Spitfire Water Leakage Paths - Spitfire

[dklawson]

I've been working on our project Spitfire's floors. I'm 3/4 of the way through the floor so it's much easier to find water after a rain storm. Convertible top leaks are obvious but I've got some "up front" leaks and a boot leak I'm trying to sort out.

The boot seal is new and the luggage rack seals are intact. The tail lamps have been replaced/repaired with new plastic to metal seals. Only the metal to car body seals have not been replaced. However, I have put a thin strip of closed cell foam gasket tape around the back of the suspect lamp just in case. All the grommets into the boot are intact. Visual examination after a rain shows some witness marks that appear to be water tracks from just above the right bumper mount and/or the body seam above the bumper mount. Any comments or suggestions about leaks from these areas?

Lying on my back under the dash gave me some curious observations about the front leaks. I saw water dripping off a ventilation hose and this MAY have come from one of the wiper wheel boxes. On the other side of the car, I saw water dripping off the backside of the heater where the foam gasket for the heater hoses contacts the bulkhead. On that same side I noticed that the inside of the door hinge pillar was wet. The door check straps have no seals. Is it possible that water running down the front edge of the door could be driven into the door hing pillar without that seal being present?

If you've seen leaks from such places please let me know what you did. I'd like to fix the leaks but if what I'm observing doesn't make sense or working on them would be a waste of time I'd like a heads up from those more experienced with this than I am. Thank you for the suggestions.

 

[guzzul]

I can't add much on the rear leak, but have a couple of thoughts about the front.

Lying on my back under the dash... I saw water dripping off a ventilation hose and this MAY have come from one of the wiper wheel boxes.

I have had this problem. I corrected it by undoing the wheel boxes and replacing the wheelbox rubber top-seals (with some black silicon on the bottom) and re-installing. There wasn't a lot of water getting in, just enough to see drips after a heavy rain or after washing the car.

On the other side of the car, I saw water dripping off the backside of the heater where the foam gasket for the heater hoses contacts the bulkhead.

This may be water running off the scuttle and back down the heater pipe. Water flows down through the slots in the back center of the bonnet and then down that lattice grate in the body underneath the bonnet. It is supposed to flow down a drain box and out through a little flap on the front of the firewall onto the scuttle. Since the scuttle is pretty flat, water can just sit there, and I think it can easily just flow back into the holes where the heater pipes come through. Try cutting a piece of 1/2" pipe-foam insulation and wrapping it around the heater-pipes to make sure these holes are sealed and don't let water. I don't think you can get the original gaskets for these any more.

On that same side I noticed that the inside of the door hinge pillar was wet. The door check straps have no seals. Is it possible that water running down the front edge of the door could be driven into the door hinge pillar without that seal being present?

Yes, I would think so. With no seal, there's nothing to stop the water from flowing along the top of the check strap into the door pillar and down. Did you notice the pillar *below* the check strap was wet, or above the check strap? If there is water in the door pillar above the check strap I would suspect a leak around the windscreen seal flowing down the inside of the car into the pillar.

 

[dklawson]

Thank you for the excellent advice. The pipe insulation sounds like a brilliant substitute for the NLA heater pipe seals.

I checked the wheelboxes and found no gaskets at all under the chrome plinth/bezels. I'll make some gaskets from thin gasket paper or similar and apply a sealant as you suggested.

The water I noticed in the pillar was below the check strap. If it rains again tomorrow I'll take a look higher up to see if the windscreen seal is contributing to the front footwell leak.

Thanks again!

 

[skucera]

I'll confirm Ross's advice. I had an annoying leak under my dashboard where water was dripping down the wiring for my wiper switch, and down the speedo cable. It was caused by leaky wiper shaft seals, and fixed by new neoprene seals. I've also had a little leakage around the holes in the firewall for the heater pipes. I bodged my with a little duct tape, but the pipe wrap idea sounds like a much better fix.

Scott

 

[Scott_Hower]

I bodged my with a little duct tape, but the pipe wrap idea sounds like a much better fix.

Scott

I like 3M Strip Caulk; works well too.

 

[waltesefalcon]

Put holes in your floors for drains, then you don't have to worry about the leaks anymore.

 

[dklawson]

I am adding additional drain holes but was planning on putting plugs in them. Are you suggesting that it's OK to leave the drain holes "open"?

 

[guzzul]

I'll make some gaskets from thin gasket paper or similar and apply a sealant as you suggested.

