Carburetor question for 66 C-10 with 283

[AslanRules]

Originally Posted by markeb01

If it were mine, I wouldn't replace the carb. It would be a lot cheaper to simply add a manual choke kit, which is a simple bolt on:

http://www.jegs.com/i/Holley/510/45-...FSCjiQodkXSuPQ

Thanks for the link.

What you have is known to fit, and probably works fine, but you won't be able to tell until the manifold leaks are fixed. Unless you're after performance potential I'd stick with the stock cast iron manifold. One nice feature is they almost never warp, which is a risk with used aluminum manifolds.

My son-in-law is pushing me towards Edelbrock.....and you have stated previously that they are easier to maintain and rebuild, especially for a rook. And I can sell the Holley to offset the new purchase. By performance, I assume that you mean acceleration, etc. I'm not interested in racing, but it's nice to get up and go occasionally. But not at the expense of mpg. I'll probably keep the original manifold.....but just for yucks, would I realize $200 worth of difference with a NEW Edelbrock manifold to go with my NEW Edelbrock 1405?

As for the HEI, in order to have a baseline it would be a good idea to replace the cap and rotor, or at least inspect the contacts for pitting or corrosion. There really isn't any maintenance required unless the area of the centrifugal weights gets really cruddy. You might also want to check the condition of the vacuum advance. It can be tested easily with a timing light. Disconnect the vacuum line to it and plug the line. Idle the engine and check the timing. Connect a hose from a full vacuum manifold vacuum source (or a vacuum pump). If the vacuum advance is working, the timing will advance.

Looks like a timing light and vaccum gauge are in my future. Wish I had kept my Penske stuff from years ago.

Rookie question: is the HEI cap and rotor one-size-fits-all, or do I need to get a part number from the existing dizzy?

The money I didn't spend on a carburetor or manifold, I'd invest in a new gas tank. If the repair wasn't done any better than the manifold, the tank could be in worse shape than if it hadn't been "fixed" in the first place. Debris in the gas tank can lead to endless problems that can be hard to diagnose. If you do replace the tank, replace the filter again in case anything was disturbed during the exchange.

Yeah.....I was afraid of that.

I'm an old guy, and have observed that competency isn't age related. I've met guys much older than me, and others half my age that know more than I'll ever learn.

By all means.........I just didn't want to offend anyone by continuing to call the previous owner "the old guy".

Thanks,

Randy

[geezer#99]

You know what they say. Old guys rule!!! Or is that old guys drool. Anywho.
Keep the intake. You might see 10 hp diffy with a new one. Edelbrock 500cfm carb would be good. Change a couple more things. Get rid of the hose for the fuel line. Fire hazard potential. New spark plug wires. You can get a new HEI from Skip White instead of rebuilding yours. Probably cheaper too.
Throttle return spring needs attention. Hooked on where it is is not good. Put it in the hole on the arm. I always run 2 springs. 1 strong and 1 lighter. In case the strong one breaks. Some of the smaller lighter ones will fit inside the bigger stronger one too.
Have fun. Take some more pics as you progress and keep asking those questions. We're happy to help out if we can.

[markeb01]

The only real advantage in replacing the manifold is it will look new, match the appearance of the carburetor, and eliminate the need to clean the old one. The limiting factor in performance will remain the heads, valves, camshaft and exhaust. If it makes you feel better or happy installing a new manifold, go for it. I’ve certainly bought new stuff just because I wanted it.

If you’re going with the Edelbrock you might be happier with the 1404 (500 cfm model) instead of the 1405 (600 cfm), unless you intend to replace the engine with a 350 someday.

http://www.jegs.com/i/Edelbrock/350/...0002/-1?CT=999
http://www.jegs.com/pdfs/350carbchart.pdf

Edelbrock recommends the 500 cfm size for engines between 225 and 327 cubic inches. They recommend the 600 version for engines between 302 – 400+. A smaller carb will provide an increased signal improving part throttle driveability.

