Removed intake, Have CONCERNS please look
Le Mans Master
Joined: Nov 1999
Posts: 5,768
Likes: 3
From: San Diego CA
Those are not vacuum ports on your intake, they are hot air ports for the hot air choke - as mentioned by others, just block it off if you use something other than the original hot air choke
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Question on Distrb. When I replace it there is only one gasket. I thought there was also a O-Ring on the shaft. But when I pulled mine, there was none, and no place for one. Is this correct?
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
I'm at work now, and it just dawned on me that I made a BIG noobie mistake! I marked the location of the Distrb. on the fire wall and on it. BUT DID NOT make the second mark for the inside cap!!!!!!! My motor is not at DTC. And I have the valve covers on. The only insight I have to figure out where the engine is at is looking at the lifters in the gully. I do not remember moving the cap once I pulled it and set it on the table. I know it can only go in two ways. Due to the oil pump slot. So when I replace it I have a 50/50 chance of getting it correct, or 180 degrees off. Can you do damage to an engine if you have it 180 off and try to start it? Boy do I feel like an idiot!!!!!
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
You can use an thin oring on top of the intake instead of the little round gasket.
With the intake off, just make sure the lifters on #1 are in the lowest position and even (you can tell by the tarnish marks) and the balancer is close to 0.
Don't worry about the oil shaft, the dist will sink when you bump the engine.
With a new manifold, DO check that the dist will seat all the way down first without a gasket and not bind on the oil shaft.
If you have a spare plug, here is a really simple tool to make that prevents the need to remove valve cover etc to find #1. Easiest way I have ever found.
With the intake off, just make sure the lifters on #1 are in the lowest position and even (you can tell by the tarnish marks) and the balancer is close to 0.
Don't worry about the oil shaft, the dist will sink when you bump the engine.
With a new manifold, DO check that the dist will seat all the way down first without a gasket and not bind on the oil shaft.
If you have a spare plug, here is a really simple tool to make that prevents the need to remove valve cover etc to find #1. Easiest way I have ever found.
Try this way.
Looking at the front of the engine from the front of the car the balancer turns clockwise. The distributer turns clockwise looking down at it.
Almost foolproof method:
Get an old sparkplug that fits the engine.
Knock the guts out of it with a punch and hammer.
Stretch a balloon over the sparkplug leaving the threads exposed. (Balloons from Dollar Store)
Hand tighten the balloon/sparkplug into the #1 hole.
Disconnect power to distributor or make sure ignition is off.
Slowly turn over engine in clockwise direction with a socket and ratchet on the harmonic balancer center bolt.
Balloon will fill with air when approaching #1 firing position. It won't stay full so you have to watch it closely.
The mark on the balancer will be at approx 6 o'clock, so forget about the ballon and continue turning the engine over.
Continue to turn engine until the mark on balancer reaches the 10° BTDC mark.
This is close to the initial timed firing position.
Install dist with the rotor pointing approximatedly at the #2 terminal on the cap. (Just before #1 on cap)
Push down slowly and you will feel the gears mesh and the rotor will move toward the #1 position.
If it is going to go past #1, then slowly pull up on the distributer until you feel the gears "unmesh". then turn the rotor more towards the #2 direction with slight pressure down until you feel you have moved over 1 more tooth.
Then push down as far as it will go again to see if it is close to lining up with #1 terminal.
If the distributer housing base where you clamp it tight has a gap between it and the intake manifold, then the oil shaft has not lined up.
If this is the case, then the rotor should be between the #1 and #2 terminals on the cap.
Then just push down lightly on the distributer housing (watch out for spinning rotor) while someone cranks the starter over, and it will drop in place and the timing will be correct to fire up.
It may sound a little confusing, but try it and it's pretty simple and is is the easiest way I have found.
To check it, do the balloon thing again with the distributor now being fully seated on the intake. Turn the distributer housing until the rotor leading edge meets the #1 cap terminal. If the housing is oriented properly as in the first pic then you will have ample room for the vacumn advance can to turn the distributer for timing. Now clamp the distributor fairly tight and use you timing lite to time engine to your specs.
Use one of the papers in a sticky at top.
Looking at the front of the engine from the front of the car the balancer turns clockwise. The distributer turns clockwise looking down at it.
Almost foolproof method:
Get an old sparkplug that fits the engine.
Knock the guts out of it with a punch and hammer.
Stretch a balloon over the sparkplug leaving the threads exposed. (Balloons from Dollar Store)
Hand tighten the balloon/sparkplug into the #1 hole.
Disconnect power to distributor or make sure ignition is off.
Slowly turn over engine in clockwise direction with a socket and ratchet on the harmonic balancer center bolt.
Balloon will fill with air when approaching #1 firing position. It won't stay full so you have to watch it closely.
The mark on the balancer will be at approx 6 o'clock, so forget about the ballon and continue turning the engine over.
