'67 Expansion Tank Hose Tie Straps

[David P.]

Hello to All,
I have a question (actually two) on the 3 tie straps that secure the radiator to expansion tank hose on a '67 327:
1. Can anyone direct me to some good photos or drawings of the correct routing of the hose and the correct way to install the tie straps?
The assembly manual does not help too much.
2. I purchesed repro tie straps from Corvette Central. The nubs on the straps are too small for the holes in my inner fender. The straps will not stay in the hole.

Are my holes in the inner fender worn to oversize? Or are the strap nubs too small of a diameter?

Thanks in advance.

DAP

[David P.]

Re: '67 Expansion Tank Hose Tie Straps

Hello Again to All,

Not sure if this is an unpopular question or if it has been asked before.

Anyone with knowledge, please let me know.

I have figured out the routing for the hose and have solved the apparantly common problem of enlarged holes.

Only remaining question is:

When proprerly installed, do the straps point "up" or "down". That is, is the "loop" of the strap that holds the hose pointing "up" or "down"?

I can post a pic if the question is not clear.

Thanks in advance.

DAP

[Scott S.]

Re: '67 Expansion Tank Hose Tie Straps

Hello Again to All,

Not sure if this is an unpopular question or if it has been asked before.

Anyone with knowledge, please let me know.

I have figured out the routing for the hose and have solved the apparantly common problem of enlarged holes.

Only remaining question is:

When proprerly installed, do the straps point "up" or "down". That is, is the "loop" of the strap that holds the hose pointing "up" or "down"?

I can post a pic if the question is not clear.

Thanks in advance.

DAP

Dave, good questions, the JGs are silent on the direction of the strap.

My original balance hose, with "GM" logo followed by a square box (all blue ink), at 1-7/8" intervals, still has one original GM 3825551 retainer strap attached to the hose. It is the tie strap closest to the expansion tank, and the long end is pointing downward.

If you check Adams p. 421 (bottom LH photo), it shows a 1967 L79 with the expansion tank and balance hose visible, and the tie-strap closest to the expansion tank is pointing downward. The middle LH photo shows the other side of the engine bay, and it appears that the same tie-strap is used to secure the wire harness to the LH inner fender (shown on UPC 6-B4, but not called out by part number). This picture is much clearer, and the long end of the tie strap is again pointing downward.

[David P.]

Re: '67 Expansion Tank Hose Tie Straps

Scott,

Thanks for the info. I gave up looking before I got to Adams pg. 421. Unfortunately, my copy of that picture is too dark to make out the tie strap on the expansion tank hose. I can see the wiring harness strap on the other side though.

So here is a question: I see the long end pointing down on the wiring harness strap on the drivers's side, as you stated. In this case I am going to say that this strap is in the "2nd" hole making the tightest possible fit on the "skinny" wiring harness.

On your car, for the expansion tank hose, is the tie strap also in the "2nd" hole? Even though the hose is quite a bit larger in diameter than the wiring harness? On my new hose and new strap it looks like it will be difficult to get it into the "2nd" hole and the strap might crimp the hose.

Thanks again!

DAP

[Scott S.]

Re: '67 Expansion Tank Hose Tie Straps

Scott,

Thanks for the info. I gave up looking before I got to Adams pg. 421. Unfortunately, my copy of that picture is too dark to make out the tie strap on the expansion tank hose. I can see the wiring harness strap on the other side though.

So here is a question: I see the long end pointing down on the wiring harness strap on the drivers's side, as you stated. In this case I am going to say that this strap is in the "2nd" hole making the tightest possible fit on the "skinny" wiring harness.

On your car, for the expansion tank hose, is the tie strap also in the "2nd" hole? Even though the hose is quite a bit larger in diameter than the wiring harness? On my new hose and new strap it looks like it will be difficult to get it into the "2nd" hole and the strap might crimp the hose.

Thanks again!

DAP

Dave,

Yes, the tie strap is secured in the 2nd hole from the end. It squeezes the expansion tank balance hose just slightly, which may be visible in the pictures below.

It is likely that reproduction hoses (and tie straps) are not exactly the same size as originals. I have not yet tried to fit repro tie straps to the original hose, or a reproduction hose, or an original tie strap to a reproduction hose.

[David P.]

Re: '67 Expansion Tank Hose Tie Straps

Scott,

Thanks!
"A picture is worth 1000 words!"
Thanks for posting them!

DAP

[John H.]

Re: '67 Expansion Tank Hose Tie Straps

David -

The Assembly Manual (UPC 11/13, sheet A4) shows the two retainers closest to the expansion tank with the loop end down and the one near the hood hinge with the loop end up. The four retainers on the LH side for the forward lamp harness (UPC 12, sheet A10, item #24) are all shown with the loop end up.

[Scott S.]

Re: '67 Expansion Tank Hose Tie Straps

David -

The Assembly Manual (UPC 11/13, sheet A4) shows the two retainers closest to the expansion tank with the loop end down and the one near the hood hinge with the loop end up. The four retainers on the LH side for the forward lamp harness (UPC 12, sheet A10, item #24) are all shown with the loop end up.

John,

Getting the details right is half the fun, and I hadn't even thought about this one until Dave brought it up. Thanks always for the correction and instruction

[David P.]

Re: '67 Expansion Tank Hose Tie Straps

John,

Thanks for pointing that out.

