OK guys, I've searched here, I've searched online.. I'm down to askin the parts houses - none of which answered my question today.

I have a 226 straight 6 (H series - "rouge 6").

PO ran it with no thermostat, the oil has been the color of coal all the time.

Oil pressure is the pits, I did the first 1000 miles with 3 oil changes (intentionally doing frequent to try to clean up the engine). Ice cold it starts off at 25 psi, after a mile I am down to 3 psi and it never comes back up.

Every oil change I added some diesel or additive and let it idle for 20 minutes (no load on that thinned out oil) then drained it out.

Since pressure isn't getting better with TLC and painful short oil changes,
I'm down to rebuilding the oil pump. Hoping that either it is way outta spec or something.

I tried egge and kantor (thanks in advance ksmith203 for the post) - called during their saturday hours (today) but both sent me to voicemail saying they were closed. I'll call again on monday.
I tried all the typical like MAC, LMC, Classic Haulers, Rock Auto, etc.

So here's the questions:
1)Assuming no rebuild kit can be found (neither vendor lists the part on their site, so unless it is an unlisted part they have) what the spec is for the spring length and tension so I can get one locally from fastenal, etc?
2) what's the blueprinting specs (gear end clearance, etc)?

[edit] during the 1st oil change I dropped the cleanout and looked around as much as possible. during the 2nd oil change I dropped the whole pan, cleaner, suction tube and cleaned everything (as well as fixing the front seal leak and the (new) cleanout leak (I caused on the 1st oil change). No cruddy bits, no chunkies, no problems observed with bottom end of engine.

 

Is the pressure relief valve integral with the pump like the V8's? If so, and the spring is still in good shape (not obviously broken or collapsed), I'd just shim it 1/16" or so. I would guess tho that that isn't your problem. Check the end plate on the pump, looking for scored grooves. Also put a straightedge across the gears with the plate off, see if there is a noticeable gap. I think the workshop manual has specs for the clearance there.

If the end plate is grooved, sometimes you can flip it over to the better side, if both sides are machined, and the bottom side isn't rusty.

 

Bryan

Your experience with observed OP is very similar to mine. Knowing that this truck hasn't been messed with and that it still sounds great - even when the gauge looks sad - I'm considering this just another factory feature. I'll be curious to understand if you are successful in 'fixing' this issue.

DW

 

I assumed those pressure readings were on a "real" gauge?

 

Reading from my Motor's Auto Repair Manual, circa 1953, page 533, I quote:

On the 1948-51 models, a non adjustable relief valve is located on the left side of the engine behind the oil filter, and is accessible for inspection.

So chances are it is a spring and a relief valve in the form of a ball. General procedure is to install a flat washer or two at one end of the relief spring when trying to increase pressure. It could very well be stuck or gunked up so it remains open.
There is no pump clearance specifications given that I can find. Generally a close look of a worn pump will reveal obvious wear.
It is a shame you did not pull a main and rod cap to check for bearing wear while you had the pan down. It has been my experience in playing with this old junk for many years that the bearings wear enough to cause pressure to drop before the pump goes bad.
I think I saw a complete pump on a site a while back when I was thinking of building my 226. Luck, my friend.

Edit: By all means make certain you have an accurate gauge.

 

Alrightly, looks like I have another item to add to the warmer weather check list: Oil Pressure Relief Valve.

Thanks to Ray and Ross.

DW

 

No listing in the Parts CD for the spring, it's the only one they don't list...

 

Ross and all, Look closely at part #6666. Looks like an adjustment.

 

correcto on the real guage - my dash cluster is an autometer, electric sending units. a year ago when I first had the beast running I was scared at the lack of oil pressure and put a mechanical - both have the same behavior. I took it to a buddy's place with a full shop setup and he too read "next to nothing" for pressure at idle, and 2-3psi at anything above idle. so with three gauges I would say I am confident those are real readings.

I haven't tore anything apart yet, so was trying real hard to get parts and knowledge before going to the shop. Will let you know what I find...

 

Sure does, and if the lock nut came loose....

 

Well now I dunned screwed things up. I pulled that pressure relief and it wasn't anything intricate, fancy, or worn bad - just gummed up on every surface. There's no locknut or adjustment, part 6666 in the diagram is 1 piece (and mine didn't have a hex shoulder mine had a round shoulder, the flat slot is the installation not adjustment). Spring was in good shape nice and stiff with no deformation. It was already under a good bit of tension so I didn't think there was any purpose to shim it (I could tell the plunger is seating before you start threadding it in.

