From: 29AV8 (Original Message) Sent: 3/16/2007 10:41 AM
What's considered 'acceptable'? Mine is an 8BA block with an early manifold, and I have breather caps on both ends for cross ventilation. It runs well but at a stoplight there is noticable vapor. Without hood sides it will waft up to where you can see it from inside the car, and other motorists think something is burning. I don't get oil smoke out of the tailpipes.

I know older engines do some of this, but what's considered too much? Could changing oils to something like a Delo make it better? Or is it rings?


From: moefuzz Sent: 3/16/2007 3:48 PM

Irregardless of whether you have a pcv systems or not,

.....I'd be tempted put a vacuum gauge on the engine and observe the readings during normal driving.

An engine in good condition should read between 17 - 21 inches at idle with a steady needle

A vacuum gauge will help you figure out what the internals of the engine are like.

As far as blowby goes, the 'after effects' tend to be more noticeable when you pull up to the light as you have noticed.

Driving down the street at 40 mph a person will notice that the vacuum gauge will read a steady 5 or 10 inches as the engine is not working hard to idle the car along at that speed.. Putting your foot into it and accelerating and then maintaining 70 mph will cause the needle to drop to zero inches and beyond into (a) pressure.

When the needle drops to below zero (pressure), The engine starts pushing fumes and residue out thru any/all openings. This would tend to exaggerate the small amount of fumes that would normally be present as you pull up to a stop sign, Some of the fumes may be caused by the excessive residue burning off the hot engine and components just after working/running the engine in a positive or pressurized state.

The optimum engine operating rpm will be at the point were you are able to drive along while maintaining some sort of negative reading. Preferably 3 or 5 inches of vacuum - as a normal engines pcv systems will still have enough air movement to draw fumes/blowby out of the crankcase and direct it into the cylinders/combustion chambers were it is consumed in the charged cylinder.

...As you tend to work the engine harder and the vacuum drops to zero and then starts/creates a pressure, The ability of the pcv system is severely hampered in that the accumulative effects of blowby (fumes) are not drawn into the charged cylinders and accumulate inside the crankcase and engine.

When you pull up to a stop sign, These accumulated fumes are more noticeable as they waft out of the engine.

On a tired engine or one with no pcv system, there is little you can do about excessive blowby/smoke when you pull up to the stop sign....Other than, be aware of your driving habits and use the vacuum gauge as your guide in as to how far you push the gas pedal while cruising along,... Allowing the engine to work with somewhat of a negative reading on the gauge will aide in moving the accumulative fumes thru the pcv system and into the cylinders to be burnt off with the charged air/fuel mixture. Driving/cruising with a heavier foot will cause the engine to become pressurized and the fumes will accumulate in your engine and be far more noticeable at the stop lights.

Excessive blowby is usually a good indicator that your cylinder walls and/or rings are worn.

Glazed cylinder walls will allow increasingly larger amounts of gases to slip out of the pressurized cylinder, past the rings thus creating more blowby. Worn rings will do the same.

A person can take some of the glazing off of the cylinder walls without tearing the engine apart.... ... changing the oil to a non-detergent oil, and running the engine on it for a couple hundred miles, can have the effect of taking some of the glaze off the cylinder walls which aides in creating a better seal with the piston rings etc...

Just my two cents worth...


From: Rumbleseat4 Sent: 3/16/2007 5:36 PM
Very nice presentation and very thorough. Thank you for taking the time to prepare and share it with the rest of the guys.
...rumble seat

From: 4tford. Sent: 3/16/2007 6:23 PM
Yes Rumbleseat, Moefuzz is another one of the fellows you should meet. But be sure to book a FULL day. I don't know where he comes up with all this stuff but he is sure a gold mine. Bill

From: moefuzz Sent: 3/17/2007 1:17 AM
Gee guys, Thanks for the compliments.

It's especially nice hearing it from a couple of the founding members of the Flathead board. And yes, if you're every up this way, It would be a pleasure to absorb some of the good flathead knowledge over a cup of coffee...

