gascolator.. Does a IO 320 D1A need 1

ron sterba · #1 08-20-2014, 08:13 PM

Tried several searches,(VAF) guess I don't have key word so here goes. My 9A (IO-320 D1A)I have a Andair boost pump with filter and selector valve. Will I need a gascolator on the firewall and then my fuel line to the mechanical engine pump or just a fuel line from boost pump to firewall direct to mechanical engine pump? My fuel line (per plans) comes out 7" above exhaust pipe. Don't think a gascolator would fit there plus there is a cross member on engine mount that might hit the lower edge of gascolator. In my mind exhaust pipe and gasoline dont mix. Is there a gascolator or something similar, to act as a sump drain? Or do I need drain point firewall forward? Only drain points are on bottom of both fuel tanks.

Would like your feelings on the subject either way. Haven't called Vans yet.. I'm in Oregon, temperature in summer run in the 90s and little humidity but winter time highs 40-50s with more humidity.

Ron in Oregon 9A N421HJ

Neal@F14 · #2 08-20-2014, 08:28 PM

IMHO, an injected engine "needs" a gascolator much less than a carbureted engine does. We did not install a gascolator on my buddy's RV-8 with injected Titan IO-360 and it does just fine without one. It does have an AFP fuel filter which gets disassembled and inspected every annual... so far no trash has ever been found in the filter.

rocketbob · #3 08-20-2014, 08:28 PM

gascolator = asking for vapor lock problems.

Neal@F14 · #4 08-20-2014, 08:35 PM

Quote:

Originally Posted by rocketbob

gascolator = asking for vapor lock problems.

That too, plus putting a gascolator downstream of a high pressure electric boost pump for an injection system is also probably asking for a dangerous fuel leak.

mrobert569 · #5 08-20-2014, 08:46 PM

In short, if you have an inline filter you do not need a gascolator

Mike Robertson
Retired Das Fed

ron sterba · #6 08-21-2014, 12:50 AM

Then is there ever just a plain "push to drain"valve on the firewall forward side? My friends 2006 cessna C-182 turbo has 3 drains "push to drain" firewall forward. now I haven't seen under his cowling but THREE valves""""? So I have to show pressure at my airworthiness inspection or last inspection of fuel flow pressure,would I just disconnect the hose going to the mechanical fuel pump? and read Dynon fuel pressure widget? I think first I would put 5 gallons in each tank and use the electric pump to push out fuel at hose end (that goes to mechanical pump) to check for debris in fuel lines (downstream of Andair pump & filter) then reconnect the hose to the mechanical pump and then measure fuel pressure off the Dynon. Have (red cube fuel flow meter.).

Thanks GUYS! Vapor lock, YIKES!!! Good that I do not nor do I want to install one with the firewall forward being all done.

You learn all the time in this build project,never ending. Just when you think you see light at the end of the tunnel it turns out to be just another flashlight item..

Thanks
Ron in Oregon

Bevan · #7 08-21-2014, 01:44 AM

For builders in Canada, apparently the MDRA are unyeilding on the requirement to have a gascolator. I put mine in the wing roots to:

keep it in a cool area (helps to prevent vapor lock)
keep it upstream of all the pumps and lines as it's also a filter (Andair)
keep it out of the cockpit for ease of sampling/draining with no smell or drips inside.

It will be very easy to sample/drain fuel in the wing root position.

Bevan

MarkW · #8 08-21-2014, 07:45 AM

Ron,
No need for a drain at the firewall. The standard thinking is that the drain is for a location with a sump (low section). Without the Gascolator you do not have that sump at the firewall. I believe the C172S I used to fly had 13 drains.
I have as you mentioned.
Drains in the tanks, fuel lines to the valve, filter, Andair pump, thru firewall bulkhead fitting, hose to mechanical pump, hose to servo then hose to red cube, hose to divider. Fuel injected engines handle water much better than carb'd engines.

N941WR · #9 08-21-2014, 07:57 AM

Talk to Don at Airflow Performance, he will give you all the info you need.

Basically, firewall forward you want the shortest runs possible and try to avoid 90 degree fittings, except where the fuel line comes up between the cylinders and into the fuel distribution spider.

The real purpose of the gascolater is to work as a water trap. This helps keep a carb's float bowl from filling with water. Injected engines are much more tolerant of water. They may stumble a little but they will keep running, depending on how much water is in the fuel.

ron sterba · #10 08-21-2014, 10:40 AM

Well it sounds like negatives for a fuel gascolator leave me thinking that injected systems are hindered by such a device./ Maybe not so for a carbureted system. So I decided NOT to put that gascolator in. The way things are going in technology we may have water injection systems on the engines for better fuel economy and power. Didnt they have something like that on WW II birds?

As always much appreciated the thoughts!
Thanks
Ron in Oregon RV9A
N421HJ one # off the new Honda Jet .
Maybe not as FAST but a whole lot of fun!