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wagone
12-12-2005, 07:18 PM
Recently Paul (aka pszikszai) commemted on this forum concerning oil consumption on his 259 rebuilt V8. Nate (N8N) responded with, among other things, a suggestion on restricting oil flow to the rocker shaft in case the shafts or rockers were worn and dumping excess oil on top of the heads with the possibility of this oil being sucked down the valve guides. My V8 has been bored and all new parts used but the rocker shafts were NOT rebuilt. My engine, though fully broken in, continues to burn oil at the rate of 500 miles per quart. Oil pressure is 50-60 pounds hot and at anything over 1500-2000 rpm. When I get my garage heated or, more likely spring arrives, I intend to do a compression test and or leak down test. If the problem is not with the rings and I wish to restrict oil to the rocker arms what advice can be given? More specifically, can the right rear (and also left front) rocker shaft bracket drilled hole be resticted with a machined orifice made with an interference fit and fitted in the drilled hole? If so what diameter should the orifice be sized to? Any advice from the experts would be greatly appreciated. Oh, my rear drain holes through the heads are open and even at idle if a breather is removed to look down on top of the head a stream of oil can be seen to flow to the rear of the head--is this much oil normal?
wagone and Avanti I

DEEPNHOCK
12-12-2005, 09:23 PM
I have a 289 with a custom setup that the oil can be completely shut off to the rockers, if I want. Used to do it for drag racing, though it was a useless gesture.
This, by itself will not solve your problem.
Are you triple sure you are sucking oil down the intake guides?
That is fairly easy to diagnose.
When you say 'burning oil', is that really what you mean?
If it is truly on the heads, then it would be noticeable on decelleration. If it were rings, it would be on accelleration.

Chasing demons without good diagnosis can get expensive.

If you want to just check to see if your heads are indeed the problem, just swap the rocker stands from end to end and run the engine for an hour, and you will have your answer, but I doubt seriously that this is your problem. For the same time and effort you could pull off all your valve springs and retainers and install Ford umbrella seals and get 85% of the oil off your intake guides.
Just an opinion, mind you....
Jeff[8D]



quote:Originally posted by wagone

Recently Paul (aka pszikszai) commemted on this forum concerning oil consumption on his 259 rebuilt V8. Nate (N8N) responded with, among other things, a suggestion on restricting oil flow to the rocker shaft in case the shafts or rockers were worn and dumping excess oil on top of the heads with the possibility of this oil being sucked down the valve guides. My V8 has been bored and all new parts used but the rocker shafts were NOT rebuilt. My engine, though fully broken in, continues to burn oil at the rate of 500 miles per quart. Oil pressure is 50-60 pounds hot and at anything over 1500-2000 rpm. When I get my garage heated or, more likely spring arrives, I intend to do a compression test and or leak down test. If the problem is not with the rings and I wish to restrict oil to the rocker arms what advice can be given? More specifically, can the right rear (and also left front) rocker shaft bracket drilled hole be resticted with a machined orifice made with an interference fit and fitted in the drilled hole? If so what diameter should the orifice be sized to? Any advice from the experts would be greatly appreciated. Oh, my rear drain holes through the heads are open and even at idle if a breather is removed to look down on top of the head a stream of oil can be seen to flow to the rear of the head--is this much oil normal?
wagone and Avanti I


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wagone
12-12-2005, 11:04 PM
Jeff: Thanks for your comments. Only two major ways oil can be lost from an engine and this one (unlike most Studes) does not leak oil so, by process of elimination, it has to be burning it. But no, I certainly don't know for sure that it is going down the valve guides. I only know I've got something over three big ones in the overhaul and I'm burning oil at the rate of 500 miles per quart. Short of a compression test or a leak down test I know of no other way to determine where the oil is going--it never has, that I can detect, smoked on deceleration but I've seen a little smoke on acceleration, occasionally. The plugs had shown evidence of oil fouling but recently that seemed to be clearing up. However, just the other day I drove 170 miles to our new house and used about 1/3 of a quart in the drive. Did NOT make me very happy. The overhaul included moly rings and hyperutectic (spelling?) pistons. I cannot recall what these V8s did for oil mileage when new--it seems as though they were not great on oil usage--maybe 1000-1500 miles; at least I'd be very happy with that. I'd asked Ted Harbit about positive valve guide seals before the engine came down and he didn't believe it to be necessary and (in my humble...) you need a little oil down the guides and don't want to seal it all off. In any event I'm not real happy and hence open to suggestions.
wagone and the Avanti I

Alan
12-12-2005, 11:33 PM
1 quart per 500 miles is not bad for a fresh rebuild with moly rings, they take a little while to seal sometimes if they don't like the cylinder wall finish. But the oil river past the breather hole. Almost sounds like a plug came out of the end of the rocker shaft. For shure those stock type valve seals can't keep that kind of oil out of the chambers.