From: Butch11443 Sent: 3/17/2007 9:05 AM
Very nice presentation. Thanks for posting it for all of us.

From: Russ/40 Sent: 3/17/2007 12:00 PM
moefuzz, could you elaborate on how using a non-detergent oil for a few hundred miles will break the glaze on cylinder walls?

From: moefuzz Sent: 3/17/2007 12:50 PM

It was an old mechanic friend that first told me about non-detergent or break-in oil years ago. And that's what he called it, Break-in oil. I was having trouble with a 60's 350 powered truck that smoked and his advise was to use a break-in oil to take the glaze off the cylinder walls.

Break in oils contain special additives that aide in seating rings etc., They can also be used on older engines to re-break in the engine (not really but...) or re scuff the cylinder walls.

This is not a be all to end all but it will take some of the glaze off the cylinder walls, more if you leave it in longer.....

hope this helps....

From: Rumbleseat4 Sent: 3/17/2007 3:26 PM
Another old trick for removing the glaze from cylinders and to seat new rings that refuse to seat (such as Chrome rings etc.):

Get the engine warm. Pull the plugs and dump in slighly less than 1/2 teaspoon of Bon-Ami scouring powder into each plug hole. Install plugs and start engine. Let it idle for about a minute and then drive it 35-45 mph for 25 miles without shutting it off. Immediately drain the oil and change it along with the oil filter (if you using one).
This is a very effective way to seat rings and remove glaze and was often used in the old days. Story: Ron, who builds the minature engines, couldn't get the rings to seat on the little Offy you've seen and heard run on this and the Fordbarn site. He was about to pull it down and re-ring it when he was told to try the old Bon-Ami trick. Tried it. Stopped burning oil instantly.
It's worth a try. ....rumble seat

From: ohronnie1 Sent: 3/17/2007 4:02 PM
Bon ami into the engine is a disaster!!!!

There is no known way to get the results you need without a re ring.
The honing paste created inside the engine when you add bon ami gets everywhere inside the engine and it quickly wears itself out and there will be very few areas that the wear does not effect. If you think that this magic cure is going to work just call up the teck line at Hastings Rings and ask them and get it from the the guys that know and hear this horror story every day. The phone call is free.

thats my 2 cents.


From: Russ/40 Sent: 3/17/2007 7:24 PM
moefuzz - thanks for the links. Timely too, as I'm about to drop a new motor in my '49.

From: Ikkyu5149 Sent: 3/17/2007 9:34 PM
Thank you for that vac gauge testing page I haven't seen one that thorough in years.

From: moefuzz Sent: 3/17/2007 10:34 PM
rumble seat,

My Uncle used to use bon ami down the cylinders pretty much as you described, except he would roll the engine over without gas or spark for a good ten minutes or so.
Then rehook the spark and carb and blow the residue out the tail pipe.

I have also heard of people incorrectly adding it to the crank case but that's kinda what ohronnie is pointing towards.?? It would throw bearings out faster than a brand new chubby 6 going up a hill (splash oil system).

....everybodies had different experiances from different view points... All humble opinions are good, with two cents or not


From: moefuzz Sent: 3/17/2007 10:50 PM

I have often wondered why some engines pull like gangbusters from the factory when the next one off the line is a dog and dies an early death, All things considered, the cam/pistons/heads etc are all the same... One variable is the amount of time spent with a non-detergent or break-in oil.

A poorly broken in or poorly seated ring job is like haveing 75,000+ miles already on the clock. -until that engine is set up, it is down on power. I'm sure we've all noticed how strong an engine is at 10,000 miles versus the first few hundred or so miles. That is basically what the John Deere link is implying.....
""""The first 100 hours of operation are critical to the life and performance of an engine. During the first hours of operation, the rings and liners must seat (establish a pattern) for proper performance. If this does not occur, the life of the engine can be adversely affected""""

They aren't jokeing, performance and longevity will suffer, The engine will allow blowby at a serious rate until the rings are set..

