Catch can

[Rusty Dawg]

12 hours ago, datzenmike said:

This is a J13. No block vent just a pipe on the top of the valve cover to the inside of the air filter. The oil droplets have a long path to travel to get up there and lots of time and surfaces to attach to. The top of the valve cover will also have some baffles to keep cast off from the rocker arms out. This is for a good running engine. One with lots of blow-by will push the mist of droplets along much faster and could very well spit them into the carburetor.

 

 

 

 

Yup, it was getting into the carb as well.  Going with the container for now I think and then a catch can if that doesn't work well.  Engine runs strong even though smokes.

[Rusty Dawg]

On 6/23/2021 at 9:27 PM, Charlie69 said:

Before paper air filters there were oil bath air filters.

I have both😀

[Rusty Dawg]

On 6/24/2021 at 9:39 AM, Stoffregen Motorsports said:

I have made a few catch cans like the one pictured below. It has a baffle in it that separates the valve cover inlet from the block return line. I use a filter on the top, but it can also be hooked up to a PCV valve for a proper negative crankcase pressure system.

 

For what it's worth, race cars use a similar setup because in high performance engines, blow-by is just normal.

 

Nicely done.  Too fancy for my clunker.

[datzenmike]

3 minutes ago, Rusty Dawg said:

Yup, it was getting into the carb as well.  Going with the container for now I think and then a catch can if that doesn't work well.  Engine runs strong even though smokes.

 

Even cars with a PCV valve will do this when the blow-by gets excessive. Best you can do is a large container filled with stainless steel scouring pads. This will slow the speed of the blow-by and the large surface area will collect the oil droplets. 

 

Generally excessive blow-by is not that present on good running engines. Are you absolutely sure that the oil is not over filled? Find out exactly how much the J13 takes, put that amount in and read the stick. If over filled the crankshaft will whip it up into a fog of oil droplets.

[Stoffregen Motorsports]

Blow-by caused by stuck rings can be helped by adding a quart of ATF to the engine oil. If the ring lands are dirty, the ATF gets in there and helps clean them up. I've used this trick many times for old, gunky engines, and it does work. There are pitfalls to this though. If the crankcase is super gunky, the ATF will loosen large chunks and can clog the oil strainer.

[Rusty Dawg]

3 hours ago, datzenmike said:

 

Even cars with a PCV valve will do this when the blow-by gets excessive. Best you can do is a large container filled with stainless steel scouring pads. This will slow the speed of the blow-by and the large surface area will collect the oil droplets. 

 

Generally excessive blow-by is not that present on good running engines. Are you absolutely sure that the oil is not over filled? Find out exactly how much the J13 takes, put that amount in and read the stick. If over filled the crankshaft will whip it up into a fog of oil droplets.

I filled based on specifications for the engine and at one point it was overfilled by at least a quart.  Not sure why the specs I read online were wrong, but I did drain it until it was just below the full line on the dipstick.  Still had oil getting into the air filter though.  When they installed the J13 engine which never came in my truck, could they have changed the oil pan to make it workable in my truck and thus the dipstick doesn't read properly?  I wouldn't think so, but I am baffled that it was overfull after putting the recommended amount of oil in the engine.

[Rusty Dawg]

2 hours ago, Stoffregen Motorsports said:

Blow-by caused by stuck rings can be helped by adding a quart of ATF to the engine oil. If the ring lands are dirty, the ATF gets in there and helps clean them up. I've used this trick many times for old, gunky engines, and it does work. There are pitfalls to this though. If the crankcase is super gunky, the ATF will loosen large chunks and can clog the oil strainer.

Learned something new today, thanks!!  That does scare the hell out of me though, because I don't want to have to pull that engine out if it clogs the oil pump strainer.  Not sure what to do.

Edited June 26, 2021 by Rusty Dawg

[datzenmike]

I would imagine 3.8 liters, but find out. Ask someone on here. Put the correct amount in and read the stick. Does it agree with the dipstick or not.

 

 

Already covered this.

 

 

4 hours ago, datzenmike said:

 

 Find out exactly how much the J13 takes, put that amount in and read the stick. If over filled the crankshaft will whip it up into a fog of oil droplets.

 

 

[Rusty Dawg]

17 hours ago, datzenmike said:

I would imagine 3.8 liters, but find out. Ask someone on here. Put the correct amount in and read the stick. Does it agree with the dipstick or not.

 

 

Already covered this.

 

 

 

 

I already know it's 4.4 liters, but that showed over a quart too much.🤷‍♂️

[MikeRL411]

On 6/24/2021 at 12:35 PM, Stoffregen Motorsports said:

Even just that small amount of vacuum from the open end of the carbs is enough to help with oil leaks.

 

So the baffle is like an L series, but open on both ends instead of just the one end?

 

Open on 1 end,  It butts up against the end of the valve cover.  It's tilted so that the condensate drips back to the drain to the crankcase

[datzenmike]

12 hours ago, Rusty Dawg said:

I already know it's 4.4 liters, but that showed over a quart too much.🤷‍♂️

 

Sounds like a lot. Can anyone confirm this? Is this with a filter change? Extreme oil blow-by is classic over fill of the crankcase so we need to nail this down. If it's over filled this is an easy fix.

[Charlie69]

On 6/27/2021 at 6:52 AM, Rusty Dawg said:

I already know it's 4.4 liters, but that showed over a quart too much.🤷‍♂️

 

On 6/27/2021 at 7:13 PM, datzenmike said:

 

Sounds like a lot. Can anyone confirm this? Is this with a filter change? Extreme oil blow-by is classic over fill of the crankcase so we need to nail this down. If it's over filled this is an easy fix.

Taken from one of my 520 Factory srvice manuals.

 

 

[Rusty Dawg]

On 6/27/2021 at 7:13 PM, datzenmike said:

 

Sounds like a lot. Can anyone confirm this? Is this with a filter change? Extreme oil blow-by is classic over fill of the crankcase so we need to nail this down. If it's over filled this is an easy fix.

Yes, it's with an oil filter change which I didn't quite get why the difference in amount with or without a filter change.  The filter drains back into the crankcase once the engine is shut off I assume

 

This is what I found on engine-specs.net:

.

[datzenmike]

 

Well I'm inclined to believe the FSM. The Nissan bible

 

This is easy. Drain your oil. Use a measuring cup and put 3 liters back in and take for a drive.   

[Charlie69]

Just ad filter capacity to oil pan capacity and this is what a filter and oil change will take.

[Rusty Dawg]

Makes perfect sense that it should be 3lr. since I had to remove over a quart of oil.  Once I replace the rear seal on the transmission I will do another oil change and I will be using 3.1 qts of 20w-50 this time.

[Charlie69]

Be sure you use a high zinc oil or an additive.

[datzenmike]

You don't need to change it just drain and only put 3 liters back in.

[Rusty Dawg]

9 hours ago, Charlie69 said:

Be sure you use a high zinc oil or an additive.

I was thinking about using Wolf's Head 20W-50 or just 30W with Lucas TB Zinc-Plus.

[Rusty Dawg]

5 hours ago, datzenmike said:

You don't need to change it just drain and only put 3 liters back in.

Sorry, I wasn't clear.  I just want to change the oil after putting some miles on my rig since changing it for the first time in 20 plus years.  I will just place 3 liters back in.

[datzenmike]

1 hour ago, Rusty Dawg said:

I was thinking about using Wolf's Head 20W-50 or just 30W with Lucas TB Zinc-Plus.

 

Rotella T4 in 15w40 would also work. It's high in ZDDP and you don't have to buy two things and mix them. Also if topping up it can be bought anywhere and no mixing up half a quart.