Vacuum Accumulator? Hunting vacuum leaks

FarPoint · June 08, 2020, 08:54 PM

I found this under the hood, screwed to the underside of the front cowling area.
It's a perfect sphere about 4" in diameter, with two ports. One is clearly marked VAC, and has a hose attached. (I haven't traced it yet) The other port has a short section of an open ended hose attached - leading nowhere and no other open port in sight.
I've been tracking and repairing vacuum leaks - is this another one?
Is this some kind of vacuum accumulator, or buffer?
I doubt the one port is intended to be open.

ClydesdaleKevin · June 09, 2020, 08:29 AM

Yep. Accumulator.

Kev

Rickf1985 · June 09, 2020, 10:15 AM

Yep, that is another one, that would normally go to the heater controls or to the cruise control. Mine has two of those and one goes to the heater controls and one to the cruise controls. If your heater does not switch from heat to defrost then that is why. Or if your cruise doesn't work, there you go.

FarPoint · June 09, 2020, 11:29 AM

Thanks! Gotta admit - I was shocked that the cruise control actually works. So I guess its the heater - it is acting a bit weird - i did previously replace that vacuum line to the diaphragm on the throttle stop, and my idle RPM did come down to a manageable level.
Now I guess I'll have to decipher the rest of the vacuum rats nest under there.
Would the routing of those hoses actually be listed anywhere?

Rickf1985 · June 09, 2020, 05:39 PM

Quote from: FarPoint on June 09, 2020, 11:29 AM

Would the routing of those hoses actually be listed anywhere?

Yea, right! :)rotflmao :)rotflmao :)rotflmao :)rotflmao :)rotflmao :)rotflmao :)rotflmao :)rotflmao Seriously though I think these coach builders, all of them, not just Winnebago, would see a hose hanging down and say "oh crap" and just drill a hole right there where it meets the dogbox, firewall, floor, whatever to make it fit. Basically you just need to go the the heater control and work back towards the engine compartment and vice versa. I can tell you that the accumulator is for the heater if the cruise is working so that is a start. Now find the supply hose for the heater under the dash and trace it to a dead end and that should be somewhere in the vicinity of a hole in the direction of the accumulator. Mine comes straight down through the engine cover ahead of the dogbox, under the dash.

FarPoint · June 09, 2020, 06:18 PM

Well, it's definitely a vacuum leak - its sucking pretty hard even through the piece of black tape some PO or "Technician" had jammed in the end of the short hose. I stuck a screw in it for now - may explain a few other issues as well.
The only hose running to the canister is directly connected at the the base of the TBI on the back end, and connects to nothing else.

So - do you think that there's maybe a diagram somewhere of the heater controls and the vacuum hoses attached. Mine are various colors but I have no idea if one is missing or plugged in the wrong hole.

Standing by for emoji avalanche...

Rickf1985 · June 09, 2020, 09:28 PM

I have found that diagram in the past and I think it was for a Dodge pickup truck. If I remember correctly these use a Dodge heater control. Are you just looking for the supply line for the heater or are you looking for the entire heater circuit? The heater control is out of my Pace Arrow and I might be able to track the supply line in that one.

FarPoint · June 10, 2020, 01:01 AM

Thanks for the help Rick

Heater control doesn't work, so trying to figure out the correct connections and routing of the heater vacuum hoses, I guess.
That way I can possibly eliminate other errors or mis-routed hoses.

Rickf1985 · June 10, 2020, 11:38 AM

Well, Yours is a late 90's so I don't know if they were still using the Doge heater controls or not. But if you can compare the heater controls to pickup trucks from that general era from Dodge and GM you should be able to pin it down and then look up the vacuum diagram for that year pickup truck. I just came in from doing some stuff outside and I am beat! it is freakin' hot out there. But when I go out again I will look at the Pace Arrow and see if I can track down which is the feed line.

