Antifreeze
Thread Starter
Instructor
Joined: Nov 2001
Posts: 239
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From: Watertown SD
Antifreeze
Looking under the hood of my '85 tonight and found antifreeze laying on top of the passenger side of the intake. Checked the bolts on the runners and all seemed tight. Where do I look now? Checked the level in the radiator it was low.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
This isn't something you want to put off or it could kill your bearings.
Which part of the manifold? If it's not from the tstat housing, then it's an intake gasket leak, which means it's just as likely leaking into your lifter valley. Check for corrosion around the coolant port near #2 and #8 cylinder.
To confirm this, let your car sit for a day and then drain 1 cup of oil from the pan into a clean, dry, clear container. You're looking for water in the oil. If there's any in there, change the oil asap and run the engine to circulate the fresh oil (gets any coolant out of the bearing surfaces where it will destroy them if it sits there). Then you'd need to change the intake base.
This is especially a problem on 85s where the cast iron head corrodes the aluminum intake base. I know this first hand.
Which part of the manifold? If it's not from the tstat housing, then it's an intake gasket leak, which means it's just as likely leaking into your lifter valley. Check for corrosion around the coolant port near #2 and #8 cylinder.
To confirm this, let your car sit for a day and then drain 1 cup of oil from the pan into a clean, dry, clear container. You're looking for water in the oil. If there's any in there, change the oil asap and run the engine to circulate the fresh oil (gets any coolant out of the bearing surfaces where it will destroy them if it sits there). Then you'd need to change the intake base.
This is especially a problem on 85s where the cast iron head corrodes the aluminum intake base. I know this first hand.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
I'd like to see this pic. None of the 85s I've seen have the metal steam vent line there. The intake manifold isn't even cast for it.
Thread Starter
Instructor
Joined: Nov 2001
Posts: 239
Likes: 1
From: Watertown SD
Here's the pic of the area. The part I am refering to is the small one just to the left of the horizontal torx bolt. It is attached to the plate that bolts to the manifold.
Last edited by polish41; Jun 13, 2007 at 07:19 PM.
Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
That is not a coolant line. It's for the EGR. I was referring to a small 1/4" black line that goes from the intake base near the distributor to the upper heater hose on later L98s.
If yours doesn't have this, you have an intake gasket leak. See my first post and fix it asap or you'll be popping new bearings in your motor.
If yours doesn't have this, you have an intake gasket leak. See my first post and fix it asap or you'll be popping new bearings in your motor.
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Team Owner
Joined: May 2002
Posts: 24,337
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Make sure to use "The Right Stuff" rtv on the front and back walls of the block/intake seal. Throw away the little gasket strips that come in the kit for this. Run a 3/16" bead of RTV across the top of each wall and 1/2" up the heads.
Also some people use a small punch to dimple the intake and/or block surfaces to give the rtv something to bite into.
In addition to that, there is some slop in the bolt holes. Try to position the intake base to the rear as much as possible to get the best seal. Aim for this position before setting it into the RTV. Once it's set in the RTV you want to avoid shifting it around. If you screw up, pick it up, clean the surfaces off and try again.
Also some people use a small punch to dimple the intake and/or block surfaces to give the rtv something to bite into.
In addition to that, there is some slop in the bolt holes. Try to position the intake base to the rear as much as possible to get the best seal. Aim for this position before setting it into the RTV. Once it's set in the RTV you want to avoid shifting it around. If you screw up, pick it up, clean the surfaces off and try again.
Drifting
Joined: Feb 2003
Posts: 1,614
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From: Davis CA
My 86 iron head has a coolant attachment in this area as Central Coaster described. It is an tube to which a hose is attached and it runs to a T into the heater line along the passenger side fender. The tube should come into the intake just behind the EGR tube (the one with the silver sleeve over it). Check this first because it is easy to fix and a hose leak in that area could create the pool that you see.