AFM Boot?

[moozieman]

8 minutes ago, siteunseen said:

Living in Ohio you might need it.

If it's a '78 you should be good unless a previous owner rerouted them somehow.  My '77 came off the valve cover and crudded up the throttle body.

 

I've seen people take the hose off the valve cover and replace with a small filter. Can I do that and be able to use a closed boot?

[siteunseen]

I ran my valve cover hose to the backside of the throttle blade to keep it cleaner. They get sticky after a while. 

The efi cars are so effected by closed up intakes that I can't see how that would work very well. Remove the oil cap and see how it dies down. The 240s seem to run good without them, I've seen that a lot. I've seen it on 280s too it just doesn't make sense.

[moozieman]

1 hour ago, siteunseen said:

I ran my valve cover hose to the backside of the throttle blade to keep it cleaner. They get sticky after a while. 

The efi cars are so effected by closed up intakes that I can't see how that would work very well. Remove the oil cap and see how it dies down. The 240s seem to run good without them, I've seen that a lot. I've seen it on 280s too it just doesn't make sense.

I guess my question is what exactly I need to do to be able to use that closed afm boot. I’m not understanding something. Haha. ?

[siteunseen]

I'll look at mine tomorrow and see if I can splain better with my laptop.

[Reptoid Overlords]

The way I understand it after refreshing the F54 engine I have in my car(ZX), is that when you go venting to the atmosphere the EFI cars, you create more positive crankcase pressure. This is certainly true if venting the crankcase breather to the atmosphere, but it seems like I saw somewhere that venting the valve cover breather to the atmosphere also creates problems.

Perhaps I'm wrong, but I believe the best possible configuration of the PCV system is the original way, as designed by Nissan. Perhaps the addition of a non vented catch can is an improvement.

[moozieman]

14 hours ago, Reptoid Overlords said:

The way I understand it after refreshing the F54 engine I have in my car(ZX), is that when you go venting to the atmosphere the EFI cars, you create more positive crankcase pressure. This is certainly true if venting the crankcase breather to the atmosphere, but it seems like I saw somewhere that venting the valve cover breather to the atmosphere also creates problems.

Perhaps I'm wrong, but I believe the best possible configuration of the PCV system is the original way, as designed by Nissan. Perhaps the addition of a non vented catch can is an improvement.

Im not too concerned about looks or anything. Essentially what I want to do is get a new afm boot. Just getting a generic non-ported boot will obviously be easier and cheaper than finding a nissan one or modifying something myself. If I can make use of the non-ported boot, I have to figure out what to do with that hose that had originally been connected there. If i'm understanding correctly, that small port on the afm boot is supposed to go to the valve cover opening. Is that correct? If I disconnect and close the port off, that hose has to go somewhere.

[Captain Obvious]

With the way the original system works, you cannot simply remove or cap off those connections. In addition to feeding the AAR's idle-up function, they also are for the PCV system. The AAR idle-up system CAN be deleted if you feel you don't need the idle-up feature when your engine is cold, but deletion of the PCV system is more problematic

There are two hoses involved that complete a "loop" to pass air through the crankcase. One of them connects from the engine block (below the thermostat housing) to the PCV valve. The other one is the hose that connects the top of the valve cover to the intake duct tube. As part of the way the Bosch L-Jet system works is by measuring the air flowing into that system and metering the fuel accordingly. If you start capping off or venting those hoses, it'll play havoc with your fuel mixtures.

You need both of those hoses, or neither. And if you run neither, you need to be willing to accept the issues that come with that.

[siteunseen]

I agree with the others and should have kept my mouth shut.

When I bought my 280 it was my hobby of the moment so I read all I could find. Then rebuilt the motor and deleted a bunch of stuff. My thinking was less is best so I quickly bought a 240.

If you can spend $70 and keep it stock buy a new accordion boot and consider yourself lucky.

[moozieman]

37 minutes ago, siteunseen said:

I agree with the others and should have kept my mouth shut.

When I bought my 280 it was my hobby of the moment so I read all I could find. Then rebuilt the motor and deleted a bunch of stuff. My thinking was less is best so I quickly bought a 240.

If you can spend $70 and keep it stock buy a new accordion boot and consider yourself lucky.

Ok. Might just have to do that. Might also take a look at that ford taurus afm boot. Thanks for everyone's help!