What are these parts?

[Jacob]

Hey everyone, I’m trying to figure out what some of these parts are and for.

 

https://imgur.com/a/EjBAF5O

[Jacob]

I also had a question about the Webber carb and filter. I see were the fuel line goes in and then it looks like something should be connected to the other port next to it. I get a very strong smell of exhaust to the right of the engine compartment. Here are some pictures to help.

https://imgur.com/a/GshA6rc

[thisismatt]

That's the coil and ballast resistor.  The coil generates/supplies the high voltage to create the spark at your spark plugs.

 

The Pennzoil thing is connected to your block ventilation pipe/breather, so it's likely a small air filter.

 

The Weber is fine, that's just how they are set up, probably for daisy chaining another carb.  The smell of exhaust would be coming from your exhaust, not the carb.  You probably have a leak at the manifold or downpipe, or exhaust pipe

[wayno]

Is your valve cover vent plugged off?

 

[datzenmike]

That's the coil as Matt said but it's not the stock coil so who knows how well it's made or how effective it is?

 

The Pennzoil thing means someone has deleted the PCV valve and stuck an oil breather on the block vent. The engine venting into the engine compartment is caused by this set up. If I were you I get that replaced to stock condition. Less smell and your oil and engine will last longer. 

[Jacob]

What does a valve vent cover plug look like and where is it located? 

 

I was thinking of replacing the breather at some point. Less emissions in the engine bay the better. Is there a specific PCV setup I should you?

[datzenmike]

 

 

This is not the exact thing but more or less what you need. The block vent pipe is joined to the PCV valve that is screwed into the intake by a hose as shown...

 

 

 

The PCV valve is totally benign in operation and uses a small amount of intake vacuum to draw fuel and water vapors as well as combustion blow-by that gets past the rings from the the crankcase. Left, these vapors will condense as the engine cools and it pollutes the oil requiring it to be changed more often. Vapors are drawn into the intake and burned with the fuel and air.  Air that is drawn out of the crankcase is replaced with filtered air from the air filter housing to the top of the valve cover inlet. Under certain heavy load and low intake vacuum conditions the blow-by exceeds the PCV's ability and the flow of air reverses out the valve cover vent and to the carburetor inlet where it is sucked in and burned. This way it is a closed system and no vapors or smell escapes.

[Stoffregen Motorsports]

I sometimes build a cheater PCV system, where I plumb the valve cover breather and block breather together with a tee in the middle, then run a hose off that tee to the underside of the air filter assembly. The small amount of vacuum pulled by the carb does help with the smell, but it doesn't pull the same vacuum as a tru PCV system.

 

One note on PCV valves, you can "adjust" the amount of vacuum by opening up the PCV valve and changing the size of the hole in the middle. A small washer (like the kind used for backing up rivets) usually fits and they come with different hole sizes.

 

I also recently saw an adjustable PCV valve in a magazine. They aren't exactly cheap, but they are truly adjustable. http://mewagner.com/?p=444

[mainer311]

17 hours ago, Jacob said:

I also had a question about the Webber carb and filter. I see were the fuel line goes in and then it looks like something should be connected to the other port next to it. I get a very strong smell of exhaust to the right of the engine compartment. Here are some pictures to help.

https://imgur.com/a/GshA6rc

 

The opposite side that angles downwards is a fuel return line. If a fuel return is not being used (most 521's don't use it), and it must be plugged. Please make sure that it is either capped off or plugged. It should be pretty obvious, since fuel would be spurting out of there if it wasn't. 

 

There's nothing wrong with that Pennzoil PC vent filter. I have a large K&N PC vent filter on my truck with a heat shield on the bottom of it. I didn't want all of that oily shit being recirculated back into my carb/valves.

Edited June 6, 2019 by mainer311

[datzenmike]

Yet every engine made since '62 has a PCV valve and it's well documented that there are zero disadvantages to using one. They don't gum up valves on a non direct injection engine because the carburetor or EFI washes them clean with gas... and excellent solvent. Unless fresh air is drawn through the engine, displacing water and gas fumes as well as combustion blow-by, you are missing out completely on these free benefits. Your engine oil stays cleaner last longer and remains freer of water condensation, no oily mess and smell in the engine compartment and cab. 

[Jacob]

3 hours ago, mainer311 said:

 

The opposite side that angles downwards is a fuel return line. If a fuel return is not being used (most 521's don't use it), and it must be plugged. Please make sure that it is either capped off or plugged. It should be pretty obvious, since fuel would be spurting out of there if it wasn't. 

 

There's nothing wrong with that Pennzoil PC vent filter. I have a large K&N PC vent filter on my truck with a heat shield on the bottom of it. I didn't want all of that oily shit being recirculated back into my carb/valves.

 

If I were to buy a replacement of the pc vent, where would I start looking. I’ve been searching with no luck.

[mainer311]

41 minutes ago, datzenmike said:

Your engine oil stays cleaner last longer and remains freer of water condensation, no oily mess and smell in the engine compartment and cab. 

