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Aussie Hawk
11-05-2006, 04:52 PM
'morning all,

I heard the other day that the 289's, up until the rocker covers were vented in '63, had a problem building up pressure internally and causing the front and rear main crank seals to leak.

Is this true ?
And if so, should I install;
1) Vents to the rockers open to atmophere.
2) Vents piped to the air filter.

The other question I have is; Are there alloy rocker covers available for the 289, and at what price ?

Cheers
Matt
Brisbane, Australia

PS. I posted a message a while ago about the Holley fitted to my '62 Hawk, running rough, and even running when I screwed the Idle jets closed. A few of you kept telling it must be a vaccum leak, I was adament I had checked it out and there were none. We, you were right! I had plugged in the PCV line onto the vaccuum spiggot for the brake booster, (My Hawk doesn't have a booster). I just saw a 3/8" hose and a 3/8" spiggot under the carb and assumed they went together. Doh ! Now I'm no novice at working on cars, so after I beat myself in the head with an 1" spanner for being a clutz, fitted the PCV into the air filter housing and blanked off the booster spiggot. I've yet to fire her up, some other being done at poresent, but I expect she will run a llot sweeter.
Thanks to all who tried to show me the light. :-)

StudeRich
11-05-2006, 05:04 PM
Matt, welcome from "over the pond"; you can open that 1st duplicate post of this one and click on the trashcan to delete it.

If you have minimal or no "blowby" past the rings none of that should be necessary. You do however need to connect your PCV valve from the Carb to the lifter cover (flow arrow "TO" carb) NOT to the air cleaner!

I find "most" people who complain of seals "blowing" have excessive blowby or incorrect PCV valve, connected wrong, or wrong oil cap (needs limited breather cap to allow some air INTO engine).

Oh, sorry I forgot the Finned Aluminum Valve Covers, those are available from most of us vendors at http://studebakervendors.com they're about $225.00 a pair without breather tubes or $250.00 with.
Good luck with your engine start-up, Rich.


StudeRich
Studebakers Northwest
Ferndale, WA

Mike Van Veghten
11-06-2006, 12:10 AM
Studerich...

Not nessesarilly a correct statement about the "blowby" situation.

While by using the word blowby only...your statement is "bacially" correct...but...

There is not many rings on the market that will not let "some" combustion pressure past the rings. I'd bet that "most" (maybe not all!) Stude engines on the road today have at least 8% to 10% (or more!) leakage. And that's on a decient running engine. A reasonably good broken in "new" engine, one can expect in the 3% to 5% range. Using Total Seal or Childs and Alberts gapless rings...you can expect 0% to 2% leakage.

But I digress back to "pressure" that Matt asked about.
The "leakage" I just mentioned along with the fact that there is 8 pistons running up and down their respective cylinders....there's no windage there? Of course there is.
You should read up on what the Japanese bike engine designers are doing to lessen the effect of the pumping pressures. NASCAR engine builders are also working very hard to lessen the effects...even with the drysump oiling systems...the pumping of air by the [u]under side</u> of the piston is a real problem. The faster the engine turns, the worse the effect is.
I'm trying a few small things on my 299 I'm building to attempt to lessen the effects of air pumping around inside the crankcase. We'll see what happens!?

Mike

StudeRich
11-06-2006, 01:54 AM
Mike; thanks for all the great technical info about 10,000+ RPM engines. All that may be true on on a high revving fully built 299, (I own one) but none of that blows seals or is relevant to a stock, normally driven Stude.

StudeRich
Studebakers Northwest
Ferndale, WA

gordr
11-06-2006, 03:22 AM
quote:Originally posted by Aussie Hawk

'morning all,

I heard the other day that the 289's, up until the rocker covers were vented in '63, had a problem building up pressure internally and causing the front and rear main crank seals to leak.

Is this true ?
And if so, should I install;
1) Vents to the rockers open to atmophere.
2) Vents piped to the air filter.

The other question I have is; Are there alloy rocker covers available for the 289, and at what price ?

Cheers
Matt
Brisbane, Australia

PS. I posted a message a while ago about the Holley fitted to my '62 Hawk, running rough, and even running when I screwed the Idle jets closed. A few of you kept telling it must be a vaccum leak, I was adament I had checked it out and there were none. We, you were right! I had plugged in the PCV line onto the vaccuum spiggot for the brake booster, (My Hawk doesn't have a booster). I just saw a 3/8" hose and a 3/8" spiggot under the carb and assumed they went together. Doh ! Now I'm no novice at working on cars, so after I beat myself in the head with an 1" spanner for being a clutz, fitted the PCV into the air filter housing and blanked off the booster spiggot. I've yet to fire her up, some other being done at poresent, but I expect she will run a llot sweeter.
Thanks to all who tried to show me the light. :-)



Having read the other replies to this thread, I'll go out on a limb and say, the problem is not quite as you describe. Prior to '63, in most non-California cars, the crankcase was vented to the atmosphere via a road draft tube, which originated near the back of the valley cover, and snaked down behind the right side cylinder head and terminated near the lower right of the bellhousing. This tube was about one inch in diameter, and had a "filter" in it composed of metal shavings, not unlike a "ChoreGirl" pot-scrubber pad.

Excess crankase pressure vented to the atmosphere via this tube, and whatever pressure existed in the crankcase was pretty much balanced within the heads and valve chamber.

