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Cold oil filter, Crusader 270

TerryGerm

Member
Cold oil filter, crusader 270
recent oil pump replacement in engine. Noticed oil filter remained cold after engine is very warmed, hot. Have (1982) twin crusader 270's the other engine runs hot oil filter. I did notice the oil hoses were crossed on the cold filter. I switched the hoses and the filter warmed up, next day ran engine and filter remained cold again.
I removed remote filter system from engine. The engine adapter plate, hoses, oil filter adapter and filter. Filters are napa gold 1191. In any of the remote filter setup there are no check valves or obstructions, there is free flow (air) between all parts. On the engine cast block I see no check valves, just oil ports to and from engine.
Am I wrong to assume the oil flow is from oil pump to the block, to the outer section of the engine adapter plate, down the hose to the outer side of the oil filter adapter to the outer shell of oil filter, out the center of the oil filter up the hose to the center of the engine adapter and onto the engine oil passages.
I have 70 psi oil on startup, 50 psi hot running, 1000 rpm. Why do I have oil pressure to the engine and no or very low flow through the filter?
Is there a built in oil by pass in this system anywhere?remote oil filter.jpg


Thanks for any enlightenment.
 
do the oil hoses get warm when the engine comes up to temperature?

Your description of the oil flow sounds accurate.

I would say its very possible one of the bypass valves have stuck open.

how many hours did you have on the engine???
 
The hoses do not warm up at engine temperature, appears to be no flow in them. this engine has about 900 hours on it but has been a good runner. The oil pump was changed out about a month ago but the boat has not been run since that change out. I have taken the remote oil filter system apart. There spears to be no obstructions anywhere and no check valves or bypass valves anywhere up to the block attachment. Do you know of any bypass systems within the engine, at the pump maybe. I do not know the internal flow.
thanks for your help
 
I have Crusader 270s also, but I don't have the remote filter. The photo below shows where the filter attaches to the threaded nipple in the center. (The photo is looking from the bottom of the engine up at block). That nipple is part of the cast aluminum by-pass valve assembly that's held in place by the two bolts shown. The by-pass valve in my case is a fiber disk (at 10 o'clock) that's held closed by a spring that we can't see.

P1020246 small.jpg

Does your remote filter assembly use the by-pass valve and its nipple?
 
Good point DJR!

That by-pass valve is there in the event of the filter media becoming saturated with contaminants.
In other words, it allows for continued (un-filtered) oil flow to the engine if/when the filter media was to become restricted.

** If the by-pass valve spring is broken or weak, oil may flow directly to the engine without having gone through the filter media.
If that is the case, it may explain why the cartridge feels cool to the touch.


In Terry's case (with the remote oil filter system), the Crusader adapter (that is mounted to the cylinder block) may not incorporate a by-pass valve.
His by-pass valve may be in the remote filter base.

Also, the hose routing to the remote filter base is directional.
In other words, the remote oil filter supply hose must be connected to the filter base port that directs the oil to the outside of the filter media.
The return oil hose must be connected to the port that returns the oil from within the filter media.
See ** above again!


Another possibility may be one of the factory machining ports.
I am not 100% certain on this, but I believe that one passage is plugged off after machining.
If so, and if not plugged off, oil may flow to the oil galleys without having gone through the filter media, of which again may explain the cool-to-the-touch filter cartridge.

(see image below)

SBC oiling system.jpg


 
IMG_2341.jpgIMG_2344.jpg
Thanks everyone for your input. In either case I can discover no bypass valve in the remote filter mount or the engine mounted adapter, there are no restrictions between these two parts. This engine has run for years and anytime I have changed oil filters I have usually run the engine before and it has always been warm. The oil pump has been changed out in the past month and I am just getting the boat ready to run again when I noticed the cold filter also the oil lines to the filter are cold. I have very good oil pressure 75 on startup. I can not see where anything would have changed to cause oil not to reach the filter.

I find the internal cross bore in Rick's image interesting or the idea of it not being plugged off. I would assume oil flow is directly to the filter assembly from the pump into the base of the adapter plate for the remote filter. Then any diversion of oil to the filter would have to accrue at the adapter plate.
 
and the other question is does the adaptor, going to the block, use two bolts or just one, in the center?
 
....................

View attachment 22598View attachment 22599

In either case I can discover no bypass valve in the remote filter mount or the engine mounted adapter, there are no restrictions between these two parts. This engine has run for years and anytime I have changed oil filters I have usually run the engine before and it has always been warm.


