70 LT1 fuel lines

[Dennis D.]

Since being home is the new normal for now, thought I'd install the beautifully restored Holley Phil did for me.
Have to ask a dumb question, so I may as well ask two....

Is there a way to get the 2 lines from the block to the carb off without removing the carb? (unthreaded pump to block line already)

2nd, is it possible to put those lines on the wrong way?( carb to block, block to carb) Have a leak at the forward block line I can't seem to get to stop.

[Erich M.]

Re: 70 LT1 fuel lines

Dennis,

I assume you're talking about the lines that run from the block to the primary and secondary bowls. The fuel pump discharge line runs into the block. Many years ago I tried to disconnect both carb lines from the block with no luck. I was afraid to strip the flare nuts in the process of removing the lines...so I gave up. I was told that the only way to remove the lines from the block was to remove the entire assembly and apply heat. I didn't want to do that.

I found the primary line seal to be finicky. In order to seal it when replacing the carb I evenly tighten both lines on the carb while keeping the carb nuts loose. I also start the flare nuts in the carb by hand to be certain of not cross threading them.

Hope this helps!

Erich Meyer
72 LT1, original owner, Bowtie & Top Flight

[Paul Y.]

Re: 70 LT1 fuel lines

Dennis,

I assume you're talking about the lines that run from the block to the primary and secondary bowls. The fuel pump discharge line runs into the block. Many years ago I tried to disconnect both carb lines from the block with no luck. I was afraid to strip the flare nuts in the process of removing the lines...so I gave up. I was told that the only way to remove the lines from the block was to remove the entire assembly and apply heat. I didn't want to do that.

I found the primary line seal to be finicky. In order to seal it when replacing the carb I evenly tighten both lines on the carb while keeping the carb nuts loose. I also start the flare nuts in the carb by hand to be certain of not cross threading them.

pe this helps!

Erich Meyer
72 LT1, original owner, Bowtie & Top Flight

I use the flare nut wrench as a handle and bend the line to accommodate the hand screwing of the flare nut after the carb is bolted down on the intake. That way it is always easy on or off the next times. It usually does not require much adjustment at all. From then on it is easy to get it started and hand tightened with no extra torque to compromise stripping the nut.

[Dennis D.]

Re: 70 LT1 fuel lines

Thanks Erich.
The line from the pump seals fine. So does the rear line from the block to the secondary bowl. In fact the primary bowl line seals at the bowl. It's at the block I cant get it right.

I installed the 2 bowl lines and block, (loosely), while the carb was off. Then reattached the pump line to the 3 way block , (also loosely), once the carb was on the manifold unbolted.

Then I tightened the carb nuts, and evenly tightened the line flare nuts.

Ordering a new line set. Just wondering if theres a simple way to R&R .

[Dennis D.]

Re: 70 LT1 fuel lines

Great idea Paul

[Patrick B.]

[Gary S.]

Re: 70 LT1 fuel lines

Dennis,
I had virtually the same problem with my 72 LT-1 when I did some work on it just yesterday. On start up, the secondary bowl fuel line would not seal to the large 1" nut on the bowl. I initially thought it was the large gasket on the filter nut but when I swapped the nut from front to back, the problem persisted. This is on an (assumed) original fuel line from the block to the fuel filter inlet. A new line is ordered but the double flair fuel line should seat without issue. It DOES NOT. I have tried this perhaps 4 or 5 times and it still won't seal even though I have done this many times over the years. I have assumed that this is now the flared end. No way to verify this though and, as I said, a repro line is on the way.

Gary S.

[Dennis D.]

Re: 70 LT1 fuel lines

Are they original lines or repro lines that are giving you a problem? I have purchased two sets of repro lines for my 67 435 and neither fit right. I did quite a bit of rebending to get an acceptable fit. I never had the original lines that I assume would have fit better. If yours are original maybe all you need is one of the copper flare washers that Granger’s sells to seal a worn T-block.

Patrick....I was just looking at these. Did know where to get them. Would you know the size needed?
flaretite.jpg

[Dennis D.]

Re: 70 LT1 fuel lines

Yup Ordering at set too Gary

[Gary S.]

Re: 70 LT1 fuel lines

Dennis,
Where did you order yours from?

[Dennis D.]

Re: 70 LT1 fuel lines

Waiting to hear back from Chicago Corvette

[Ed H.]

Re: 70 LT1 fuel lines

Any chance you have stainless lines? If so, very difficult to get to seal. Other than that fiasco, I've not had a problem.

[Dennis D.]

Re: 70 LT1 fuel lines

Not stainless Ed. No issues before.
Thought sealing at the bowls would have been the issue ,since there are new inlet nuts .

[Dennis D.]

Re: 70 LT1 fuel lines

Ok think I sorted it out.
BTW, I was able to remove just the primary bowl line to 3 way block. Loosened the fitting and had slack to remove the pump line from the 3 way block. Loosened both bowl lines at the 3 way block, and when I loosened the line from the primary bowl there was enough slack to completely remove that line.

Looks like there's some damage inside the front 3 way block sealing surface . The line end looks OK, but a bit gunked up.

Screenshot_20200401-142631_Gallery.jpgScreenshot_20200401-142539_Gallery.jpg

[Patrick B.]

Re: 70 LT1 fuel lines

Patrick....I was just looking at these. Did know where to get them. Would you know the size needed?
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