75 Corvette Purchase
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There's no good coil on the engine so ill start at the low end see how ot runs.
I've got a parts list on my summit account for many of these fixes. Picked up a cheep set of duralast plug wires at auto zone just to fire the engine back up after nee plugs to see if problems are reduced.
Still working the leakdown test will finish shortly.
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Completed the leakdown test. All cylinders less than 10% at 75 PSI. Should I retest at 100PSI?
Installed new plugs gapped at 0.045" and new plug wires.
Started right up but still smokes and burns oil. Went on a 5mile drive runs much better much smoother. When I got back still could smell burning oil.
Could it be the rings were not clocked 180 from each other? Any suggestions?
Also during leakdown test, I feel like the rockers are looser than I remember the should be. I was able to easily move them side to side. There's no chatter but I thought there should be some friction on the push rods and rockers.
Installed new plugs gapped at 0.045" and new plug wires.
Started right up but still smokes and burns oil. Went on a 5mile drive runs much better much smoother. When I got back still could smell burning oil.
Could it be the rings were not clocked 180 from each other? Any suggestions?
Also during leakdown test, I feel like the rockers are looser than I remember the should be. I was able to easily move them side to side. There's no chatter but I thought there should be some friction on the push rods and rockers.
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Okay, I just woke up and something occurred to me. There was this odd greenish silver goo on some of the push rods under the valve cover. At first I thought that's odd and wiped ot off. Well kinda scrapped it off with my finger.
Leakdown test was good, oil leaking down the sides and back of the engine and smoke on one side of the engine exhaust.
I bet they used gasket maker on the intake manifold or there's a bad intake gasket that was patched with gasket maker and oil is being sucked in the intake.
I'll order a new set of intake gaskets, pop the intake clean every thing and reinstall.
Any thoughts?
Any suggestions on intake manifold gaskets?
Leakdown test was good, oil leaking down the sides and back of the engine and smoke on one side of the engine exhaust.
I bet they used gasket maker on the intake manifold or there's a bad intake gasket that was patched with gasket maker and oil is being sucked in the intake.
I'll order a new set of intake gaskets, pop the intake clean every thing and reinstall.
Any thoughts?
Any suggestions on intake manifold gaskets?
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As for gasket maker or sealer, I'm not a fan, I just like to do it right but given the age of the engine its probably almost required if the surfaces were machined or are pitted or the intake is somehow warped.
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Thank you, I will definitely be looking for oily intake ports.
As for gasket maker or sealer, I'm not a fan, I just like to do it right but given the age of the engine its probably almost required if the surfaces were machined or are pitted or the intake is somehow warped.
As for gasket maker or sealer, I'm not a fan, I just like to do it right but given the age of the engine its probably almost required if the surfaces were machined or are pitted or the intake is somehow warped.
Coolant leaking into bolts, possibly the oil too.
The gaskets are wet all the way to the intake port.
If you look close, you can see a puddle of oil behind the valve. This engine had not run in a week. Which means it leaked in from above.
Well I'm a bit frustrated but not surprised. The top end on the motor needs a complete rebuild. Valve seals are leaking. The gasket surfaces are pitted. The heads do not look rebuild and if there were someone painted the interior parts and the paint is all pealing off and mixing with the oil.
The intake gasket surfaces are pitted. Just old aluminum and corrosion.
Of this engine was rebuilt it wasn't done professionally. Or maybe on a bottom end rebuild. Oh, the intake was not torqued, the bolts were snug but not tight like the should have been.
I'm not sure I want to risk $1,500 in heads, intake, carb and other top end parts only to find the bottom end has issues too.
Gonna swap and get vortek intake and carb setup. I will take this engine to a shop and see about a new life for her.
Any thoughts?
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Coolant leaking into bolts, possibly the oil too.
The gaskets are wet all the way to the intake port
If you look close, you can see a puddle of oil behind the valve. This engine had not run in a week. Which means it leaked in from above.
Well I'm a bit frustrated but not surprised. The top end on the motor needs a complete rebuild. Valve seals are leaking. The gasket surfaces are pitted. The heads do not look rebuild and if there were someone painted the interior parts and the paint is all pealing off and mixing with the oil.
The intake gasket surfaces are pitted. Just old aluminum and corrosion.
Of this engine was rebuilt it wasn't done professionally. Or maybe on a bottom end rebuild. Oh, the intake was not torqued, the bolts were snug but not tight like the should have been.
I'm not sure I want to risk $1,500 in heads, intake, carb and other top end parts only to find the bottom end has issues too.
Gonna swap and get vortek intake and carb setup. I will take this engine to a shop and see about a new life for her.
Any thoughts?
The gaskets are wet all the way to the intake port
If you look close, you can see a puddle of oil behind the valve. This engine had not run in a week. Which means it leaked in from above.
Well I'm a bit frustrated but not surprised. The top end on the motor needs a complete rebuild. Valve seals are leaking. The gasket surfaces are pitted. The heads do not look rebuild and if there were someone painted the interior parts and the paint is all pealing off and mixing with the oil.
The intake gasket surfaces are pitted. Just old aluminum and corrosion.
Of this engine was rebuilt it wasn't done professionally. Or maybe on a bottom end rebuild. Oh, the intake was not torqued, the bolts were snug but not tight like the should have been.
I'm not sure I want to risk $1,500 in heads, intake, carb and other top end parts only to find the bottom end has issues too.
Gonna swap and get vortek intake and carb setup. I will take this engine to a shop and see about a new life for her.
Any thoughts?
There are lots of ways to get that car back on the road, but I would absolutely pull that engine and replace it.
