I'm trying to understanding the construction of the cam shaft rear oil seal.
This started with oil spraying the rear firewall and my trying to figure out why.

There is a rear part alternately referred to as the cam "plug", "cap", "seal".

I can see a dark ring around a round metal, that I assume to be the, rear end of the cam shaft.

Is this dark ring "the" seal or the bearings or something else?
Is the rear cap just a protective cover or "the" seal?
Are there two oil seals?
Will the cam shaft rear "plug", "cap", "seal" shrink or deteriorate over time causing it to fall out?

What is what at the rear of the cam shaft?

I can not find a comprehensive exploded view.

Thank you
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1988 244 DL; B230F; LH-2.2; Manual 5-speed (M47)

Thank you for everyone's support. After talking over all views with the Volvo parts counter and having access to their schematics. It is concluded there is no ring or third part visible from the rear of the engine.

The schematic provided by Lucid was very similar to what the parts counter was able to pull up. There is no other seal at the rear. The Cap ( "Cover Washer" #1336763 - on the parts schematic ) is the "seal".

The dark ring I was seeing as a part around the end of the cam shaft was, at best guess, the edge of the previous cap. On a closer look I could see an edge where it was broken and not continuous.

I only have an 1" from the back of my engine to the firewall and have big hands. Without making a special tool there was no way for me to scrape out the old cap material. I needed to drive the car and the depth of the pocket was adequate depth for the replacement cap to be set flush.

So I wiped the area clean with a rag and pressed the Cap in place by hand with the flanged edge in the hole as pictured on the schematic. That held it in place while I blocked and wedged and levered the Cap down. I removed the braided ground wire and removed the wire harness from the clamps at the firewall to allow more room. I was a bit disconcerted by the entire engine pushing forward but then that is the point of having flexible motor mounts ... so the engine is cushioned.

I could not get leverage on the bottom edge of the Cap. The final push was done with a 1/4" block and a Cats Paw 10" pry bar. I put the 90 degree corner of the Cats Paw on the firewall and pressed the nail pulling end into the wood block protecting the Cap and pulled up.

Test driving shows the leak is fixed. I will be carrying some quarts of oil for a while as insurance. I do not see how the available aftermarket retaining plate could be put in with my size hands.

Sorry for the frustration involved in communication. I have been jammed before trusting those who think they know what they are doing but leave out some critical element. Once something is understood it is simple ... but that is the work of understanding.

The answers to the Quiz are:
Is the dark ring around the end of the cam shaft "the" seal or the bearings or something else?
... There is No part that fits around the end of the cam shaft. Look more closely to see if it is the edge of the previous Cap.
Is the rear cam "cap" just a protective cover or "the" seal?
... The Cap is "the seal" AND protective cover.
Are there two oil seals?
... No.

--
1988 244 DL; B230F; LH-2.2; Manual 5-speed (M47)

"I can not find a comprehensive exploded view."

Somewhat oddly, Volvo calls it a "Cup Washer" as item #41 in this Graphic from the Volvo Parts Webstore (a Chicago Volvo dealer with good OE prices).
$2.89 for 1336763

Google 1336763 to see FCP's aftermarket "Cam Plug" version.
$2.50 for 1336763

A simply made retainer strap is shown in this Brickboard Tech Gallery picture from years ago:







--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

Thank you for the exploded diagram.

#34 in the front looks like a seal.
I do not see anything comparable in the rear.

Do you know what the dark ring is that is visible around the end of the cam shaft?
--
1988 244 DL; B230F; LH-2.2; Manual 5-speed (M47)

I don't know how to be clearer than by pointing you to item # 41 in that diagram, directing you to the FCP site and picture, and a photo showing a home made retainer for the "plug/washer" that you're concerned with.


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Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

#41 is the much discussed "cap", "seal" ... I get it.

I get the impression the dark ring around the end of the cam shaft I see in the mirror does not exist to anyone else.

I'm off to get #41 at a local dealer. Maybe they have resources that will explain the mystery part.
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1988 244 DL; B230F; LH-2.2; Manual 5-speed (M47)

It sounds to me that what you are seeing might be just burnt oily film on the Cam and not an additional part at all.
There is the 'last' Cam bearing and that is it until this Rubberised Puck. The puck is the seal that keeps oil from escaping out of the Head.
Not sure why DAKAR09 sounds so angry when you are just trying to understand what we are saying and we are trying to understand what you are asking. sheesh


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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html http://cleanflametrap.com/tony/

I'm not "angry". It's a bit frustrating as there are two posts on this by the OP dealing with the same issue.

We have been as straight-forward as possible, with all the information he needs now in both threads. We cannot possibly understand what is being described "in the mirror" without a picture. Even blown-up diagrams of the parts needed for that repair aren't good enough.

There is no "ring" around the back end of the cam. Period. At least there shouldn't be. Despite what you are seeing in your mirror (which we can't see, btw), we have covered the parts that you should have back there.

We are answering your question. Is it possible your cam plug exploded or disintegrated to the point that there's only a ring left?

Or, maybe your cam plug is completely gone, and you're looking at the actual cam bearing itself. Either way, we have no idea what you're actually looking at.

It sounds like your 'Plug is missing and you are seeing the cam shaft.
The plug is not a bearing or anything fancy. It is just a plug to keep oil from coming out the back of the head. That's the only thing back there that would give you oil on the firewall.
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html http://cleanflametrap.com/tony/

This was all covered in your other thread on the same issue. There is plenty of explanation and description of how to replace the part in that thread. It's a very easy fix, and a cheap part to buy. I have several extra ones in my basement from my 240 track build, just incase there was too much pressure in my motor and I lost one during a rally stage. They're that easy to replace.

Push the disc in (rubber/neoprene coated metal)evenly, put cover plate back over it to secure it (2 10mm bolts into the cyliner head).

The same issue was asked by a different person.
So yeah, I explained it to that person with the 700 series and this person with the 200 series. They may not read every thread and they may not know teh 700 and 200 have almost teh same engine.
That's the way Forums work. Different people ask questions, sometimes they are the same type of question and nice people answer them. without attitude

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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html http://cleanflametrap.com/tony/

GUYS !!!

I read my initial inquiry responses.
You are not answering my questions.

Is the dark ring around the end of the cam shaft "the" seal or the bearings or something else?

Is the rear cam "cap" just a protective cover or "the" seal?

Are there two oil seals?

--
1988 244 DL; B230F; LH-2.2; Manual 5-speed (M47)

It's a plug, a flat disc with a rim around it and a thin neoprene coating on that. It's pinched into the hole that would take the distributor on a 700 series car with the same engine. One of Volvo's stupider ideas. They could have made a ridge on either side of the rim to locate it securely, but didn't.
Using silicone just makes it more likely that it will fall out. You need a new one and install it absolutely dry and square in the bore.