The distributor cap is common to a bunch of applications from 1974 -1987. Just ask for a cap for a 1975-86 Chevy C10. Here’s a cross reference listing from O’Reilly auto parts to show how many places this was used. Just click on the compatibility tab in the middle.

http://www.oreillyauto.com/site/c/de...0413&ppt=C0334

On the subject of the valve cover breathers - when the 283 was first released it didn’t have a smog valve. For crankcase ventilation it used a breather cap on the oil fill tube, and a road draft tube on the back of the block behind the intake manifold. In theory, driving the vehicle over 25 miles per hour would create a “draft” or negative pressure over the bottom of the tube caused by air movement across the opening. Crankcase fumes were drawn out the bottom of the tube, and replaced by fresh air entering the breather cap. It was a less than efficient design being open to the atmosphere, and if the vehicle never went fast enough to create a draft (like a milk delivery truck), tremendous sludge would build up inside the engine.

Factory PCV setups don’t have a breather open to the atmosphere, air is normally provided through hoses or ducting connected to the air cleaner. In a non stock application you ideally want the PCV valve on one side or one end of the engine, and the fresh air source on the other side or end to maximize ventilation. Although not as optimum as having a breather on the opposite valve cover, your engine should be adequately ventilated the way it is set up with the fresh air in the front through the oil fill breather cap. Just don’t replace the breather with a sealed cap. What doesn’t work well is using an oil fill tube with the smog valve screwed into the tube, mounting a breather cap on top. This will have almost no effect on evacuating the crankcase, since fresh air will be drawn through the PCV valve straight from the breather cap instead.

Your valve cover may also be a potential source of oil leakage where the smog valve was installed. 283 covers were never designed to have an opening. Early models used an adapter that replaced the road draft tube, adding a stub for a hose which connected to an inline PCV valve. Either the early adapter or later model valve covers designed for a smog grommet would provide more leak free service.

[AslanRules]

Originally Posted by geezer#99

You know what they say. Old guys rule!!! Or is that old guys drool. Anywho.
Keep the intake. You might see 10 hp diffy with a new one. Edelbrock 500cfm carb would be good. Change a couple more things. Get rid of the hose for the fuel line. Fire hazard potential. New spark plug wires. You can get a new HEI from Skip White instead of rebuilding yours. Probably cheaper too.
Throttle return spring needs attention. Hooked on where it is is not good. Put it in the hole on the arm. I always run 2 springs. 1 strong and 1 lighter. In case the strong one breaks. Some of the smaller lighter ones will fit inside the bigger stronger one too.
Have fun. Take some more pics as you progress and keep asking those questions. We're happy to help out if we can.

Geezer....thanks for the comments.

I rarely drool anymore......mostly when I sleep.

500 cfm, eh? Sounds good. That would be a #1404.....I can get a rebuilt one directly from Edelbrock for $315, and maybe cheaper elsewhere.

I had already decided that I needed new spark plug wires....some of them look a little melted. I'm not sure if "T.O.G." bought the HEI new or used. I have all of his receipts somewhere and I can look it up.

Fuel hose? You mean the one from the fuel filter to the carb? What should I replace it with?

Throttle return spring: it's not supposed to hook on to that little flange on the oil filling spout? Or are you referring to the proximal attachement on the carb?

Thanks,

Randy

[geezer#99]

Hey young fella. LOL!!!
Throttle return spring hooked on the carb linkage is iffy.
Fuel hose. Hard line. 5/16th tube. Napa has them pre-built in many lengths.
Edelbrock carb. 1404 sounds right. Try ebay or Summit Racing or Jeg's. Cheaper by about 80 bucks.
Have you ever pulled the top off an engine before? If not we're here to walk you through it. Glad to help.

