Starter & Master Contactor location

I can't find any info on this one. Firewall components.
The plans locate the Starter Contactor sitting 1/4" on top of the Fuel Line Doubler. It's also too close to the fuel line for my comfort level.
Does anyone have best practice advise here? I also have the new motor mount and gear.
Sorry I can't rotate the photo vertical

Different starter contactor but this is how I did it. I'm a -7.

Here's your photo rotated

Just me

I made the doubler with an extra extension to completely lie underneath the mounting bolt for the contactor.
But it appears the fuel line is too high for the inside baffle to fit. Another problem i need to solve. I think i will be oh because the start lead gets a boot, and I plane to wrap the fuel line fitting with tape or shrink tubing to make it double insulated.

Larry,

It took me a bit to realize your pic got rotated.


I made a slight adjustment to the starter contractor position. I went back and forth with Vans support and they were fine with my adjustment. The relay doubler is shown on the forward side just so it can be seen. It is actually positioned on the aft side of the firewall.

First off I checked my dimensions and that I had the starter contactor positioned correctly. In the correct position per the drawing there was an interference with the fuel line doubler. You can see in the pic that I sent to Vans support where the contactor overlayed the doubler. I moved the mounting plate nut up to use the next rivet hole to eliminate the interference. (Click on the pic and it is rotated).

The master relay is in the original position. The pic shows a relay that I bought from B&C but I later replaced it with the Vans unit since that unit had a metal mounting flange. Since the net result of my mod is that the relays are closer together I had to grind the corner off of the flange of the master relay. The connecting busbar is also slightly shorter to adjust for my position adjustment.

This seems to work just fine. I just checked the clearance for the fuel line and there is plenty of room.

I'm in the process of doing the firewall insulation at the moment. The second pic shows the clearance to the fuel line.

Share a bolt

I'm not in my shop but how about moving the contactor up so it shares a bolt with the other? A small doubler on the front side would allow it to sit flat. Plus it would be further from the fuel line.

Edit...Nevermind. won't work.

RV-14 plans

wirejock said:

I'm not in my shop but how about moving the contactor up so it shares a bolt with the other? A small doubler on the front side would allow it to sit flat. Plus it would be further from the fuel line.

Click to expand...

Hi Larry, one tip is to check the RV-14 FWF plans - they look pretty clean, and the way they mounted the contactors is pretty unique, and does not seem to conflict with the fuel lines.

This is how I reinforced the firewall so I could mount the battery and the two solenoids.

The first picture shows the solenoids viewed from the outside. This shows the red lines indicating the structural angle doubler to support the weight of the battery, and the solenoids.

The 2nd picture show the back view from inside the solenoid. The added angle doubler on the right, and it is connected to the horizontal angle from the top end. At least one mounting point of each solenoid is connected to the added angle double or to the existing angle.

RV-7 Starter Contactor

I tried to stay as close to the plans as possible since I am using a stock Van's firewall forward and engine package, for which the standard firewall penetrations are designed.

I did move the starter contactor slightly downward to capture a rivet hole on the fuel line doubler with the contactor mounting bolt, and used a spacer under mounting hole on the other side the same width as the fuel line doubler. There are doublers on the aft side of the firewall for the starter and master contactors, and ANL fuses.

The starter contactor is still close to the fuel line, but this slight relocation increased the distance to my satisfaction.

And thanks to Larry for his blog, which I have found helpful in my RV-7 project.

Larry,

An alternative that I considered was making the fuel line doubler larger so that the starter relay could sit flush or a separate doubler could be used. I already had my fuel line doubler installed so I didn't like that option. BTW, the amount I had to grind away on main relay mounting flange is very minimal to make it work.

Solution

rapid_ascent said:

Larry,

An alternative that I considered was making the fuel line doubler larger so that the starter relay could sit flush or a separate doubler could be used. I already had my fuel line doubler installed so I didn't like that option. BTW, the amount I had to grind away on main relay mounting flange is very minimal to make it work.

Click to expand...

Exactly the solution I'm working. I will post if it plays out.