whacker
12-13-2005, 12:03 AM
If you are actually burning that much oil, you have to be able to see evidence of it. Is there a black, sooty deposit around the end of the tailpipe? Is there oil fouling the paper air cleaner? Or do you see a puff of smoke when you start, or accelerate, or decelerate the engine? I would look at the crankcase vent system real carefully.

wagone
12-13-2005, 11:47 AM
Note to Alan and Whacker (and any others out there): Alan, I have about 4000 (yes, four thousand) break-in miles on the engine.....so, the moly rings should have sealed, by now!? Yes, I've thought about a missing plug on the rocker arm shaft as a possibility. So I may have to remove the shafts and investigate that. I told the shop that did the engine I didn't want the shafts disassembled (unless they FULLY understood how the parts were to go back together) and they said that they wouldn't take them apart. Of course, that doesn't mean they weren't apart at some earlier point in the engine's life. The funny thing is that I'm quite sure the stream of oil flowing back to the rear of the engine is visable on the LEFT head where the breather is at the FRONT of the engine before most of the cylinders can contribute to the flow from large clearances at the rockers. Which could imply a missing plug at the front of the shaft? I'm not familiar with the shafts but there would need to be a plug at at least one end of each shaft, but I don't know which end (the factory manual does not seem to address these plugs?).
Whacker: The exhaust pipes are sooty black and the engine is NOT leaking oil (I'd trade an oil burner for a leaker any day of the week). The engine only rarely shows any oil burning out the exhaust and then only when you get on it hard. There is no oily residue in the air cleaner (it is an R2). The PCV system appears to be stock and the valve is free (the system IS stock, but I cannot tell if the PCV valve is stock but it appears to be).
I intend to check for the plugs as noted above. Any advice as to which end of the shaft they should be on and what to look for would be appreciated--any mechanic who would leave those out on an overhaul would have to be a real idiot, however. I gave a copy of the engine portion of the shop manual to the shop that did the engine, but it is anyone's guess as to whether they consulted it .
wagone and Avanti I

Roscomacaw
12-13-2005, 01:50 PM
Talking about that visible "stream" of oil - it would depend on how MUCH of a stream we're talking about. Since the rockers are constantly being fed oil, there's gonna be a continuous flow of some degree. But I don't think you could have much oil pressure if one of the plugs was missing in a rocker shaft (and there IS one at each end).[:I]

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wagone
12-13-2005, 05:53 PM
Yes Mr Biggs, I've thought too, that if a plug is missing that should have a fairly significant negative effect on oil pressure and this engine doesn't exhibit that sympton. Guess I'm looking or grasping at simple solutions to a problem which in reality is a bad set of rings or a poor bore job. I'm not a happy camper at 500 miles to a quart of oil! But the stream of oil does rather surprise me--now at high rpm it wouldn't be so, but at idle? I told the shop that Studebaker V8s had a reputation for hard blocks (looking at the possibility of a poor bore job) and asked if that could be a concern in their boring operation and their answer was an emphyatic NO. But I'm still stuck with an engine which LOVES oil. Someone told me after this problem arose that some Stude V8s were this way (burning oil) from the factory and the answer was to be patient..but I'm not holding my breath on that possibility. Maybe I should block off the radiator and run the crap out of it, get it hot, and see what that does....no, I couldn't do that!
wagone and Avanti I

whacker
12-13-2005, 06:21 PM
You say the exhaust pipe shows black soot, but you only see smoke at acceleration. That pretty much proves the oil is burning, and by logic, that it is burning pretty steadily, more when you get on it (I assume that isn't real often). I'd be looking real hard at that crankcase vent system. The valve may be good, but the hoses may be plugged somewhere, or it may be hooked up wrong. If you pull the valve, does it look oily inside, like oil is going through it? It should look used after 4000 miles, but it shouldn't have oil running out of it. A clean, new looking valve would be bad, a real oily valve would also be bad. The next test would be to pull each spark plug and check the color on each one, to see if you are looking at a bad cylinder. Next do a compression check, to see if there is a single or more bad cylinders. You should be able to tell a lot from this series of checks.