[AslanRules]

Originally Posted by geezer#99

Hey young fella. LOL!!!
Throttle return spring hooked on the carb linkage is iffy.
Fuel hose. Hard line. 5/16th tube. Napa has them pre-built in many lengths.
Edelbrock carb. 1404 sounds right. Try ebay or Summit Racing or Jeg's. Cheaper by about 80 bucks.
Have you ever pulled the top off an engine before? If not we're here to walk you through it. Glad to help.

Hell no, but how hard can it be???? I've got a monkey wrench, a cooler of beer, and lots of band-aids.

Actually, I'm going to need all the help I can get. And my son-in-law will be there......he's done it, but only on a FORD!!!!!!!

[Slow Build]

Originally Posted by AslanRules

......he's done it, but only on a FORD!!!!!!!

Good. That means he will be used to troubleshooting just incase there's a problem.

[Rich 5150 69]

Boy an`t that the truth.....LOL

[Rich 5150 69]

Thats why we do this....

[IMG][/IMG]

[geezer#99]

Randy. Don't forget to take pics. Not for us but references for you when you go to put it back together. Pics work better than the old memory does. Pick up a book on How to rebuild your small block chevy. That'll help alot. Don't cut costs on intake gaskets. Buy good stuff. Fel-Pro is a good one to use. Happy wrenchin'.

[AslanRules]

Originally Posted by markeb01

On the subject of the valve cover breathers - when the 283 was first released it didn’t have a smog valve. For crankcase ventilation it used a breather cap on the oil fill tube, and a road draft tube on the back of the block behind the intake manifold. In theory, driving the vehicle over 25 miles per hour would create a “draft” or negative pressure over the bottom of the tube caused by air movement across the opening. Crankcase fumes were drawn out the bottom of the tube, and replaced by fresh air entering the breather cap. It was a less than efficient design being open to the atmosphere, and if the vehicle never went fast enough to create a draft (like a milk delivery truck), tremendous sludge would build up inside the engine.

Factory PCV setups don’t have a breather open to the atmosphere, air is normally provided through hoses or ducting connected to the air cleaner. In a non stock application you ideally want the PCV valve on one side or one end of the engine, and the fresh air source on the other side or end to maximize ventilation. Although not as optimum as having a breather on the opposite valve cover, your engine should be adequately ventilated the way it is set up with the fresh air in the front through the oil fill breather cap. Just don’t replace the breather with a sealed cap. What doesn’t work well is using an oil fill tube with the smog valve screwed into the tube, mounting a breather cap on top. This will have almost no effect on evacuating the crankcase, since fresh air will be drawn through the PCV valve straight from the breather cap instead.

Your valve cover may also be a potential source of oil leakage where the smog valve was installed. 283 covers were never designed to have an opening. Early models used an adapter that replaced the road draft tube, adding a stub for a hose which connected to an inline PCV valve. Either the early adapter or later model valve covers designed for a smog grommet would provide more leak free service.

Mark,

So what do you recommend for me to do to maximize ventilation, minimize oil leakage, and be easy to accomplish? Please provide links if you have them.

Thanks,

Randy

[markeb01]

Hi Randy if originality isn’t important, the simplest thing would be to add a later model valve cover designed to have smog/breather grommets. Any pre-1987 305/350 cover(s) would work. Just replace the damaged cover with one designed for a smog valve. The existing oil fill breather tube will provide incoming air. If you add later valve covers and want additional ventilation simply install a breather on the other valve cover as well. I’d keep the oil fill tube regardless, because it’s generally easier to add oil to the engine through the tube rather than the valve cover. Stock painted cover(s) from the junkyard will do, or there are numerous inexpensive chrome versions available. Here’s a current example on eBay:

http://cgi.ebay.com/ebaymotors/CHEVY...Q5fAccessories

If you look closely you can see the rims or flanges formed in the covers for the breather or smog grommet (which your 283 cover lacks)

