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-   -   '69 bubba radiator setup and fuel pump questions (https://www.corvetteforum.com/forums/c3-general/2489168-69-bubba-radiator-setup-and-fuel-pump-questions.html)

94hokies 12-16-2009 04:38 PM

'69 bubba radiator setup and fuel pump questions
 
Working thru the basics on a new '69 and pulled out the radiator and support to run new brake lines. Did not think much of it, put on the side and now getting back to taking a closer look and referencing the manuals to see how far from stock the previous owner strayed.

Well we're pretty far off, the core support is the mid-70's with the wider ledge along the bottom and I am assuming the radatior matches it, as it does not look like the replacement '69s I've seen listed. Also removed was any recovery tank.

I'd like to get a hold of the right parts if I can find any good deals, but if not, how bad is this setup going to be mechanically for a 427 to be a driver?

Side question, it has the fuel pump with no return vent outlet, but the car is equipped with dual tubed gas tank (of which I just ordered a new one today). Same deal, I'd like to put the appropriate pump in there, but what is the impact of leaving the current one in place?

Thanks

Faster Rat 12-16-2009 05:42 PM

Nobody currently makes a reproduction brass/copper radiator for a '69 BB. They don't have a radiator cap and you need an aluminum surge tank. I just bought an aluminum "Direct Fit" radiator from Dewitts and had them paint it black. As far as the core support goes, I believe all that matters is that you have 27.5" between the supports to fit the radiator. Doc Rebuild sells the seal kits, not sure who sells the fan shroud, maybe Paragon.

The fuel pump for a BB just has an inlet and outlet. The outlet goes to the bottom inlet of the GF-432 fuel filter, the top outlet goes to the carburetor and the other small fitting goes to the fuel return line. All these parts are available from Paragon.

DUB 12-16-2009 05:58 PM

Fisrt off...fill out your personal profile so members know basically what part of the country you live in...because Washington state or Maine is different than Florida

It is all depending on if you are worried about FACTORY CORRECT or not.

Dealing with the radiator..and not knowing where you live...if you are not concerned about originality and want a radiator that is going to cool better than the factory design (copper/brass)...I would choose an aluminum radiator that will work in the support that you have now. Just make sure that you also obtain the rubber/foan seals that go between the radiator and the support so the air will pass through the core of the radiator instead of deflect or cavitate. This may also require you to install the seals that would seal the underside of the hood to the upper radiator support. They are important and are needed to make sure that the fan is pulling air through the core...as it was designed. Without them...you may or may not have overheating issues. This also includes the lower plastic air dam located in the valance area.
"DUB"

I do know that an assembly manual will have all the iunformation on how parts were connected and assembled. They are cheap and very useful. I do not have a manual here at home...but I do at work...and I can not remember how the big block set-up is right off the top of my head. BUT I do know that the small block has a fuel filter that has the return line provision in it so you can connect the return line from the filter to the factory line on the frame...with the metal line that came in with this set-up for a small block. The set-up for a small block was designed to work in conjunction with the smog pump. So with the set-ups I do... I make a bracket, and mount it on teh engine. Then bolt it to the clamp the goes around the fuel filter and keeps it solidly mounted...due to most if not all of the 69's I work on do not have the smog pump any longer.

94hokies 12-16-2009 06:45 PM

Thanks for the feedback. Primary goal is to make it a safe reliable driver. If in that path I can take the opportunity to replace incorrect parts with more accurate versions at reasonable cost, that would be my preference of course. I have the AIM for the '69, which is what tipped me off on the radiator support being wrong for the year. It does have the plastic shroud that matches whatever year the support/rad combination originally came from, though the rad does not have the 90 degree draincock making it impossible to spin to drain when attached to the support.

There is not even a plastic recovery tank installed, just a free hanging drain tube.

The two fuel system lines run from the tank up to the engine compartment and the vent line is currently just capped off with a screw and hose bracket, not attached to anything engine-side. The car did sit for 8 yrs, so was leaning towards replacing the fuel pump when I get into prepping the engine to restart. Figured that would be the time to put in a duel line pump if that was the right one. It is a CE engine and the motor spec on the gas tank paperwork was unreadable, so not sure what was original engine size.