Continue to turn engine until the mark on balancer reaches the 10° BTDC mark.
This is close to the initial timed firing position.
Install dist with the rotor pointing approximatedly at the #2 terminal on the cap. (Just before #1 on cap)
Push down slowly and you will feel the gears mesh and the rotor will move toward the #1 position.
If it is going to go past #1, then slowly pull up on the distributer until you feel the gears "unmesh". then turn the rotor more towards the #2 direction with slight pressure down until you feel you have moved over 1 more tooth.
Then push down as far as it will go again to see if it is close to lining up with #1 terminal.
If the distributer housing base where you clamp it tight has a gap between it and the intake manifold, then the oil shaft has not lined up.
If this is the case, then the rotor should be between the #1 and #2 terminals on the cap.
Then just push down lightly on the distributer housing (watch out for spinning rotor) while someone cranks the starter over, and it will drop in place and the timing will be correct to fire up.
It may sound a little confusing, but try it and it's pretty simple and is is the easiest way I have found.
To check it, do the balloon thing again with the distributor now being fully seated on the intake. Turn the distributer housing until the rotor leading edge meets the #1 cap terminal. If the housing is oriented properly as in the first pic then you will have ample room for the vacumn advance can to turn the distributer for timing. Now clamp the distributor fairly tight and use you timing lite to time engine to your specs.
Use one of the papers in a sticky at top.
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Michael S. Palmer
Safety Car
Joined: Oct 2000
Posts: 3,593
Likes: 103
From: Southern Indiana
Drifting
Joined: Jul 2002
Posts: 1,944
Likes: 20
From: The only Corvettes in Highett Victoria
Exhaust crossover.
daanbc,
Welcome to the Forum. Just in case you don't know what the exhaust crossover is for, I'll tell you. When these cars were designed, they had to be able to be sold in Alaska as well as Florida, and they needed a way to warm up quickly to avoid engine stalling due to the cold.
So they designed the EFE - Early Fuel Evaporation - which comprised of a shut-off valve in the right hand exhaust manifold. This was held closed by spring pressure but was opened by a vacuum signal from a thermal vacuum switch on the thermostat housing, from memory.
When closed, all the exhaust from the right bank was blocked from flowing into the engine pipe and out the exhaust by this shut-off valve. The exhaust gases then only had one route - back up the manifold, into the head and out through the crossover port in the middle of the head.
From there it went through the bottom of the inlet manifold and gave up some of its heat to the underside of the inlet manifold plenum, heating the cold air/fuel mixture contained within and helping to keep the mixture atomised for good combustion once it reached the cylinders.
The right hand exhaust gases then entered the left hand head through the central crossover port and out through the two centre exhaust ports on the left head. So, when cold, the two centre exhaust ports on the left head were flowing exhaust gases from SIX!!! cylinders into the exhaust pipe, and converter if fitted.
In Florida, however, there is no need for this EFE system and as noonie correctly said, just disconnect the choke and the shut-off valve if still fitted. Make sure you lock it in the OPEN position!! And make sure that you block off the central crossover port before you fit the manifold. If it was me, I'd have a solid plate or plug TIG welded just inside each port and just use normal gaskets.
Funnily enough, if you had left the gunk that you found in the cylinder head crossover ports alone, you would have achieved basically the same result, but you've opened them up and must now stop the hot gases from flowing under the carburettor.
Hope this helps.
Regards from Down Under.
aussiejohn
Welcome to the Forum. Just in case you don't know what the exhaust crossover is for, I'll tell you. When these cars were designed, they had to be able to be sold in Alaska as well as Florida, and they needed a way to warm up quickly to avoid engine stalling due to the cold.
So they designed the EFE - Early Fuel Evaporation - which comprised of a shut-off valve in the right hand exhaust manifold. This was held closed by spring pressure but was opened by a vacuum signal from a thermal vacuum switch on the thermostat housing, from memory.
When closed, all the exhaust from the right bank was blocked from flowing into the engine pipe and out the exhaust by this shut-off valve. The exhaust gases then only had one route - back up the manifold, into the head and out through the crossover port in the middle of the head.
From there it went through the bottom of the inlet manifold and gave up some of its heat to the underside of the inlet manifold plenum, heating the cold air/fuel mixture contained within and helping to keep the mixture atomised for good combustion once it reached the cylinders.
The right hand exhaust gases then entered the left hand head through the central crossover port and out through the two centre exhaust ports on the left head. So, when cold, the two centre exhaust ports on the left head were flowing exhaust gases from SIX!!! cylinders into the exhaust pipe, and converter if fitted.
In Florida, however, there is no need for this EFE system and as noonie correctly said, just disconnect the choke and the shut-off valve if still fitted. Make sure you lock it in the OPEN position!! And make sure that you block off the central crossover port before you fit the manifold. If it was me, I'd have a solid plate or plug TIG welded just inside each port and just use normal gaskets.