 

There’s zero oily mess, zero smell, and I have zero evidence of condensation of any sort. Not to mention the vacuum lost on that circuit that could be flowing through the carb. 

 

The point of the PCV is for emissions, and let’s face it: a catless Datsun from the 70’s is moving smog.

Edited June 7, 2019 by mainer311

[Charlie69]

8 hours ago, Stoffregen Motorsports said:

I sometimes build a cheater PCV system, where I plumb the valve cover breather and block breather together with a tee in the middle, then run a hose off that tee to the underside of the air filter assembly. The small amount of vacuum pulled by the carb does help with the smell, but it doesn't pull the same vacuum as a tru PCV system.

 

One note on PCV valves, you can "adjust" the amount of vacuum by opening up the PCV valve and changing the size of the hole in the middle. A small washer (like the kind used for backing up rivets) usually fits and they come with different hole sizes.

 

I also recently saw an adjustable PCV valve in a magazine. They aren't exactly cheap, but they are truly adjustable. http://mewagner.com/?p=444

That PCV Valve is $70 less than I pay for most of my Datsuns!  LOL

[wayno]

OK, yes the PCV valve was the first real emissions device to limit hydrocarbons, but before the PCV valve engines were lucky to get a 100,000 miles on them, this is because with no PCV valve oil gets saturated with un-burnt fuel and water vapor, the oil turns to a sludge inside the engine and contributes to a shorter lifespan of an engine compared to an engine with a PCV valve.

For the PCV valve to work properly the engine also needs a crankcase breather, the breather has 2 functions, to let fresh air into the block that the PCV valve is sucking out of the block, and to let air out of the block from blow-by so gaskets don't leak from excessive block pressure that the PCV cannot handle, so the crankcase breather(on the valve cover on an L block) needs to be routed to a filtered source like the air filter housing.

A road vehicle can only benefit from a PCV valve, it helps keep the oil clean and helps the engine last longer.

The PCV valve does nothing to hurt the performance of an engine,  in fact it likely adds a slight amount of burnable fuel( hydrocarbons) into the manifold to mix with the un-burnt fuel already in there.

The pistons on their down stroke pull a certain amount of air into the cylinders, by the time that air gets to the valve that PCV valve has zero effect on that moving air/fuel, fact is that turn it has to make to get onto the cylinder is way more of an issue, the fewer turns that air/fuel mixture/charge has to make the better off you are, down drafts are terrible.

 

[datzenmike]

Back in the day, roads were dark in the center of the lane where the block vent pipe pointed down beside the engine.  I guess it (the PCV) is really an anti pollution device but the benefits to engine and oil life far exceed this. Oil changes can be noticeably extended and the engine stays cleaner inside. Of course you can do as you please but why disconnect something that actively removes engine oil contaminants? Like I said they've been on cars since '62 because they work.

[DanielC]

A hooked up PCV system is a good thing.  It keeps the oil cleaner, longer.  It removed unburnt gasoline from the crankcase, and reduced the dilution of the engine oil.  It has absolutely no effect on engine power output, other than without a PCV system, the engine will wear out sooner.

A good PCV system actually puts the crankcase at a slight vacuum under most operating conditions, and if there is a slight vacuum in the crankcase, less oil will leak out of the engine.  This keeps the engine bay cleaner, and reduces smells in the cab or cabin of the car.

The PCV valve has a variable orifice, so that at idle, under high vacuum, it bleeds little crankcase fumes into the intake manifold, but at idle, there is not a lot of blow by anyway.  as the throttle is opened more, the engine can take in more blow by gasses, and the PCV valve opens more.

[thisismatt]

Trying to convince someone hell-bent on deleting everything that could possibly be construed as an emissions controller device that a PCV system is a good idea is like trying to convince a boarder brother not to put chrome accents on his Civic.

[datzenmike]

I used to scoff that those who want to remove all that 'pollution crap' but gave up. I caution against it, but try to be helpful in that it should at least be done somewhat correctly. Just imagine an engine that runs perfectly fine that has the 'pollution crap' removed and now runs like shit, leaks oil from those little blue filters and stinks of gas in the cab. Mostly it's ignorance of what the pollution controls actually do. You always fear what you don't know. Datsuns had very rudimentary emissions equipment. Back then the engines simply made emissions and the controls just modified or cleaned the emissions up slightly. Today's 'fly by wire' emissions controls won't allow certain engine operations that produce emissions. 

[mainer311]

8 hours ago, thisismatt said:

Trying to convince someone hell-bent on deleting everything that could possibly be construed as an emissions controller device that a PCV system is a good idea is like trying to convince a boarder brother not to put chrome accents on his Civic.

 

C'mon, I'm not a "boarder" brother. 😞

 

Honestly, the reason I put an air filter on my PCV tube was because the original hose was rotting and falling off. It's a PITA trying to rig up a hose with two different sized ends on it. I think I may have found a NOS one a moment ago. Waiting on an invoice.

[datzenmike]

I found a large hose with a smaller harden hose stuffed in the end to get the two sizes on one L20B I had..