Rear Deck Vent Drains Clogged
Thread Starter
Racer
Joined: Dec 2004
Posts: 402
Likes: 2
From: Los Angeles
Rear Deck Vent Drains Clogged
I've been trying to clear the drain holes on the rear plenum vents using a clothes hanger with no success. Water continues to spill into the rear compartment of my 70' vert.
1. Will I have better luck clearing the vents by going underneath the car?
2. Is there clear access to the drains or will I have to remove my spare tire carrier / other items?
3. Any chance shooting compressed air down each drain hole may free the obstructions?
Looking for options.
Thanks for your help.
James1970
1. Will I have better luck clearing the vents by going underneath the car?
2. Is there clear access to the drains or will I have to remove my spare tire carrier / other items?
3. Any chance shooting compressed air down each drain hole may free the obstructions?
Looking for options.
Thanks for your help.
James1970
Race Director
Joined: Sep 1999
Posts: 11,361
Likes: 383
From: Plano TX
AC or not? It makes a difference. On my '71 w/ AC there are vent drain hoses that connect to the plenum on one end and the other end dumps water out the wheel well. If this hose is cracked water will leak into the cargo area. I think it may work differently without AC.
Le Mans Master
Joined: Jun 2002
Posts: 8,339
Likes: 24
From: I can walk to MA
What makes you believe it is clogged ? Does the grill area actually fill up ?
I think drain hoses need replacing. Look up above the rear window storage
tray area to see the hoses leading to the wheel wells.
Most are cracked by this time - if original. Coat hanger will make it worse.
They need to be drilled out (pop rivets) and riveted back in ... simple.
I think drain hoses need replacing. Look up above the rear window storage
tray area to see the hoses leading to the wheel wells.
Most are cracked by this time - if original. Coat hanger will make it worse.
They need to be drilled out (pop rivets) and riveted back in ... simple.
Race Director
Joined: Apr 1999
Posts: 10,867
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From: Beverly Hills/Pine Ridge Florida
Originally Posted by James1970
I've been trying to clear the drain holes on the rear plenum vents using a clothes hanger with no success. Water continues to spill into the rear compartment of my 70' vert.
1. Will I have better luck clearing the vents by going underneath the car?
2. Is there clear access to the drains or will I have to remove my spare tire carrier / other items?
3. Any chance shooting compressed air down each drain hole may free the obstructions?
Looking for options.
Thanks for your help.
James1970
1. Will I have better luck clearing the vents by going underneath the car?
2. Is there clear access to the drains or will I have to remove my spare tire carrier / other items?
3. Any chance shooting compressed air down each drain hole may free the obstructions?
Looking for options.
Thanks for your help.
James1970
With the heat control "off", those plenium vents should be closed tight. If they're not, that could be the source of the massive water leak.
AC cars have plates over the flapper area. They're not funcional in AC cars. Chuck
Race Director
Joined: Apr 1999
Posts: 15,156
Likes: 477
From: NM
Originally Posted by James1970
Zwede:
70' Vert., L-46 w/no AC.
Appreciate you assistance.
James
70' Vert., L-46 w/no AC.
Appreciate you assistance.
James
Originally Posted by LittleJake
The rear grills in the back of the deck lid near the convertible top? Mine go straigth to the ground???? Is there supposed to be a tray with a hose going from it?
Talk about a loss of luggage space 
Not sure if this happened with the '71 model or the '72 model.
tom...
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Thread Starter
Racer
Joined: Dec 2004
Posts: 402
Likes: 2
From: Los Angeles
Originally Posted by Tom73
James, in 70 the vents are located over the interior stowage area. There should be rubber tubes leading from them to the wheel wells for drainage. Bet the rubber tubes are rotted out. Should be able to access from inside the car.
In later model convertibles they shortened up the stowage area and the vents ended up being behind the bulkhead, so on a/c cars, they are open to the ground since they do nothing other than looks. In the following pics the first is a 70 Vert and the second is a 73 Vert. As you can see, the rear bulkhead has been moved forward about 4 inches Talk about a loss of luggage space Not sure if this happened with the '71 model or the '72 model.
tom...
In later model convertibles they shortened up the stowage area and the vents ended up being behind the bulkhead, so on a/c cars, they are open to the ground since they do nothing other than looks. In the following pics the first is a 70 Vert and the second is a 73 Vert. As you can see, the rear bulkhead has been moved forward about 4 inches
Talk about a loss of luggage space Not sure if this happened with the '71 model or the '72 model.tom...
The photo on the left reflects my 70'.
It's my understanding that water enters through the top vents and drains to the interior tray (just behind the Astro / Plenum vents doors) where it exists through rubber hoses on the left and right. From there the water drains out of that round metal disc shown at lower left in the left photo.
The two rubber hoses are not the problem. Water collects in the interior tray and spills over into the rear storage compartment. Therefore, I believe the problem is between the rubber hoses and the metal disc shown in the left photo.
Question:
Is the metal disc assessable/removable for cleaning?
Thanks for your help.
James
Thread Starter
Racer
Joined: Dec 2004
Posts: 402
Likes: 2
From: Los Angeles
Originally Posted by Chuck Gongloff
Are you sure it's the drain holes? On a non AC car, you have air flappers, which are part of the Astro Ventillation system. Are you air flappers closed? Is the rubber/foam on them deteoriorated to the point that they won't seal, allowing water to leak?
With the heat control "off", those plenium vents should be closed tight. If they're not, that could be the source of the massive water leak.
AC cars have plates over the flapper area. They're not funcional in AC cars. Chuck
With the heat control "off", those plenium vents should be closed tight. If they're not, that could be the source of the massive water leak.
