Carried over from the Valve cover baffle design thread. Dave brought up something I thought may be interesting.







That's certainly not dumb. I don't think airflow through the engine has been discussed in detail. It may not be an area that needs improvement. Slightly more modern engines, such as the 305 in my Firebird, don't appear to have any kind of baffling to direct air flow in any particular way. I'm interested in hearing about it if there is anything important to know.



One thing, if your observations indicate that it's blowing up through the timing cover and into the valley, it must be drawing air from somewhere. The only source I can think of is through the distributor hole. I will guess that the hot crankcase gasses rise to the top of the engine where they can be drawn out and the cooler air will make its way to the crankcase. I guess that would be convection.



There have been at least 3 different arrangements for crankcase evacuation. It will be interesting, if not pointless, to know how they actually compare. My shop manual has a diagram showing how it should flow for the trucks original setup. I'll dig that out.


Lawrenceville, GA

Charlie, thanks for starting a new thread.  I'm honored you picked my dumb idea and ran with it.
Just looking at my timing chain tells volumes:

I know this engine is a mess and worn-out, but look at the witness marks left behind in the next picture.

The bottom end is completely open to the timing set.  That black scale isn't soft sludge, it's baked-on oil smoke.  THAT was the only means by which this chain set got any oil, so we have TWO problems.  I see the middle of the eccentric, which never gets oil, has heavy remnents of blow-by.  It had to rise from the oil pan and migrate up, through the two holes behind the cam sprocket (and into the valley).

So, blow-by is the only air circulating around the bottom (because it is produced there) and it only has one way to go.  I see, the detergent in the oil, splashing on the bottom parts, did its job.  Parts that didn't get any oil never got cleaned.

Royal Oak, Michigan (Four miles north of Detroit, and 12 miles NORTH of Windsor, Canada).  That's right, we're north of Canada.

Ford 292 Y-Block major overhaul by simplyconnected

Do you have any idea about the mileage of that engine? When I tore down mine after 10 or 11K miles, I found no buildup whatsoever and everything had oil on it. I wonder if modern oils might have something to do with it as well. The only thing I had changed in the timing chain area is the modification to the cam retaining plate mentioned in the Eickman book. I don't think that would have any effect on oiling the chain, eccentric, and etc.


Lawrenceville, GA

Charlie, I know nothing about this engine except it came from Massachusetts.  I didn't even want it.  My recent purchase, a '59 Galaxie, has a three speed stick.  My wife likes automatics.  Within two weeks after buying my car locally, I found a guy on eBay who was selling '59 Galaxie parts.

He said he was going to restore his, but after driving it onto the rack, and putting it in the air, he noticed extensive frame rot and decided to part-out the car and recoup his money.  I asked him for the tranny, linkage, brake pedal support, steering column, and drive shaft.  He said the engine and tranny were together but he gave me a real good price for the whole bang.

You can see the engine is on a tire, and the whole thing is on a pallet.  That's how it came off the truck, and this is how I laid eyes on it for the first time.  I don't know the previous owner.

Turns out, the heads are 113's, the crank and cam look beautiful with NO wear, but the cylinders were worn, rings shot, rocker shafts shot, and three spark plugs had 'extenders' on them to save from oil-fouling.  My machine shop magnafluxed the block, took .060" off the cyl's, and skinned the decks and heads for straightness.  If you go to my site, click on the 'Engine Section' to see what I've done so far.

My intention is to have the engine and transmission totally rebuilt, assembled, and ready to drop in my Galaxie right after Woodward Dream Cruise in August.  I also have power disk brakes and a rack & pinion setup to install at the same time.  This weekend, I'm rebuilding the three-speed Cruise-o-matic.

I have never worked on an engine as dirty as this 292.  But one good thing, the history of this engine tells a story.  All I have to do is read it correctly.  I can't do that with a clean engine.

- Dave

Royal Oak, Michigan (Four miles north of Detroit, and 12 miles NORTH of Windsor, Canada).  That's right, we're north of Canada.

Ford 292 Y-Block major overhaul by simplyconnected

Dave- I'm a neighbor to the north of you (Freeland, MI) I know a fella in Howell who has quite a hoard of Y-block motors and parts, (I recently bought all the valve stem splash shields I was missing for $1.00 ea) He's very knowledgeable , to boot- If you'd like, I could scare up his Tx# for you. Just PM me and let me know... /Duck

BOO- YA!!!

The two vent holes in the timing cover area and the larger hole at the back and around the distributor gear do help to vent any excess pressure generated by piston ring leakage back to the top of the engine. This pressure is obviously not near as much of an issue in an engine with a good ring seal as opposed to a worn engine where the rings are permitting some of the combustion pressures back into the crankcase and creating ‘blowby’. This generated pressure is also hotter than normal thus raising internal crankcase temperatures and in turn promotes the baking of oil residues to internal surfaces. The additional air being generated in the crankcase as a result of ring seal and/or the churning of air in general by the up and down movement of the pistons becomes evident when running an engine on the dyno with a lexan (clear) valley cover in place.

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Simple design theory says to keep air flow restricted to the top of the engine where engine heat will bring to the top any unwanted residuals such as moisture. Cool air also needs to be kept from the hotter regions of an engine if for no other reason than minimizing condensation. The ideal situation on a V8 is a positive crankcase ventilation system where fresh air goes in at the front of one valve cover and out the rear of the cover on the opposite side. Making any system more complicated than this simply adds more variables and potentially introducing more undesirable outcomes into any scenario. Giving it just a bit more thought says any added air flow to the lower areas of the engine will create a situation where additional oil particles will be carried to the top and out thru a PCV or crankcase evacuation system instead of the oil remaining at the bottom of the where it ideally needs to stay if in suspension. Keeping any fresh air inputs as far away from the oil sump also extends the life of the oil by minimizing or at least slowing down oxidation that occurs when large surfaces areas of oil is exposed to oxygen.

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On the race engines, I prefer to maintain a slight vacuum on the crankcase in which to minimize the movement of air that’s created by the movement of the pistons. In this environment, the air itself creates an additional drag on the engine.

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Here is a past thread regarding additional holes in the lifter valley.

Drilling additional holes for oiling and/or venting

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As always, just food for thought.

Lorena, Texas (South of Waco)