ZZ4 Owners-HELP
Thread Starter
Racer
Joined: Jan 2001
Posts: 334
Likes: 1
From: Averill Park N.Y.
ZZ4 Owners-HELP
I installed my ZZ4 last year with a Holley Avenger on it.
I've been getting a puddle of oil on each side of the carburetor (more on the passenger side) in the pockets where the center manifold bolts are.
I pulled the manifold bolts, no oil coming up from them. Valve cover gaskets are dry. Almost seems to be coming from the carburetor.
Pulled the carb and found (2) 3/8" dia. holes in the floor of the manifold.
The hole in the lower level has oil in it. I remember this topic coming up before, but I don't remember the outcome.
Does anybody know what these holes are for or why there is oil in one of them? Also has anybody else had oil on the manifold next to the carb?
Thanks, in advance!
:confused:
I've been getting a puddle of oil on each side of the carburetor (more on the passenger side) in the pockets where the center manifold bolts are.
I pulled the manifold bolts, no oil coming up from them. Valve cover gaskets are dry. Almost seems to be coming from the carburetor.
Pulled the carb and found (2) 3/8" dia. holes in the floor of the manifold.
The hole in the lower level has oil in it. I remember this topic coming up before, but I don't remember the outcome.
Does anybody know what these holes are for or why there is oil in one of them? Also has anybody else had oil on the manifold next to the carb?
Thanks, in advance!
:confused:
Le Mans Master
Joined: Aug 2000
Posts: 9,662
Likes: 7
From: Semper ubi, sub ubi
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: ZZ4 Owners-HELP (Ken74Conv)
Ken, I haven't seen that on my ZZ4, although my manifold had the hole in the bottom, there is no oil in it. The guys at Pace Performance told me the hole is supposed to be there.
Clean the oil up and try and figure out where it is coming from by covering the bolt heads with a piece of cloth held down with tape. Drive it for a while and see if the oil is seeping out of the manifold bolt holes. If it isn't then try along the edge of the rocker covers.
Another posibility is that the oil is coming from another source and getting blown back up there, by the fan.
Are you using a breather or do you have a vent from the valve cover into your air cleaner? It could be dripping out of the breather vent line to air cleaner if you have one of those.
Clean the oil up and try and figure out where it is coming from by covering the bolt heads with a piece of cloth held down with tape. Drive it for a while and see if the oil is seeping out of the manifold bolt holes. If it isn't then try along the edge of the rocker covers.
Another posibility is that the oil is coming from another source and getting blown back up there, by the fan.
Are you using a breather or do you have a vent from the valve cover into your air cleaner? It could be dripping out of the breather vent line to air cleaner if you have one of those.
Drifting
Joined: Jul 1999
Posts: 1,542
Likes: 43
From: Plano TX
Re: ZZ4 Owners-HELP (Ken74Conv)
I ahev a ZZ4 and my understanding is that the holes in the bottom are for the EGR port. EGR lets exhaust gas into the intake charge. The ZZ4 heads do not have EGR ports to supply the exhaust gas, so in a ZZ4 engine the ports are blocked off by the cylinder head.
I also have oil on my middle intake bolts. I suspect that this is caused by not having silicone on the bolts beofre they were installed. Havne't done anything with it yet.
I say pull the bolts, clean them and the intake holes very well and apply silicone.
I have noticed when I start the engine I get the chevy blue oil smoke from the exhaust that does clear up. I thought these things have solved the valve guide/seal issues of the previous head designs?
I also have oil on my middle intake bolts. I suspect that this is caused by not having silicone on the bolts beofre they were installed. Havne't done anything with it yet.
I say pull the bolts, clean them and the intake holes very well and apply silicone.
I have noticed when I start the engine I get the chevy blue oil smoke from the exhaust that does clear up. I thought these things have solved the valve guide/seal issues of the previous head designs?
Burning Brakes
Joined: Oct 2001
Posts: 1,185
Likes: 0
From: New Wilmington PA
Re: ZZ4 Owners-HELP (DaveL82)
I ahev a ZZ4 and my understanding is that the holes in the bottom are for the EGR port. EGR lets exhaust gas into the intake charge. The ZZ4 heads do not have EGR ports to supply the exhaust gas, so in a ZZ4 engine the ports are blocked off by the cylinder head.
I had a similar surprise when I took my carb off awhile ago. They are perfectly normal. :cheers:
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