Soggy Footwell (Air Con drained blocked) Sorted!

[superdavelotus]

Hi all,

 

 

I've recently have been having problems with my 2009 Evora when vacuuming the footwell mats. They were completely soaked. When I lifted them out the foot was in a pool of water. I began to read this forum and also saw some other bits on other forums and started to read about the common caused etc.

So the next day I checked the door seals and found that my driver's door seal was tucked in at the rear where it shouldn't be, so I pulled it out. There was also the passenger side seal that was quite sealing right, so I corrected that. I was still baffled as I don't power wash the car and it used to liver under my car port until recently when I inherited a Mini Cooper which I was working on under the carport.

 

So here's where it get interesting, the night before last, I took the fuse box cover off in the passenger side footwell. By chance, I had my torch shining to right hand upper side of front bay wall and could see a tunnel into the HVAC system. When I turned on the fan along with the air con, I could see lots of water flushing about in the tunnel. I soon realised that this was the cause of my problem, a blocked drain tube/hole or something.

I rang Oakmere Lotus yesterday afternoon but they couldn't look at it that day and said that they don't work the weekend, so it would be next week sometime. I know Paul in service a fairly well and he told me that they modify the system by removing the plastic pipes and rubber tubes. He also pointed in the direction that I have to access this from removing the front undertray. This task proved difficult for me as I don't have access to ramps/ lift.

 

So this morning, I came up with a plan. I parked my car on the road outside with half the car on the pavement and other side on road. Then I jacked up the roadside of the car and I could now access the undertray.

There are 18 bolts to remove, sounds a lot but they come off in less than 10 minutes. I started at bumper end and all the bolts to bumper, I simply loosened NOT REMOVE. The two end ones do have to be removed.

There are 4No. in the middle towards the rear, these are longer than all the others due to the spacers between the undertray and the car body.

Then there are 6No. bolts to rear with the two end ones set back to far corners of unertray.

Lastly I removed the bump stop rubbers at front just behind the front bumper.

The undertray hangs down now from rear, so slide it backwards and the undertray separates from the bumper. You might have to slide the undertray sideways to disengage from rear of bumper by front wheel arches.

Now the tray is off, make sure you take a note of the spacers attached to undertray as they are different heights. I was a bit unfortunate as 4-5 of mine became detached and fell off. We'll move onto them later.

Now slide under car towards heater box and locate 2No.black plastic flexi pipes, one is very obvious then other not so. At the ends of these pipes should be a rubber filter or non-return valve. Pull these out, making sure you hold the end of the plastic pipe with the other hand to avoid pulling the whole plastic pipe out of heater box.

That's job done! When you do this make sure your not in the path of the end of pipe as LOTS and LOTS of water comes pouring out.

All I had to do now is put the undertray back on. With the spacers that had become detached I had to glue them back on. This took 30-45min for glue to set as it was all I could find at short notice, so bear this in mind and my advise is to glue these on as soon as you remove your undertray. This way it gives you time to let it set whilst unblocking the drain tubes!

When putting all the bolts back, I copper slipped them. Also I gave everything behind the untertray a quick grease with my spray grease as a precaution. Whilst refitting the bolts, put them all back loose first before tightening them, to make sure everything lines up.

Lastly, I greased the bolt heads, I don't know why but it can't do any harm!

 

FOOTNOTE, Oakmere said that they remove all the pipework on their modification. I removed one complete pipe and upon inspection, I tired blowing down pipe and couldn't. I wondered why the pipe was SO blocked? Then when I removed the rubber non-return valve at other end, it was completely free! I preferred to retain the plastic flexi pipe as this is approx 10mm diameter and in my opinion, won't block from condensation build-up. Also with retaining the flexi pipe, I can still direct the water the same was as it was intended during design and not just drip from heater box to anywhere below.

 

TIP, I still couldn't get my low profile jack under the car to jack it up, so I rolled the car wheel that was on the roadside over a piece of thick wood first then the jack could slide under no problem!

 

I hope give someone some help and guidance to having a go themselves. And remember, a quick check by taking your fuse cover off and putting your air con on full and shining a torch down the heater tunnel will confirm if you have the same problem as I did.

 

 

BEFORE

 

 

AFTER

 

[superdavelotus]

Here's a shot of the rubber non-return valve (or whatever the correct term is called) from the end view. As you can see it tapers down to nothing and water has to pass through the slit.

[Simon350S]

There are 18 bolts to remove, sounds a lot but they come off in less than 10 minutes

Must be a pleasure after so many years grinding away at bolts and rusted captive nuts on the Esprit

Nicely done with the fix too!

[superdavelotus]

Yes Simon, you're spot on with the Esprit. That's why I am copper slipping everything as I go along, it what I did with the Esprit except it took longer to take off in the first place.

Even a car that's only 5 years old, I could still feel some bolts struggling to come out of the captive nuts around bumper. That's piss poor cost cutting in my opinion. How much would stainless steel bolts costs just for the undertrays compared to cost of car?

[TBD]

Good writeup. 

 

But, just to note, stainless steel bolts in combination with the aluminium chassis would be a no-go. Those two materials weld together and you end up having to drill the stainless steel bolt out. You won't find that combination used anywhere.

[superdavelotus]

Hi there, you find this application all the time in the construction industry when using aluminium, you have to use stainless steel fasteners. The standard is carbon coated steel screws and these would react with aluminium which is called electrolytic corrosion.