Here’s an example of a push in breather:

http://www.summitracing.com/parts/SUM-G3400/

The cover you have “may” work, but it just has a hole cut in a piece of thin sheet metal to retain the grommet, and it may or may not seal well, and it may eventually cut the lower portion of the grommet off and drop it in the rocker arm area. If it doesn’t leak, the arrangement you have will work fine – air will enter through the breather cap on the oil fill tube and be drawn out through the smog valve. This is the arrangement I have on my engine although the smog connection is hidden on mine. Since appearance was important in my application, and my engine is a 350 (lacking the hole in the block for the road draft tube) here’s a link showing what I did:

http://67-72chevytrucks.com/vboard/s...d.php?t=366853

The other option, if an original appearance is important – obtain a mid 60’s Chevy smog adapter. Post #7 on the attached link shows this adapter. It simply replaces the road draft tube, and even uses the original bolt and washer. An inline PCV valve connects to the hose barb, and the other end connects to the intake manifold or base of the carburetor.

http://www.hotrodders.com/forum/draf...cv-151613.html

I don’t believe this piece is being reproduced, so the only option is to source an original. This arrangement performs similar to what I’m running - air enters through the oil fill tube breather, and is evacuated at the back of the engine block behind the intake manifold instead of the valve cover. This will allow the use of early 283 or 327 sealed valve covers should that be preferred.

I’ve taken the liberty of borrowing a recent photo from Tony Smith showing the adapter installed:

[raycow]

If you can't find an original or repro adaptor for the back of the block, look for a grommet that fits the hole. Then stick a nipple in the grommet and hook your hose to that. You could also put a PCV valve directly into the grommet.

Another way is to get a freeze plug that fits the hole. Then braze a nipple or pipe bushing into the freeze plug and drive it into the block. I have used all of these fixes on different projects over the years, depending on what I could find or had lying around the garage.

Ray

[Rich 5150 69]

Do we know yet if it is an early block....? Randy under your alternator on the block is a pad that wil have a series of numbers letters, see if you can ead these, that will give a better clue as to what we are dealing with..

[AslanRules]

Originally Posted by markeb01

Hi Randy if originality isn’t important, the simplest thing would be to add a later model valve cover designed to have smog/breather grommets. Any pre-1987 305/350 cover(s) would work. Just replace the damaged cover with one designed for a smog valve. The existing oil fill breather tube will provide incoming air. If you add later valve covers and want additional ventilation simply install a breather on the other valve cover as well. I’d keep the oil fill tube regardless, because it’s generally easier to add oil to the engine through the tube rather than the valve cover. Stock painted cover(s) from the junkyard will do, or there are numerous inexpensive chrome versions available. Here’s a current example on eBay:

http://cgi.ebay.com/ebaymotors/CHEVY...Q5fAccessories

If you look closely you can see the rims or flanges formed in the covers for the breather or smog grommet (which your 283 cover lacks)

Here’s an example of a push in breather:

http://www.summitracing.com/parts/SUM-G3400/

The cover you have “may” work, but it just has a hole cut in a piece of thin sheet metal to retain the grommet, and it may or may not seal well, and it may eventually cut the lower portion of the grommet off and drop it in the rocker arm area. If it doesn’t leak, the arrangement you have will work fine – air will enter through the breather cap on the oil fill tube and be drawn out through the smog valve. This is the arrangement I have on my engine although the smog connection is hidden on mine. Since appearance was important in my application, and my engine is a 350 (lacking the hole in the block for the road draft tube) here’s a link showing what I did:

http://67-72chevytrucks.com/vboard/s...d.php?t=366853

The other option, if an original appearance is important – obtain a mid 60’s Chevy smog adapter. Post #7 on the attached link shows this adapter. It simply replaces the road draft tube, and even uses the original bolt and washer. An inline PCV valve connects to the hose barb, and the other end connects to the intake manifold or base of the carburetor.

http://www.hotrodders.com/forum/draf...cv-151613.html

I don’t believe this piece is being reproduced, so the only option is to source an original. This arrangement performs similar to what I’m running - air enters through the oil fill tube breather, and is evacuated at the back of the engine block behind the intake manifold instead of the valve cover. This will allow the use of early 283 or 327 sealed valve covers should that be preferred.

