Topic Options
#2462631 - 03/07/18 01:14 PM Weird place for a oil leak, Built a Scat 408 engine for a bu
727builder Offline
super stock

Registered: 02/03/06
Posts: 1005
Loc: Tennessee
Am I the only one to run into this? A friend bought a Scat rotating assembly from Jegs for a 408 street engine. I assembeled it. Got it together on the stand and primed it. No leaks. Put it in car and fired it up and looked. No leaks. While breaking in the cam for about 20 mins. We shut off the car and raised the lift and noticed oil on the ground. Was coming from bellhousing. Pulled trans. And primed engine again while looking at the back of the block. Cam plug and the 3 pipe plugs all in place and tight with no leaks anywhere. Then I noticed oil from the pilot hole in the back of the crankshaft. frown Video--->> https://youtu.be/lOLVuJM0uJs

Top
#2462635 - 03/07/18 01:20 PM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
Bad340fish Offline
master

Registered: 01/20/03
Posts: 5635
Loc: Tulsa OK
Yikes, they drilled that one a little deep it looks like.

The right thing to do is replace the crank of course, but if it were mine I would be trying to put a freeze plug or something in there if it is an automatic car and doesn't need the pilot hole.
_________________________
68 Barracuda Formula S 340

Top
#2462665 - 03/07/18 01:49 PM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
EV2Bird Offline
No more politics

Registered: 06/23/14
Posts: 3740
Loc: Kansas Roads Between 0 and 140...
If it were bought through jegs id get with them, or scat directly Thats beyond the end uses expectations of cleaning and inspecting new parts.

Sucks to pull it down but id not expect to have to be out more then labor in the whole mix, since it was a kit you should have the card or they already should know what your bob weight is.

Id just not put a plug in it, for many reasons but thats just me.

Top
#2462697 - 03/07/18 02:55 PM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
madscientist Offline


Registered: 09/17/14
Posts: 1982
Loc: Washington
That's junk. I can't tell if it's too deep or the crank has porosity in it.

I'd be replacing that in a hurry. Unacceptable.


On top of all that, the finish machine work looks like it was done by a drunken retarded ham fisted polar bear using dull tools.


Sucks bad but I wouldn't fix it. And if it's a cast crank I'd upgrade to a forged one.
_________________________
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston

Top
#2462889 - 03/07/18 08:53 PM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
Cab_Burge Online   content
I Win

Registered: 08/23/03
Posts: 30808
Loc: Bend,OR USA
Originally Posted By 727builder
Am I the only one to run into this? A friend bought a Scat rotating assembly from Jegs for a 408 street engine. I assembeled it. Got it together on the stand and primed it. No leaks. Put it in car and fired it up and looked. No leaks. While breaking in the cam for about 20 mins. We shut off the car and raised the lift and noticed oil on the ground. Was coming from bellhousing. Pulled trans. And primed engine again while looking at the back of the block. Cam plug and the 3 pipe plugs all in place and tight with no leaks anywhere. Then I noticed oil from the pilot hole in the back of the crankshaft. frown Video--->> https://youtu.be/lOLVuJM0uJs
shock puke
Don't we hate Murphy whiney
Sorry for your issues runaway
_________________________
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Top
#2463113 - 03/08/18 12:00 PM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
727builder Offline
super stock

Registered: 02/03/06
Posts: 1005
Loc: Tennessee
Showed video to guys at local race shop. They said the same thing. Porosity of the cast crank. They said the if the owner doesn't want to spend the extra money to replace it with a better steel crank? Put a freeze plug in to stop the leak and let it go. They showed me several cranks that was drilled to remove weight with freeze plugs put in the back. If anyone ever runs into crap like this? Only a Dorman 555-117 28mm freeze plug will fit.
And it's also Made in China

Top
#2463467 - 03/08/18 09:34 PM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
dezduster Offline
pro stock

Registered: 02/05/03
Posts: 1238
Loc: Nevada
I have a nagging leak at the back of my scat cast crank 408 2 pans 3 gaskets and I'm on the second rear main seal and still is leaking. Ill know where to look next!

Top
#2463658 - 03/09/18 09:19 AM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
Racer33 Online   content
member

Registered: 10/04/11
Posts: 155
Loc: Norfolk, NE
Aww crap. I was planning on ordering a rotating assembly from them. Now I'm nervous. Guess if I pull the trigger I now know the first thing to check

Top
#2463737 - 03/09/18 11:26 AM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
727builder Offline
super stock

Registered: 02/03/06
Posts: 1005
Loc: Tennessee
Glad I could help, Or warn others... Was a first for me. Never thought I would ever have to look in the pilot hole while priming a new engine.

Top
#2463841 - 03/09/18 01:44 PM Re: Weird place for a oil leak, Built a Scat 408 engine for a bu [Re: 727builder]
jbc426 Offline
master

Registered: 03/01/07
Posts: 2730
Loc: West Coast, USA
I believe Chevy LS motors have a freeze plug style plug in the back pilot hole from the factory. I saw several write-ups about fixing the oil leaks there, while searching for a mystery oil leak on an RB.
_________________________
1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 3.73s
1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3600 stall lock-up converter and 3.91's (closest thing to an automatic 5 speed going)

Top

Advertisement
Sponsored Link
Forum Stats
25,347 Registered Members
32 Forums
190,226 Topics
2,219,646 Posts

Most users ever online: 1,424 @ 06/20/18 07:18 PM
Moparts Newest Topics
Rough '70 GTX V code
by ChryCoGuy
Today at 11:26 AM
Wall Street Journal reviews past global warming predictions
by DaveRS23
Today at 09:58 AM
Big gas bare heads?
by fbs63
Today at 09:38 AM
Can this crack in this hemi block be repaired?
by Challenger 1
Today at 09:19 AM