Just my opinion and meandering thoughts. Others may not share this opinion..

Rod, I found the vacuum chart several years ago somewhere on the internet. I tend to almost always save interesting pics/diagrams and even whole web pages.. But the amount of pics/diagrams becomes harder to search with so many "important" and "gotta have" pages stored on the hard drive.


From: nort Sent: 3/18/2007 3:12 AM
Man I know about this as I just pulled the eng from my 33,It just completed a 2000 ml run with out a problem,put it away in the shed,started it up a month later and it sounded like it had hammers tied to the crank, pulled the eng out thinking the worst but all was wrong was so much carbon the the pistons hit the head, this eng was rebored about 10000 mls ago but the ring never beded in ,the bores are as smooth as, will fit new rings and deglaze the bores.

From: UrbanCarnut Sent: 3/18/2007 7:11 AM
Just another thought! Think about it--"Modern" oils contain copius quantities of anti-friction additives((that EPA thingy-ya know) that reduces friction(groan);so what "we" need is an anti-friction --friction oil--so put in "old fashioned" straight non-detergent/non anti- friction oil; if you can find it, and give it a try--at least it will still lube the innards.Perhaps Capella oil would do-I think it is refined base engine oil for A/C compressors--?? Sorry; but, I'm also a "do not do" for the soda routine--that stuff is Rough! Dewey

From: pete237 Sent: 3/18/2007 10:22 AM
If I were you I'd get that engine on a cylinder leakage tester. Wet/dry compression testing on an engine with shot rings is useless in my experience. I once wet/dry compression tested an engine with an oil consumption problem and it tested great, only on the cylinder leakage tester it checked out to have around 50% leakage, and upon teardown, just about every oil ring in it was broken. Any decent garage should have one.

Ha, I've seen the Bon Ami trick pulled a couple of times. One I remember was on an 8V 92 Detroit diesel. The end result was a new set of liners and a rebuilt blower. I can't recommend it.
You don't mention whether this engine has had a recent overhaul, been in storage for awhile, or is original, so it's just possible that the rings are stuck. I've fixed a few with stuck rings simply by buying some oil detergent from NAPA and following the directions on the can.
All old road draft tube type engines smell, and that's a fact. Seeing a bit of vapor at a stoplight and smelling it is normal to some extent.

From: OriginalJWL Sent: 3/18/2007 12:02 PM
Have you considered running the tube, the one which emits most of the vapor, into the bottom of the air cleaner base plate so the engine has a chance to burn some of it? There has been examples where this actually improved fuel mileage too.

The concept of adding additional vertical scratches in the cylinder walls and piston rings by putting an abrasive in the cylinders is simply rediculous to consider.

The proper breakin of the rings/walls has a lot more to do with technique than the type of lubricant you use. Many of the engines, which show poor ring sealing, after rebuild, have been run extensively before the car they were installed in was ready to drive. Or maybe on a "test stand". As soon as practical a new engine should be subjected to maximum load, full throttle acceleration cycles. I suggest we visit some of the Ring Manufactures sites, such as Hastings, and read some of their suggestions for breakin.

From: finn34 Sent: 3/18/2007 12:56 PM
I started to wonder about the smoking, but no smoke out of pipes. Does it consume much oil? Does it puff out of the oilfiller when you take away the breather with engine running. I have had an engine take a lot of oil after some hundred miles, even smoke badly out of the pipes, but even then no smoke from breathers (the reason was worn cylinders, the rings were nearly new, so maybe not applicable for you). On idle or after stopping i got some smoke, that was oil that had splashed up on the intake, obviously under the carb, where the heating for the carb is. I think i had an "open in the middle" intake gasket. Maybe that is what you get, or some small leak that drops oil on an exhaust manifold? A tube to the bottom of the aircleaner sounds like a good idea. Maybe you should put a wound wiremesh in the tube as a flame protector.

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