Faster Rat 12-16-2009 07:07 PM

If the engine still has the Rochester Quadra-Jet, then the fuel return line from the filter needs to be hooked up the tank. Small blocks also had Q-Jets, so your car could have originally been a small block. I bought a clamp for the fuel filter, but it does not fit anywhere without the smog pump bracketry. I also have not been able to confirm anywhere (Assembly manual or NCRS Technical Discussion Board) that the fuel filter on a '69 BB did in fact have a clamp, nor exactly where it would attach.

The Dewitts radiator will set you back around 5 big ones. The aluminum surge tank another buck and a half, plus mounting bracket, straps, bolts, hoses and clamps.

Mike Ward 12-16-2009 08:15 PM


Originally Posted by 94hokies (Post 1572449948)

There is not even a plastic recovery tank installed, just a free hanging drain tube.

Corvettes prior to '73 did not have recovery tanks.

not a '76 12-16-2009 08:24 PM

my '69 corvette has a '76 small block radiator and support.

At times the car would get hot, but there were a lot of other reasons for that. (Bad fan clutch and sludge-filled block to name a few) Since the rebuild i have not had a chance to drive it.

I would put a recovery tank on the car somewhere somehow so that the core remains completely full of coolant and i would not worry about the 'right' parts until a getting hot problem presents itself.

you could probably hack a surge tank somewhere hidden for very short money.

Easy Mike 12-17-2009 10:08 AM


Originally Posted by 94hokies (Post 1572449948)
...I have the AIM for the '69...

Use the AIM for the original part number of the correct radiator support and the original radiator. With those, you should be able to find correct replacements.

If memory serves, your car probably had a 26" or 27" 4 row copper and brass Harrison radiator.

http://www.dewitts.com/pages/categor...s.asp?catID=16

:)

Mike Ward 12-17-2009 10:11 AM


Originally Posted by not a '76 (Post 1572450889)
I would put a recovery tank on the car somewhere somehow so that the core remains completely full of coolant and i would not worry about the 'right' parts until a getting hot problem presents itself.

you could probably hack a surge tank somewhere hidden for very short money.

Why would someone put both?

94hokies 12-17-2009 01:58 PM

This has been great info, thanks all. I'm thinking of staying with the current radiator for the time being and just finding a plastic recovery tank to attach where the original aluminum tank was. Don't care about looks, just wanna be dependable.

Found out what was throwing me off on the fuel system. At some point he removed the special fuel filter that '68/69 used that had a port for the recovery line. Read that big block fuel pumps don't have the extra port either, leaving no place to hook the return line up to, so he blocked it off. Looks to be a '74 QJet in there now, and from an automatic originally, now sitting in a 4-speed (will this be a problem?). He wrapped the pump to carb fuel pipe in rubber hose, I'm assuming to try and protect it from the block heat.

Think I could buy the '69 3 piece line kit and GF432 filter, reconnect the return and still connect to the 74 QJet?

AvRog 12-17-2009 04:11 PM


Originally Posted by Mike Ward (Post 1572450786)
Corvettes prior to '73 did not have recovery tanks.

Per the AIM and my car there is a recovery tank, called a radiator supply tank, metal, installed on the right fender well.
Later, Rog.

Mike Ward 12-17-2009 04:30 PM


Originally Posted by AvRog (Post 1572459175)
Per the AIM and my car there is a recovery tank, called a radiator supply tank, metal, installed on the right fender well.
Later, Rog.

That's not a recovery tank, that's an expansion tank. Very different animals, very different purpose. Many people use the the terms interchangeably without knowing the difference.

All Corvettes prior to '73 had expansion tanks either external or internal to the rad, but did not have a recovery tank. '73 and up Corvettes had the opposite.

No Corvette had both.

Faster Rat 12-17-2009 07:18 PM


Originally Posted by 94hokies (Post 1572457879)
This has been great info, thanks all. I'm thinking of staying with the current radiator for the time being and just finding a plastic recovery tank to attach where the original aluminum tank was. Don't care about looks, just wanna be dependable.

