Engine missing fuel pump plunger

Robin8er · #1 03-11-2018, 11:39 PM

My Lycoming O-360 engine came with a cover plate covering the hole where the fuel pump goes (no fuel pump on engine) I took off the plate to install the pump and it appears that there is no plunger installed. I turned the engine over 1/2 and then 1 full rotation and never saw the plunger, but I do see there the plunger goes.

Is it likely that there is no plunger in my engine? Or would it have to be installed for the engine to work correctly? I just want to make sure I'm not missing something obvious. I bought it used/rebuilt.

cdeerinck · #2 03-11-2018, 11:50 PM

I just custom ordered and received an engine just like this.
I will be making it into a fuel injected engine, with an electric fuel pump.

So the factory (at my request) removed the plunger and put a plate over it.

Sounds like the previous owner did the same here.

If you are putting an engine driven fuel pump on the engine, you will need to install the plunger.

Robin8er · #3 03-12-2018, 12:25 AM

Thanks for the reply. I assume I have to remove the accessory case to install it?

az_gila · #4 03-12-2018, 12:49 AM

Your engine might have simply been made for a high wing plane with no engine driven pump.

Yes... the accessory case will have to come off.

bret · #5 03-12-2018, 06:01 AM

Hey! you're all set up for EFII

cajunwings · #6 03-12-2018, 06:17 AM

I likely have a used spare plunger I could sell. And Yes the accessory case needs to come off to install the plunger.

Don Broussard
RV9 Rebuild in Progress
57 Pacer

Ralph Inkster · #7 03-12-2018, 08:06 AM

depending on engine model, you may also find that the accessory cover may not be machined for a push rod, or the idler gear is plain & without the lobe to push the push rod. Also if it is a narrow deck, while the accessory cover is off, check that the oil pump AD had been complied with.

RV6_flyer · #8 03-12-2018, 10:37 AM

Quote:

Originally Posted by az_gila

Your engine might have simply been made for a high wing plane with no engine driven pump.

Yes... the accessory case will have to come off.

Many of the high wing engines were also missing a gear with an eccentric on it that is needed to move the rod and run the pump. There is gear without the eccentric that is used on those engines.

With the accessory case off, it is easy to change the gear and fuel pump plunger rod.

cdeerinck · #9 03-12-2018, 03:19 PM

I just saw this today. Double check it is what you need.

http://www.vansairforce.com/communit...d.php?t=158588

N941WR · #10 03-12-2018, 05:18 PM

Quote:

Originally Posted by Robin8er

Thanks for the reply. I assume I have to remove the accessory case to install it?

The sump will have to come off before you can remove the accessory case.

Chances are the plunger hole has been reamed since the opening was also milled.