Wiper delay not working, how to solve?

PepijnWK

Active Member
#1
Reading the excellent topic: revitalised Wiper DelayI got the idea of fixing my wiper delay that does not work. I followed al the steps put new grease in etc etc. Dismantled the relay governer and when pressed while holding the thumb on the vacuum outlet it takes more than 5 seconds for the "piston: to come back. At first this was returning immediately but after adding some foam this iumproved massively.

But stil the wiper relay does not work. When I put the switch to delay niotrhin happened!
So I checked the electrics and the wires were wrongly attached!!!

got this sorted according this picture:



and the wipers work in de delay position but there is no delay!!!


So I took out my steering wheel and tried to free the vacuumhose to see if there were any imperfections.



What I see now is that when I switch to delay and I suck at the vacuum tube the delay is there until I relase the vacuum. The the wipers go until I suck again( apply vacuum). So the system works but there is no initial vacuum nor is it created.

What could the culprit be? is it the foam not being enough or is it the missing spring I unlfortunately lost that really has to be present?
Or is it something else that causes this?


thanks in advance for your answers!
 

PepijnWK

Active Member
#2
The spring is not the problem. The vacuum is not there and therefore the piston is moving out to quickly so activating the movement of wipers. The spring is helping this activation. So it has to do with holding the vacuum.
 

GRTV8

Well-Known Member
#3
suck on the steering wheel end of the plastic tube with the wipers on delay.
You should feel a vacuum against your tongue .
If you have a split in the plastic tube it wont work
 

PepijnWK

Active Member
#4
suck on the steering wheel end of the plastic tube with the wipers on delay.
You should feel a vacuum against your tongue .
If you have a split in the plastic tube it wont work
Thanks for your post
When I suck and hold my tongue against the pipe the vacuum holds indeed. but only after I sucked it. If I do not suck it and just hold my tongue against it .

I think there is a leak somewhere in the vauumline either at one of the ends or somerwhere in the plastic tube.
 

jp928

Well-Known Member
#7
I note that the 1977 parts book shows on 14-32 the delay unit as 573034 for RHD (tagged a early models), 573035 LHD, and then 14-34 (no page 14-33) as 573035 , no reference to RHD or LHD.
??
 

PepijnWK

Active Member
#8
I note that the 1977 parts book shows on 14-32 the delay unit as 573034 for RHD (tagged a early models), 573035 LHD, and then 14-34 (no page 14-33) as 573035 , no reference to RHD or LHD.
??
I saw the same thing. Mine is a 1976 lefthand drive so definitely a 573035. I do not know what the changes are. It couyld be that later on they did not use different units for righthand drive or lefthand drive. In the beginning they probably did or that the bracket is just little different.
 

PepijnWK

Active Member
#9
well it continues:
The hose is not leaking it preserves pretty well the vacuum when I hold my tongue against it.
The culprit is the adjustable airvalve:



is there a way to service these?
 

clive P62

Active Member
#10
Not really had a issue with the pipe ( only one car with a split on the capsule )in my case it's the vacuum capsules which needed repair.
 

cobraboy

Well-Known Member
#11
If you extend the upper end of the pipe with joiner part number 3942789, then add precisely 24 7/8" of pipe this will reach your driving position ( mid way seat travel, 1/2 rake of seat. You may then control the delay by placing your tongue over pipe end and varying frequency of wipe by alternating between nipping with teeth and tongue.

HTH
 

harveyp6

Well-Known Member
#12
I saw the same thing. Mine is a 1976 lefthand drive so definitely a 573035. I do not know what the changes are. It couyld be that later on they did not use different units for righthand drive or lefthand drive.
Do I remember that some really late cars had an electronic delay unit, or did I dream that?
 

clive P62

Active Member
#13
Apparently so Harvey but I've never seen any.
I broke up a very late R reg Brazilia brown VIP some years ago and that didn't have a electric delay wiper system.
 

jp928

Well-Known Member
#15
My delay unit had its hose nipple broken off. I drilled the body and superglued a short piece of ~1/8 OD brass tubing in, which I hoped would work. Had a problem getting the hardened hose onto the tube. Then had an issue with the valve under the little metal plate not doing its job as I thought it should. In the end, to get some delay, I plugged the brass tube, and now I get a delay of ~5 secs just due to the valve leakage. I have one of the VW programmable relays that modern cars use, so I will try that when I can work out how to connect it.......
 

PepijnWK

Active Member
#16
If you extend the upper end of the pipe with joiner part number 3942789, then add precisely 24 7/8" of pipe this will reach your driving position ( mid way seat travel, 1/2 rake of seat. You may then control the delay by placing your tongue over pipe end and varying frequency of wipe by alternating between nipping with teeth and tongue.

HTH
yes great idea!! pointing out the real relevance of this problem................( it is really a minor problem in the end, but hey it used to work some 45 years ago so i would like to make it work again)
 

jp928

Well-Known Member
#19
When I tried to fix my wiper delay unit I found it hard to get the right size rubber/foam behind the clip to control the valve, so that pushing the rod would blow air out, but seal when the spring tried to push the rod out. Just got a genuine NOS unit, and it leaked as delivered. On removing the metal clip, the black foam in there disintegrated. I cut a new piece of foam, BUT i also smeared the inner face of the valve disc with vaseline - now it holds vacuum fine. With the bleed nipple blocked there was some resistance to pushing the rod, so I thinned the foam a bit. The new unit came with a different orientation on the bracket, so I had to rotate it some - holes already available. To make it easier to install I cut slots from the mounting holes to the end, so I could have the screws started, and slide the bracket in - all back now. The reason my origoinal had its bleed nipple broken off appears to be the original black tube is as hard as, so I fitted a few inches of thick wall rubber vacuum tubing as a bridge to the nipple. Should all work now, as long as the tube to the adjuster is OK, and the adjuster doesnt leak. Tests for another day.
 
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