I’ve taken the liberty of borrowing a recent photo from Tony Smith showing the adapter installed:

Mark,

Thanks for an awesome post and explanation. I've spent the better part of the day researching the links and topics that you've discussed. I think I've got a good understanding of breathers, pcv's, etc., now.

I looked under my hood today to see if I could find the breather hole at the rear of the block, but I couldn't see it. I looked from all angles, including crawling underneath, but couldn't visualize the area. Prior to that, I had hoped to find an adapter and mount the in-line pcv valve for ventilation, using the oil filler cap as the air intake. Then I was going to buy a replacement right valve cover WITHOUT a hole drilled in it, thus returning my engine to a more vintage look. BUT......since I can't even SEE the hole, I figure I wouldn't be able to mount the adapter anyway. So I'm going to just leave the ventilation as it is. I DID find a source for the adapter HERE (I think). I'm sure other sites carry them as well.

So.....here's my current plan. See if it sounds good to you and if I'm missing anything.

1) Remove carb and intake manifold, clean it, and put a new gasket and silicone sealer under it.
2) Consider replacing stock intake with Edelbrock intake manifold. It might look cool to have a matching carb and intake, and oil filler as well.
3) Replace my carb with an Edelbrock 4-bbl (#1404) with manual choke. (Will sell the old Holley carb and adapter).
4) If I keep my stock intake, I'll need an adapter for the Edelbrock.
5) Check and replace as necessary:
a) Distributor cap and rotor....maybe a BLUE one.
b) Spark plugs: AC Delco R45TS
c) Spark plug wires: BLUE.....or maybe RED.

BUT.....before I do all of that, I'm going to replace my gas tank, cover, and fuel filter. (BTW.....do I need to remove the seat in order to remove the gas tank?)

So.....whaddya think? Any opinions or advice is appreciated.

Thanks,

Randy

[AslanRules]

Originally Posted by raycow

If you can't find an original or repro adaptor for the back of the block, look for a grommet that fits the hole. Then stick a nipple in the grommet and hook your hose to that. You could also put a PCV valve directly into the grommet.

Another way is to get a freeze plug that fits the hole. Then braze a nipple or pipe bushing into the freeze plug and drive it into the block. I have used all of these fixes on different projects over the years, depending on what I could find or had lying around the garage.

Ray

See post above.

Thanks,

Randy

[AslanRules]

Originally Posted by Rich 5150 69

Randy before you go any further, you have a four brrl intake with a holley 600 4160 carb, HEI dizzy, but you have a terrible intake manifold leak all the way around, you`ll needto pull the entire manifold, clean the surfaces well, with new gaskets, a light coating of silicone on the intake bolt threads to seal everythng up.

Gotta couple more questions, boys:

1) Which sealant do you recommend?

http://www.summitracing.com/parts/LCT-37460/

http://www.summitracing.com/parts/LCT-37467/

2) How do you machine a boss in the intake? Let me be more specific. I can buy the Edelbrock 2101 Intake for $128, and then add the oil filler for another $13, for a total of $141. But then I have to machine the oil filler boss......do you just grab a sawzall and go to work? ;-)

The other option is to buy the 2703 Intake which includes the oil filler AND is already machined......I think. The price is $53 more. It has slightly better performance characteristics also.

So.......is it worth $53 to have a "pre-machined" boss, or do I save $53 and machine it myself?

Thanks,

Randy

[geezer#99]

I use black form-a-gasket or gasket maker. Good for higher temps.
Get the regular 2101 intake and go to the local wrecking yard and get a pair of newer valve covers with the baffle for the pcv on one side and a twist in cap for the other side that you could put a twist in breather on.

[Rich 5150 69]

Ok Randy no updates, the suspense is intense......

[Slow Build]

Here is what it looks like from the top. Since I have the Distributor out I have a few things back there to do before the HEI goes in (change the angle of oil pressure sending unit, ad a PVC).

