap off of the valve springs and clean the bottom end of the motor as best you can with a clean paint brush and some gas then put it all back together with a good oil like mobile one and you should be good for years as long as you change the oil regularly. as long as you dont beat on it like it was before itll hold together until almost the end of time. an inexpensive 347 can be built out of that old block for around 1500 in my area if you do all of the assembly yourself
The metal piece looks like the plug located at the back of the lifter valley, it is visible with the intake removed. From the looks of your oil you are leaking water into the engine somewhere.
The crud that accumulates over time in the bottom of a oil pan often has a milky look to it, I bet the engine is fine... If fact that pict shows almost exactly how my pan looked and it had almost new oil(been in there a prob four months but never driven)... Drained that oil into a clean pan and it was still translucent, used it and filter in my beater '96 F-150... I agree with the mystery part being galley plug, but if one were missing it would not have oil pressure...
Good eye on the water in the oil. It did indeed have some water in the oil at one time. When I first picked up the Mav, the PO had a high rise Offenhauser intake on the motor, and it apparently wasn't sealed very well. It also did not have a hood any more because he lost it while driving. So after a rainstorm one day I noticed the oil was milky, it was at this point I moved the Mav into my shop where it has now been over two years. I changed oil and ran a cleaner, then changed oil again. I never ran the motor more than a couple minutes with the water in the oil. Hopefully there was no major damage done. I have since put a new Edelbrock performer rpm aluminum intake on, but did not notice the oil galley plug missing. Guess I will pull the intake to double check. I also am going to replace the oil pickup since the screen is packed with valve guide seal carnage. Should I replace the oil pump as well?
it wouldnt hurt to put in a new high volume melling pump while you have it apart. who knows how old that pump is if it has ever been changed.
A HV pump is basically going to rob HP, there's really no need for 60 psi at 2K rpms, these days many builders recommend against them... Both my 331 & 306 are getting a std Melling pump... The 331 will be raced and beat on like a red headed stepchild... Now if clearances are "loose" due to wear, they aren't a bad idea to try for extra miles... Of course they should be used in race only engines with wide clearances...
Well there may be some wear. I pulled the end cap tonight and replaced the rear main seal, so you can see from the attached photos there seems to be some wear. Bottom end has probably never been touched. I'm just gonna button it up, fix what needs fixed and run it this fall. Then maybe this winter pick up a roller motor or pull and build the current one. I just want to get it back on the road and be able to drive it before the snow falls.