Transtar56
12-14-2005, 12:53 PM
Whenever Ive had an engine using that much oil,(Stude or brand-X), the plugs would be so oil fouled after 1k miles Id have to pull them and clean them.
What Im saying is ,with that much oil burning,your plugs should be real sooty.
Have you experimented with any different brands of oil?
I use Shell Rotella diesl rated 10-W-30 in all my Studes,and have noticed on occasion,when Im caught on the road without any oil with me, I have bought a brand-x jug and tipped'er in.
It might just be my imagination,but I could swear that quart will dissappear quicker than the Shell.
I don't think,and have never heard that Studebaker V-8's were any more prone to oil burning when new than any others.
Remember,in the days our engines were designed, most only had a partial filter,if one at all. The Studebaker owners manual for my 60 Hawk recomends changing the oil every THOUSAND miles,and more often under "adversre conditions".
Mabey a few more miles and you'll be up to 1000 miles/quart, which is getting to the OK zone.

jackb
12-14-2005, 06:08 PM
I'll make a couple of statements, then see what you all think. 1st...I have "never" owned a Studebaker that did "NOT" burn and leak oil. I've had many different engines too....224, 289, 259, 170, 226,..some of these were fresh rebuilds, and some were low mileage originals (224 had 37K miles and the 170 OHV had 53K. Also, with the exception of the 224 & 226 w/OD's....I've never gotten better than 15-16 mpg. I have squeezed out 18 mpg in my fresh 289 once in the 64' raggie, but it burns & leaks oil at around 1000miles/qt.....I've always used cast iron rings and never saw good oil sealing til around 5K+ miles. I doubt you'll see any oil improvement with those moly rings for around 10-20K miles. When I rebuilt my Champ 289 a few years ago, an old Stude mechanic came by and told me to break-in the new rings in the truck by going out on the highway and drive 70+ mph for 30 or more minutes.....I wonder why he said that.....? We all like to think that our vehicles are better or best....but really...why do think Studebaker marketed STP ??? BEcause their engines, especially the 6's burnt oil !!!!!

whacker
12-14-2005, 06:24 PM
My 232 (that has been bored to 259) does not burn, and has never burned oil. The cast iron rings seated in less than 1000 miles. It does leak a little at the front seal, but that's it.

GTtim
12-14-2005, 11:41 PM
If the rocker arm shafts are suspected of having a loose/missing/damaged plug, wouldn't it be fairly easy to remove the valve cover, start the engine and see just what is going on? I've replaced those plugs and it seems to me that the chance of damaging one when it is being put in is a distinct possibility.
Tim K.

Alan
12-15-2005, 12:00 AM
Best thing to do is take an old valve cover and chop some windows in it so you can adjust the valves and see how the oil is flowing with out smoking up the neighborhood from oil on the headers.

gordr
12-15-2005, 04:10 AM
I definitely have experienced oil consumption caused by excess clearance on the rocker shafts. This was on my then daily driver, a '63 Wagonaire with a 289. It had had fresh rings installed in the original bores, with a hone job, and fresh main and rod bearings. The engine ran well, but at 60+ mph on the freeway, it'd start to smoke, and then oil pressure would rapidly become erratic, dropping to near zero. Stop the car, and I'd find fresh oil all over the firewall, particularly on the right side, where the breather vent is near the back of the head. Virtually ALL the oil in the crankcase was finding its way to the heads, quite overwhelming the capacity of the drain ports at the rear of the heads.

After stopping, the engine oil pressure would recover, and if I stayed below 60 mph, the heads didn't fill up.

So I went through my stash of used parts, and found a less-worn set of rocker shafts, and installed them, which is a pretty easy job, after all. Problem solved. I got many, many more good miles out of that engine.

In the case of a fresh rebuild, with all the oil clearances at spec,with the EXCEPTION of the rocker shafts, where is the oil going to go? It will follow the path of least resistance, will it not?

I'd certainly be suspicious at least, Wagone, that indeed you do have a problem with oil accumulating in the heads. Also, if for any reason, those new rings have not seated properly, the excess crankcase pressure will try to reach the atmosphere, and one route it will take is the drain holes from the valve area of the heads to the crankcase. So oil trying to flow down is meeting blowby gases coming up. Just adds to the problem.

I guess the right cure is to install new rocker shafts, and new bushings in the rockers. I don't like the idea of restricting the oil supply to the heads; any particle of carbon, etc., could entirely block the flow of oil to one head if it lodges in the restriction. I think the mext time I tear into a V8, I'm going to try welding up the oil holes in the rocker shaft, and then drill through the weld with a tiny drill to create a metering orifice at each rocker. It'll be in the nature of an experiment. (and if it doesn't work out, it can be undone without a complete teardown of the engine)

Gord Richmond, within Weasel range of the Alberta Badlands

Alan
12-15-2005, 11:41 AM
Gord; Just take a 1/8" taper pipe plug and put in the rocker shaft stand and drill a .020-.030 hole in the plug then if you get any crap in the hole just pull the plug out and blow it out with air and put it back in again or if you don't want just leave it out, no dammage done except for threads in the stand.

casey
12-15-2005, 02:43 PM
When I rebuild a 259/289 I always add extra drainage to the valve covers. I fabricate a 3/8" steel elbow, then drill matching holes in the back of the valve covers and weld my little elbows in. Then I weld little receiving tubes into the back of the valley cover. And then the heavy duty hydraulic hose in between. Definately not original, but I just don't want to have to worry about oil accumulation.

gordr
12-16-2005, 12:09 AM
Alan, my reasoning on the optimum location for an oil restriction goes like this:

Originally, the engine had full pressure to the rocker shafts, and the rockers were a close fit to the shafts, so pressure was retained by the new, tight oil clearance there.

