View Full Version : Warning! All your engines are going to die!
FSJ Thing
12-09-2006, 06:35 PM
Remember a few years ago, when everybodies cam was dying shortly after break in? Mostly it was the K8600 cam (I had one too, I just swapped it because I was afraid it would die too), but I think that's just because it was cheap and available at that point in time.
Well, I just picked up the HOT ROD special issue "Do-it-yourself Series ENGINES", and it told me something I wish I'd have known before I spend money on TWO perfectly good flat tappet cams.
All the OEMs are making engines with roller cams now. To "improve emissions" they got together with the oil companies and mad ethem take this stuff called ZDDP out if it, because blow-by can put it in the exhaust and it destroys O2 sensors and catalytic converters.
Unfortunately for US, ZDDP is the stuff that keeps flat-tappet cams from going flat! It's some kinda zinc and phosphorus combination that sticks to the lobes and gets destroyed over and over to protect the metal in the cam and the lifters (it's tougher than just an oil wedge, the ZDDP can withstand 200,000 psi).
Personally, I think it's MAN trying to get rid of our beautiful Jeeps so we have to go buy NEW cars! That's why they did it, emissions my left butt cheek!
So, when you go to rebuild your engine, better get a roller cam, flat tappet cams won't cut it anymore!
Matt
Millerluck
12-09-2006, 07:06 PM
Yeah I read that too. I did have a high milage stock cam go flat. Then put in the Summit 8600. Had no problems.
I'm gona try and swing past the GM dealer and see if they have any of that cam prelube. Part # 12345501
Ive been running 4 qts Valvolien 10w30 with 1 qt moble 1 10w30
Now that is been colder. 4 qts 5w30 Valvolien and 1 qt moble 1 5w30
Larry Miller
FSJ Thing
12-09-2006, 07:19 PM
Yeah, I'm a royal purple fan, but I've heard nothing but good things about Mobil-1 too. I'll be running in my 401, once it's all buttoned up, on dino oil but I need to find out what ZDDP additives are compatable with royal purple after it's run in.
Also, appearantly that's all that cam break in additive that you're supposed to add to your oil when breaking in a cam is, straight ZDDP, so for all of us with high milage hyraulic cams, we can get by by adding cam conditioner to our oil all the time. Also, racing only oils and diesel oils still have ZDDP in them, so those are other options.:thumbsup:
Lindel
12-10-2006, 06:49 AM
My experience with cams going flat were always the stock cam at about 175,000 miles. Never had a problem with either of the Summit cams I used. I'll probably go back with a Summit in my wife's 88 and again when I pull the J-10 engine and rebuild it for a spare.
Good info to know tho, thanks.
Rogue
12-10-2006, 11:59 AM
IIRC Bulltear's AMC oil has all them there special ingredients
andy d
12-10-2006, 12:42 PM
BITOG is your friend, the new oil formulations are being regarded with skepticism over there . I dont really pay attention, but there are several, oil additives you can buy with ZDDP in them. Follow the directions, over use will harm cat.is about the only issue. IIRC, Valvoline, S.L.O.B. is a good'un
FSJ Thing
12-10-2006, 01:34 PM
My experience with cams going flat were always the stock cam at about 175,000 miles. Never had a problem with either of the Summit cams I used. I'll probably go back with a Summit in my wife's 88 and again when I pull the J-10 engine and rebuild it for a spare.
Good info to know tho, thanks.
Totally, I don't think there's anything wrong with summits cams now. I just remember that about two years ago, right after all the oil companies took ZDDP out of the oil, everyone with a Summit cam had it go flat. I think it's because everyone just happened to be buying that cam at that time because it was a good grind at a great price. Nothing wrong with the cam at all, I know that now, after I replaced it with a Mellings MTA-1. And it's not just our community either. Reps from Comp and Crane both said in that magazine that they've seen more failures in the last three years than they have in the three decades that preceeded it! Across the board, Chevy, Mopar, Ford and imports included! Without ZDDP in our oil our cams will die. A properly broke in cam will last longer without ZDDP, but without the ZDDP barrier at the metal to metal interface, the metal is going to take the wear and the cam will die.:(
So without ZDDP in our future oil changes, ALL of our hydraulic cams, new, old, Summit, comp, crane and even lunati are at a huge risk. Anybody planning a rebuild in the near future would do well to allot funds for a roller cam.
