The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 03-07-2013, 07:53 PM   #1
cwilkie
Chance
 
cwilkie's Avatar
 
Join Date: Sep 2001
Location: Belcourt ,ND, USA
Posts: 750
Antifreeze and oil

I think I have a problem. I was pushing snow this week after th big North Dakota blizzard and I thought it would be a good idea to check the oil and antifreeze. Both are a little low. No biggie. I decided to add oil and antifreeze. Today I started the truck to go fill up on gas and I decided to pop the hood when I got back. On the intake by cylinder 1 there was a small pool of oily antifreeze. Near cylinder 5 & 7 there was a small pool of oil. Now my questions is does this mean I have a bad gasket or could the intake be cracked. The truck has a fresh 427bb where all the cast iron was checked for cracks by the machine shop before assembly and it did not leak for almost a year until now. I can change an intake without too much trouble but I do not have another cast iron intake lying around. Thanks guys.
Posted via Mobile Device
__________________
1968 Chevrolet Stepside
BB 396 w/TH400

1972 Chevrolet 3/4 Ton 4x4
BB 496 w/TH400
cwilkie is offline   Reply With Quote
Old 03-07-2013, 08:01 PM   #2
geezer#99
Registered User
 
geezer#99's Avatar
 
Join Date: Aug 2009
Location: Bowser
Posts: 13,731
Re: Antifreeze and oil

Did you use sealer on the intake bolts?
geezer#99 is offline   Reply With Quote
Old 03-07-2013, 08:01 PM   #3
TBONE1964
Cluster King
 
TBONE1964's Avatar
 
Join Date: Nov 2012
Location: Junction City, OR
Posts: 5,263
Re: Antifreeze and oil

The most likey cause of your oil on the intake is from oil seeping past the threads on the intake bolts. some of the intake bolts thread though an open hole right into the lifter galley and it is common for oil to work it's way through the threads of the bolt and into the valleys near the bolts.

The fix is to remove each bolt, clean and apply a small amount of high temp rtv onto the threads.

The antifreeze near #1 may be a t-stat gasket or upper radiator hose leak. If you can get your hands on a pressure tester, you can pump it up to 15 psi and see where the leak is coming from. Maybe just a loose hose clamp.

I don't think you need to worry about replacing the intake unless it is cracked somewhere and from what you stated, yours should be good.
TBONE1964 is offline   Reply With Quote
Old 03-07-2013, 08:36 PM   #4
cwilkie
Chance
 
cwilkie's Avatar
 
Join Date: Sep 2001
Location: Belcourt ,ND, USA
Posts: 750
Re: Antifreeze and oil

I do not recall if the engine builder used sealer. Do you know the torque setting for the intake? My book is packed away.
Posted via Mobile Device
__________________
1968 Chevrolet Stepside
BB 396 w/TH400

1972 Chevrolet 3/4 Ton 4x4
BB 496 w/TH400
cwilkie is offline   Reply With Quote
Old 03-07-2013, 08:39 PM   #5
TBONE1964
Cluster King
 
TBONE1964's Avatar
 
Join Date: Nov 2012
Location: Junction City, OR
Posts: 5,263
Re: Antifreeze and oil

Intake bolts for a BBC are 30-35 lbs torque. I would start in the middle and go in a circle until you reach the ends.
TBONE1964 is offline   Reply With Quote
Old 03-07-2013, 08:43 PM   #6
7dee2
Registered User
 
7dee2's Avatar
 
Join Date: May 2011
Location: Syracuse, Utah
Posts: 1,986
Re: Antifreeze and oil

Quote:
Originally Posted by TBONE1964 View Post
The most likey cause of your oil on the intake is from oil seeping past the threads on the intake bolts. some of the intake bolts thread though an open hole right into the lifter galley and it is common for oil to work it's way through the threads of the bolt and into the valleys near the bolts.

The fix is to remove each bolt, clean and apply a small amount of high temp rtv onto the threads.

The antifreeze near #1 may be a t-stat gasket or upper radiator hose leak. If you can get your hands on a pressure tester, you can pump it up to 15 psi and see where the leak is coming from. Maybe just a loose hose clamp.

