Front wiper arm travel

[M47Rman]

Hi all
I fitted new wiper blades to our 75 today, as the drivers side blade was smearing badly. I obtained a set of Bosch arms, of the correct specification, and complete with spoiler on the drivers side. However during fitting I noticed that each blade was approximately 5 to 10 mm longer than the old ones. After fitting I then tested the wipers, and lo and behold the drivers side wiper was contacting the windsreen surround, when it reached the end of its travel, in the vertical position. This I initially assumed to be due to the increased length of the new blades, but upon closer inspection, just below the point on the screen surround where the new blade is making contact, where two nicks in the rubber/plastic, where the OLD blades had previously been making contact.
When in the park position, the wipers are perfectly parallel with the base of the windscreen, and so are not obviously out of alignment.
I was going to remove the arm, and try to refit it in a slightly lower position, to try and prevent the wiper contacting the screen surround, but having removed the nut cover for the wiper arm, I could see no obvious spline or keyway.
So to the questions
Has anyone else had/ or has a problem with the wipers contacting the windscreen surround when in the vertical position?
How is the wiper arm located on the wiper hub, is it a spline or a keyway?
Is there any form of travel adjustment in the system, to reduce the length of the wiper sweep (arc)?
I have looked at my w/shop manual CD, and the section on the wiper system is very poor.
Anyone got any thoughts?
Andy

[biggles]

Originally Posted by M47Rman

Hi all
I fitted new wiper blades to our 75 today, as the drivers side blade was smearing badly. I obtained a set of Bosch arms, of the correct specification, and complete with spoiler on the drivers side. However during fitting I noticed that each blade was approximately 5 to 10 mm longer than the old ones. After fitting I then tested the wipers, and lo and behold the drivers side wiper was contacting the windsreen surround, when it reached the end of its travel, in the vertical position. This I initially assumed to be due to the increased length of the new blades, but upon closer inspection, just below the point on the screen surround where the new blade is making contact, where two nicks in the rubber/plastic, where the OLD blades had previously been making contact.
When in the park position, the wipers are perfectly parallel with the base of the windscreen, and so are not obviously out of alignment.
I was going to remove the arm, and try to refit it in a slightly lower position, to try and prevent the wiper contacting the screen surround, but having removed the nut cover for the wiper arm, I could see no obvious spline or keyway.
So to the questions
Has anyone else had/ or has a problem with the wipers contacting the windscreen surround when in the vertical position?
How is the wiper arm located on the wiper hub, is it a spline or a keyway?
Is there any form of travel adjustment in the system, to reduce the length of the wiper sweep (arc)?
I have looked at my w/shop manual CD, and the section on the wiper system is very poor.
Anyone got any thoughts?
Andy

I had the same problem after having removed the wiper arms to remove the plenum cover. The wiper arms are fastened to the hubs via conical friction locks - no splines or keyways. Just pry off the plastic cover over the nut, undo it, wiggle the arm off, adjust, fasten, done. This assumes of course that you have room for adjustment at the other end of the wiper travel.

/Erik

[M47Rman]

Originally Posted by biggles

I had the same problem after having removed the wiper arms to remove the plenum cover. The wiper arms are fastened to the hubs via conical friction locks - no splines or keyways. Just pry off the plastic cover over the nut, undo it, wiggle the arm off, adjust, fasten, done. This assumes of course that you have room for adjustment at the other end of the wiper travel.

/Erik

Thanks for the info Erik. I think I have got some room for adjustment, so will have a play later. Will let you know how I get on.
Andy

[Keith]

The conical washer under the nut is splined so you have lots of scope for adjustment

The wipers on all three of my cars just touch the screen surround but only just,no marks, I think the arm at rest may look a bit odd if adjusted too low to avoid them hitting

If you havent taken the arms off before how do you check you plenum drain?

[GreyGhost]

Originally Posted by Keith

If you havent taken the arms off before how do you check you plenum drain?

There is no necessity to remove wiper arms to check plenum drains, just the three scuttle clips. It is in fact only necessary to remove 2 scuttle clips but the third tends to release itself.

[M47Rman]

Originally Posted by Grey Ghost

There is no necessity to remove wiper arms to check plenum drains, just the three scuttle clips. It is in fact only necessary to remove 2 scuttle clips but the third tends to release itself.

Exactly why I am now missing one clip (the third one)! Once the three clips have been removed there is sufficient clearance to slide the tray (above the ECU) out from underneath the plennum cover. This then gives sufficient access to change the pollen filter and check the drains!
I have now removed one wiper arm, the drivers side, and have managed to refit it slightly lower, so that the blade no longer contacts the screen surround - mostly! There is no contact with the wipers on intermittent speeds, or speed one, but if I put them on full blast, there is a small amount of contact. Although I do not think there is now enough contact to mark the screen surround, so job done!:lol:
Andy

[GreyGhost]

Originally Posted by M47Rman

Exactly why I am now missing one clip (the third one)! Once the three clips have been removed there is sufficient clearance to slide the tray (above the ECU) out from underneath the plennum cover. This then gives sufficient access to change the pollen filter and check the drains!
I have now removed one wiper arm, the drivers side, and have managed to refit it slightly lower, so that the blade no longer contacts the screen surround - mostly! There is no contact with the wipers on intermittent speeds, or speed one, but if I put them on full blast, there is a small amount of contact. Although I do not think there is now enough contact to mark the screen surround, so job done!:lol:
Andy

EYC101470PMA Clip - Black - windscreen scuttle panel (those 7 under windscreen scuttle panel clips we always lose -) )

[biggles]

Originally Posted by Keith

The conical washer under the nut is splined so you have lots of scope for adjustment

The wipers on all three of my cars just touch the screen surround but only just,no marks, I think the arm at rest may look a bit odd if adjusted too low to avoid them hitting

If you havent taken the arms off before how do you check you plenum drain?

One thing I realized after having a feel at the screen surround with wipers on and driving a bit faster (110 km/h) is that the wind forces the blades further out than when stationary.