Move up to '63 and later. No road draft tube; crankcase pressure is vented by a PCV valve (effective diameter about 1/4") connected to manifold vacuum, and by vent caps attached to each valve cover, effective diameter about 1.25", also equipped with filter material similar to that used in the road draft tubes.

In a fresh engine, the suction available at the PCV valve exceeds the amount of blowby gases, and the crankcase is maintained at a slight negative pressure. The vent caps on the valve covers admit fresh air to the engine's innards.

After 60 or 70 thousand miles have gone by, the picture changes. Blowby past the rings exceeds what the PCV valve can pass into the intake manifold. Excess crankcase pressure vents out the breather caps on the valve covers. You now have a flow of air passing UP through the oil drainback holes in the head, and through the passages for the pushrods. Any excess oil from the rocker arms has to fight its way past the rising column of air from the pressurized crankcase, and it tends to lose that fight. With a well-worn engine, oil will tend to pool inside the rocker covers, which don't drain because blowby gases blow strongly enough to force any liquid oil back up against gravity. The valve covers fill with oil, and the pan empties, often to the point that the oil pump sucks wind, and oil pressure falls to zero. This is NOT fiction. I have a '63 Wagonaire with a 289 that had exactly that problem. I installed a less-worn set of rocker arm shafts, and the situation improved considerably. Instead of losing oil pressure after two or three miles at 60 mph, it changed to losing oil pressure after two or three miles at 75 mph.:D

My bottom line: excessive blowby is going to manifest itself as a problem, regardless of which crankcase venting system is used. With the r

Mike Van Veghten
11-06-2006, 12:07 PM
Studerich,

Actually ...yea it is.
Just to a lesser extent.

Mike

Aussie Hawk
11-06-2006, 04:59 PM
Thanks guys,

Your words of wisdom have given me what I was looking for. By the by, the engine in my Hawk was overhauled before I bought her and hasn't done too many miles since.

StudeRich - You say: "You do however need to connect your PCV valve from the Carb to the lifter cover (flow arrow "TO" carb) NOT to the air cleaner"

So, I'm assuming you mean to the base of the carb? Wouldn't this give you the problem I had ? A vacuum leak, with the vacuum from the intake manifold overriding the spring in the PCV.

By the way, do you ship across the pond ?

Cheers
Matt
Brisbane, Australia


PS The PCV hose on my Hawk comes from the rear of the valley.

StudeRich
11-06-2006, 05:22 PM
No Matt, connecting that PCV valve & hose from the lifter cover to the rear base of the Carb. is exactly the California & New York factory original setup, it will not cause any problems if the flow arrow is TO the Carb. because the valve limits the flow and acts as a backfire restrictor to prevent reverse flow.

You can still connect a hose from the air cleaner to valve cover oil cap like the late '64 Canadian Studes imported to Calif. had, for a totally sealed "upper crankcase system" using a sealed cap on the other valve cover if you must. That would come into play at high speed when the air cleaner "draw" exceeds the carb. "draw" from the crankcase. This "upper kit" does not require a second PCV valve however.

To answer your other question YES, we ship all items available at the larger vendors to Australia. We just shipped a large order last week there, and are sending one this week to Perth.

Also, please delete your duplicate post, it's now farther down the list & someome may think it is unanswered & start a whole new string of answers. Thanks

StudeRich
Studebakers Northwest
Ferndale, WA

Aussie Hawk
11-08-2006, 12:23 AM
My apologies if I sound a bit thick !

So, I should leave the PCV hose, from the rear of the valley, connected to the vaccum spigot in the base of the carb?

Connecting it to the air filter is bad - right ?

Cheers
Matt.

Do you supply to individuals in OZ, or just dealers ?

1956 Hawk
11-08-2006, 01:20 AM
Right the PCV goes to the carb. On the R2s an open line went from the breather to the air cleaner so the crankcase could still breath under boost. There isn't going to be enough vacuum at the air cleaner to draw through a PCV valve.
David

StudeRich
11-08-2006, 03:29 AM
Definetely YES on the PCV! Sure, all of us on the vendor web page sell retail, if you need detail info e-mail me, I don't try to discuss and sell things on here, just saying: anything still available we have!
Rich.


quote:Originally posted by Aussie Hawk

My apologies if I sound a bit thick !
So, I should leave the PCV hose, from the rear of the valley, connected to the vaccum spigot in the base of the carb?
Connecting it to the air filter is bad - right ?
Cheers Matt.
Do you supply to individuals in OZ, or just dealers ?

StudeRich
Studebakers Northwest
Ferndale, WA

John Kirchhoff
11-08-2006, 04:02 PM
gordr reinforced with apparent bad results as to what I mentioned a while back concering oil pooling in the valve covers. The only thing he failed to mention is that on pre- 62?-63 engines the hole in the rocker arm shaft that admits oil is much larger than on the later engines. This hole can be brazed shut (not real easy) and drilled out to the later dimensions (3/16"?) which reduces the amount of oil leaking out past worn rocker arms. I did that to my '51 with no ill effects.

As to blow by blowing out seals, I think it would have to be an extreme case like a holed piston. I had a 5 ring Perkins diesel piston burned down to the 4th ring and it chuffed out oil fumes like a locomotive but never pushed any oil past the main seals. I guess if the seal is shot and ready to go it wouldn't take much to finish it off but I really have my doubts.