Pulling dirty air into the engine via Audiovox

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Constant Mesh

Well-known member
FJR Supporter
Joined
Jul 11, 2005
Messages
1,798
Reaction score
61
Location
Tenn
With all the concerns about loss of engine compression one might wonder if the Audiovox CC's vacuum requirements may be pulling enough unfiltered air into the engine to hurt anything?

Hopefully not.

The California model is pulling fuel tank vapors into the engine via the vapor scrubbing canister. Don't know if this canister removes dirt particles from the vapor keeping them out of the engine?

 
First, it's not steadily pulling air through that tap. Once the chamber in the CC is reduced to what vacuum the engine can apply, there is no more airflow until the CC has to apply vacuum to its diaphram to open the throttle, and that amount would be so miniscule compared to actual combustion air intake I can't see it being a problem. That vacuum doesn't come directly from the engine, it comes from the reservoir, which is then refreshed by engine vacuum.

Note that the Audiovox unit does have a built-in vacuum reservoir with a check valve, it's just not big enough to make some folks happy. (Mostly because the FJR runs so little vacuum compared to most cars, for which the unit was designed.)

Be assured that the vacuum tap does not have a steady flow of unmetered air into the engine.

 
Last edited by a moderator:
ConstantMesh, I have to wonder what ever prompted you to think about this?

I mean, a man of your intellect, so far beyond us average stiffs..

So many more appropriate things for a man of you stature to cure: economic crisis, Gaza, Iran nuclear, and whether Odot really rides a Harley... all sorts of other stuff..

...and you sit in the garage thinking about unfiltered air intrusion into FJR cylinders?

WOW!

Jes' Kidding..

:rolleyes:

 
The California model is pulling fuel tank vapors into the engine via the vapor scrubbing canister. Don't know if this canister removes dirt particles from the vapor keeping them out of the engine?
Absolutely it does! It's a charcoal canister!

On a CA. model it probably has an Expiry Date.

 
When the AVCC is off there is no vacuum flowing. When the AVCC is set to regulate speed only tiny amounts of vacuum are being leaked into the vacuum port(s) on the throttlebodies. Since I'm using a fuel filter as my vacuum reservoir I don't have to worry about dirt.

These are pictures that I took of rfulcher's AVCC:

VacuumCup.jpg


Solenoids.jpg


PCBBack.jpg


PCBTop.jpg


CPU.jpg


 
Last edited by a moderator:
With all the concerns about loss of engine compression one might wonder if the Audiovox CC's vacuum requirements may be pulling enough unfiltered air into the engine to hurt anything?
So to interpret Ionbeam's photo reply, the answer is yes, there will be a small amount of unfiltered air leaked into the intake manifold during certain conditions. The air that goes into the AVCC solenoid's vacuum chamber when the dump or vent solenoids are actuated is unfiltered air. Then when the engine draws vacuum from the solenoid that unfiltered air will migrate into the engine.

That is unless you use a fuel filter as your vacuum reservoir, in which case it will be filter by that. If you are using a home made reservoir (or none) then this tiny amount of air will be unfiltered. But most of the time there will be no air flow as the main solenoid blocks the vacuum line entirely when OFF.

Is it significant?

 
When I started ridng -- motorcycles (even some new ones) didn't have air filters at all -- we loved those bikes....

Was the air cleaner back then? ;)

Also..., Vacuum:

(or more specifically -- loss of vacuum) from 'Click & Clack': "How can you lose something that isn't there and something you never had?" :unsure: :)

 
ConstantMesh, I have to wonder what ever prompted you to think about this?I mean, a man of your intellect, so far beyond us average stiffs..
I was just about to agree with you when I scrolled down and read ionbeam's post.

Holy Crap!

We've got one (Constant Mesh) going stir crazy and wondering how many angels can dance on the head of a pin

and we have another (ionbeam) sacrificing a poor AVCC to the god of scientific method!

"Winter's a long time going." - Bear Claw Chris Lapp

Take care of yourselves. "What a terrible thing to have lost one's mind. Or not to have a mind at all. How true that is." - Dan Quayle

 
So the AVCC I was just given for my birthday is not going to put air in my bike that is going to ruin it? I am not the smartest guy in the world or this forum which we all know is obviously greater than the world, but I just want to know the layman's answer yes or no as far as damaging my bike. :unsure:

 
So the AVCC I was just given for my birthday is not going to put air in my bike that is going to ruin it? I am not the smartest guy in the world or this forum which we all know is obviously greater than the world, but I just want to know the layman's answer yes or no as far as damaging my bike. :unsure:
If you want to be 100% certain, follow Ionbeam's lead and use a fuel filter as the vacuum reservoir (and vacuum filter).

 
So the AVCC I was just given for my birthday is not going to put air in my bike that is going to ruin it? I am not the smartest guy in the world or this forum which we all know is obviously greater than the world, but I just want to know the layman's answer yes or no as far as damaging my bike. :unsure:
If you want to be 100% certain, follow Ionbeam's lead and use a fuel filter as the vacuum reservoir (and vacuum filter).
I used an '85 Goldwing fuel filter for my vacuum reservoir.

In another post, from another time and another place Radman sez:

Use a fuel filter, Wix# 33028, Napa 3028. Airtight, compact, perfect. Use 1 check valve 214-479 Delco to one port, durable, relatively inexpensive, perfect. I have done many installs with this combo.

 
So the AVCC I was just given for my birthday is not going to put air in my bike that is going to ruin it? I am not the smartest guy in the world or this forum which we all know is obviously greater than the world, but I just want to know the layman's answer yes or no as far as damaging my bike. :unsure:
If you want to be 100% certain, follow Ionbeam's lead and use a fuel filter as the vacuum reservoir (and vacuum filter).
I used an '85 Goldwing fuel filter for my vacuum reservoir.

In another post, from another time and another place Radman sez:

Use a fuel filter, Wix# 33028, Napa 3028. Airtight, compact, perfect. Use 1 check valve 214-479 Delco to one port, durable, relatively inexpensive, perfect. I have done many installs with this combo.


all right when it comes in the mail I will look to see whether these filters go on the CC or the bike, please ready yourself for PM's thanks.

 
Oh,for crying out loud. The air the CC relies on for operation, comes from the TB connection-which has already been cleaned as it has passed through the air filter. Except,of course, the air that is within the CC and the vacumn supply hose at initial install. This is,of course, unfiltered and packed with engine destroying particles, and explosion is imminent. Here is Ion after he learned this horrific lesson--

061011horror_title.jpg


It's important that one pulls a vacumn in these components before connecting it to the throttle body port, much like the precharged AC refrigerant lines supplied with a home AC unit. Otherwise, it's goodbye motor, and any competent Yamaha tech will instantly know how it occurred, and a warranty denial will be forthcoming. Once everything is hooked up, the air within the system is contained, all filtered and safe. Next is Ion's back yard once he came to terms with this.

_44255701_final_wreck.jpg


The vent air quantity is so small so as to be of no consequence.

 
Last edited by a moderator:
Oh,for crying out loud. The air the CC relies on for operation, comes from the TB connection-which has already been cleaned as it has passed through the air filter....
Another concise, calm and conservative reply that is correct and complete by ol' rad.

My exploded AVCC pic set is nearly two years old and was originally sent via PM to kaitsdad, then later posted in another AVCC thread.

There is nothing wrong with a belt and suspenders approach to filtering. Heck you never know when the AVCC may blow, frag up and send metal and plastic debris down the vacuum tube ;) JK!

 

Latest posts

Top