The oil pump has been changed out in the past month and I am just getting the boat ready to run again when I noticed the cold filter also the oil lines to the filter are cold.
I have very good oil pressure 75 on startup. I can not see where anything would have changed to cause oil not to reach the filter.
Since you have good oil pressure, that would indicate that the oil pump is pushing oil through the system.
However, since the filter is cool to the touch, that would appear to indicate that not all oil is not going through it.
The question now becomes.... where is the oil going, and how does it reach the areas where the pressure reading is taken if it's not entering/exiting the filter?


I find the internal cross bore in Rick's image interesting or the idea of it not being plugged off.
Again, I'm not 100% certain re; how this would be blocked off.

An example of this would be the cam follower (lifters) oil galleys.
If you notice, the galleys are drilled completely through the cylinder block from front to rear.
Then either welch plugs or threaded plugs are installed at all 6 areas.



I would assume oil flow is directly to the filter assembly from the pump into the base of the adapter plate for the remote filter. Then any diversion of oil to the filter would have to accrue at the adapter plate.
I'm not quite following you on that one!


Here another diagram that may help explain the plugs that are used to block off machining bores.

Note the block off plug shown as
A.
It is very unlikely that this plug has become dislodged, and if it did, where would/could it possibly go?
At the same time, I'm just uncertain as to what else there is that would explain the issue!

SBC oiling system 2 .jpg
 
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Some oil filters have a bypass valve to allow flow when the filter is plugged. This valve also functions as side effect as a one way check valve. Soooo.... oil flow thru these filters is one way.
 
Manomark, the top photo is the adapter plate (CRU 97667) which attaches to the block with two bolts on the outer edge, 10oclock in photo. Oil supply line to the filter is at 2oclock, return from filter is in the center of the cup. The center cup appears to mate up to a similar machined surface on the block filter recess without any additional gaskets, seals etc. It looks metal to metal. In the block landing there appears to be no checks, bypass, etc, only a cross drilled oil passage with a plug in the outer hole.IMG_2352.jpg

Rick, If the only oil flow is from the pump, it will enter the filter "dome" cast on the block through a port just above the lip of the adapter plate, flow out to the filter by way of the outer hose to the outer edge of the filter, back from the center of the filter to the center of the adapter plate cup. flow up to the filter dome and out the port to supply the engine with oil. All the engine oil must travel this path if you go on the assumption there is no bypass drilled into the block or drilled and then plugged.

Other wise if all the oil must enter the adapter plate it should pass through the filter system, unless there is something at the top where it mates into the engine that lets the oil bypass, and I see nothing in the dome that is cast in the engine block that appears that way.

I guess my question at this point is, is there a by pass passage really drilled into the internal block?
 
Some oil filters have a bypass valve to allow flow when the filter is plugged. This valve also functions as side effect as a one way check valve. Soooo.... oil flow thru these filters is one way.

Not sure about these Napa Gold 1191's as to bypass or not, but I'll check the flow and recheck the flow.

also, sorry Makomark about the typo
 
I have Crusader 270s also, but I don't have the remote filter. The photo below shows where the filter attaches to the threaded nipple in the center. (The photo is looking from the bottom of the engine up at block). That nipple is part of the cast aluminum by-pass valve assembly that's held in place by the two bolts shown. The by-pass valve in my case is a fiber disk (at 10 o'clock) that's held closed by a spring that we can't see.

View attachment 22595

Does your remote filter assembly use the by-pass valve and its nipple?

DJR,
If you would happen to have a photo with the filter adapter removed, that is where the remote adapter plate goes. I sure would like to see what is under that place, I am too fat to get under my engine to see it.
 
............
Some oil filters have a bypass valve to allow flow when the filter is plugged. This valve also functions as side effect as a one way check valve. Soooo.... oil flow thru these filters is one way.
The only SBC oil filter that I'm aware of (that has a valve in it), is the filter intended for an inverted installation.
Is that the style that you are referring to?



Manomark, the top photo is the adapter plate (CRU 97667) which attaches to the block with two bolts on the outer edge, 10oclock in photo.
That would be this one.
To my knowledge, there is no by-pass valving in it.
I believe that a gasket is required between it and the cylinder block port.



Oil supply line to the filter is at 2oclock, return from filter is in the center of the cup. The center cup appears to mate up to a similar machined surface on the block filter recess without any additional gaskets, seals etc. It looks metal to metal. In the block landing there appears to be no checks, bypass, etc, only a cross drilled oil passage with a plug in the outer hole.
The portion that I'm referring to (in this image) as the "outer surface" requires a gasket.
The proper compressed gasket thickness allows the center surface to make a finely machined metal-to-metal seal against the block portion.

