Jabiru Mechanical Fuel Pump Gasket Question

[142YX]

Anyone ever replace the fuel pump on a Jabiru?

The pump gets bolted on with a plastic spacer between the pump body and the crank case, with a paper gasket on either side of the plastic spacer.



The fifth step for the appropriate section in the overhaul manual states "New gaskets must be used when re-fitting the pump. All joints must have 1 face coated with Loctite 515 sealant."



Loctite 515 is a liquid gasket material.. in my experience only used when there is not a hard gasket already in use. I don't understand what Jabiru is saying here. Are they recommending that 515 be applied to the crankcase, and the pump flange in addition to the paper gaskets? Or perhaps on both sides of the plastic spacer? Has anyone actually done this? Anyone just use the paper gaskets and have success?

I have new gaskets ready to go.. it just didn't make sense to me to goop these up in addition on one side as the manual states.

[DCASonex]

I have had mine off more than once. Made own paper gaskets from 0.030" thick gasket stock from local auto supply. I have used 515 and 518 sealant VERY sparingly (you do not want that stuff in the pump workings, or plugging the oil return hole) on both sides of all gaskets, no leaks, but cannot say if sealant is required to prevent leaks.

Caution note: The spacer supplied by CAMit looks to be a bit thicker with correspondingly thinner gasket material for same overall thickness. Check thickness of your gasket material when replacing it.

Hope to see many at Crossville.

David A.

[vwglenn]

My 3300 doesn't have a fuel pump on it.

Thing sounds just like a VW pump. One of the tricks with the VW pump is to add or remove spacers to increase or reduce the pressure. Add gasket to reduce pressure and remove to increase. I'd be careful to make sure any home made gaskets are the same thickness as being removed.

I'll be at CSV Saturday if the weather holds out.

[ldmill]

I changed from the Aerocarb back to the Bing on my Jab3300 and reinstalled the fuel pump. I coated both sides of the paper gaskets evenly and installed without trying to shift it around - I didn't want any of it in the inner workings of the pump. I had no previous experience with it and it squeezes out more than I expected. Sealed up nice and tight though.

Lorin Miller
N81YX

[DCASonex]

I changed from the Aerocarb back to the Bing on my Jab3300 and reinstalled the fuel pump. I coated both sides of the paper gaskets evenly and installed without trying to shift it around - I didn't want any of it in the inner workings of the pump. I had no previous experience with it and it squeezes out more than I expected. Sealed up nice and tight though.

Lorin Miller
N81YX

Lorin,
You are right to worry about getting sealant into the pump workings, but if it squeezed out much more than you expected, might be reason to remove and check that none got into the hole that drains oil back into the crankcase. Judgement call based on just how much you saw squeeze out. That hole is near bottom and very close to the gaskets so does not take much excess to get into it. Oil build up inside of the pump can block pumping action. All that is needed is a barely visible smear (if any) of sealant.

David A. Sonex TD, CAMit 3300