Josh,
The oil light is not an indication of pressure at any point beyond the "check valve" (the gizmo at the rear of the block, down by the pan mounting flange on the passenger's side). My guess is that the wire from that device to the light is shorting to ground intermittently under certain operating conditions, somewhere along the way. It may be air flow from the fan or such that makes it happen occasionally. The good news is that it's not telling you about a problem except that there's a bare spot on the wire somewhere. A short to ground in this wire simply turns the light on....that's what the so called "check valve" does anyway when there is no oil flow. Note that it may flash weakly (not weekly!) at about 50-60 flashes per minute at hot idle even in a healthy splasher engine, 6 or 8.
Frank

Frank,
Now that I think of it, the light has been briefly flashing at the rate 50 to 60 per min under load when traveling in third gear at 65 mph. Usually at start up the light is on, but sometimes it is off. I'll take a look at the condition of the connecting wire, because that could be the issue. If the wire is fine, and I still get this indication, what is it telling me? Should I be concerned about the flow of oil to the motor at higher revs? Why would there be no flow at the "check valve" under these conditions?
Thanks,
Josh

Josh,
The 50-60 FPM would only occur at idle speed, as that is the frequency of pump pulses at that rpm. If it is doing so at any speed higher than idle, then it's coincidental. I'm still betting on an intermittent short to ground in the wire. If it happens at high rpm, I'd suspect high air flow from the fan is blowing the wire back against something......maybe not, but it's worth a look.
The light should [i]always[/i] come on in KO/EO (key on, engine off) circumstances but go off as soon as the engine is started. Mine goes off at cranking speed.
There [i]is[/i] flow at the check valve under those conditions but that valve has a "leak-off" feature that allows slow return of the plunger to its seat. When the oil is hot, sometimes the plunger is pushed back down onto the contact pin (the grounding contact for the idiot light) before the next pulse of the pump. hence the intermittent flash. The pump pulses are at 1/12th of crankshaft speed so a 600 rpm idle will result in 50 FPM at idle......if conditions are just right. Several factors enter into this occurrence (or non-occurrence): Plunger clearance in its bore; leakage in the chk valve; tension of the plunger return spring, crud; pump clearances (rarely an issue); oil temp/viscosity; idle speed and maybe some others I haven't thought of......yet.
In these engines, pressure only exists in the line segment between the pump and the check valve (other than minimal pressure to overcome frictional losses through the system).
If the light fails to illuminate at KO/EO , look for an "open" in the wire (bum connection, broken wire, etc.) or the plunger may intermittently fail to drop onto the contact pin (broken or missing spring, crud jamming plunger up).
F

Years ago, I had a 49 8 and it had a oil filter. It was installed in the line to the rear of the block. I was advised by Merritt Marks to get rid of it since there would be restricted flow to that section. Made sense to me, so I eliminated it. I would be interested in Franks thoughts on that.
My "newest" eight (49) had a similar to your blinking of the oil light. The end result was a disaster of all the bearings. The suction line to the pump had a blob of RTV in it limiting oil flow. Every thing was fine at 0-45 MPH. but destroyed the engine AT 65 IN ABOUT 5 MILES. Someone used black RTV to seal the oil pan and when they put it up in place, they must have had to move it around until it lined up. That scrapped some RTV into the input line. I keep it as a reminder to only use RTV to glue weather-stripping!

Wow, Dave! Seems like a chapter in the "Never, Ever, Book". One I'll remember...k

My opinion is that the 8 cylinder engine shouldn't be driven faster than 50 miles per hour in 3rd gear, assuming the usual 4.10 axle ratio. Mine was driven faster (years ago, with leaded gas) and required a couple of valve jobs. When I finally replaced the pistons and rings more recently at about 150,000 miles, I found that the bearings were still good, but some rings were broken, and all the top ring lands were very worn. It had gotten to use more than a quart of oil every 100 miles. When I bought the car (in 1962) it had 113,000 miles on it, and did not burn oil.

Overdrive would be a good idea. The engine is then happy at 65 miles per hour.

Any one have input about the oil filter on a installation on a splasher 8 ?

