voscreature

Hi,

PO of my 68 installed an electric fuel pump and a new tank without the ventilation nipple.

I plan to restore it back to 100% (well...) original in the fuel system. Does anyone have some good pictures of the region around the filter bracket attachment on an original 68? I'm suspecting I might not have an original air pump and bracket...hmmm....

The return line concerns me somewhat. The tank the PO stuffed in was a new one with OLA Co. logo....annoying to remove it to buy a new one just for the return line. Perhaps I must draw a line somewhere when it comes to this project...

Thanks.

voscreature

Anyone with a 68 427/390 that might have time to snap a photo of the filter/lines mounted to the air pump bracket?

Stupid question perhaps...the "vapor return line" from the filter....does raw gas flow in this line or can I temporarily just vent it to the atmosphere until I have time to remove tank and fix the missing return line nipple.

/Martin

MelWff

it's gas not vapors. Dont you have a steel line going from the pump to the filter and another steel line going from the filter to the carburetor that supports the filter?

voscreature

I have a set of new lines, filter and filter bracket and a new mechanical pump. When I got the car an electrical pump was hooked up in the rear of the car together with an adjustable fuel pressure regulator before the carb. The return line was ths unused, but is still there and in good shape. Unfortunately the tank has been replaced and unfortunately to one without the nipple in the upper passenger side. But I can probably install a nipple in the tank some way or other...and reconnect the return line.

But a picture of the fuel filter and bracket would be helpful. I'm not 100% sure I have the original air pump and brackets...

Martin

Faster Rat

Martin
Forget about that bracket...it is for a small block application only. There are probably thousands of them laying around on the workbenches of big block owners, because all the parts houses sell them as repros. The NCRS TIM & JG is wrong in regards to the big block. The AIM does not show any filter mounting bracket for the L36. The GF-432 filter is supported quite well by the metal line from the pump outlet and the metal line to the carb inlet. Here is a picture of my '69 L36 that happens to not have the A.I.R. pump and it's mounting bracket.

voscreature

Thanks for the info and picture. The only thing that bugs me is page H341 in my 68 AIM. It seems like the bracket is there for the L36, thats whats so confusing. But the AIM is clearly not 100% either...just look at the vent shut off ***** that was not used in 68 but are clearly shown in the AIM...

Faster Rat

Page J207 of the '69 AIM shows the small block/base motor installation and clearly identifies the filter and bracket, even in detail View A. Page J367 shows the L36 installation and does not show the bracket, only a clip that holds the two metal lines together underneath the filter. This subject has been discussed before on this forum and the NCRS board as well.

My brother-in-law lives in Grums. Anywhere close to you? Asked him to find me a wealthy Swede to buy my car. He said that would probably be a worker on one of those Norwegian offshore platforms...

voscreature

Grums is not too far away from here. About 2 hours drive. A lot of people here work in Norway also. Have you ever been in Sweden?

Too bad I do not have the return nipple in my gas tank. But I guess I can remove the tank and install a nipple....feels a bit too weird to buy a new tank ONLY becuase of that...the current tank is brand new with OL logo and all...

PRNDL

That is a bit of a sticky wicket. I am big on bubba... errr.. I mean I am a big proponent of novel, safely engineered solutions , however, I wouldn't try to add a nipple on to a fuel tank. I went the other way - even tho my 68 fuel line was not and is not connected to the fuel return line, when I replaced my fuel tank I went with the original style tank and capped off the fuel return nipple. That way if I (or anyone else) wants to reactivate the fuel return line it will be easily attached.

I guess a new "correctly configured" tank would be quite expensive in Sweden. I think I got mine for less than $200, made in Canada, but without the logo.

Also, I think the reason nobody has helped you out with a picture of an L-36 with AIR is that the vast majority have removed the AIR pumps, and conversely, the vast majority of NCRS/factory original 68 bigblocks are tripower.

This is the best I can do, which unfortunately does not help, is this pic of a very original 68 L36 at a car show. Rare bird! I can't believe I didnt take more closeup pics of the area you are interested in.

PRNDL

Here is the tank you want, with the fuel return "nipple". Does your tank have an indent like that?

Faster Rat

Not yet, but visiting my roots is definitely on my bucket list. My fraternal grandmother emigrated from Malmo in 1903...came to the United States on the SS Mauritania and entered thru Ellis Island. My fraternal grandfather Lars (my middle name) came earlier from Norway. My maternal grandparents were both of Norwegian descent. There are many Scandinavian descendants in my native Minnesota and I grew up listening to all the Norwegian/Swedish jokes...mostly about Ole, Sven and Lena. Quite a folksy sense of humor.

voscreature

My tank has the indent but not the hose connection.

