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6.5 Block Oil passage diagram?

scottm

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the oven, Scottsdale AZ
Does anyone have a link to an oil passage diagram? I want to block off either the cooler passages or the filter passages, and instead run a single cooler/remote filter circuit.
 
I have my cooler ports ,and filter bypass plugged ,and run the filter only. There's a cup plug in the oil filter base that must be removed if you block the cooler ports . There is also another bypass under the cup plug that is for the cooler . I removed my cooler and dual filters ,because it was costing 30 psi .
 
Easy way.

Install a set of fittings in the cooler ports and jumper these with a good high quality hydraulic hose.

Install a spin on remote filter adapter and plumb the adapter to run the oil through the remote filter/cooler


Option 2 would be to replace the filter with the adapter and jumper the ports to allow flow, then use the cooler ports to deliver the oil to your remote setup.

The circuit is as follows.

Oil flows from the pump to the outlet port, from there to the cooler, then back to the block, then into the filter, through the filter and to the engine oil galleries.


Blocking off the cooler will create a restriction in the flow.

There is a bypass valve in the cooler circuit (IN THE BLOCK) as well as in the filter circuit, but these are fail safe items and not really designed for continuous flow.

Use one of the two methods above and you can accomplish what you need with minimal bother.

Myself, I would install a remote filter base adapter in place of the filter and jumper the ports, then use the cooler ports to deliver the oil to your remote cooler/filter

If memory serves, the rear most cooler port on the block is the delivery, but its easy to check the flow before you plumb it up.

Missy
 
She's back! Thanks Missy! I plan to yank all those relief valves and tap/plug the passages as needed. Maybe I can plug one of the cooler ports and one of the filter ports to get a direct shot from the pump to the filter/cooler. I live in az so no need to worry about super cold oil flow. And don't worry, I build offroad race trucks, so the fab work and stainless/Teflon lines will be clean..
 

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So, from an OE perspective, the oil flow goes from the sump, up the pump, to the cooler, then to the filters?
 
Dont plug anything

Just plumb it as I described and the oil will flow fine.

The cooler ports are interconnected with the filter and to go plugging stuff really makes a mess in there

As I mentioned, the back cooler port is the delivery from the pump, then to the cooler, back into the other cooler port (front) which goes to the filter, then to the oil galleries in the block.

Removing any bypass valves and such will just create a mess you dont need.

You can accomplish what you want easily and not need to mess with much

Have fun
 
I have never been satisfied by explanation of how the bypasses actually work. They are tiny little things with light springs that are suppose to provide a bias and they have different piston areas so that once system is pressurized it seals until the cooler or filter plug (have excessive pressure drop). But I bet they bypass at cold start and just maybe big RPM increases?????

The oil pump is a gear pump and the faster it turns the more it pumps and oil pressure is a resistance to flow so the more you try and pump through a restriction the more pressure you get. The oil pump bypasses at something like 80 psi but I kinda doubt it reaches that unless cold and/or reving up while the oil is still cold?????

Mercuiser use to offer a different oil filter bypass valve when going remote mount filter. It actually was the diesel bypass in the gas engine I think.

I would get advice from the guys that run dry sump systems. They I believe plug the filter bypass sometimes.

4 oil cooler bypass valve
5 is going to the cooler
6 oil filter bypass valve
7 is the cup with orifice (I believe provides extra resistance to slowly pump warmer oil through the cooler if it bypasses due to high resistance when cold)
8 is the return

It is my understanding the clean oil is going through the filter knipple to the oil galleries.

Here is the diagram. Keep us posted.
 

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I opened#7 and blocked #6 ,and plugged the cooler ports, the cooler bypass is now nonfunctional .
 
That diagram does help, where did that come from?

From what I understand, one valve lets oil flow bypass the cooler when the oil is super cold and flow resistance is high. The other valve bypasses the filter if the filter becomes plugged up. Old school chevys have a valve that does the same thing built into the filter adapter, while the 6.2/6.5 have them in the block. I read somewhere that the little freezeplug looking thing has a small hole in it to purge air out of the lines that gets in during an oil/filter change.

I put oil in my new chevy filters to reduce the time it runs with no oil pressure on the first startup after a change (On my engines that mount the filter vertically). But one time I got an air lock in the oil pump on a 350 boat engine. Air got into the pump when the oil was drained, but the pump couldn't purge the air bubble through the new filter because I filled it with oil. So the pump gears just spun in the air bubble and the engine had no oil pressure. I loosened the filter until the seal was broken, and I heard a soft fart when the air passed out the filter. Now I leave the filter loose until the new oil is in, which lets air bleed out as the oil rises in the pump.
 
The diagram came from alldatadiy. The same diagram is in the Helm manual.

