Engine smoke when whacking throttle
Thread Starter
Instructor
Joined: Sep 2008
Posts: 233
Likes: 17
From: Macon GA
Oil and water were clean. No "chocolate milk" and a good coolant chemical "block test". That said I think I have found the problem. Heads were not “ported” but the were port matched to FelPro 1206 intake gaskets. Intake is an Eddy 2701 intake that I had on the shelf. When we pulled the intake off and inspected the gaskets the top of the intake runner only matched the head by only 1/16” or less in some places. Looks like there may have been some head/intake mismatch or leaking gasket on #4 & #6. Original compression test and leak down tests were good so I now wondering if I should go ahead and pull the head to double check the head gasket. Will use different intake on the rebuild.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Oil and water were clean. No "chocolate milk" and a good coolant chemical "block test". That said I think I have found the problem. Heads were not “ported” but the were port matched to FelPro 1206 intake gaskets. Intake is an Eddy 2701 intake that I had on the shelf. When we pulled the intake off and inspected the gaskets the top of the intake runner only matched the head by only 1/16” or less in some places. Looks like there may have been some head/intake mismatch or leaking gasket on #4 & #6. Original compression test and leak down tests were good so I now wondering if I should go ahead and pull the head to double check the head gasket. Will use different intake on the rebuild.
I think you found the problem though.....the 1206 is a rather large port.....stock style or 1204 would not seal all the way around the port entrance.
Good luck!
Jebby
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Just my opinion but, I see no reason to pull the head. No indication of a faulty head gasket. Great compression test. Great leak down test.
As far as Intake gaskets, always better to order too small of port than too large of port, if given a choice. A razor sharp Exacto knife makes quick work of a gasket material hanging in the port.
Of all the gaskets on a car, I find the Intakes the most intimidating to order. Not only do they have to match the head, but they should be close to fitting the manifold too. Then there's also the thickness to ponder over.
One size does NOT fit all.
Looking at Summits Intake gaskets list, take your time measuring height and width, thickness. Don't forget a good gasket sealer too.
As far as Intake gaskets, always better to order too small of port than too large of port, if given a choice. A razor sharp Exacto knife makes quick work of a gasket material hanging in the port.
Of all the gaskets on a car, I find the Intakes the most intimidating to order. Not only do they have to match the head, but they should be close to fitting the manifold too. Then there's also the thickness to ponder over.
One size does NOT fit all.
Looking at Summits Intake gaskets list, take your time measuring height and width, thickness. Don't forget a good gasket sealer too.
Last edited by HeadsU.P.; Jan 17, 2020 at 04:09 PM.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Just my opinion but, I see no reason to pull the head. No indication of a faulty head gasket. Great compression test. Great leak down test.
As far as Intake gaskets, always better to order too small than too large if given a choice. A razor sharp Exacto knife makes quick work of a gasket hanging in the port.
Of all the gaskets on a car, I find the Intakes the most intimidating to order. Not only do they have to match the head, but they should be close to fitting the manifold too. Then there's also the thickness to ponder over.
One size does NOT fit all.
Looking at Summits Intake gaskets list, take your time measuring height and width, thickness. Don't forget a good gasket sealer too.
As far as Intake gaskets, always better to order too small than too large if given a choice. A razor sharp Exacto knife makes quick work of a gasket hanging in the port.
Of all the gaskets on a car, I find the Intakes the most intimidating to order. Not only do they have to match the head, but they should be close to fitting the manifold too. Then there's also the thickness to ponder over.
One size does NOT fit all.
Looking at Summits Intake gaskets list, take your time measuring height and width, thickness. Don't forget a good gasket sealer too.
1204, 1205, 1206 small, medium, large....
His are ported for a 1206 so that is the one.
Jebby
Last edited by Jebbysan; Jan 15, 2020 at 03:56 PM.
Team Owner
Joined: Sep 2002
Posts: 38,360
Likes: 2,085
From: California
Dudes!!!!!! Also along with the intake gasket sizing!
Run thru the cylinder head torques first, before pulling the head. Torque sequence and test drive.
Run thru the cylinder head torques first, before pulling the head. Torque sequence and test drive.
Last edited by TCracingCA; Jan 16, 2020 at 01:07 AM.