Found out what was throwing me off on the fuel system. At some point he removed the special fuel filter that '68/69 used that had a port for the recovery line. Read that big block fuel pumps don't have the extra port either, leaving no place to hook the return line up to, so he blocked it off. Looks to be a '74 QJet in there now, and from an automatic originally, now sitting in a 4-speed (will this be a problem?). He wrapped the pump to carb fuel pipe in rubber hose, I'm assuming to try and protect it from the block heat.

Think I could buy the '69 3 piece line kit and GF432 filter, reconnect the return and still connect to the 74 QJet?

If your current radiator has a pressure cap, then you can install a plastic recovery tank for the overflow.

I believe the Q-Jet for an automatic transmission has an idle stop solenoid, which is not required on a manual transmission.

The pump outlet goes to the fuel filter inlet via a metal line, then via a metal line to the carb. No need to wrap in rubber hose. If vapor lock is an issue, then you need to insulate the carb bowl from the exhaust heat crossover in the intake manifold. A metal gasket can be used, or block off each side of the crossover with plugs, or both.

The three metal fuel lines and the filter should do the trick, along with rubber fuel lines and clamps to connect to the car's metal fuel lines back to the tank.

CoolShark 12-17-2009 11:26 PM


Originally Posted by Mike Ward (Post 1572459375)
That's not a recovery tank, that's an expansion tank. Very different animals, very different purpose. Many people use the the terms interchangeably without knowing the difference.

All Corvettes prior to '73 had expansion tanks either external or internal to the rad, but did not have a recovery tank. '73 and up Corvettes had the opposite.

No Corvette had both.

All Corvettes prior to 73 did not have expansion tanks. My '72 LT-1 w/AC never had one.

Mike Ward 12-18-2009 12:22 AM


Originally Posted by CoolShark (Post 1572463455)
All Corvettes prior to 73 did not have expansion tanks. My '72 LT-1 w/AC never had one.

Nope sorry. The expansion tanks are internal to the radiator as stated above. That's the 'airspace' left inside when filled to the correct level. First time owners of older Corvettes are frequently unfamiliar with systems where the rad must NOT be filled completely, then panic when it pukes after shutdown.

Easy Mike 12-18-2009 09:19 AM

As a rule of thumb only, if the stock radiator has a cap, an expansion tank on the fender skirt was not installed. All the big 4 row Harrisons have caps.

If the radiator does not have a cap, the expansion tank is installed to allow for filling coolant. The stacked plate aluminum radiators usually do not have caps.

Regardless, check the AIM for the specific requirements of your specific radiator.

:)

Mike Ward 12-18-2009 11:28 AM


Originally Posted by Easy Mike (Post 1572465385)
As a rule of thumb only, if the stock radiator has a cap, an expansion tank on the fender skirt was not installed. All the big 4 row Harrisons have caps.

If the radiator does not have a cap, the expansion tank is installed to allow for filling coolant. The stacked plate aluminum radiators usually do not have caps.

Regardless, check the AIM for the specific requirements of your specific radiator.

:)

That's correct, except that I believe the OP has installed a newer style rad that was designed to operate with a recovery tank (ie '73 and up config)

If so, then the correct type rad cap will be required as will a non-pressurised tank and suitable tubing.

AvRog 12-18-2009 03:41 PM


Originally Posted by Mike Ward (Post 1572466760)
That's correct, except that I believe the OP has installed a newer style rad that was designed to operate with a recovery tank (ie '73 and up config)

If so, then the correct type rad cap will be required as will a non-pressurised tank and suitable tubing.

Ok. so how can I tell if I should be using the radiator supply tank on my fender well? I do have an overflow line to the tank. there is also a return (what I assume is a return) on the tank, not in use. At the rad cap there is a line capped on my rad that I thought I should connect to the tank unused connection. Should I connect?
Later, Rog.

Mike Ward 12-18-2009 08:10 PM

Very simple. If you have a cap on your rad, ditch the expansion tank. It serves no purpose.

AvRog 12-19-2009 11:10 AM


Originally Posted by Mike Ward (Post 1572471541)
Very simple. If you have a cap on your rad, ditch the expansion tank. It serves no purpose.

Why is there a return line on my rad below the cap?


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