Rickf1985 · June 10, 2020, 01:30 PM

I just went out and looked at the Pace and the connector has red, black, blue and white lines on it. I couldn't see the accumulator on this one since it is not out front but I did see the actuator for the heater line with the completely disintegrated plastic line and that looked possibly blue or black. I kind of remember the white line being the feed line on mine but not positive. What I would do is trace the white line from the heater control and see where it goes. I am betting it heads towards the engine cover and either goes through or is broken off before. Probably through and broken off in the engine compartment from the heat. Once you see where it goes through you might be able to see it from inside looking up forward from the dogbox. That was what I did.

FarPoint · June 11, 2020, 01:20 AM

Will do as soon as IÃ¢â,¬â,,¢m back from my road trip. I have to do a bit of business next couple of days. See if I can get my economic recovery going here...

FarPoint · June 20, 2020, 11:19 AM

I've been exploring a bit underhood and searching out stray vacuum lines and anything else making sucking noises.
Found this "attached" to the heater bypass valve. You may be able to see the end of the green vacuum line remaining in the elbow. The other end of the green line was rotted off, not attached and goes to the heater control on the dash - or at least heads in the general direction of the dash - BUT has no vacuum when engine running. No matter what the position of the temp control.
More hunting to do - and so little room!!
On the positive side - the diaphragm on the bypass valve seems to work and the valve isn't seized.

FarPoint · June 23, 2020, 02:12 AM

Heater / vent / AC controls. Haven't discovered who the parents were yet. Dodge or GM.

Rickf1985 · June 23, 2020, 08:23 AM

That looks like a Ford control, Looks exactly like the one in my Mustang. I will go out and look at my 96 pick up once I get sprayed down for ticks.

FarPoint · June 23, 2020, 03:41 PM

Thanks Rick - Ticks? Big problem in your area? Disease a problem there? I moved over to Vancouver Island, specifically Nanoose Bay, and we're in tick central - notorious even for Vancouver Island. We have a TON of deer, and rabbits in my area. Not really worried about the food supply chain if it gets really weird - just step out the front door and it's on the hoof.
My dog was getting nailed regularly, despite being on the topical treatment Revolution - I tried her on the oral systemic treatment but she had a reaction.
Just not sold on the one prevents the bite, either. At that point you probably have one toxic puppy.
So Revolution is is - which supposedly kills the ticks after they bite but before they release their disease.
Maybe... but still unnerving to find a sick tick on the floor.
Stay well, and tick free. We have enough on our plate as it is.

Rickf1985 · June 23, 2020, 05:21 PM

Disease is a big problem here. I contracted Lyme's 20 some years ago. Now there are several others, I just had to get the dogs vaccinated for Leptospirosis. We also now have rocky mountain spotted fever and one other main tick borne disease I can't remember. Both of my dogs get the Sempirica pills. The newest dog came from Moscow, Russia in Feb. and she was getting the Sempirica there also. It was marked on her passport. A dog with a passport!

FarPoint · June 25, 2020, 02:38 AM

Your new pooch is looking pretty happy in that shot. All settled in now, and responding to commands in English? IÃ¢â,¬â,,¢m going to look into the Simpirica you mentioned as an alternative. The ticks are getting worse here, and itÃ¢â,¬â,,¢s kinda gross extracting them. But they die with a satisfying popping sound when ya crush Ã¢â,¬Ëœem.
I was in a Ford V-10 powered motor home yesterday and saw the exact same heater controls.
So you were right about the Mustang.

Rickf1985 · June 25, 2020, 08:24 AM

It's Simparica. I was going to get a pic of the box but we used the last ones up last week and the new script isn't in yet.

And yea, Winnebago certainly did not care much for any brand loyalty, whatever they could get cheapest or was available at the time.

FarPoint · June 25, 2020, 12:14 PM

Just tried to respond to your PM - your inbox says full. But thanks for the photos and insight to the meds.
Re the vacuum lines - now I can see about tracking down a map for the lines but if Winnebagel was that mercenary about suppliers, and given the other stuff I've seen in this unit, I'm sure it's going to be me mapping out one line at a time.