Thoughts on newly built motor oil leak

[moper]

Oil pressure has nothing to do with a rear main seal leak. Crankcase pressure or poor seal installation do. I built my run stand for the first fire. I can control the first fire, the cam break in, swap valve springs easy, retorque heads, do some basic tuning, and address any leaks before the customer get's their hands on it. The best case scenario for any buyer is have it run before you get it.

 

[oldbee]

6 & 12 clocking? I always went like 6&2 Or thereabouts.

 

[440beep]

Well I definitely think I'm going to take the time this go around and have it test run first. So it sets my summer back even further, at least I should know the motor is fine.

Oil pressure has nothing to do with a rear main seal leak. Crankcase pressure or poor seal installation do. I built my run stand for the first fire. I can control the first fire, the cam break in, swap valve springs easy, retorque heads, do some basic tuning, and address any leaks before the customer get's their hands on it. The best case scenario for any buyer is have it run before you get it.

 

[moper]

Wise choice. Plus it means for the good weather you can enjoy it a little and remember why you wanted to spend the moneyon it.

 

[440beep]

Pulled the motor last night and there's quite the pool of oil on the rear cam seal, plus down around bottom of motor. Looks to be an oil stream coming down from RMS, but hard to tell if it's the cam seal or something else. Wonder if it's the rear cam seal based on amount of oil sitting there? Everything else is dry.

 

[miller]

Everything else looks dry. Yeah, I'd say the cam seal.
Did you put any sealant on it? I always use Indianhead Shellac sealer on those cup-type plugs.

 

[moper]

That "cam plug" looks like a std deep freeze plug was used there. It should be a shallow plug if that is used. I always use a disc-type cupped plug that is put in place and them dimpled in the center to properly seal against the small step at the cam bearing boss and not hit the back of the cam. That's what the factory used on the early and mid-production engines but not all suppliers include that type of plug in the hardware packages.

 

[440beep]

Do you have a picture of the disc type cupped plug?

That "cam plug" looks like a std deep freeze plug was used there. It should be a shallow plug if that is used. I always use a disc-type cupped plug that is put in place and them dimpled in the center to properly seal against the small step at the cam bearing boss and not hit the back of the cam. That's what the factory used on the early and mid-production engines but not all suppliers include that type of plug in the hardware packages.

 

[440beep]

Found the oil leak. Pressurized the crank case with 20psi of air, and heard the air hiss coming out the upper corner of the RMS. So now it's examining and replacing that side seal. I'm using the Mancini billet RMS with the two seals per side. Considering going back to the original single side seal.

 

[Bee1971]

Black RTV down the sides along with those two side o rings , a dab of Black RTV on each corner top where the o rings push in

Then I clock my Seal Halves at 12 and 6

Do not use RTV on the ends of seal halves

When I have both seal halves installed around the crank , I used the alignment studs supplied with the Mancini Retainer , slid the Retainer in place DRY using the alignment studs to make sure the seal halves where in perfect alignment with the Retainer , that way when I slid the Retainer in place with the o rings and RTV and bolts to torque down , I was good to go

I have done three motors this way for myself and friends

 

[moper]

This is a small block kit but the cam sealing plug are the same big or small. Earlier uses the disc, later uses the cupped plug with the flange on it (both silver in this pic)