I don't think you need to worry about replacing the intake unless it is cracked somewhere and from what you stated, yours should be good.
Some of these intake manifold bolts also go into the coolant passages so do what TBONE1964 suggests with the thread sealer but I would start in the middle and work your way outward then re-torque the intake manifold bolts (cast iron head) 25 - 30 ft.-lbs. in the correct sequence. If it still leaks water check that the thermostat housing is sealed as suggested. Should not be a biggie!
Attached Images
 
__________________
Brett
67 Camaro SS: 67 Camaro Build
72 Cheyenne/C10 Super 115" Fleetside: 72 C10 Build
72 Cheyenne/K30 Super 133" Longhorn DRW: 72 K30 Build SOLD

YouTube: https://www.youtube.com/@6dee7-7dee2
7dee2 is offline   Reply With Quote
Old 03-07-2013, 08:55 PM   #7
cwilkie
Chance
 
cwilkie's Avatar
 
Join Date: Sep 2001
Location: Belcourt ,ND, USA
Posts: 750
Re: Antifreeze and oil

Awesome. I just went out to check and the thermostat housing is leaking so that explains the antifreeze. It has an o-ring so I will take it off to clean it and put it back on. I will follow your instructions when I re torque the intake bolts.

I guess it looked worse at first site than it really is.

Where I live a plow or a bobcat is a must in the winter. Thanks for the great advice.
Posted via Mobile Device
__________________
1968 Chevrolet Stepside
BB 396 w/TH400

1972 Chevrolet 3/4 Ton 4x4
BB 496 w/TH400
cwilkie is offline   Reply With Quote
Old 03-07-2013, 08:56 PM   #8
cwilkie
Chance
 
cwilkie's Avatar
 
Join Date: Sep 2001
Location: Belcourt ,ND, USA
Posts: 750
Re: Antifreeze and oil

Awesome. I just went out to check and the thermostat housing is leaking so that explains the antifreeze. It has an o-ring so I will take it off to clean it and put it back on. I will follow your instructions when I re torque the intake bolts.

I guess it looked worse at first site than it really is.

Where I live a plow or a bobcat is a must in the winter. Thanks for the great advice.
Posted via Mobile Device
Posted via Mobile Device
__________________
1968 Chevrolet Stepside
BB 396 w/TH400

1972 Chevrolet 3/4 Ton 4x4
BB 496 w/TH400
cwilkie is offline   Reply With Quote
Old 03-07-2013, 10:10 PM   #9
Sammy
Registered User
 
Join Date: Apr 2000
Location: Bonne Terre, Mo
Posts: 3,005
Re: Antifreeze and oil

If your using a aftermarket intake that isn't cast iron make sure you check the torque from the manufacture's chart. Eldebrock aftermarket intake torque sequence and specs are much different than your stock cast iron.
__________________
'69 Chevy Long Fleet & '71 GMC Short Step & Project "ODD BALL"


"You can wash a pig, soak it in most expensive perfume. In the end it is still just a pig."

ODD BALL build thread http://67-72chevytrucks.com/vboard/s...d.php?t=478629"
Sammy is offline   Reply With Quote
Old 03-07-2013, 10:51 PM   #10
cwilkie
Chance
 
cwilkie's Avatar
 
Join Date: Sep 2001
Location: Belcourt ,ND, USA
Posts: 750
Re: Antifreeze and oil

I have a standard cast iron intake.
Posted via Mobile Device
__________________
1968 Chevrolet Stepside
BB 396 w/TH400

1972 Chevrolet 3/4 Ton 4x4
BB 496 w/TH400
cwilkie is offline   Reply With Quote
Old 03-08-2013, 04:27 AM   #11
piecesparts
Parts and more parts
 
piecesparts's Avatar
 
Join Date: Nov 2003
Location: Lebo, Kansas (middle of nowhere
Posts: 6,821
Re: Antifreeze and oil

Here is something to think about, You need to wipe down the intake and make sure it is clean, start the truck on a cold morning and watch the T/stat housing to see if it leaks when the metal in the intake and the housing are cold. There tends to be leakage around these connection points, due to the dissimilar metals in the two item and that is where your antifreeze is coming from.
__________________
Frank
piecesparts is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 11:50 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com