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Just fired up my 406!

  
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Just fired up my 406!

 
69GTOby 69GTOby
Guru | Posts: 1117 | Joined: 02/09
Posted: 07/30/14
06:16 PM

Hey guys.  I finally finished my 406 build.  Well... it runs that is.  It will need some little tweaks, but it's alive!  Cool

It's my 406 bottom end with crappy pistons .040 down the hole with 8 VR's, new oil pump, rings, and bearings, with rebuilt big valve 75cc heads, ported and polished, and an open plenum intake.  It got my Bracket Master Lunati cam (the smaller one), double roller timing set at 0*/straight up.  It should be about 8.8:1 SCR.

I wonder what kind of power this will make, 350hp, 400 ft lbs...?  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

69GTOby 69GTOby
Guru | Posts: 1117 | Joined: 02/09
Posted: 08/31/14
05:45 AM

Hey guys.  I got the engine in the car.  It runs great! But, when I first drove it, the engine started smoking from the passenger side.  I found a large pool of engine oil on the distributor pad!  

It always had >20 psi oil pressure at idle, and 65+ psi with throttle.  Anyway, I started it up to look for the source of the leak but couldn't really find it.  Oil was everywhere.  I cleaned it up, started it, and looked again, but I no avail.  I think it has to be warmed up with thinned out hot oil and rpms...

Where could this substantial leak be coming from??  
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1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

gtojack1366 gtojack1366
Guru | Posts: 1265 | Joined: 11/09
Posted: 08/31/14
11:39 AM

Oil could be leaking from back of valley pan or the oil plug by the distributor or distributor gasket .  

69GTOby 69GTOby
Guru | Posts: 1117 | Joined: 02/09
Posted: 09/01/14
05:49 AM

There is so much oil that it seems like it's coming from a pressurized source.  The galley plug is in there.  I will check to make sure it's tight.  The distributor has a new gasket and it's snug, but I will check that again.  

Could it be possible that I damaged the distributor putting it in?  I suspect maybe I cracked it putting the engine in because I had it at an extreme angle...  Hmmmm  
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1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

gtojack1366 gtojack1366
Guru | Posts: 1265 | Joined: 11/09
Posted: 09/01/14
07:06 AM

I never seen a cracked distributor and I beat on a lot of distributors getting them out . If it leaks that bad it should be easy to find .Try cleaning the oil up when it's hot to see where it's coming from .  

69GTOby 69GTOby
Guru | Posts: 1117 | Joined: 02/09
Posted: 09/01/14
07:11 AM

You know...  I sprayed brake parts cleaner all around there with the engine running hoping to clean away the oil so as to see the leak and the thing caught fire! Lol, oops.  I'm going to check everything again...  
****
1969 GTO resto in progress. '76 350+.060, #13 heads, 9.2:1 CR, Lunati cam, Edelbrock Performer, 750 Holley, HEI, Ram Air manifolds, 2 1/2" exhaust. TH400 trans w/shift kit and 2400 stall.  235/60/15 front, 275/60/15 rear on Rally II 15X7s.  GM 12 bolt posi with 3.73's.

Brazil Brazil
Addict | Posts: 3954 | Joined: 06/09
Posted: 09/01/14
07:14 AM

Could be, i've bent my distributor shaft before while installing the engine - didn't notice it was pushing against the firewall. But not enough to make anything leak oil. Can you clean it all off and run it just long enough to maybe detect the first little bit of leakage before it has time to cover too much area?

Are you pretty sure it's coming from the top? Over tightening the valve covers and oil pan are the usual suspects, then the rear main oil seal. But if it's puddeling up around the distributor, Jack's suggestion about the valley pan might be the source. might have to pull the dist and see if it's damaged. On my last few installs I've left it out till the engine is in. At least your car is running great, congratulations! Seems they always have to have a leak somewhere at first just to mess with you!  

gtojack1366 gtojack1366
Guru | Posts: 1265 | Joined: 11/09
Posted: 09/01/14
03:37 PM

Clean with cleaner when cold not running then get hot use rags and a flashlight .Might be hard to see with clean oil in engine . You could put die in oil and use a ultraviolet flashlight .  

shyrgfuh3 shyrgfuh3
Enthusiast | Posts: 475 | Joined: 11/13
Posted: 09/01/14
06:50 PM

do you have the paper gasket non the distributor?

most likely it is the valley pan or valve covers.

the cam and lifters hurl oil at that valley pan.
.  

Brazil Brazil
Addict | Posts: 3954 | Joined: 06/09
Posted: 09/02/14
12:37 AM

I've always had a prob with those puny little gaskets too. I've used two before, and it wasn't thick enough to effect the gear contact. Did stop the leak though.  

owsley owsley
New User | Posts: 10 | Joined: 08/14
Posted: 09/12/14
07:19 AM

i always use high tack on the valley pan gaskets. you might use a small screwdriver or pick to make shur the gasket didn't slip!  
work = fun when you are working on old pontiacs!