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-   -   help with Precision Airmotive Silverhawk vertical draft Fuel Injection (https://vansairforce.net/community/showthread.php?t=109175)

Flyyak 01-27-2014 10:38 AM

help with Precision Airmotive Silverhawk vertical draft Fuel Injection
 
I am about to install a Precision Airmotive Silverhawk vertical draft FI on a 0360 Lycoming on an RV7. My project came with MA 4-5 carburetor and I have already prepared the firewall penetrations for that carburetor. I would like to be able to use the penetration points if possible. I have read post about the standard clockwise mixture control (control arm points down) requiring modification to FAB. I cannot find any post relating to the alternate Counter clockwise version ( arm points up). Any help with info on the alternate (up arm) would be appreciated. Actually I would love to hear about either installation. If down arm, how you solved the interference with FAB, and how you like the Silverhawk system, any problems with the Silverhawk. Thanks.

MarkW 01-27-2014 11:21 AM

FlyYak,
I have the SilverHawk with the standard arm down config. I received it with a straight arm but had FAB interfernce. I traded for a bent arm and it works fine. Still a little FAB adjusting but it works fine. Still very close to the cowl. If you prefer the up arm it requires a complete servo re-configuration from Precision.
Precision has a good website with info on the different arms and configurations available.
Been working great.

jthocker 01-27-2014 11:28 AM

Quote:

Originally Posted by Flyyak (Post 847747)
I am about to install a Precision Airmotive Silverhawk vertical draft FI on a 0360 Lycoming on an RV7. My project came with MA 4-5 carburetor and I have already prepared the firewall penetrations for that carburetor. I would like to be able to use the penetration points if possible. I have read post about the standard clockwise mixture control (control arm points down) requiring modification to FAB. I cannot find any post relating to the alternate Counter clockwise version ( arm points up). Any help with info on the alternate (up arm) would be appreciated. Actually I would love to hear about either installation. If down arm, how you solved the interference with FAB, and how you like the Silverhawk system, any problems with the Silverhawk. Thanks.

I recently swapped a carb for an Avstar injection system ( functionally the same as the Siverhawk).
Your firewall penetrations should work fine (although mine is an RV8).
Alternate Mixture control(arm up) will also need an offset arm, otherwise the rod end bearing will contact the full rich stop ahead of the mixture arm, precluding full travel of the arm.
I used a 7/8 inch spacer to align the shorter height fuel servo with the existing cowl scoop. With that spacer I would have been able to use the standard mixture control(arm down), but didn't know it at the time.
Good luck.

Flyyak 01-27-2014 05:02 PM

Thanks. I have read that the fuel servo is shorter than the MA 4-5 carburetor and others have used a spacer. The standard configuration (down arm) is less expensive. If I use the spacer, will I need to request a bent arm or the straight arm. Any chance that you are anyone may have photos. Thanks again.

SMO 01-27-2014 06:58 PM

Picture
 
Not sure if this is what you are looking for. This was in my RV-4. As you can see I thought I needed to modify the FAB, but then found it wasn't necessary. Was a few years ago ago so don't remember the details (picture was taken to show exhaust failure).


Flyyak 01-27-2014 07:59 PM

Thanks for photos

Rupester 01-28-2014 10:24 AM

Aerosport Power IO-320 w/ Silverhawk
 
My IO-320 came from Aerosport with the "up" mixture arm. I was not able to route the mixture cable via the Vans-indicated firewall location, i.e. even the longest Vans mixture cable wouldn't reach. I relocated the FW penetration to the center inset on the firewall ... that worked like a charm.
I find the Silverhawk a joy to fly. Starts easily hot or cold (once you learn the right protocols),and is delightfully precise in terms of adjustments and response. Cold starts fire on the 2nd blade EVERY time.

Flyyak 01-28-2014 03:12 PM

Thanks Terry. What is the right protocol for starting?

Rupester 01-28-2014 05:43 PM

Almost as many start protocols as RVs ...
 
There's a ton of 'em. Do a search on Silverhawk + Starting or Silverhawk + Hot start. You'll find many. Most of us try several and then settle on one each, hot start and cold start, that work for us.


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