Hey guys,
Fully rebuilt motor went in and it ran well! I have a trickle of oil seeping out by the alternator tab (as far as I can tell). I thought I followed the guidelines to the T, took my time, made sure i was careful with clean surfaces and laying down the silicone sealant. But now I wonder what I could have done differently and whether or not my methods will promote a leak free experience after all is said and done.

I ordered new gaskets for ALL THE THINGS just in case, because this is probably the last chance I get to pull the motor: cam seals, crank seal, oil pump pickup gasket, oil pan half moons, and high pressure side o-ring.

I am only creating this thread because I had thought I did everything right the first time around, I'm just seeking any master tips or tricks that may help ensure success. Nothing is more frustrating that struggling to get a motor to work, only to find it has to come out again... so obviously I missed something and I don't want to repeat my mistakes not knowing any better. I know some of you can sympathize so I just seek some further guidance.

The Symptoms
Along the oil filter and oil feed is bone dry. I had the A/C bracket leak, but this was rectified by harvesting a bolt off another motor. Oil is noticed to be dripping from the passenger side, only when the engine is running, by the alternator bracket (above the oil pan seal), and then will settle under the pulley. This leaves me to believe it's the block/pump interface and not the crank seal, but I cannot be too sure.

Region under the crank seal does not experience immediate wetting; but perhaps oil is just being carried up in the direction of the pulley rotation, only to deposit once the motor is stopped.

Water pump area is dry, I don't notice anything dripping down from cam seals, but it's difficult to inspect behind the black plate that affixes the timing cover


The game plan:
Use UV dye to be sure where it's coming from and take photos since I cannot take an image of clear oil on a gloss black block. If it proves to be an accessible leak, fix accordingly.

Maybe pull the SuperMiata damper off (after finding a gear puller) to inspect crank seal to replace and test while the engine is still in place (best case scenario)

Pull the motor and pull the pan and pump, scrape, and try again (but upside down?) at risk of screwing up half-moon seal alignment



My question to you folks in earnest:
1) How liberal can you be with the sealant on the oil pump to block?

2) When re-re-re-re-sealing the oil pan, how do you ensure the half moons are not going to get crimped or come out of alignment? Or should I flip the motor upside down on a stand for this to set the oil pan.

3) What is the best way to remove the silicone aside from razor blade; do I take a dental pick and risk scratching the surface up along the machined grooves?







Cliffnotes:

Mysterious oil leak, prominent around lower alternator region, above oil pan. I thought I sealed the oil pump and pan correctly, just seeking input on sealing techniques.

 

The motor should be upside down for installing the oil pump, pan, and rear main. Not necessary for the pump and rear main, but makes it easier.

Some years require an o-ring between the pump and gasket, I know at least the 90-93s did. There's a few small groves on the pump, I use these to make a line of RTV to follow the shape of the gasket. Then place the o-ring, gasket, and then more RTV on the top of the gasket.

For the pan, once there is a ring of RTV around the entire edge, the RTV will hold the half moons in place, and there's a little **** on each to center them. Keep all surfaces clean with rubbing alcohol, including the baffle. This helps RTV on any surface (pump, rear main) seal better.

 

Thanks Curly,
I got a Boundary Engineering pump and it does have the grooves for the RTV. I just wonder if the o-ring slipped or didn't seal properly as it's leaking only while the motor is on. I didn't have any additional gasket between the RTV or block.

This is all speculation until I'm able to observe what has happened with UV ink. If it were the oil/crank seal, would it leak even if the car were turned off? Pressure dependency leads me to the actual interface seal. I used a continuous bead around the oil pump and finger tightened the bolts before torquing it down. Should I be a bit more liberal with the amount and just tighten it in one go?

 

I have felt your pain. Here's my saga . . . ended up being camshaft seals which is way easier to fix than an oil pump. Use that dye. It's your friend.

https://www.miataturbo.net/general-m...mp-leak-70789/

As for proper sealing method for any given Miata oil pump, see pictures in post #19:

https://www.miataturbo.net/general-m...uestion-26178/

For getting every bit of RTV off metal surfaces, wire brushes (preferably the stainless type -- bristles are softer) works like a charm for me. Position your work so that gravity causes the RTV bits to fall outside the engine. Tiny bits of RTV inside an engine can be nasty.

