Sump half moons just keep leaking
 

Every engine we have put together this past year has had a half moon seal leak develop after a couple of thousand miles.

Can someone else who has built a few please tell me what seals theyre using, what sealant and their technique. We seriously cannot get it right, the half moons seem to just shrink and create a leak.

Thanks,
Dann

oem
light bead with slight level-out with a finger

Are you torquing bolts to spec and proper pattern? What sealant are you using and how are you applying it? What are you doing to prep the surfaces?

Would you still use a finger to seal a full moon?

for you, the whole fist

:bowrofl:

There is no torque pattern in the FSM. Its annoying.

https://www.miataturbo.net/general-m...oil-pan-38498/

I used neogenesis's instructions. with silicone above and below the seal. Which I believe is what curly has told me to do in the past.

I'll let you know if it leaks :)

Im using that exact procedure with OEM seals.

Toyota black sealant.

They all leak.

..anyone..?

Dann

Oem seals
Three Bond, black RTV

glue the moon to the pan in the evening. Wake up in the a.m. and install pan, again using the RTV .

When I tried to do it all at once, the seal would try to slip out, every time.

I follow the FSM instructions (VVT engine) which says to install the half moons onto the oil pump body and rear cover with the notch oriented correctly with sealant then apply sealant to the pan and install. Permatex 82180 Ultra Black Maximum Oil Resistance RTV from a powerbead can.

Used the same procedure, only sans MBSP on my 2000. No leaks yet.