70 GS Heater Hose Routing w/ AC

I found this in the 70 Chassis Manual. I see many cars with the small hose run under the AC compressor bracket and other variations. What is correct? Is there a problem with the above picture that I am missing or a reason why folks don't follow it?

 

If you took that out of the 70 Chassis Manual, then it would have been developed before the 70 model year even started and won't work for what you are trying to do.
I can already see things on there that were never used on a 70 car.

You need to look at the Assembly manuals. They show the routing/clamps/etc.
Duane

 

Thanks Duane - the assembly manual is very close to that - I looked when I got home today... Page 1-11 6. It is confusing - for example: it shows the 3/4 hose on the outside next to the blower motor. It's the page for the refrigerant lines but is the only plate I see that shows the heater hoses. Do you a have a pic of a "correct" routing?

 

The small heater hose has to run on top of the AC bracket because it is attached to the heater valve that rests on top of the AC bracket with that rubber ring, The bigger 3/4 inch hose runs right next to it and there is a hose cushion and metal strap that holds hoses together. Make sure the bigger hose doesn’t come in contact the alternator as the heat will dimple the hose causing weakness. Especially if you have a super heat alternator like Jason!

 

That canister on the passenger wheel well is funky. Never saw that on a car for sure in 70.

 

Here is a 70 magazine picture. It gives a good idea.

 

I seem to remember there is a mistake in 70 Assembly Manual and hoses are reversed so 71 would be correct.

 

Here is the 70 assembly manual. Note the weird routing of the big hose on top of heater valve.

 

Now here is the clearer 71 picture. You will notice the 70 magazine picture is more like the 71 diagram. I believe this is correct even for 70. Also note the vacuum hose is routed over the top of valve and through metal strap. I found most original cars like this.

 

That, short 5/8” length of hose from intake to heater valve needs to be 5.5 inches long.

 

Ok, here is the perfect picture for you.

 

One more interesting observation. I have found both big and small inner diameter foam sleeves. The size you have dictates the hose it goes on.

 

Excellent - thanks! I notice on mine the AC bracket is further forward so the valve does not rest on it - maybe that's because its an engine out of a Riv??? This information will help - thanks again!

 

I believe you are correct. Riviera has some different brackets. I would hunt for correct one.

 

70 bracket has no hole for ground wire and screw like 71-72. You can see where 70 ground attaches at front in picture.

 

Good pics Who’s Black car. Stunning. My hoses are all wrong . length to long . I have to fix and make correct soon. Arghhhh. excellent Thread

 

I was at a car cruise with the Buick and a Member of the forum was looking at my car . Can’t remember his name nice guy. And explained to me that the little black donut has to rest on the A/C bracket in that little smoothed out groove. Did not know . Most of you do. That’s how you get the correct length of the one heater hose.

 

I am not sure on that but the factory spec for the short piece of hose is 5 1/2 inches. It puts it where it puts it.

 

Here is all you need for lengths. This is the late 71 chart. The 70 to early 71 chart had some slightly different lengths. Some were a bit too short and were strained. I have tried them all on both 70 and 71 cars. This chart works best for both 70 and 71. Probably 72 as well.