Late 31 engine question

[midgetracer]

I purchased a Model A with a late 31 engine installed. I pulled the engine and delivered it to a friend who rebuilds engines for me. The engine had std pistons and hard valve seats. The babbit was fine, but it needed a .040 bore and a new timing gear as well as valve grinding. The assembled engine ran well, but after a bit it started smoking oil. letting it sit and restarting it ran fine again , but soon started smoking. After examination, we found the valve chamber full of oil, and the area on the front of the chamber which is usually broke out from the factory to oil the timing gear was not broke out. Was this left in place in the later engines? I have never seen an engine before that has this area as cast and not broken out. The side drain back tube was clear. We knocked out the area with a punch and the engine runs great for long test runs. The engine had obviously been run for significant miles before our rebuild. Did Ford sell engines with this area in tact in late production or what are we seeing? Any thoughts?

[alexiskai]

I've never heard of an engine not having a hole there of some kind.

[Marshall V. Daut]

Does it appear that some well-intentioned soul in the past thought this area had been broken out, so he "repaired" it? This punched-out hole invariably looks crudely done, even from the factory. It could easily fool a beginner into thinking the block had been damaged.
I am not aware that late 1931 engines did not punch out this hole. It's needed for drainage and to limit overflow of oil, as you discovered when you removed the valve cover. I wonder if it was a defective block or was put together at the end of a long shift and got the bum's rush from the "worker"? Stranger things have come off the Ford assembly line. An older friend (now deceased) worked as a mechanic and service writer in a Ford dealership in Missouri in the 1950's when FoMoCo was besieged by quality control problems, such as no piston rings being installed at the factory (documented case). A customer had bought a new country squire type of station wagon and complained of it making rattling noises and seemingly the body shifted when hitting bumps and while going over railroad tracks. A dealer inspection revealed that NO body bolts had been installed on the assembly line! The body was only kept in place by gravity, weight and peripheral attachments bolted to it. So, it wouldn't surprise me that one or two Model A engine blocks made it past inspection without that hole being punched out in the front of the valve chamber. If there's a way for a human to screw something up, sooner or later he'll find it.
Marshall

[midgetracer]

it was defiantly not a repair. First one I've ever seen.

[Wick]

Years ago I bought a engine off the barn floor. When I got home I pulled the head and pan to see what I had. The engine had very little carbon, std. Bore. Why would someone pull such a nice engine?
I started cleaning everything up, except when I went to clean out the water jacket it was packed with what looked like concrete. I never got it cleaned out.

[rotorwrench]

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Ford had experienced complaints of valve chamber flooding on more than a few occasions and it does cause oil consumption. In May of 1929, the valve chamber cover was redesigned to lower the oil return pipe location which was intended to control the oil level better. That front wall of the chamber was always broken through to help lube things in the timing chest and to help feed the dipper tray down below. Ford also had a service bulletin to drill a passage at the rear of the valve chamber down to the rear cam journal to give it better lubrication. That oil pump design is unregulated and it puts out some pretty good flow but not with much pressure.

Model B engines actually have pressure mains so the pressure is directed there with a pretty good flow but the valve chamber still gets fed petty well and they have the overflow hole in the front as well.

If it doesn't have a hole there then it should be opened up at the next opportunity.

[Fullraceflathead]

Maybe the guy on the assembly line had to make an emergency bathroom 1 and the guy next to him promised to take over missed 1 of them!!!

[Kurt in NJ]

Is there a small diamond on the block between the timing gear cover and the valve chamber cover —- a later production engine block,they had inserts for ex valves

[Bob Bidonde]

The hole enabling oil flow from the valve chamber to the timing gears is typically ugly. I have seen holes from round, to rectangular and many ragged ones that look like they were made by dynamite blasting. I read somewhere that the block sand casting molds were problematic for this hole.

[Gene F]

Originally Posted by Wick

Years ago I bought a engine off the barn floor. When I got home I pulled the head and pan to see what I had. The engine had very little carbon, std. Bore. Why would someone pull such a nice engine?
I started cleaning everything up, except when I went to clean out the water jacket it was packed with what looked like concrete. I never got it cleaned out.

You could not take it for a hot tank and get that out?

[Gene F]

Originally Posted by rotorwrench

Ford had experienced complaints of valve chamber flooding on more than a few occasions and it does cause oil consumption. In May of 1929, the valve chamber cover was redesigned to lower the oil return pipe location which was intended to control the oil level better. That front wall of the chamber was always broken through to help lube things in the timing chest and to help feed the dipper tray down below. Ford also had a service bulletin to drill a passage at the rear of the valve chamber down to the rear cam journal to give it better lubrication. That oil pump design is unregulated and it puts out some pretty good flow but not with much pressure.

Model B engines actually have pressure mains so the pressure is directed there with a pretty good flow but the valve chamber still gets fed petty well and they have the overflow hole in the front as well.

If it doesn't have a hole there then it should be opened up at the next opportunity.

You don't care for drilling the hole at the back?

[midgetracer]

Originally Posted by Kurt in NJ

Is there a small diamond on the block between the timing gear cover and the valve chamber cover —- a later production engine block,they had inserts for ex valves

yes, it has the diamond and the exhaust valve seats are hard inserts.

[nkaminar]

Sounds like a warranty issue. Bring it back to the Ford dealer.

[rotorwrench]

Originally Posted by Gene F

You don't care for drilling the hole at the back?

A person has to do it when it is a safe bet that there will be no metal contamination problems such as at overhaul. Drilling the rear cam journal hole was a good idea but it should be done when there is no cam in the way and the debris can be removed. Making the hole in the front is kind of the same deal.

Engines manufactured after the bulletin came out should already have the oil port but I would check any block I worked on to see that it has it before putting an engine back together. Cams can get noisy if the journals get a lot of wear. Bearings can be installed but it requires align boring to prep the block for cam bearings.