Over the years, the shafts and rockers wear, and the clearance opens up substantially. The pump can keep up (too well, maybe!), and in a worn engine the shafts remain pressurized, but a huge volume of oil is spraying out around all the rocker pivots.

Now, suppose I install a rocker shaft modified such that the oil hole to each rocker journal is restricted to say, .020", instead of the .080 or so they are now. That will cut the total flow area down to 1/16 of what it was originally, but the rocker shaft will remain pressurized with oil, and a little oil will find its way to each rocker journal.

Now, let's try your approach. I install a restriction in the front rocker stand where the feed from the block meets the rocker assembly. Again, I reduce the total flow area to 1/16 of what it was originally. But, downstream of that restriction, I still have worn rockers running on worn journals. A trickle of oil enters the front of the rocker shaft, and runs down the bottom of its interior (remember it's on a slant). At each oil hole it reaches, some will trickle away, Is there any guarantee that there will be any oil at all reaching the rearmost rockers?

Both approaches will solve the immediate problem of filling the heads with oil. But I think my approach offers a better guarantee of even distribution of that reduced oil flow.

Perhaps I am obsessing over nothing.

Gord Richmond, within Weasel range of the Alberta Badlands

Alan
12-16-2005, 01:10 AM
No problem Gord. What ever works for you and keeps you happy. Back in the 60's I took an engine to C&T Automotive, gave them some big bucks at the time to assemble the engine for me because everybody said that I would have more power if they did it. Put the engine in my 53K and took a trip to San Diego to put some miles on it before Sunday, half way there it started making noises. Had to have it towed back. They put the rocker stands with the oil hole in the wrong spot on the shaft. Last time I had anyone rebuild anything for me for Studes. The mechanic there told me, I put them together just like any other Ford Y block. So I know they will run for a couple of hours just on the assembly lube.

wagone
12-16-2005, 10:26 AM
Alan, of course your experience with the shaft stands not going back in the right position and hence no oil to the rockers is EXACTLY why I told the shop that did my engine not to touch the rockers (not to disassemble them) for fear that they wouldn't reassemble them correctly.....Murphy is the only guy I ever "knew" who was right all the time. Gordr would appear to be right about restricting flow at only one point, the rockers may easily not all receive a portion of the restricted flow. When I discovered that my new $3000 engine was still burning large amounts of oil I went back to the shop that did it (of course). Not to give them I bad time but to find out whether they had any ideas or were interested in helping (they assembled the engine for me also) with the situation. AT that time I asked them about removing the intake manifold to check and see how much oil was in the intake ports and on the back of the intake valves....for what reason I don't know but they didn't think much of that idea (probably because they thought I wanted them to do it--not true). I haven't yet removed the intake (they have it glued down and I'll have to chisel it off) but I still think that would not be a bad idea. Sometimes I am inclined to feel that Murphy rides the backs of some of us more than others. I imagine that boring and bushing 16 rockers would not exactly be cheap (if in fact the rings and cylinder walls are not the culprit)....perhaps on the order 0f $700-$1000. I kind of like Casey's idea on extra drain back tubes but wouldn't do it because of originality. I really appreciate all of your comments, and the best thing is that it helps others who read this also. I assume the plugs on the ends of the rocker shafts are a press/interference fit as opposed to a screwed pluged--this from GTtim's response on the possibility of damage occurring during installation. I'm probably not going to tacke this issue til spring as the car is 170 miles away and we don't have a date yet to move to the new quarters. I'll try and respond back to this forum as to what I find at that time but by then you will all probably have forgotten about this issue. Course this whole problem might not be oil going down the valve guides because I've never seen smoke out the exhaust on deceleration....so when spring comes and we are moved I need to do some serious diagnosis. Thanks again.
wagone and Avanti I

Alan
12-16-2005, 06:17 PM
Sorry Gord; Last night I was thinking, soo I went out today and looked through my stuff and found that shaft that I saved as a souviner. The stands are all the same. The shaft itself is machined with 4 spots to hold the shaft with head bolts. On the front on the drivers side and the rear on the pass. side the shaft has a hole 5/16" that gets oil from the head bolt. If you are going to plug anything it has to be the shaft.The guy that assembled my engine just had the ends of the shaft the wrong way. The ends of the shaft have 1/2" cup plugs same as go on Chevy in the main up,down oil line in the block that if you don't put back in you don't have any oil pressure.