If a previous gasket had been accidentally left in place, and if a second gasket was installed (making it 2 thicknesses), the center inner area will not mate up to the block properly.

If that was to occur, oil will escape from one side into the other side, completely missing the filter media.

View attachment 22606

Rick, If the only oil flow is from the pump, it will enter the filter "dome" cast on the block through a port just above the lip of the adapter plate,
Yes, but only if the plug A is in place.

flow out to the filter by way of the outer hose to the outer edge of the filter, back from the center of the filter to the center of the adapter plate cup. flow up to the filter dome and out the port to supply the engine with oil. All the engine oil must travel this path if you go on the assumption there is no bypass drilled into the block or drilled and then plugged.
To the best of my knowledge, no by-pass valving has ever been drilled into the SBC block.
Plug
A is installed after the factory machining has been completed.
Unless done by a machine shop, it would be considered to be a non-removable part.

Other wise if all the oil must enter the adapter plate it should pass through the filter system, unless there is something at the top where it mates into the engine that lets the oil bypass, and I see nothing in the dome that is cast in the engine block that appears that way.
The plug A is not cast into the block. It is a part that would be pressed into the oil galley after the machining is completed.

I guess my question at this point is, is there a by pass passage really drilled into the internal block?
When the factory machines oil galley ports or passages, they are restricted to machining straight lines only.
In other words, they do not have access to drill bits that will cut a curved bore.
They join these straight line passages in a way that causes the need to plug one end or other other after they join up........ such as
A and B.

Again I wish to thank everyone for their thoughts and consideration you are putting into this to help someone out.
No need to thank us..... we have your credit card number, and boy are we having fun!

Not sure about these Napa Gold 1191's as to bypass or not, but I'll check the flow and recheck the flow.

also, sorry Makomark about the typo
 
Here is the image that did not show up in my last posting.

As said:

The portion that I'm referring to (in this image) as the "outer surface" requires a gasket.
The proper compressed gasket thickness allows the center surface to make a finely machined metal-to-metal seal against the block portion.

If a previous gasket had been accidentally left in place, and if a second gasket was installed (making it 2 gaskets thick), the center inner area will not mate up to the block properly.

If that was to occur, oil will escape from between these two surfaces (one side into the other side), completely missing the filter media.

Crusader Remote Oil Filter Assy 97667.jpg
 
DJR,
If you would happen to have a photo with the filter adapter removed, that is where the remote adapter plate goes. I sure would like to see what is under that place, I am too fat to get under my engine to see it.

Here's the oil filter mount without the bypass valve installed. This is on a 1977 Crusader 270. I included the oil pump mount so that you can see its location in relation to the filter mount.

P1020198 small.jpg
 
Ok guys! first off I started both of my engines at the same time today and ran for .5 hour. Filter temps were at start up Port 50, stbd 50 after 10 min p61, s134 after 20 min p63, s163 after 30 min p69, s175. After shutting down the engines the oil pan temps were p170, s168.

DJR, thanks for the additional photo, after the adapter in your first photo is removed, there are no further bypass valves in the system. So the oil has a clean shot to the engine from this point. In a standard filter instillation there is a bypass valve, with the remote there is no bypass. The oil inlet to the filter is visible at 12 oclock the outlet is through the center. With my remote filter system I cannot see where there would be any restrictions.

Rick the gasket you are speaking of is a 1/8" square o-ring. CRU-20156, the old one was removed and surface checked with inspection mirror installed new one. I feel it is in correctly. I was thinking of what you have said about the two metal to metal surfaces and any gap. From looking at DJR's photos I feel pretty good about there being a good mating surface. As much as I do not want to think about it, I am leaning toward an internal plug failure, which seems very unlikely. My luck has been so bad with this boat I just bought a lottery ticket, my luck has to change.

How do you check plug "A"?
 
I'd think your "internal plug failure" theory is unlikely.....and, from the temp data, it appears oil is getting into the filter, its just not circulating as it should....have you verified the hoses are serviceable, especially in the inside?
 
...................
Ok guys! first off I started both of my engines at the same time today and ran for .5 hour. Filter temps were at start up Port 50, stbd 50 after 10 min p61, s134 after 20 min p63, s163 after 30 min p69, s175. After shutting down the engines the oil pan temps were p170, s168.

DJR, thanks for the additional photo, after the adapter in your first photo is removed, there are no further bypass valves in the system.
So the oil has a clean shot to the engine from this point.
Only after having gone through the filter media!
Under normal conditions, the oil will first enter the filter media, then exit the filter media and then enter the engine's oil galleys!