[markeb01]

Hi Randy, if you really want to retain the early appearance and convenience of the oil fill tube, I’d suggest spend the extra money and buy the manifold with the oil fill tube already machined in. I was running an Edelbrock 7101 Performer RPM manifold that already had the oil fill tube boss in place. Since my son is a machinist he bored the hole in my manifold using a mill. The setup took a bit of time to get the angles correct. I you have to pay someone it might end up costing more than $53. I’ve read different accounts on the internet where some guys have done it free hand with a hole saw, but it’s a good risk for ruining the manifold if anything goes wrong.

If you buy a new chrome fill tube, try to buy one in person so you can see it first. I bought the Edelbrock 4803 tube/cap from Summit Racing. Ultimately I received 3, and all three were defective with the bottom inch or so of the tube including the lower rolled edge missing. There wasn’t enough tube left to insure a tight grip in the manifold. Each return I explained what was wrong and included a picture, and they just kept sending more defective parts. I got tired of spending $5.00 on each exchange, gave up and had my son machine a correct tube out of aluminum.








If you want the chrome dome type breather cap, the one from Spectre is the best on the market. It fits tight, goes further onto the tube than other brands, and has a nice formed bead underneath that doesn't cut your fingers like the more expensive versions.

Amazon.com: Spectre 4280 Chrome Push-On Oil...
For the intake manifold side gaskets, I’ll never again use anything but Edelbrock Gasgacinch. It’s not only recommended, but works better than anything else I’ve ever tried.

http://www.summitracing.com/parts/EDL-9300/

[raycow]

If you don't want a hole in your valve cover there is still another fix. It works, and doesnt look bad, but is not for the faint of heart. Drill through the rear of the intake manifold directly into the lifter chamber and tap the hole for a nipple or PCV valve. Needless to say, you have to locate the hole carefully, and you don't want to do this with the manifold on the engine. Also, you should loosely attach a piece of sheet metal over the hole to act as a baffle and keep oil from getting sucked into the PCV.

Ray

[AslanRules]

Originally Posted by BMSJaX

I am currently running a Q-jet and I love it. Went from 9 MPG with a Holley 650 4bbl to 13 MPG. It does have the 'surge' or 'sputter' from idle cause it is 'over carbed' but it only requires a jet and rod change, which I am doing this next weekend. Q-jets are divorced or elec. choke but I did hook mine up to a manual cable and after some trial and error and tweaking it works great.
HEI is a must in my opinion.
If you can get the numbers off the front pad(in front of left head) you can probably find out what it came with originally.

Stop the presses, boys !!!!!

I'm heart-broken. I finally found the numbers off the front pad, as suggested. This is NOT the original 283 engine that came in this truck. The ID # is V0111CDH. According to my research, the engine was made at the Flint Engine Plant on January 11th. The CDH suffix indicates that the engine was made for a CAR, not a truck, and is either a 1972 350, or a 1985 305. The VIN on the pad does NOT match the VIN on the tag in the driver's door.

So.....THAT's why I couldn't find the Road Draft Tube hole in the back of the block BECAUSE THERE'S NOT ONE.

Looks like all bets are off and I'm back to square one. Can anyone tell if this is a 305 or a 350? Depending on that, what should I do regarding the intake and the new carb that I was going to put on it?

Is this a deal-killer, or is this just par for the course? (i.e. mis-matched parts)

I'm bummed. Any help or advice would be appreciated.

Thanks,

Randy

[markeb01]

Don't be bummed, that's not bad news, just different information. If you still choose the put on a new Edelbrock manifold and carb, the intake ports will actually line up better. You can skip the oil fill tube and just install any late model valve covers with breather holes. The only downside would be if you had really wanted it to be an original numbers matching truck.

Hopefully someone else has the answer on the 350/305 question.

[raycow]

There should be a casting number and date on the top rear of the block behind the intake manifold. Since you have already decoded the stamping in front, the casting date will give you the year for positive identification.

Ray