Page 56 of 58
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Fri May 31, 2024 11:09 am
by RiverPatrol
I think there is an o ring holding the piece on the inner shaft in place. Remove that and the shaft comes out.
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Tue Jun 04, 2024 10:29 am
by r1lark
r1lark wrote:So, how does the oil filter canister center shaft come apart so the small diameter rubber gasket under the bolt head can be changed out?
IMG_20240531_105555463.jpg
RiverPatrol wrote:I think there is an o ring holding the piece on the inner shaft in place. Remove that and the shaft comes out.
Yes, exactly right River (not that I had any doubt!

), there is a square cross-section seal there. I didn't want to use too much force because I didn't have the parts manual with me the other day when that was posted.
Now for another question. When I originally replaced the oil filter, it was odd because the filter looked as though no oil had gone thru it; but I chocked that up to the fact that the engine had not run in many years. But when I took the 'new' filter back out the other day, it looked the same way -- like no oil was getting into it. (The engine had oil pressure because I hooked up a mechanical gauge on the same oil gallery as the stock sender.) Anyone ever see this??
I pulled off the oil filter base that bolts to the block and brought it home along with the filter canister. Thinking that if there is an oil pressure relief valve in the base (that would open if the filter element gets plugged up), it may be broke/missing/stuck open.
Any advice or insight will be much appreciated!
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Tue Jun 04, 2024 12:44 pm
by Esteban
Paul,
Very strange what you've observed. Maybe it will help you a little if you revisit this post: Oil Filter Adaptation (not for the adapter, but for getting a clear idea of the oil flow)
https://www.60patrol.com/forum/viewtopi ... 61&p=33208
You'll see there a diagram (crude one) of how the oil flows into the filter and out. There's also a relief valve embedded in the base, and the base itself has two different designs over the years. The early Patrols have a different base.
The oil pressure relief in the base works to bypass the flow in case the oil filter is clogged. Years ago I found in the oil base of mine, that the cavity were a ball bearing with a spring on it, has been wearing out little by little. I was cleaning the base outside, and a bit of compressed air blew the ball bearing out of the seat (the seat was almost gone by then)
In any case, is very odd that no oil is present in your filter.
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Wed Jun 05, 2024 9:45 am
by RiverPatrol
Also, be sure that you have the spring in place over the filter.

Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Thu Jun 13, 2024 5:00 pm
by r1lark
Esteban wrote:Paul,
Very strange what you've observed. Maybe it will help you a little if you revisit this post: Oil Filter Adaptation (not for the adapter, but for getting a clear idea of the oil flow)
https://www.60patrol.com/forum/viewtopi ... 61&p=33208
You'll see there a diagram (crude one) of how the oil flows into the filter and out. There's also a relief valve embedded in the base, and the base itself has two different designs over the years. The early Patrols have a different base.
The oil pressure relief in the base works to bypass the flow in case the oil filter is clogged. Years ago I found in the oil base of mine, that the cavity were a ball bearing with a spring on it, has been wearing out little by little. I was cleaning the base outside, and a bit of compressed air blew the ball bearing out of the seat (the seat was almost gone by then)
In any case, is very odd that no oil is present in your filter.
Thank you for your input Esteban. Sorry it has taken so long to respond, but only today I got a chance to look at the filter assembly that I brought home. (Brought the whole assembly home, including the 'base' that bolts to the engine block.)
Mine does not have an oil pressure relief valve. Apparently there were two different styles of filters used on the Patrol. In fact, the picture River posted just above shows two different parts manuals, with the early (pre-'65??) filter assembly on the left, and the later assembly on the right. Forum poster rdarnell posted some pictures of the two styles a while back:

In these pictures, the earlier assembly that does not have a pressure relief valve is in the middle, and the later style is on the right and left.(Note that there are some parts missing on the left and right).
Here is a screen shot from the Old Car Parts Manual that shows the oil pressure relief ball/spring/plug. The plug can be seen on the back side of the filter base (where the gasket goes on). My filter base has no ball, spring, or plug, and no provision for them.
Late Patrol Filter.jpg
Is the later style with the pressure relief valve a 'full flow' type, where all the oil pumped by the oil pump goes thru the filter? That would be the only reason that a pressure relief (EDIT: bypass) valve would be required.
I believe that the earlier style is a partial flow filter, where only a small amount of the oil pump flow passes thru the filter. Note the very small outlet ports on my earlier style:
DSC09538 modified.jpg
DSC09539 Modified.jpg
This doesn't explain why the filters don't have much of any oil in them........although there is no anti-drainback function in these filters (and none in the base), so I guess over time all the oil finally drains back thru the small orificed hole into the oil pan if the Patrol sits for a long period without running. At least I know that there is no oil pressure relief to stick open and cause this.
Sorry if I'm pointing out info that everyone else knows.
If anyone has any info as to whether the Patrol engine was changed to a full flow oil filter configuration when the change in the oil filter assembly was made, please comment.
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Thu Jun 13, 2024 8:58 pm
by Esteban
r1lark wrote:.
Here is a screen shot from the Old Car Parts Manual that shows the oil pressure relief ball/spring/plug. The plug can be seen on the back side of the filter base (where the gasket goes on). My filter base has no ball, spring, or plug, and no provision for them.
Late Patrol Filter.jpg
.
Very interesting observations. Thanks. I’m sure all the members will appreciate them.
In the diagram from the Old Car Parts Manual, you have circled in blue what looks like the end piece of a horn (trumpet). That piece is the one that keeps the oil inside the canister up to opening of the tube towards the upper part, so almost all the oil filter will remain covered in oil once the engine is off. That tube is broken and missing in the right filter assembly in the picture that has 3 of them side by side.
Hope that is clear. I will try to post a drawing tomorrow that will better convey the idea.
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Thu Jun 13, 2024 9:10 pm
by r1lark
Thanks Esteban. I meant to comment on that 'tube', which is why I circled it in blue........but forgot to. If you notice in the picture that River posted just above my post showing the two different part manuals, the early style filter assembly doesn't use that 'tube' or 'trumpet'.
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Sun Jun 23, 2024 7:56 pm
by DonM
Are all "P" motors threaded in the block for the old style Chimney crankcase vent? My current block has a freeze plug in the location the pipe should go, and I do not want to pop it out if there is no chance of attaching the chimney.
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Mon Jun 24, 2024 5:29 am
by Esteban
DonM wrote:Are all "P" motors threaded in the block for the old style Chimney crankcase vent? My current block has a freeze plug in the location the pipe should go, and I do not want to pop it out if there is no chance of attaching the chimney.
Great question. I will venture to say yes. I’m not at home at the moment to check the different parts manuals (regions and years) and see if different numbers were issued for the engine blocks depending the region.
In Ecuador for instance, the chimney style crankcase tube vent was present until 1978, while in the US and Australia were faced off in the mid 60s. I doubt that Nissan was making different castings for just that small change.
Re: The Quick/Small/(Stupid?) Question Thread.
Posted: Sun Jul 14, 2024 11:23 am
by DonM
For posterity sake, the block does have the provision for the chimney bolt behind the plug.