I had searched the Assembly Manual and somehow managed to miss it.

So from UPC 12, sheet A10, #24 it looks like the LH side straps for the wiring harness are indeed shown in the second hole.

It is not quite as clear on UPC 11-13, sheet A4 for the expansion tank hose.
It actually almost looks like they may be in the first hole making for a larger diameter "loop" for the hose.

So what is the official ruling for the hose tie straps? 2nd hole likes Scott's original (smaller "loop")? Or 1st hole making a larger loop?

Thanks again to all!

Sincerely,
DAP

[John H.]

Re: '67 Expansion Tank Hose Tie Straps

It is not quite as clear on UPC 11-13, sheet A4 for the expansion tank hose.
It actually almost looks like they may be in the first hole making for a larger diameter "loop" for the hose.

Dave -

The issue of the retainers on the expansion tank hose is further confused by the notation on UPC 11-13, A4 that says "see UPC 12" for the retainers. That's an error in both the '67 and '66 Assembly Manuals, as neither the '66 or '67 had any harnesses on the RH side that would be shown in UPC 12; that note carried over from the '65 AIM, which had the alternator and the engine harness on the RH side of the engine and on the RH inner fender.

If you look at that sheet in the '65 AIM (UPC 12, sheet A8), it shows all three of the retainers holding the expansion tank hose and engine harness installed with the loop "up".

[Larry M.]

Re: '67 Expansion Tank Hose Tie Straps

Dave -

If you look at that sheet in the '65 AIM (UPC 12, sheet A8), it shows all three of the retainers holding the expansion tank hose and engine harness installed with the loop "up".

David:

Finally got the car cover off my 1967 small block car and looked at how these hose straps are mounted. My car is very low mile and mostly original, although just about anything could be changed after 44 years.

Anyway, the three straps are mounted with the loops pointed UP, just as John H stated above. Also, all three straps use the mounting hole in the strap that provides for the bigger/larger loop, which provides more room for the expansion hose.

If the strap nearest the RADIATOR were mounted with the loop down, it could/would interefere with the hood support when the hood is down. At least on my car.

If the strap nearest the EXPANSION TANK were mounted with the loop down, it would not fitup properly to the expansion tank nozzle.

So I guess having the loops UP is the correct choice for all three straps.

I have also found that the reproduction straps will break after about 3 months of use. Probably a combination of the heat from the hose and engine compartment, and the material of construction of the repro straps. Original ones do not break. I have sourced reproductions from 3 or 4 different companies and still had the problem. Finally got some old originals and installed them. No problem so far.

Larry

[David P.]

Re: '67 Expansion Tank Hose Tie Straps

Hi Larry,

Thanks for the concise response, that was extremely helpful!

As a note, one of my brand new repro. straps broke at the hole the fisrt time I tried to install it!

Thanks again to all.

DAP

[Neal K.]

Re: '67 Expansion Tank Hose Tie Straps

John, Scott and Larry,
I have read this thread 3 times and am still confused because of Larry's last post.
Am I correct that the 2 straps closest to the expansion tank have the loops pointed down and that the strap closest to the radiator has the loop up? In all cases the 2nd hole in each strap is used which results in the smallest loop?
Lastly, does the expansion tank hose get routed to the behind the hood support mounting bracket(ie between the hood support and the drip rail), which is what it looks like to me in the drawing on page 11-13 A4 of the AIM, or below the hood support mounting bracket?
A picture of the entire passenger side inner fender skirt with everything hooked up for an L-79 with C60 would be a blessing.
Thanks
Neal

[Scott S.]

Re: '67 Expansion Tank Hose Tie Straps

John, Scott and Larry,I have read this thread 3 times and am still confused because of Larry's last post.Am I correct that the 2 straps closest to the expansion tank have the loops pointed down and that the strap closest to the radiator has the loop up? In all cases the 2nd hole in each strap is used which results in the smallest loop?Lastly, does the expansion tank hose get routed to the behind the hood support mounting bracket(ie between the hood support and the drip rail), which is what it looks like to me in the drawing on page 11-13 A4 of the AIM, or below the hood support mounting bracket?A picture of the entire passenger side inner fender skirt with everything hooked up for an L-79 with C60 would be a blessing.ThanksNeal

Neal,

My understanding is that all of the black plastic push-in type straps for the balance hose along the RH inner fender are installed with the loops oriented upward, which agrees with what Larry said: "Anyway, the three straps are mounted with the loops pointed UP, just as John H stated above."

The second hole from the tip (resulting in the smallest loop) gives a very snug fit, and that's how mine was, but I don't know if that was how they came from the factory. I suspect the same loop size would be used for all three straps, since they're all securing the same constant diameter hose.

I believe the expansion tank hose (a.k.a. balance hose) routes behind or outboard of the hood support and hood support bracket, going between the hood support and the drip rail. This is how it is illustrated in the 1965 AIM, but they removed the actual drawing of the hood support for the 1966-67 AIMs.


Picture 1: 1967 Corvette, L79 with C60, auction photo of claimed 2001 Bloomington Gold Benchmark Award winner

Picture 2: 1965 AIM (UPC 11-13-A4) showing the hood support in place, which the 1966-67 AIMs omit


That's my understanding at this point, if I'm wrong, somebody please explain.

[Neal K.]

Re: '67 Expansion Tank Hose Tie Straps

Scott,
Thank you
Neal