AN 4022-1 primer spray nozzles vs Vans fittings

[rjcthree]

Vans primer kit uses a simple AN fitting to dispense primer fuel into the cylinder. The more traditional way is using an AN-4022-1 fitting, which is a spray nozzle fitting to atomize/mist the prime fuel. I have to imagine that's more effective at helping engine start than the standard fitting dribbling fuel into the intake tubes.

I'm considering putting the $14 each down to for the 4022 route, thoughts?

[Mike H]

The AN4022-1 will not atomize or mist fuel due to the low pressure and volume of the primer pump. It will however spray a fine stream of fuel up into the intake port and around the intake valve bowl area. I have not seen the fitting that comes in the Vans kit, but if it is a non-restricted fitting I would think that the fuel distribution in the intake port would be better with the AN4022-1.

[Canadian_JOY]

Here's a follow-up question... I have stainless braided primer lines in hand and noticed they have -3 sized fittings crimped on their ends (hose manufacturer didn't have -2 fittings so I mistakenly accepted -3's).

I believe the AN4022 is a -2 fitting. Please correct me if I'm wrong.

Is there such a thing as a -3 sized primer fitting? If not, I'm open to suggestions that would be less painful than replacing my pre-fabricated lines...

[walkman]

I had the primer nozzles on my -6. They require silver soldering to copper primer line. Mine cracked after 13 years. Rather than silver solder new line I simply flared new line and used the AN fittings. I was unable to determine any difference whatsoever.

[Mike H]

Originally Posted by Canadian_JOY

Here's a follow-up question... I have stainless braided primer lines in hand and noticed they have -3 sized fittings crimped on their ends (hose manufacturer didn't have -2 fittings so I mistakenly accepted -3's).

I believe the AN4022 is a -2 fitting. Please correct me if I'm wrong.

Is there such a thing as a -3 sized primer fitting? If not, I'm open to suggestions that would be less painful than replacing my pre-fabricated lines...

The AN4022 threads into an 1/8"X27tpi NPT hole and has provisions for a 1/8" tube compression fitting.

[TS Flightlines]

The packages I've done have been both ways. -3 AN fittings and -2AN's for those that want AN fittings and not the nozzle and insert style. The -3 stems are .079 after crimping, and if you dont run the solenoid but a second or 2 works well. Others have used a restricted fitting so they can run the solenoid longer.
Using either -2 AN or the AN805-2 NUTS and AN800-2 inserts with braided teflon would require a custom fitting---no problem.
Tom

[lr172]

I am putting in the primer nozzles because they have small, restrictive orifices. The real downside to unrestricted fittings is that the fuel flow is much higher. If you are not careful with the length of time the solenoid is on, you over prime and cause difficult starting or backfiring.

Another benefit is that the primer nozzles will introduce smaller fuel droplets that will do a better job in starting. That said, I have dribbled gas from a jar into a manifold on several occasions (automotive applications) and starting is not an issue.

Larry