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Topic: HWH 680 Manifold Internal Airflow Diagram (Read 402 times) previous topic - next topic

HWH 680 Manifold Internal Airflow Diagram

What actually happens inside the six pack has always been a bit of a mystery to me as I've been chasing down leaks and I know I'm not alone; it's a bit of a black box. I emailed HWH a couple weeks back trying to find out and never heard back. Low and behold, as I was sifting through my owner docs looking for Bose stuff, I found this!

I don't think I've seen this shared yet so I uploaded it to the media archives: https://www.foreforums.com/index.php?action=media;sa=item;in=4895

One thing it does confirm for me, if I'm interpreting it correctly, is that leaky pressure switches could cause leak down in the front.

1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: HWH 680 Manifold Internal Airflow Diagram

Reply #1 –
Quote from: Elliott –
What actually happens inside the six pack . . .

You could, if you wanted to do so, give that page to your local Festo sales man and he could give you a bill of materials for the complete assemble all new.  Ask him 'About how much" before you ask him to do all the heavy lifting.  Like the guy at the dealership said when I asked for a new S.E.V. Marchal alternator for my SAAB, "Are you sitting down?"
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: HWH 680 Manifold Internal Airflow Diagram

Reply #2 –
Quote from: Elliott –
One thing it does confirm for me, if I'm interpreting it correctly, is that leaky pressure switches could cause leak down in the front.
I confirmed this today by pulling one of the pressure switches while there was still a bit of pressure in one corner.

Also, the other pressure switch was fairly loose (actually the 45 degree fitting it screws into) and it was crossed threaded into the fitting. It also happens to be for the corner that leaks down so I'm really hopeful this is the final leak I've been hunting for the front. Famous last words that I've said many times now...
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.