Yes, amazingly, I do have an opinion on the splasher oil filter subject.
There is no downside to installation of a bypass type of filter on the splashers as long as one uses the plumbing arrangement for those engines. Hudson (and others)supplied a kit (I don't think that it was ever a standard item) that runs a parallel circuit with the rear, main oil line, "bleeding off" some of the oil flow and directing it through the filter element and ([i]this is the important part[/i]) re-introducing it into the oil stream just prior to being discharged into the rear dipper tray supply port. None of the oil volume is sacrificed with this flow path, since it all goes into the dipper tray.. Even if the filter element was to become 100% clogged (which most I've removed [i]have been[/i]), all of the pump's output goes to supplying the tray with oil, just as it would if there was no filter at all.
Addition of a bypass filter using a plumbing scheme that dumps the filtered oil directly into the reservoir will reduce the flow to the tray by that volume. Very bad idea. Frankly, I've never seen that done but I'll bet it has.
I use a set-up that filters both pump outputs (front and rear) [i]before[/i] it is discharged to the dipper tray. Not a full flow in the true sense of the term, but I believe it to be the best one can do in a Hudson Splasher.
Note that there can be absolutely [b][i]NO[/i][/b] interconnection between the two circuits!!! The engine shown is a 212 but the system is identical to the eights.
Frank

Thanks frank.
The setup of the old system I mentioned was not Hudson. Someone just placed the Fram cartridge in the line. A costly mistake for sure. I had never seen the correct Hudson setup and now I understand why it has to be done that way or nothing! . In actuality, I think more frequent oil changes would be a fair alternative.

Similar situation was pictured at Doug Wildricks webpage past few months. Splasher six, noisy bearing- opened up pan red RTV had been used with pan gasket. Chunk of RTV blocked oil to a rod bearing, that was now a spray of lead on the block wall. Think they were lucky enough to rebabbit rod as crank OK. RTV plus oil = TROUBLE even in a full pressure oil engine.
Scott K

There were several details about the twin filter set-up I'm using that I didn't mention since I didn't want to write a book.....I've already done that if anyone wants to read it. Some of you already have.
Yes, installation of a bypass type filter in-line would cause some serious problems. It has the potential of causing mechanical issues immediately, such as shearing of the pin that secures the oil pump drive gear or breaking the "wobble" knob off of the pump shaft. The pump would go into near hydro-lock since the entire pump output volume (of the end that has the filter plumbed into it) would be forced through a 1/16" orifice. Not happenin'.
The filters in the photo are of full flow type for Toyota V-6 and many, many other applications. I chose them for their common-ness and relatively small size and that they had far more flow rate capacity than was necessary. An internal filter bypass (not to be confused with "bypass filter") is also a requirement.
The slight pressure generated by the so called "check valve" is the only impetus for flow through the original type set-up, so one can imagine that the flow is minimal at best with that arrangement.
On the subject of frequent oil changes as a solution, I'm of the opinion that the circulation of unfiltered oil in the 1000 miles (or whatever) between changes is not a good thing.
Just Frank's opinion(s).

I am curious to hear other opinions related to Per's recommendation not to drive the 8 more than 50 mph in third gear. The engine seems fine at 60; my engine is very low mileage (21k). My weekend tinkering and test drives yielded the same results - flashing of the oil light at higher revs under load. I don't think it is a short in the wire.

if it was my car i would put a oil presurer gage in it then you can see if it is moveing up and down
the 2nd thing i would do is take the wirer off the sending unit and put a peace of tape over the end and drive it to the speed that lite flickers if it flickers then you know its short some were in the wirer

Josh,

Interesting discussions have taken place about this. See the topic "Road Speed: 1933 to 1948 cars with Duo-Flow Oiling". I explain my opinion there on February 7, 2015. The last posting on this topic was February 23. There are several good viewpoints expressed there. (The topic should have said "to 1951" or "to early 1952" to accommodate the last several years of the 8 cylinder Hudson engine.)

Also, in connection with rear axle ratios, look at the topic "Engine". The last post on this topic is March 9, 2015. The reason for discussing axle ratios is to match one's expected driving speeds with suitable engine speeds. Overdrive was not an option on 1939 and older Hudson products, which leaves changing the rear axle as the only other relatively easy way of getting slower engine speed in third gear.

Per