Interesting on the air bubble entrapment. The cooler does hold a bunch of oil at filter changes but some probably does drain out and might could get an air bubble at the oil pump. I fill my filters before install to about 75-85% full. I dislike the wait for oil pressure on start up at changes. Once I let the oil drain out of the pan for an hour or 3 and it took a little longer to build oil pressure on start up than I like even with mostly full filters. Since then I don't let it drain more than it takes to start dripping slowly.

I tried to measure the bias the oil filter bypass valve provides. I pushed on the spring while the valve was on a postage scale then with force and area of piston calculated it took something like 16 psi to open the valve. BUT once oil is on the other side it can act like a check valve and I am not sure what happens it may seal with differential piston area and not open until the filter plugs up excessively. If this makes sense it provides some non linear bias 16 psi to start then increases with gallery oil pressure? Since oil pressure is fairly low at idle with warm engine the bias to push through the filter could still be fairly low like maybe 26 psi at idle ????? At 2000 rpm it might be 50 psi differential 3000 rpm maybe 100 psi bias to push through the filter???? If the filter plugs up the oil gallery pressure would quickly drop. With no air in gallery and oil is incompressible if the filter plugs the pressure might very quickly drop to less than 10 psi and the bypass valve opens and kind of oscillates ?????

Its a fail safe or some means to ensure very quick/ low oil pressure seen at pump on start up to get oil to the oil galleries??? I have never seen a plugged oil filter. But can imagine significantly different oil pressure restriction depending on how dirty, flow rate, and oil temperature.
 
If the bypass valve does check lock it probably does so quickly as it only takes a few ounces of oil to fill the oil galleries. But if you go adding a "remote" big cooler and filter system with appreciable resistance then I would look into more detail if the bypass valve should be understood exactly.

Kind of sort of related I THINK GM increased the oil cooler line size to increase flow through the cooler or to reduce oil pressure right at the pump ???? Or could it be somehow related to how the bypass pressure valve works ?????
 
I think it's probably just low tech failsafes to keep the engine running for people who never change their oil and filter. I worked in a machine shop in the 80's and we saw engines that had literally never had an oil change. The valve covers fill up with sludge to the underside of the cover. The springs move up and down in a solid block of what looks like cast rubber. You can read whatever the valve covers say cast into the sludge. So for goons like that, the filter bypass keeps their bearings going longer than they deserve!

For any properly maintained hi perf engine, the first thing you do is eliminate the filter bypass. And Phoenix never sees less than 30° mornings in the winter, so I have no problem eliminating the cooler bypass too. If needed, I will put a oil thermostat in the cooler plumbing.
 
Someone help my sad ass! I have tried THREE oil filter bypass valves for my 93 6.5 599block, and nothing seems to fit... the machinist lost the OE... the PN ending 006 w/ blue ring is the one suggested, and the closest fitting but it just doesnt want to sit in there... anyone come across this problem? =( =(
 
No I have not. Sounds like the machinist needs to cough up some parts. Is it the parts that go in the block where the oil filter sits? Maybe a few pics would help us.
 
OK I'm bringing this back up to the top since I'm basically in the same boat. I finally got my 6.2td together and in the truck. Everything is good except the oil cooler bypass. I've looked and bought a few different part number and none are the correct size. I'll be running an oversized plate style cooler so even just blocking the bypass off is fine with me. Just wondering what anyone else has come up with.20180314_194023.jpg
 
Call Ted's for a used one off a blown engine or maybe Lerory Diesel. Any luck with the machine shop? Seriously they need to step up for putting you in this situation of loosing "classic" "collector" or otherwise "rare" parts.

Like The Challenger Space Shuttle you will get away without the bypass till you don't. Likely on a cold day. No flow of cold oil (Oil pump bypass wide open at full pressure but oil not moving through cooler) starves bearings or high pressure pops something. You can see what our taxpayer dollars found with Low-Temperature oil Pumpability... in a 6.2. http://www.thetruckstop.us/forum/th...bility-in-a-6-2-internal-oil-flow-info.41477/
 
Call Ted's for a used one off a blown engine or maybe Lerory Diesel. Any luck with the machine shop? Seriously they need to step up for putting you in this situation of loosing "classic" "collector" or otherwise "rare" parts.

Like The Challenger Space Shuttle you will get away without the bypass till you don't. Likely on a cold day. No flow of cold oil (Oil pump bypass wide open at full pressure but oil not moving through cooler) starves bearings or high pressure pops something. You can see what our taxpayer dollars found with Low-Temperature oil Pumpability... in a 6.2. http://www.thetruckstop.us/forum/th...bility-in-a-6-2-internal-oil-flow-info.41477/

Sadly this block was machined about 5 years ago then I stored it. So no chance of anything out of them.

I didn't even think to try either Teds or Leroy.

Yeah it's better to make sure it's right. 5th time I've had the engine out of this truck in the 18 years I've had it.
 
Still no luck finding the correct one. I did manage to measure the opening in the block. Measured .890 inches. The wrong bypasses all measure .100 smaller.
 
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