How To Fix Your Trunk Vent Drains

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Otto Skorzeny
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How To Fix Your Trunk Vent Drains

Postby Otto Skorzeny » Sun Sep 04, 2016 9:55 am

Many of you have probably already figured out a hack to deal with GM's state of the art, Flow-Thru Ventilation system which allows air to flow through the cabin of the car and allows water to flow through the trunk and rust out your fender wells.

In case you haven't, here are some ideas that you may wish to try. I fixed my '66 yesterday. Sorry, I can't post photos because my camera broke.

Anyhoo, I considered several options from radiator hose, to flexible vacuum cleaner tubing, to plumbing the whole mess with PVC.

As it turned out, the cheapest way was also fairly easy and very close to stock appearance. Not that appearance matters because the major problem areas are hidden from view if you have the trunk upholstered with the cardboard panels blocking the wheel well.

My plastic tubes that connect the drain from the rear deck were in great shape so all I really had to worry about were the rubber tubes in the wheel wells that run between the plastic tubes and the outlet down in the wheel well.

I rummaged around the radiator hoses at the local Advance Auto store and found a hose with the correct inside diameter top mate with the metal outlet in the wheel well and the plastic drain tube. It had the right bends in it to do the job.

Upon further investigation, I discovered that the bends are a near perfect match to eliminate the GM plastic tubs all together. I kid you not. It works for both sides of the car and with just a little trim at each end. the radiator hose must be slightly bent at the bottom to connect to the wheel well opening but it doesn't flatten out. Since gallons and gallons of water won't be pouring through it it is a non- issue.

However, since my plastic drain tubes were in good shape, I considered cutting off the part with the bends for the wheel well and discarding the rest. After further consideration I decided to go a completely different route.

I purchased an extra large bicycle inner tube and used it to fill the space between the plastic tubes and the wheel well opening. Perfection!

I folded each end up on itself twice like I was making cuffs in a pair of blue jeans. This allowed a hose clamp to get a good grip without tearing the rubber. I did this on both ends. Don't use the original spring wire clamps. They aren't tight enough or easy enough to work with.

To install it, remove the plastic tube from the top first and then attach the inner tube. It's easier this way. Don't cut the tub to length yet.

Fish the end with the inner tube through the hole to the wheel well and reattach the plastic tube in position.

Position the inner tube and allow for two folds on the end to make a cuff (or turtle neck collar) of about 1 inch. Cut the tube with scissors, make your cuff and push it over the outlet in the wheel well and clamp it in place.

Dump a bucket of water in the hole by the trunk hinge and watch all the water come out the bottom of the car instead of filling up your wheel well or trunk.

I decided to use the inner tube method because the inner tube was $10 and was enough to do 2 Toronados. The radiator hose method would be ideal for someone whose plastic tubes are cracked, missing or disintegrated. They're more expensive, though at $25 each.

Here is the critical information:

Inner Tube Method: Specialized 26 x 2.3 / 3.0


Radiator Hose Method: CARQUEST / Dayco E72248


I hope this helps you guys. Oh ya, as an added bonus you might discover your missing spare tire mounting hook, wing nut and bracket assembly down in the wheel well like I did!

MNfirefighter
Posts: 17
Joined: Sun Jun 26, 2016 1:08 pm
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Years Owned: 1966 Toronado Deluxe - all original - white exterior w/ plum interior

Re: How To Fix Your Trunk Vent Drains

Postby MNfirefighter » Mon Oct 10, 2016 3:39 pm

Very Interesting info. Mine are in good condition but some good information to keep on the back burner.

Otto Skorzeny
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Joined: Fri Feb 28, 2014 12:41 pm
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Years Owned: 1966 Toronado

Re: How To Fix Your Trunk Vent Drains

Postby Otto Skorzeny » Mon Oct 10, 2016 6:11 pm

How are the rubber parts in the quarter panel wells?

Pour water into the vents with the trunk open and watch for leaks. Stick your hand down in the bottom and feel around. See if you pull out dirt or rust or anything else. Is it moist? I'd be amazed if the rubber parts in the quarters were not torn. The hard pipes that are visible when you open the trunk might be OK if the car had an easy life.

MNfirefighter
Posts: 17
Joined: Sun Jun 26, 2016 1:08 pm
TOA Membership Number: 1
Years Owned: 1966 Toronado Deluxe - all original - white exterior w/ plum interior

Re: How To Fix Your Trunk Vent Drains

Postby MNfirefighter » Tue Oct 11, 2016 7:00 pm

Mine are in good condition because I replaced them already :lol: I used new hose clamps to hold my new rubber sections to the hard plastic sections and can run the hose through vents and the water pours out under the rear wheel wells. I do still have a leak of water underneath the rear deck lid somewhere. Still getting water in the trunk. I need to remove the chrome around the rear window to can access to the screws not visible (to my understanding).

Otto Skorzeny
Posts: 1157
Joined: Fri Feb 28, 2014 12:41 pm
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Years Owned: 1966 Toronado

Re: How To Fix Your Trunk Vent Drains

Postby Otto Skorzeny » Wed Oct 12, 2016 5:13 am

Yep. It's leaking in around window - probably from top and bottom. The front and rear windows don't use rubber gaskets like most cars of this era. That makes removal easier but allows the goo used to seal them in and hold them in place to dry out, crack, etc. allowing water in.

This results in rust in the window channel which creates a pathway straight into the trunk.

What did you use to repair the rubber sections of the drains?

MNfirefighter
Posts: 17
Joined: Sun Jun 26, 2016 1:08 pm
TOA Membership Number: 1
Years Owned: 1966 Toronado Deluxe - all original - white exterior w/ plum interior

Re: How To Fix Your Trunk Vent Drains

Postby MNfirefighter » Sat Oct 29, 2016 5:28 pm

I bought oem replacements from Fusick.

simrek
Posts: 2
Joined: Mon May 22, 2017 8:22 am
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Years Owned: 1966 Gold / Black Toronado

Re: How To Fix Your Trunk Vent Drains

Postby simrek » Mon May 22, 2017 6:12 pm

I took his advice and went the heater hose route. The application right to left calls for the hoses to be a mirror image and the hoses are not, so one side will fit better that the other. I did have to do some modifications to the hoses to get them to fit just right. Also, I recovered my trunk and I think that the inner tube style connections would collapse under the weight of the trunk material. That might cause a narrowing of the tube, possibly cause a clog. Once you cover those trunk drain tubes, you have no idea what's going on under that material. It would only take a bunch of twigs or leaves to get down there and cause a back-up if the tube gets flattened in any way. The hoses will keep their shape and thus maximize the flow in a downpour and they will never dry out and crack like the OEM inner tube style ones will. They actually gave the trunk material a nice shape to cover.


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