Doug - these should be rubber or neoprene as skucera suggests. Maybe thin gasket cork would work too. Shouldn't be too thick, but something waterproof and a little squishy so you can tighten down the bezel a bit (not too much). Also check under your windscreen washer jets, there should be small gaskets under them too.

 

[dklawson]

OK then, rubber it is. I'll look for other damaged and missing seals. The windshield will be replaced later so I may "band-aid" any issues there until I'm ready to fit new glass.

Thanks all.

 

[dklawson]

I may start a second thread on this but last night I discovered a previously unknown and substantial leak.

Last night I removed more of the interior of the car, primarily the carpet behind the seats. The horizontal shelf behind the seats was full of water giving the carpet that wonderful odor. I know leaks in this area must be attributed in large part to the convertible top, but... since there aren't holes in the top, what should I be looking for as a path for all this water? Between the left and right sides of the car I'd say there was literally between 1 to 2 cups sitting on the shelf after I took the wet carpet away.

 

[waltesefalcon]

Check around your fille tube, the gasket between the body and it may be leaking which would dump alot of water onto both the shelf and your trunk.

 

[dklawson]

The boot leaks I have do not put any water on the spare tire shelf. Perhaps the water is all finding a way down the other side of the fuel tank. I'll check the tank seal to see.

Perhaps when Hurricane Hannah's rains come our way I'll sit in the car for a while with a flashlight and watch to see where the water is coming in.

 

[vagt6]

Doug, I feel your pain on water leaks. On Spits (and also GT6s) water is likely to come in at practically any area that has a rubber gasket, grommet, etc. where the rubber is not in very good condtion and installed correctly.

In fact, I'm not sure I've ever seen a Spit that would not leak if driven in the rain. You just have to check the obvious water paths, maybe test by pouring a bit of water on them and watching for leaks.

My '70 GT6 drove me nuts on this. Finally, after very carefully checking all the rubber grommets in the firewall, I found my problem. Water was leaking in through the main harness where it passes from the engine thru the firewall. I replaced the grommets, sealed them off with a little rubber cement, and it cured the problem.

I'll be very interested to learn what the source(s) of your leak(s) are. Please keep us posted.

-- Mark, with wet feet.

 

[dklawson]

Thanks for the sympathy Mark. Fortunately our GT6 doesn't appear to leak but then again, it doesn't have near the number of body openings (and old seals) that the Spitfire does. It also lives under a nearly water proof car cover.

When I got home I took two steps. I looked at the tank filler neck seal. It's hard as a rock, curling, cracking, and lifting off the car. I'm sure some of the leakage into the 'back seat' is from there. As a stopgap measure until I get a new seal I have wrapped the seal's flange with very soft closed cell foam tape and stuffed it into the gaps. Hopefully that will stem the tide until I have new parts.

Earlier in this thread the suggestion was made to use foam pipe insulation to replace the suspect heater core pipe to bulkhead seals. It occurred to me that this would also make a good temporary seal for the missing door check-strap seals. I have put some pieces of foam insulation in place on both doors... again, only until I can get the real parts.

We are expecting rain for the next several days. Hopefully these band-aids will reduce the amount of water getting into the car. I'll let you know next week. Thanks again to everyone for the suggestions.

 

[dklawson]

Tropical storm Hanna dropped about 5" of rain on us overnight. I checked the Spitfire out once the sun came back out.

The shelf behind the seats was full of water again. Witness marks indicated that the water was dripping down from the convertible top, not down through the tank/body seal.

The passenger footwell was almost dry. The rusty area that was the drivers footwell was very wet. The horizontal bulkhead in the engine compartment was covered in water. So, what I've learned is the door check strap seals are important and I must replace them. The wheelbox seals are probably contributing more to leaks than I want to admit and I need to work on them, and the heater core hose feed-throughs need some attention. The tank seal is no good, but probably not critical to solving my leak issues. And... the convertible top I thought was serviceable for another season needs a close examination. Perhaps with some vinyl sealant I can still get through a year more with it.

 

[RonMacPherson]

FYI, for leakage a good tool to acquire is down at your friendly Pharmacy.. Get a spray bottle of Tinactin, or some other like it. The powder sprayed dries and when something leaks it leaves a trail on the sprayed powder. And when you get the leak fixed clean up is just a cloth wipe away.

 

[dklawson]

That's a very clever idea. Thanks for the suggestion!