That's good to know about bulltears oil too. Do they have any plans to start making a batch based on synthetic stock?:)
DanHS
12-10-2006, 01:53 PM
Hmm, this is good to know. I already use 15w40 diesel oil in the GW now, I suppose I'll have to go buy the additive from now on for the other cars, I never heard of this before, and certainly never had any problems, but I'd certainly hate to have my cars start dying on me from dead cams.
drlocke
12-10-2006, 04:51 PM
Ditto on that 15W40; I'm using Shell's RotellaT and "Truckela" by another company whose name I don't currently recall. Good for the Mercedes, good for the other engines, I find. Good quality oil that keeps the soot and grime in suspension very well.
As for camshafts IIRC there was a whole raft of engines released on the market a few decades ago with peanut butter camshafts which caused a lot of trouble--GM perhaps being one of the chief offenders on such count.
Thank God for the some of the better aftermarket ones, which I've constantly heard over the years are properly processed to the appropriate hardness and durability for such service.
Serious Johnson
12-11-2006, 11:10 AM
Well I'll be durned -- sometimes you do learn something new! I wonder if that particular bit o' stuff or equivalent is in Mobil-1. I ran Mobil-1 0w20 or 5W20 in my hotrod 360 (K8600 cam), which frequently saw 6,000 RPM under heavy load, for a couple of years and some 25,000 miles, and that thing had a fair bit of valve spring pressure.
Are roller cams even available for AMCs?
S.J.
jeepsr4ever
12-11-2006, 11:21 AM
This has been going on for over 7 years now...LOL
Seriously!
http://www.bulltear.com/catalog/product_info.php?cPath=21_35&products_id=110
ultimateamc
08-16-2007, 07:48 PM
Just to let everyone out there know, Diesel formulated oils still have the additives for flat tappet cams. I personnally own a 97 dodge ram( work vehicle) with 234,000 miles on it and have never touch the engine or trans except for lube changes and filters. (does have a factory roller cam though) this truck has been run from the first oil change with MOBIL ONE and does not use or burn any whatsoever... this truck is used in a multiple of ways not some sissy show piece. starts at minus 20 degrees with no moans and groans as with regular oils often do. more impressive then the engine holding up is the transmissions in these trucks weren't stellar in the 95-97 model years. this has had sythetic trans fluids from the beginning also. Synthetics are in my opinion worth their money and more. :banghead:
shepherdskeep
08-16-2007, 08:07 PM
One word - LUCAS :D
Don S
08-16-2007, 08:55 PM
..
This subject was just covered a few days ago... so for more info and links;
http://www.ifsja.org/forums/vb/showthread.php?t=73604
Have a good one while you can still laugh about it.. Don S..
If something I’ve posted on the Internet offends you please ignore it.
If you don’t know how to ignore something on the Internet e-mail me … and I’ll demonstrate.
DieselSJ
08-17-2007, 01:09 PM
Just to let everyone out there know, Diesel formulated oils still have the additives for flat tappet cams.
Well, sort of. With the new API CI+ spec, the zinc levels in the "diesel" oils are being reduced also. When the CJ spec is released, zinc levels will be even lower.
710 Burner
08-18-2007, 09:43 PM
They all die eventually, especially if I drive them. :eek:
2003 mcs
08-19-2007, 10:21 PM
Wouldn't doing an UOA help? You can tell if the oil is working, and if there is excessive wear metals in the oil....Well help in knowing when the engine will give up.
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