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Thanks for that info Jim. I am trying to figure where the weak link is on the 55-6. You say you are running a fuel/vac pump not the oil pump vac combo? Is this a better system than the 55 set up? Do you have the balance valve? Not sure what the 54 has stock. Where is your resevoir plummed in?
Has anyone had a balance valve as used on the 55 apart or a known good part and a test procedure? does a 54 have the can-o-matic to sweep past the curves?

Packard only used the oil pump vacuum booster and balance valve on the V8s. The only stock vacuum reservoir Packard supplied was for the power brakes and the way it is plumbed and location of check valve, doubtful it would be of much use on wipers -- although if engine is running and there is adequate vacuum to keep the check valve open it might have a slight effect. That would depend on where the wiper source is taken from. If on a shared fitting, maybe. If from a separate port on manifold, doubtful. Once vacuum lowers and check valve closes, the reservoir is isolated from the manifold and wipers. The windshield on pre 55 cars is relatively flat so no need for the cam-o-matic

Interesting to note the shape of the windshields on pre 55 cars. This is a major difference as I noted above, upon manually sweeping the blades on a 55 with the motor removed the only place there is resistance is just past the very end of the stroke when the blades have made that sweep around the curved area near the A pillars, have reversed their motion and are returning back. The resistance at this point is considerable compared to the other 95% of the motion. This may be one reason why there are issues. The motors will have to be in tip top shape. The vacuum system in the Clipper is stock so I agree the canister for the brakes will have no effect IF the check valve at the carb base is working. I have eliminated this though- when I had the modern carb and adpt plate on the car I had plumbed in a modern booster vacuum check valve and there was no change,
I think there is a problem with this balance valve. I would also like to know -what should I see from a functioning oil pump mounted vacuum pump? At idle what inches? at 1000rpm? at 1500? The car is put up for now so it may be a while till I can make checks.
Still no one has offered any info on the balance valve. Any body had one apart? anyone test a known good one? Will both inlets test the same, isolating from the outlets if at zero vacuum?

I guess I should review the plumbing.

On my 54 the reservoir is back under the fender (driver side under the hood).

As I have never traced the hoses I guess I better look things over.

The vacuum booster pump is part of the fuel pump.

My car does have power brakes.

I don't recall exactly the source of vacuum for the wipers, somewhere on the manifold I thought. I Tee'd into the wiper source to run the washer, dressing the rubber tubing as I saw in service info I believe I got that on this site.

I don't know about check valves, I guess I should see if the service manual has a vacuum flow diagram.

It all seems to work just fine however.

I don't want brake failure.

Jim

Well, I will say if you have the power brakes and you dont know the condition of the 11/32 hoses feeding it- you should inspect. As noted by Howard, There are NO barbs on even a swaged buldge on the nipples at the canister or T etc and I was quite surprised to see this. The hoses get hard and the clamps will be useless

Don't believe you will find a comprehensive diagram in any of the SMs -- at least I don't recall ever seeing one. They might publish bits and pieces with install instructions on how best to tie an accessory in but vacuum is probably one of those things Packard figured all the mechanics could figure out.

On the 54 there should be a large nipple and tee affair on manifold near the base of carb. The check valve is screwed into that fitting and has a nipple for a 11/32 or 3/8 hose. The hose should go rearward and then across firewall to just above brake booster where it tees. One leg drops down to the booster and other leg continues on to reservoir. Once the check valve closes, that circuit is cut off from manifold vacuum.

On some of the cars, the vacuum source for wipers also starts at the same fitting on manifold near carb. On others it has a separate fitting on manifold or on carb. From either source it then goes to upper section of fuel pump, out pump and back to firewall where it connects via a short hose to wipers and washers. If a car had the optional rear window wiper, its vacuum source was also tee'd off the short hose supplying the front wiper.

Great info! As I said before there are some experts here that are encyclopedia's of knowledge- Howard,O D, And others.
Anyone test the balance valve? any specs on the vac side of the oil pump? Or the fuel pump mounted vac pump for that matter.

one thing of note. The trico used on the 55 is a larger case-slightly deeper with a larger paddle compared to this earlier unit. Was this for the increased sweep of the cam-o-matic or for greater leverage due to the increased friction? anyone know how many sizes of motors trico made?

This is a 55 Clipper Custom so no fuel pump vac assist. The brake hoses are as you say but the vacuum assist is the oil pump lower section and a manifold source also to the balance valve. I was asking about specific vac #s on a properly functioning pump at a few rpms and also testing a known good balance valve. I see one for sale at Borth auto. How would I know it is good prior to purchase? I had also inquired about its proper finish and originality. No one has offered any suggestions. See the pic from borth. Seems the same gold hue clearly on the nipples where the hoses covered for 60 yrs.


http://www.borthautoparts.com/images/cars/packard/1955%20Packard%20Clipper%204Dr%20Custom%205562%20Parts/1955%20Packard%20Clipper%20Sprayer%20Washer%20Split%20No.88237-1.JPG