In a standard filter instillation there is a bypass valve, with the remote there is no bypass. The oil inlet to the filter is visible at 12 oclock the outlet is through the center. With my remote filter system I cannot see where there would be any restrictions.
Nor would I.
Keep in mind that you are not necessarily looking for a restriction (since you do have good oil pressure), you are looking for an oil path that circumvents the filter cartridge (which may explain why the cartridge is cool to the touch).

Rick the gasket you are speaking of is a 1/8" square o-ring.
OK, then I am in error on that one!

CRU-20156, the old one was removed and surface checked with inspection mirror installed new one. I feel it is in correctly.
By chance were different length bolts used, as in too long?

I was thinking of what you have said about the two metal to metal surfaces and any gap. From looking at DJR's photos I feel pretty good about there being a good mating surface. As much as I do not want to think about it, I am leaning toward an internal plug failure, which seems very unlikely. My luck has been so bad with this boat I just bought a lottery ticket, my luck has to change.

How do you check plug "A"?
Well, I guess that you'd need to pull the engine out in order to access that area.

Here is a standard scenario with a by-pass valve system.
(I realize that you do not have this)

SBC oiling system 3 .jpg
 
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I agree with the others about that plug probably not being the cause of the problem. If that was a likely culprit, we would hear of that happening in the thousands of GM vehicles on the road. But if you want to verify it, you could remove the oil pressure gauge sender near the distributor and probe the vertical passage with a piece of brazing rod or wire. Bend the tip so that you can feel for the intersecting oil passage just above the plug.

I would definitely follow up on MakoMark's question regarding the inside of the hoses. An industrial hydraulic shop could easily make new hoses for you.
 
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In the two photos I attached earlier showing the adapter plate and the filter plate these are the ones I removed after I discovered this problem, they have not been off of the engine in the ten years I've owned the boat. I blew through each hose by mouth very easily feeling no resistance. And even if these hoses were 95% plugged and there were no other problem in the oil system all oil to the engine would have to pass through the hose and filter and the filter would get hot. The hoses are now new, but good. Oil pressure is at 50 psi hot at 1000 rpm.

As for the adapter plate it slipped up into its location very easily, no binding, was held in place by hand and the two bolts ran up by finger until meeting the adapter surface. Snugged the bolts alternating between then using 1/2" wrench, the bolts have copper washers for sealing bolt hole openings. Have proper ring seal in place and should be mated properly to block mounting. I think if the top surface was not up all the way the bottom surface would not be up tight and would have an oil leak at the bottom.
 
I think my cheapest next move will be to purchase the internal adapter for the standard filter instillation and mount the filter back on the engine to see how that works. If I can find the right one.
 
Since the other engine is 'working' you could swap the remote filter subassemblies to the troublesome engine and see if it becomes 'normal'....

As far as the remote filter adapters go, the newer ones are made in two flavors - what you have now and ones that are made to be compatible with the combo bypass valve/adapter....
 
I think at the moment I want to confirm I have proper oil flow from the pump and no passage way bypassing within the engine. That should be confirmed by reinstalling the engine mount filter to verify proper oil flow to and from the filter.

I am not sure I've come across the newer combo by pass remote.... I'll keep that in mind when ever I switch it back to a remote filter system. But first I want to confirm all internal flow is correct. Now off to the bilge!
 
On my Crusader 270s with the standard (in 1977) 13/16" threaded nipple, I use either NAPA Gold 1061 or WIX 51061 filters. These don't have the silicone anti-drainback check-valve.

NAPA Gold1060 or Wix 51060 do have the anti-drainback valve.
 
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The filter cartridge with the drain back valve, is typically used in a remote filter application whereby the oil filter is installed in an "inverted" fashion.
I don't know how Terry has his set up!

In this image, I used a remote filter base for an vertically installed filter (the plumbing would the same either way).

Terry, in post #20 you asked how to check to see if the machining port plug had not shifted.
Although it's doubtful that is has shifted, see the notation (in red) that I found while searching for an image.


SBC oiling system 4 .jpg


Here is what puzzles me:

The engine is seeing good oil pressure.
The cool filer would indicate that very little hot oil is reaching it and/or passing through it.
If the plumbing is correct, the filter should be passing oil through it, and should reach temperature.
If the plumbing is not correct, how then is the engine achieving good oil pressure?

Terry, are you absolutely certain that either the base adapter or the remote filter cartridge unit does NOT include a by-pass valve?




.
 
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