AC cars have plates over the flapper area. They're not funcional in AC cars. Chuck
Hi Chuck:
I've refurbished the rear pleanum vent door mechanisms/seals and that's not the problem. Water will enter the rear interior tray regardless if the doors are shut.
My issue is that water is collecting in the interior tray and not draining out the two rubber hoses to the ground.
I appreciate you input.
Best,
James
Le Mans Master
Joined: Jun 2002
Posts: 8,339
Likes: 24
From: I can walk to MA
The drain hose retainers (metal thingy) are held with three pop rivets.
To remove, the (luckily aluminum) pop rivets must be drilled out.
For a coupe, this is best done from the interior. Dunno about space in
the vert for a drill. Reattach with similar pop rivets or small stainless screws/nuts.
This piece only holds the flanged end of the rubber drain hose in place.
Check out section (UPC) 1 - sheet F22 - in the 1970 AIM.
I'd think that: If clogged at the retainers, you could use tweezers,
needlenose pliers, or even a bent coathanger to pick the crap outta there.
Be careful with those hoses.
To remove, the (luckily aluminum) pop rivets must be drilled out.
For a coupe, this is best done from the interior. Dunno about space in
the vert for a drill. Reattach with similar pop rivets or small stainless screws/nuts.
This piece only holds the flanged end of the rubber drain hose in place.
Check out section (UPC) 1 - sheet F22 - in the 1970 AIM.
I'd think that: If clogged at the retainers, you could use tweezers,
needlenose pliers, or even a bent coathanger to pick the crap outta there.
Be careful with those hoses.
Last edited by NHvette; Apr 12, 2006 at 05:34 PM.
Thread Starter
Racer
Joined: Dec 2004
Posts: 402
Likes: 2
From: Los Angeles
Originally Posted by NHvette
The drain hose retainers (metal thingy) are held with three pop rivets.
To remove, the (luckily aluminum) pop rivets must be drilled out.
For a coupe, this is best done from the interior. Dunno about space in
the vert for a drill. Reattach with similar pop rivets or small stainless screws/nuts.
This piece only holds the flanged end of the rubber drain hose in place.
Check out section (UPC) 1 - sheet F22 - in the 1970 AIM.
I'd think that: If clogged at the retainers, you could use tweezers,
needlenose pliers, or even a bent coathanger to pick the crap outta there.
Be careful with those hoses.
To remove, the (luckily aluminum) pop rivets must be drilled out.
For a coupe, this is best done from the interior. Dunno about space in
the vert for a drill. Reattach with similar pop rivets or small stainless screws/nuts.
This piece only holds the flanged end of the rubber drain hose in place.
Check out section (UPC) 1 - sheet F22 - in the 1970 AIM.
I'd think that: If clogged at the retainers, you could use tweezers,
needlenose pliers, or even a bent coathanger to pick the crap outta there.
Be careful with those hoses.
Thank you for your input. Do you know if the tire carrier needs to be removed to access the drain hole retainer? I can't see it at present and am guessing the car will need to be jacked for access.
Race Director
Joined: Apr 1999
Posts: 15,156
Likes: 477
From: NM
Originally Posted by James1970
Thank you for your input. Do you know if the tire carrier needs to be removed to access the drain hole retainer? I can't see it at present and am guessing the car will need to be jacked for access.
).You may want to drop the carrier (only a few bolts and it falls out) and take a look to see what it would take for you to tackle it.
tom...
Last edited by Tom73; Apr 13, 2006 at 06:26 PM.
Le Mans Master
Joined: Jun 2002
Posts: 8,339
Likes: 24
From: I can walk to MA
If you can get the grills off, then try sucking them out with a shopvac.
If that doesn't work, try locating the hoses inside and squeeze them
to try and loosen the clog and vacuum again.
Hopefully, you don't have to move the tank ... and good luck with the
tire carrier. I had to cut one of my hanger bolts to remove.
Sorry - all my experience here is with a coupe ... where the hoses drain into the rear wheel wells.
I'm learning from your troubles. Good Luck
If that doesn't work, try locating the hoses inside and squeeze them
to try and loosen the clog and vacuum again.
Hopefully, you don't have to move the tank ... and good luck with the
tire carrier. I had to cut one of my hanger bolts to remove.
Sorry - all my experience here is with a coupe ... where the hoses drain into the rear wheel wells.
I'm learning from your troubles. Good Luck
Thread Starter
Racer
Joined: Dec 2004
Posts: 402
Likes: 2
From: Los Angeles
Originally Posted by NHvette
If you can get the grills off, then try sucking them out with a shopvac.
If that doesn't work, try locating the hoses inside and squeeze them
to try and loosen the clog and vacuum again.
Hopefully, you don't have to move the tank ... and good luck with the
tire carrier. I had to cut one of my hanger bolts to remove.
Sorry - all my experience here is with a coupe ... where the hoses drain into the rear wheel wells.
I'm learning from your troubles. Good Luck
If that doesn't work, try locating the hoses inside and squeeze them
to try and loosen the clog and vacuum again.
Hopefully, you don't have to move the tank ... and good luck with the
tire carrier. I had to cut one of my hanger bolts to remove.
Sorry - all my experience here is with a coupe ... where the hoses drain into the rear wheel wells.
I'm learning from your troubles. Good Luck
No apologies necessary NHvette. You've been a great help.
Just to follow-up: If I recall correctly, on the 70' convertable water enters the top vents and drains to a "trough" directly behind the plenum vent doors. It is here where water is collecting and spilling over into the interior of the car.
I'm going to concentrate my efforts on making sure the two rubber hoses that drain from the "trough" to the metal disc retainers are clear. Don't want to drop the tank. There's got to be an easier way.
I'll revisit this topic later and let you all know how I made out.
Happy Easter to everyone.
Best,
James
