460 help
Thread Starter
|
Freshman User
Joined: May 2010
Posts: 25
Likes: 0
460 help
Hi guys im new here, i have a 93 f250 with a 460 manual tranny with 116,000 miles, ive done some research on here about excessive oil usage in these motors, im going through a quart every 150 miles or so, no leaks anywhere no oil in the antifreeze but i did come across a post on here from 2004 about the intake gaskets leaking from the lifter valley and possibly using a valley pan gasket to fix the problem but no one was sure if one would fit, i found them for 87 and earlier model 460's and up to 94 on models that are RV's i was curious if there was a difference in the heads and or intakes that these wont fit the pickups? or if anyone knows any new info on this topic it would be greatly appreciated. This problem just really has me stumped and just like the older posts there is no smoke at all coming from the exhaust not even at startup but the tailpipe has a lot of black soot in it
Mountain Pass
Joined: Sep 2006
Posts: 116
Likes: 2
From: Harrisburg, Oregon
If the valley gasket is leaking oil, you'll see lots of oil out the front or back of the gasket where the seals are. If you don't have oil all over the timing cover from the front leak, or all over the bell housing from the rear leak, then your valley gasket isn't the cause of your oil consumption.
Perhaps you have a more customary cause for oil consumption? Is the exhaust blowing blue smoke? Have you checked to see if oil is leaking past the oil filter seal while the engine is running? Have you looked at the drip hole at the bottom of the bell housing to see if perhaps your rear crank seal is leaking motor oil? Have you checked whether your engine oil cooler lines are leaking, or whether your engine oil cooler is leaking?
Don't just jump to the first conclusion on a guess. There are many potential causes for oil loss. Investigate them all before throwing expensive parts or time consuming repairs at the engine.
Scott
Perhaps you have a more customary cause for oil consumption? Is the exhaust blowing blue smoke? Have you checked to see if oil is leaking past the oil filter seal while the engine is running? Have you looked at the drip hole at the bottom of the bell housing to see if perhaps your rear crank seal is leaking motor oil? Have you checked whether your engine oil cooler lines are leaking, or whether your engine oil cooler is leaking?
Don't just jump to the first conclusion on a guess. There are many potential causes for oil loss. Investigate them all before throwing expensive parts or time consuming repairs at the engine.
Scott
pedant
Joined: Jan 2008
Posts: 23,576
Likes: 38
From: EXTREME southwest CT
Welcome to the forum 93f250xl, 
That's an outrageous amount of oil.
I thought my truck at 300k losing a quart every thousand miles was bad.
To answer your question about the gasket.
In 1987&1/2 Ford went to EFI for the 460 and doing so changed the ports in the heads, as well as the intake and exhaust manifolds.
Chassis cabs and drivetrains for vehicles like R/V's over 10,000# GVW remained carbed and exempt from the same emissions laws as pickups.
Since there was no carb with a choke there was no need for a heated exhaust crossover in the floor of the intake manifold plenum to help evaporate raw fuel that would pool there.
Since there was no exhaust crossover there is no need for the turkey pan under the manifold to keep oil from splashing and cooking onto the bottom of the manifold.
The valley pan gasket was a heat shield,.... a way to try and keep the oil cool and the bottom of the intake from getting covered in carbon that could break off and clog the screened pickup in the oilpan.
That's an outrageous amount of oil.
I thought my truck at 300k losing a quart every thousand miles was bad.
To answer your question about the gasket.
In 1987&1/2 Ford went to EFI for the 460 and doing so changed the ports in the heads, as well as the intake and exhaust manifolds.
Chassis cabs and drivetrains for vehicles like R/V's over 10,000# GVW remained carbed and exempt from the same emissions laws as pickups.
Since there was no carb with a choke there was no need for a heated exhaust crossover in the floor of the intake manifold plenum to help evaporate raw fuel that would pool there.
Since there was no exhaust crossover there is no need for the turkey pan under the manifold to keep oil from splashing and cooking onto the bottom of the manifold.
The valley pan gasket was a heat shield,.... a way to try and keep the oil cool and the bottom of the intake from getting covered in carbon that could break off and clog the screened pickup in the oilpan.
Thread Starter
|
Freshman User
Joined: May 2010
Posts: 25
Likes: 0
Skucera, the problem ive heard about the intake gasket wasnt that it was leaking around the front or back seals but leaking into to intake ports on the head and burning it. i have searched this this thing top to bottom for any exterior leaks and found nothing, no dripping when its running, and it doesnt drip sittin in the driveway and there is no blue smoke. ardwrkntrk, thanks for that info, that answered my question about the valley pan gasket, i dont drive the truck that much maybe one day if we get some nice weather around here ill pull the intake off and see if theres any oil leaking into the intake ports, ive pulled the plugs and only found 3 cylinders burning oil all on the left side.
Thread Starter
|
Freshman User
Joined: May 2010
Posts: 25
Likes: 0
ok i did some more searching on the truck and i found where oil had been leaking out of the airbox and running down the inner fender i checked the PCV and its good and its def. getting good vacuum through it. I pulled the hose that goes to the airbox off the left valve cover and with the truck running i can def. feel vacuum when i put my finger over the valve cover hole, i even revved it up to about 3000 to 3500 Rpm for about a min. and still felt a good vacuum. Now i did notice the one hose that comes off the PCV goes to some electric solinoid and then to what looks like maybe a carbon canister? well the canister has a hole melted in the top im not sure but maybe that would have some kind of effect on it? if anyone else could give me a little more insight on this that would be great, Thanks
Mountain Pass
Joined: Sep 2006
Posts: 116
Likes: 2
From: Harrisburg, Oregon
I'm not too familiar with this new 460 yet (I had a '69 Lincoln Continental years ago, but that engine doesn't even seem to be the same compared to this fuel injected one in my F250), but I've had PCV mechanisms on two other engines fail, and both resulted in huge oil loss. One was a stuck PCV valve on a Toyota that sucked oil straight into the intake manifold. The other was a pair of stuck VCV's (Vacuum Control Valves) on my BMW that resulted in no positive crankcase ventilation except with wide open throttle; the rest of the time pressure built up in the crankcase and blew oil out every seal. That resulted in the loss of about one quart every 100 miles.
Like my failed VCV valves, the hole in the charcoal canister may be throwing the expected vacuum balance off, resulting in the oil you see being sucked into the intake manifold. I don't have my manuals handy to look it up, but your theory seems plausible.
Scott
Like my failed VCV valves, the hole in the charcoal canister may be throwing the expected vacuum balance off, resulting in the oil you see being sucked into the intake manifold. I don't have my manuals handy to look it up, but your theory seems plausible.
Scott
Last edited by skucera; May 24, 2010 at 11:29 PM. Reason: grammar
Thread
Thread Starter
Forum
Replies
Last Post
MEvans043
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
19
Apr 26, 2016 04:05 PM
Heston Stewart
1967 - 1972 F-100 & Larger F-Series Trucks
9
Aug 14, 2015 08:01 PM
1998Ranger25L153CID
1983 - 2012 Ranger & B-Series
3
Jan 6, 2015 01:51 AM
tjnthesky
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
7
Sep 18, 2014 10:53 PM
Brown Falcon
1994.5 - 1997 7.3L Power Stroke Diesel
42
Jun 22, 2014 10:17 AM