And before you pay a bunch of money for a period-correct SBC, consider a cheap LS swap instead. It might cost the same as just an EFI conversion, and no coolant flows through the intake!
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Used permatex tacky gaskets sealer so hopefully no issues here again.
just trying to keep her running.
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Pulled the plugs again and 1, 3 and 5 were clean, 7 covered in oil. Didn't get to the other side yet.
Pulled the valve springs on cylinder 7. The intake has brand new seal but missing the o-ring at the retainer clips.
The exhaust valve stem had no umbrella seal and no o-ring. I got a set of Fel-Pro umbrella seals and o-rings. Will take pictures tomorrow and complete the rebuild on yhe valve stem seals tomorrow.
What baffels me is why would someone buy expensive intake seals and not even bother to rebuild the exhaust side. the seals on the intake side are not the cheap umbrella these are quality seals the $5 ones.
Also the universe spoke and by sheer luck someone near by was selling an edelbrock carb intake for vortec heads 2116, perfect fit for my backup engine. New never opened still in the original bag. So at this point EFI will be on the back shelf.
Pulled the valve springs on cylinder 7. The intake has brand new seal but missing the o-ring at the retainer clips.
The exhaust valve stem had no umbrella seal and no o-ring. I got a set of Fel-Pro umbrella seals and o-rings. Will take pictures tomorrow and complete the rebuild on yhe valve stem seals tomorrow.
What baffels me is why would someone buy expensive intake seals and not even bother to rebuild the exhaust side. the seals on the intake side are not the cheap umbrella these are quality seals the $5 ones.
Also the universe spoke and by sheer luck someone near by was selling an edelbrock carb intake for vortec heads 2116, perfect fit for my backup engine. New never opened still in the original bag. So at this point EFI will be on the back shelf.
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By "Edelbrock carb intake", do you mean 4 equal sized holes, or "square bore"?
If that is the case, there are a few Holley carbs that seem acceptable to folks on this Forum. Do a search, or perhaps someone will suggest one.
If that is the case, there are a few Holley carbs that seem acceptable to folks on this Forum. Do a search, or perhaps someone will suggest one.
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This one, not the square bore.
As for carbs, I haven't made a decision yet. Been reading Holly v.s. Edelbrock. Since I'm more of a street driver and not really ever planning on racing i think Edelbrock would be fine. I'd perfer not to get into another massive discussion on this topic since there are plenty out there but if anyone want to share picks and experience with the two that's fine.
Probably going to get a 600 or 650cfm. Either one would be fine in my use case. If I get a roller cam and one that will top 7k rpm 650 would be better. I'm not sure I want to top 7k RPM though that's just asking for trouble.
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oh my bad, I just looked up on Edelbrocks site and it does accept square bore. I have a quadrajet already, which is why I jumped on this intake. But if something comes up in the 4150-style square bore that's a good deal I'll probably jump on that.
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yes that is a both-types intake. and both work equally well. what carb does the car have now? a guy named Lars is the q-jet guru. and a well set up q-jet is a very nice carb. and a 750 or 780 with smaller primaries. judging by the intake on there it is a q-jet. and the old gaskets look oily. engine vacuum may have been sucking oil out of the lifter valley.
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yes that is a both-types intake. and both work equally well. what carb does the car have now? a guy named Lars is the q-jet guru. and a well set up q-jet is a very nice carb. and a 750 or 780 with smaller primaries. judging by the intake on there it is a q-jet. and the old gaskets look oily. engine vacuum may have been sucking oil out of the lifter valley.
Missing needle on idle mixture? This is looking from front driver side. Screw in the middle is the idle stop. Hole to the right and slightly below should be a mixture screw.
The idle never drops below 1200 RPMs.
You are correct, there is an oily residue but given there's only 4 vacuum lines, PCV, brake booster and Headlights/something in the cab and timing advance im nit sure where it came from. PCV hose is clean. Could just be old gas residue. I like the QJets they are very nice robust carb. However, since the engine in building is a performance engine I was hoping for something with a bit more.
Definitely oil was being sucked by the intake gaskets. No doubt given the intake bolts were not even close to torque spec.
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Exhause valve guides were replaced. But it looks like the original guides broke near the top leaving one the valve guide seal. Is this okay? Or do i run the risk of bending a valve stem or worse? 1,3,5 plugs were not fouled but still considering pulling the springs to inspect.
Installed a new umbrella have little doublet it will improve oil burn.
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#2 valves
#2 plug oil fouled, 4,6, & 8 are okay.
in the picture you can see the seal is split along the left side.
So these heads are probably toast. I dont know that they can be resleeved.
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the oil seals are almost not needed on exhaust valves. when worn, exhaust pressure blows up them. they don't suck crankcase fumes in like the intakes do. many racers and boat people do not even run seals on the exhaust valves. how much side-side wiggle on those valves?
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the oil seals are almost not needed on exhaust valves. when worn, exhaust pressure blows up them. they don't suck crankcase fumes in like the intakes do. many racers and boat people do not even run seals on the exhaust valves. how much side-side wiggle on those valves?
What really bothers me is the cast iron portion on the stem guides are broken surfaces not machined down. So either they broke after beings installed and run or broke when installing. This also means many of the seals won't fit right unless I can find some undersized seals. I could slip the seals off by hand on both the #2 and #7 intake. So it's probably just sucking oil in from the heads.
Blowing hot exhaust in to the heads is probably causing all the burnt oil on the springs. #7 is especially bad. Plus doesn't that lead to carbon building up on the stem and stuck valves that end up hitting the pistons.
Sorry, I'm a bit OCD with these things and perfer to keep everything running as it should. Would hate to be out driving only to be stuck on the side of the road.