 

I'd try installing the oil pump gasket first.

Edit: I like that post, but I'm not sure I agree with the pictures. My 1.6 has grooves for RTV, which, according to those pictures, means I don't need an oil pump gasket. Yet they're included in every assembly picture, instructions, and gasket kit.

 

Hornetball, where did you notice the oil pooling up? I thought about the cam seals but didn't see anything and the top of the waterpump is clear. I guess the only real way to see is by using that dye.

I remember reading up on how to properly seal the oil pump and from that very thread thought that the RTV sealant on the grooves would be the protocol. I didn't have a paper gasket, which now I'm seeing as yet another way to seal the pump IN ADDITION to the RTV.

I appreciate the responses. I've never laid hands on a paper gasket for the pump. I just don't want to fail again doing the same thing I though would work the first time. But I guess I need to check first before I assume the worst.

Radiator has to be removed to fit the gear puller?

 

+1 on cam seals, that's what my leak was. I ended up doing a front main seal and camshaft seals at the same time when i tore it down again. Now I ONLY use oem seals and have the FM seal installer kit. No leakz.

Edit: also in for proper oil pump installation tips, as I'm going to be doing this soon enough myself.

 

But where were you all noticing the oil collecting? I'm hoping it's as simple as the front seals... I'd love to use the FM tools I purchased also lol

I'm damned excited thinking about getting this back on the road, break in the motor and clutch.

 

It looked for all the world like an oil pump leak. The oil was flowing along corners and cracks -- no pooling. Until I did the dye and took off all the TB covers, I didn't have a chance of seeing that it was the camshaft seals.

 

Another thing, make sure you use the right bolts. Some bolt lengths will bottom in the holes if you get them swapped around. You might think you have the right torque, but it's not torqued at all.

 

on mine i could have easily mistook it for an oil pump. It came down from the cam seals, pooled in all the nooks and crannies on the way down, and ended up dripping off the bottom of the oil pan.

 

Alright this gives me some hope. I'll try to take some pics whenever I do the UV stuff

 

My brand new china cam seals are so bad that oil gets onto the cam gears, then the timing belt and gets sprayed onto the underside of my hood and across both shock towers in a 2-3" wide stripe.

 

Yip, same cam seals I used. I will NEVER AGAIN use ebay front/rear main or cam seals, or anything that isn't easily replaced really.

My cam seals were PUKING oil, so much I didn't even think it was possible for them to leak that much. Yip, it is.

 

how do you even check your rear main seal? look for oil pouring out your clutch fork?

 

Nonono. 90-93 had a paper gasket and no o-ring. 94-05 had an o-ring, no gasket, and RTV. If your pump has a groove line for RTV and a channel for an o-ring around the pressure port, don't use a gasket.

 

Do you recommend using RTV on both sides the O ring seal like Curly mentioned above?

Also, pickup tube. Paper gasket, or paper gasket + rtv ?

 

No in both cases. Using RTV with a paper gasket is kludgy as hell. Use RTV -or- a paper gasket, never both.

 

I almost always use a very light amount of rtv on all my paper gaskets making them tacky. I put rtv between my fingers and rub it across the gasket... Maybe this is bad practice as It does make replacing gaskets take more work when I have to clean the surface for the next one but Its always created a great seal.

I was taught this at a very young age from my father. There are a few applications I don't do this but it is my standard practice.

 

There's a weep hole at the bottom of the bellhousing. If you are sure nothing else on the back of the engine is leaking (i.e., valve cover gasket, CAS O-ring, etc.) and you have motor oil coming out of that weep hole, there's a good chance you've got a Chinese rear main seal.

Cheapo gaskets were on the crate motor I bought a couple of years ago. I've had the pleasure of replacing the cam seals, rear main seal and headgasket. I keep telling myself it's therapy. Rosenthal loves me.