I pulled the end plate off the oil pump - it lost about a 1/2 teaspon of oil (the pump sits entirely above the pan up high and dry).

No scoring, no grooving on the end plate. Placed a flat across the bottom of paddle, eccentric and housing - everything is flat across with no gap.
(talking the bottoms of both 6650's and 6603)


Was thinking I might be able to pull the whole oil pump based on the drawing but with a little gentle prying all I was able to do is get the eccentric 6650 out (the 5 star piece not the paddle 4 star piece).

Cleaned everything up, made a new gasket myself (6615) and put it all back together.

Fired up, zero oil pressure - none, my idiot light even came on.

Checked the obvious things first, did I leave something loose and all of it blew out on the ground, nope. Is the level critically low, nope (low, but in the safe range).

2 things I can think of.
#1 the new gasket I made was about 1/16 thick (thinnest gasket material I have on hand), the old gasket looks like it is paper thick, much thinner. Would the difference in material be enough to cause the pump not to actuate right?

#2 the 1/2 teaspoon I lost, is the pump needing to be packed with vaseline (this pump is sooo different than anything I ever worked on I didn't pack it, especially since it had nothing to mention in it).

I let it run for 10-15 seconds to see if it would prime / build up pressure - no luck. I then give it one good romp on the throttle (hoping higher RPM would give it more suction). I shut her down, added the 1/2 quart spare I keep in the cab (part down the fill tube, part down the oil filter outside, part down the center oil filter tube). And then cranked it for 20 seconds (key off), let the starter rest for 30, cranked for 20, let the starter rest for 30, cranked for 20 - then give up and came to the keyboard.

 

You could try it without any gasket at all. The original gaskets are usually very thin when used, some pumps don't even use one. Basically the gasket thickness is a leakage path around the end of the gears. If 6650 and 6603 are both flush with the body, you don't need a gasket, as long as 6616 fits nice and flat. You really ought to pull the pump out tho to make sure it spins freely that way.

You won't be able to pull the 4-lobed piece out without pulling the entire pump out. The gear holds it together. If the shaft has excessive clearance in the pump body, you could be losing pressure there (not sure where it would go tho).

 

LIke Ross indicated, your home made gasket needs to come out. Try a very small course of gasket cement, I like the copper based stuff, around the edge of the pump where it needs to seal. Go very sparingly as you don't want it in the pump. As you suggest, pack the gears with grease, vaseline would work. You may regain a prime. The pump works on very tight tolerances and needs the lubricant to seal. Wish you luck my friend.

 

1/16" is way to thick for that gasket . It is a shim , not there to seal against leaks . Check for gear end clearance as Ross suggested . If you can't get parts to improve pressure I would suggest that you lap the body and end plate with a piece of 1/4"glass and 400 grit wet/dry sand paper to improve clearance and fit .

 

Thought I would tell ya what more I have so far....

I pulled the gasket entirely and primed the pump with vaseline. She knocked and screamed and holy crap loud for the first 4 seconds and then she drew up pressure and went right back to purring like always. All this time screwin around with it I think I actually got the oil drained down and let me promise anyone who worries about running with no oil in these old girls you will KNOW if you get a hole in the oil pan, etc. There is no mistaking it, these are not like an alu engine. You could have the radio cranked and you will still know I promise.


I googled some more and came up with this article:
Flathead Basics

Unless someone can attest to anything different the spec (for the v8) is:
"The ‘50 and newer relief spring specifications call for the tension to be between 78 and 87 oz. when compressed to 1.380”"

I set a 2/3 full gallon jug on the spring and it compresses to 1.38 ish give or take... (not the right way to measure tension I know, but it's what I had on hand to test with)
Based on his suggestion I tried stretching the spring a bit.
I measured my spring first - 2.50 inches uncompressed. I then stretched it a full 1/4 of an inch to be 2.75 inch uncompressed. Reinstalled and took a drive. Started out the same 20 psi cold, but then at warm I had the faintest glimmer off the peg - probably 5psi.

2nd run I was back to the same ole - an unreadable gauge.

I know I am just being a bit picky, but it hurts my head to drive a vehicle with a gauge sitting on bad numbers... makes my skin crawl.

The install cavity is probably only 1.75 inch deep, so the spring is always under considerable compression. Stretching it only seemed to make it harder to install.

Considering how loud they are without oil I am going to file this away as learned enough quit playing with it.


Sorry to take so long to update, But I wanted to get 3 or 4 drives in and I been sick, so haven't been driving the girl.