I discovered today why the electrical pump has been installed...the fuel pump push rod is stuck in the bore in the block. I just spent 4 hours trying to get it out of the bore but with no success. The cam pushes it out and I can with quite a lot of force push it back in but the fuel pump lever does not have enough force by its own...feels very ticky to get it out of the block. Hmmm...

voscreature

Last week I did get the pushrod out of the block with a custom made thin walled tube that I was able to gently tap over the pushrod through the installation hole. Then I could twist, turn and pull to get the pushrod out.

New pushrod in, new fuelpump, new fuel filter and new hard fuel lines. When starting the engine the new fuel lines leaked on ALL FOUR FLARES. After 2 days of frustration I gave up and reinstalled the old, non original setup until I get new fuel lines and hope for better luck.

They were not the SS type, but obviously the repros I had must have a too hard steel quality or incorrect flare, it was absolutely impossible to get them leak free, and I tried tightening HARD. What a disappointment and 2 days wasted. But I could feel something was wrong when snugging the fitting up, it was not possible to gradually tighten them harder, it "stopped" more distinct than usual. Tried all the tricks out there with teflon tape on the threads etc. etc., but futile.

Repros....



Martin

Faster Rat

I get frustrated with 37 degree inverted flare fuel line fittings as well. Seems that if the flare itself or the alignment is not absolutely perfect, it will leak. Differing hardnesses in the lines and fittings seem to affect the contact and tightness. Somebody told me to use a special thin copper crush washer beveled at 37 degrees in between the flare of the line and the fitting. Who knows, it could work. I've been trying to install a made up line with a tee fitting between the filter and the carb in order to get some fuel pressure readings when driving. Every time I tried cranking the engine I had fuel spraying all over. After an entire afternoon I gave up and put the system back to the way was. The entire house smelled like gasoline for a week.

PeteZO6

I'll probably get flamed for this, but you might try wrapping teflon tape around the threads of the fittings. Use it sparingly, only one wrap around the fitting, with no tape extending past the threads. The teflon tape "lubricates" the threads and lets you tighten the fittings more than with no lube of any kind. The tape makes a big difference.

Just don't over use it; if it gets past the threaded part of the fitting it can get into the gas and clock the needle/seat, or something else in the carb. You don't want that!!!


Pete

voscreature

I have ordered a new line kit from DocRubild. See how these lines fits...

Until I get a new tank with fuel return nipple - is it safe to plug the return nipple at the fuel filter? Or does that lead to a too high fuel pressure to the carb?

Martin

Faster Rat

I believe the fuel return line for Q-jet cars helps prevent vapor lock by allowing hot fuel to return to the tank. I don't think it has anything to do with relieving fuel pump pressure.

noonie

FYI
The stock flare for fuel lines and brake lines is SAE 45° double flare.
37° is primarily used in hydraulics, known as a JIC flare (single) and -AN has mimicked it with tighter specs, but interchangeable.

Sometimes you can use a 45° flaring tool to flare tubing used on a JIC steel fitting, you can torque it down tight enough to slightly reform the flare.

It might be best for you to test fit the lines with a steel fitting mounted in a vice first. Always lube the tube and fitting well before torquing.

Besides the vapor issue, the return line helps the pump stabilize the fuel pressure.
You can have a nipple welded or brazed into the tank. Look for someone experienced at repairing fuel tanks that have had fuel in them.

voscreature

Thanks for the info. I ordered a new set of lines from DocRebuild, they looked very similar to my previous set.

Today I installed them, and its absolutely leak free. FINALLY!

BUT! The absolutely most critical detail when installing was to grease the lines especially on the "neck" of the flare. When I did this I could easily snug up the fittings gradually, and not experience the sudden seize like before. That's a key thing in my opinion (and as pointed out by noonie). For now I run with a plugged return on the filter in front of the car. I guess it does not hurt anything?

THANKS again all for help and advice!! One more detail back to original on my car.

Martin

jm1968

Just a note on this...from what I can tell, my 1968 427/390 is original and did not come with a fuel return line. The original mechanical fuel pumps had only an inlet and outlet...no return line. The gas tank has no return. I think this is not the case with the higher horsepower big blocks, however, for whatever reason, the 390 HP is setup this way. I found this out when having to repair the fuel tank due to rust/leaking. If anyone has conflicting information would be interested in hearing because I am in the process of getting a new setup (fuel pump/carburetor, etc) but am not planning to use a return line.