Funnily enough, if you had left the gunk that you found in the cylinder head crossover ports alone, you would have achieved basically the same result, but you've opened them up and must now stop the hot gases from flowing under the carburettor.
Hope this helps.
Regards from Down Under.
aussiejohn
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
[QUOTE=aussiejohn;1578842239]daanbc,
Welcome to the Forum. Just in case you don't know what the exhaust crossover is for, I'll tell you. When these cars were designed, they had to be able to be sold in Alaska as well as Florida, and they needed a way to warm up quickly to avoid engine stalling due to the cold.
THANK YOU VERY MUCH!!!
Welcome to the Forum. Just in case you don't know what the exhaust crossover is for, I'll tell you. When these cars were designed, they had to be able to be sold in Alaska as well as Florida, and they needed a way to warm up quickly to avoid engine stalling due to the cold.
THANK YOU VERY MUCH!!!
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Drifting
Joined: Jul 2002
Posts: 1,944
Likes: 20
From: The only Corvettes in Highett Victoria
[QUOTE=daanbc;1578842326]
You're most welcome. So tell me, what exhaust system do you currently have on your car?
Regards from Down Under.
aussiejohn
daanbc,
Welcome to the Forum. Just in case you don't know what the exhaust crossover is for, I'll tell you. When these cars were designed, they had to be able to be sold in Alaska as well as Florida, and they needed a way to warm up quickly to avoid engine stalling due to the cold.
THANK YOU VERY MUCH!!!
Welcome to the Forum. Just in case you don't know what the exhaust crossover is for, I'll tell you. When these cars were designed, they had to be able to be sold in Alaska as well as Florida, and they needed a way to warm up quickly to avoid engine stalling due to the cold.
THANK YOU VERY MUCH!!!
Regards from Down Under.
aussiejohn
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
Hey Dave. When I get mine back running, I am going to lower the front suspension as the front of the car sits too high. After you remove all of that weight you might need to do the same thing.
It is always something. mike...
It is always something. mike...
Thread Starter
Melting Slicks
Joined: Aug 2010
Posts: 2,487
Likes: 10
From: Palm Beach Florida
St. Jude Donor '12
Burning Brakes
Joined: Apr 2007
Posts: 1,039
Likes: 62
From: Kona Hawaii
Tips
A couple of tips to help with the manifold install.Clean,clean ,clean all mating surfaces with lacquer thinner till the rag shows no oil residue including the new manifold.Test fit manifold and check how high your bead of sealant needs to be for the block front and back.I used a 2 1/2 in dia wooden dowel in dist hole to help align the manifold on block.Clean threads on cylinder heads.New intake bolts with small heads and sealant on the threads to avoid oil seepage. I put a thin coat of sealant on each intake port on the cylinder head side, not the intake side of the gasket.A little heavier coat on water jackets.Torque to specs and in sequence per instructions. If you pay attention to detail hopefully you will just need to do this once and have no leaks.
Another thing to consider changing while you have your intake off is the oil pump intermediate shaft.The stock ones have a plastic coupler that could break with age.I replaced mine with a solid shaft from Milodon.My oil pan was smashed so I replaced it along with new pump and new shaft.Not sure if you can replace the shaft from the the dist hole,maybe someone that has done it this way can confirm it is possible.Good luck and no leaks.....Aloha's
Another thing to consider changing while you have your intake off is the oil pump intermediate shaft.The stock ones have a plastic coupler that could break with age.I replaced mine with a solid shaft from Milodon.My oil pan was smashed so I replaced it along with new pump and new shaft.Not sure if you can replace the shaft from the the dist hole,maybe someone that has done it this way can confirm it is possible.Good luck and no leaks.....Aloha's
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
An other good reason to block the crossover exhaust port is to keep the heat away from the carb.
This specially after engine shutdown or even in stop & go driving situations, where the carb fuel can start cooking also due to the very hot manifold area where the carb sits on.
We are not driving our old Vettes in bead or freezing weather anymore, so no requirement to heat up the carb. This crossover heating right now is making more bad as good and blocking it off is a step into the right direction.
And yes, changing the manifold for weight reasons is already good enough. This concrete ( cast iron ) manifolds are just too heavy.
Even worse on a BB . It's a cheap way to save plenty of weight.
Next step is alu heads.
Rgds. Günther
An other good reason to block the crossover exhaust port is to keep the heat away from the carb.
This specially after engine shutdown or even in stop & go driving situations, where the carb fuel can start cooking also due to the very hot manifold area where the carb sits on.
We are not driving our old Vettes in bead or freezing weather anymore, so no requirement to heat up the carb. This crossover heating right now is making more bad as good and blocking it off is a step into the right direction.
And yes, changing the manifold for weight reasons is already good enough. This concrete ( cast iron ) manifolds are just too heavy.
Even worse on a BB . It's a cheap way to save plenty of weight.
Next step is alu heads.
Rgds. Günther