[TBD]

Hi there, you find this application all the time in the construction industry when using aluminium, you have to use stainless steel fasteners. The standard is carbon coated steel screws and these would react with aluminium which is called electrolytic corrosion.

I'm more into boating than construction. The electrolytiv corrosion between aluminium and stainless steel bolts (V4A) is a real nightmare. I've had the pleasure of a few stainless steel bolts in aluminium. There is almost no hope to remove the bolt a year later. I'd rather have the rusty bolts, at least if its underneath the car.

 

In any care, Lotus seems to be in good company here. I couldn't find any carmaker using stainless steel bolts in their aluminium chassis.

[Bibs]

^ What Thomas said. It's not penny pinching, the cost difference between mild and stainless in the car's bom cost would be negligible.

[Simon350S]

Anodised alloy bolts?

[superdavelotus]

Ok then what about all the bolts at front of undertray, they aren't screwed into the aluminium body but captive nuts and they are all corroded. These could be done in stainless steel. The remaining bolts could then be done as Simon suggested in anodised aluminium?

Mild steel in aluminium Is not a good combination.

[Bibs]

Why not ask Lotus? I'm sure they're aware of these products and have a reason they don't use them. We're talking a few pounds per car, it's not a significant cost increase.

[Simon350S]

How are the captive nuts fairing Dave?

If you are contemplating very long term ownership of the Evora, like you have with the Esprit, then it would be good to start the swap over of fixings bit by bit, spread the cost out a bit.

May be worthy of you starting a fixings swap thread, to save detracting from you air-con fix of this post.

[gregs24]

I do hope you didn't climb under the car with just a trolley jack supporting it !

[superdavelotus]

Greg,

 

I could add about the stand but I couldn't tell you where under the car I supported it. There's not much underneath there where you can put these things!

 

 

Simon,

 

The captive nuts were slightly grinding when undoing, so I helped the bolts outs a bit by inserting a wide flat bladed screwdriver between the bumper and the undertray. It felt like one may start to strip the thread so I didn't take any chances. I've now copper slipped them and greased the heads. I will go through the process of changing the fixings like you suggested, which is a sound idea IMO. I just need to have a think about other peoples input above and take on board. It may be that I may change the front ones for stainless steel bolts with captive nuts and the rears buy new Lotus ones and copper slip and possibly have the heads coated? In the meantime, I will read up on this stainless to aluminium problem. In fairness, my 26 years experience with working with aluminium and stainless is looked in a different light in construction. Once a product is fixed, it's designed to stay like this until end of life. The fixings aren't removed during this period, so I've never experienced that problem before.

I will start a new thread about this as it's a useful topic as other people must have the same thoughts?

[Bibs]

Duralac is very good to use in these circumstances, I use it all the time on my Elise.

[Simon350S]

That stuff has a very unfortunate name Bibs

Be very careful when you buy yourself a pack Dave!

[superdavelotus]

Hi Thomas,

 

 

I've just realised you said that you worked in marine environment? If so then you need to use a different grade of stainless fixing to prevent reaction with salt water and other marine harsh chemicals. In construction on a marine environment, we used different stainless steel screws than normal off the shelf ones. It's called austenitic but forget the actual grade.

 

 

Regards,

 

 

 

David Walters

[TBD]

Yes, its normally called V4A, at least here in Germany. Normal is V2A.

 

Unfortunately roads are salted almost everywhere in winter, the salt content is often higher than  seawater. 

[superdavelotus]

Hi Thomas, I think we call the grades A2 and A4 over here but pretty much similar to yours. I take on board your previous comments along with other forum members and will come to my own final conclusion on which route to take.

 

Hi Bibs, There's no point me asking Lotus as I didn't buy my car new and it's pretty much used now. I will just change a few items as I see fit. It was just my opinion and observation at the time.

 

I am just so relieved that I sorted my water ingress problem out and was able to do this on the roadside without the assistance of a ramp. Also it's good news that this corrective work can be carried out with basic tools and basic workshop skills.

 

 

Regards,

 

 

 

David

[JonneyB]

This is just what I am looking for but, forgive me if I'm being really stupid, I cannot seem to see this tunnel in the right hand upper side of front bay wall that you have mentioned.  Any possibility of a pic?  

I'm sure this must be what is wrong with mine so am keen to fix.  Ironic that I also have the gas strut problem also. 

[superdavelotus]

Hi Jonathan,

 

 

Please find below pictures as requested. The first picture show the fuse/ relay box. It you look to bottom right of purple relays, there is a gap behind the board.

 

 

Here's a close up of the tunnel I was trying to describe. I hope this helps.

 

[JonneyB]

Thanks for this,  hence why I couldn't see it as I have some inserts in there.  Anyway I removed the panel and had a look in the tunnel but couldn't see any water so thinking I'll just have to try the unblock method anyway.

Edited November 18, 2014 by JonneyB

[superdavelotus]

Hi Jonathan,

 

 

The tunnel is a long one (approx 400-500mm to the very back) and the water, if you have any, is right at the back. You need to angle a torch so you can see the end. I will try and get a photo a show you.

[superdavelotus]

Here's a picture albeit not a very good. My flash kept going off and only viewing the foreground. Anyway, if you look at rear, there's is a black thin slit, it's behind there, so it's pretty far back and hard to see at first.

[series_one]

Let me help.

 

It should look like this (fixed / correct).