Thread Starter
Instructor
Joined: Sep 2008
Posts: 233
Likes: 17
From: Macon GA
Sorry for the delay. Life has a bad habit of getting in the way. Only thing new is when I examined the intake gasket with a magnifying glass there was only 1/16 inch or less of mating surface between the intake and the head. When I dry fitted the intake on the engine I could run a .030 feeler gauge in the gap along the top edge of the intake. Bottom line is the intake appears to be physically too small to seal with heads port matched to the 1206 gaskets. Monday I will go to Summit and look at intakes to find one that will seal properly. Nothing wrong with the Eddy 2701 intake, it just works best with stock non-port matched heads.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
As the little old lady says in the church basement on Sunday night: BINGO!
You have found the issue and you are a lucky dog living so close to McDonough Summit. (I go every April)
Don't know if the "counter guys" there are good at matching Intake gaskets for you or not. Certainly a lot of choices as far as width, length. And do you want to block off the heat passage? I would in GA.
Using Summits search feature, I think I would click on about five gaskets that have potential. Using the compare feature and if you have a printer, make a copy to take with you.
You have found the issue and you are a lucky dog living so close to McDonough Summit. (I go every April)
Don't know if the "counter guys" there are good at matching Intake gaskets for you or not. Certainly a lot of choices as far as width, length. And do you want to block off the heat passage? I would in GA.
Using Summits search feature, I think I would click on about five gaskets that have potential. Using the compare feature and if you have a printer, make a copy to take with you.
Last edited by HeadsU.P.; Jan 17, 2020 at 08:53 AM.
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Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
deja vu all over again (well, kinda sorta)
I, for one, was thrown for a loop by the "white smoke" symptom and crappy plugs on # 4 & #6 (middle, right bank) and "water droplets" symptoms in OP's post #1.
So it seems motor's Not sucking oil (typically blue smoke) at leaking middle intake ports. Glad OP identified his problem.
Above Not same as, but reminds me of a gent, who (in his C3) had a good running, near new, unmolested ZZ4; but wanted more giddyup: he installed better heads and a bigger cam.
He installed a Howards (iron) roller (which soon failed but was replaced w/ steel). He also tried to install Brodix IK 200 heads with his OE ZZ4 intake: NO GO.
The Iron Killer 200s are manufactured w/ an approximate fit to a 1206. The ZZ4 intake's manufactured w/ an approximate fit to stock or 1204.
Outside of ZZ4 intake was too small to cover up the 200's big port openings.
Searched for intake that was (1) big enough to match 200's ports AND (2) would fit under hood AND (3) fit his good-running spreadbore QuadraJet: NO GO.
Easiest solution was return the IK 200s and install IK 180s (w/ smaller port openings): those fit his OE ZZ4 intake well. All was good until that POS iron roller soon failed.
So it seems motor's Not sucking oil (typically blue smoke) at leaking middle intake ports. Glad OP identified his problem.
Above Not same as, but reminds me of a gent, who (in his C3) had a good running, near new, unmolested ZZ4; but wanted more giddyup: he installed better heads and a bigger cam.
He installed a Howards (iron) roller (which soon failed but was replaced w/ steel). He also tried to install Brodix IK 200 heads with his OE ZZ4 intake: NO GO.
The Iron Killer 200s are manufactured w/ an approximate fit to a 1206. The ZZ4 intake's manufactured w/ an approximate fit to stock or 1204.
Outside of ZZ4 intake was too small to cover up the 200's big port openings.
Searched for intake that was (1) big enough to match 200's ports AND (2) would fit under hood AND (3) fit his good-running spreadbore QuadraJet: NO GO.
Easiest solution was return the IK 200s and install IK 180s (w/ smaller port openings): those fit his OE ZZ4 intake well. All was good until that POS iron roller soon failed.
Thread Starter
Instructor
Joined: Sep 2008
Posts: 233
Likes: 17
From: Macon GA
Finally got everything back together. Runs strong and no smoke. Apparent problem was the Eddy 2701 intake would not match up with the 190 heads that were port matched to Fel Pro 1206 gaskets. I went to Summit and looked at several intakes and ended up with an Eddy 7501 Air Gap. It was the only one I found that had enough material around the ports to match the 190/1206 heads. The 7501 also better matched the power curve of my Lunati cam. Had to use a drop base air cleaner to clear the hood, but I had one so issues there. THANKS TO ALL on the forum that helped with this.
Last edited by Triton170; Jan 24, 2020 at 11:35 AM.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Awwll you lucky dog. That's the Intake I wanted. Did you get a two for price of one deal?
That's a badass Intake. Should feel a little more ommmpp with that set-up too.
That's a badass Intake. Should feel a little more ommmpp with that set-up too.
Last edited by HeadsU.P.; Jan 24, 2020 at 01:18 PM.