S4s rolling restoration project

[tomcattom]

Not touched any of the suspension yet. Hoping I can work out what I have for front castor and rear toe by inspection 🤞. Front camber is going to require some disassembly to work out what is currently in there from what I understand from reading the workshop manual. That bit will wait until next month now when I take the tanks out ready ready for the shiny replacements.

If it has to wait until it's apart then it'll just wait until I start on the suspension overhaul in the Autumn. At least I have a feeling for what's going on.

[Chillidoggy]

Depending on how much rust/corrosion there is, its worth removing the top wishbone arms to see whether you have the correct amount of shim washers what size they are, and where they’re located. If you can get a median on the shim washers, then the remaining adjustment can be done at the ball joint end. Mine had everything and the kitchen sink on one side of the ball joints but still the castor was out, so moving the shim washers proved to be a good job.

Then you can check the shim plates and castor plates at the same time. An easy job for once!

Rear shims are more tricky, but unless you just buy a load of them and hope for the best, then there’s no way around it.

[tomcattom]

Been enjoying the car over the past couple of months since passing the MOT with the only minor issue of note in that time being the case of Tourettes that my speedo developed. That was cured with a combination of a new wheel speed sensor and cleaning all the accumulated crud out of the teeth in the toothed ring on the drive shaft.

 

The car is now SORNed once more because my new fuel tanks are scheduled to be crafted by Axminster Specialist Panels in the coming weeks and I need photos of the current tanks so they can make sure they build the right thing for me. So today was the day I removed the old tanks.

My creative use of the garage door frame to hold the deck lid up while the gas struts were disconnected to allow removal of the tanks. I initally thought I'd need to remove the deck lid completely, thankfully not!

 

It took all day, but with the help of a friend we got both tanks out inside the day. Engine required some disassembly to make clerance to get the tanks out.

Quite a lot of rust debris found on this side.

 

Having inspected the tanks it's clear both have been out for repairs in the past, but sadly the repairs aren't very good, the passenger side tank being the worst and the one that was disconnected when I bought the car. Here are some photos of the repairs found on that tank.

Couple of patches welded in the base. The whole thing looks to have been coated in a thick epoxy type coating, but it seems whoever did it didn't think it was worth trying to clean the surface corrosion off first so the coating is just flaking off in big chunks all over the place 🙄

And there's the source of my fuel leak!

 

Just got to await the arrival of my new tanks and everything can go back together again

[Barrykearley]

Straight in the skip with them things 👍

[Chillidoggy]

Good work, Tom. When those tanks arrive, they're so nice you won't want to put them in the car.

Might be worth fitting a new tailgate release cable while its out. If they break, you're in a world of pain.

[jonwat]

Very shoddy work on those tanks especially after all the effort to get them out 

[tomcattom]

6 hours ago, Chillidoggy said:

Good work, Tom. When those tanks arrive, they're so nice you won't want to put them in the car.

I'm hoping to collect them myself since Andy lives very near my family. It's a fascinating place to look around having been over there once before.

6 hours ago, Chillidoggy said:

Might be worth fitting a new tailgate release cable while its out. If they break, you're in a world of pain.

Wasn't aware they were problematic. Hopefully they're not too expensive or difficult for me to obtain.

6 hours ago, jonwat said:

Very shoddy work on those tanks especially after all the effort to get them out 

My sentiments exactly. Especially after the battle my friend and I fought with that tank in particular to get it out yesterday!

[Chillidoggy]

Ref the tailgate cable, I don’t think they’re silly money, and failure is not unheard of, which is why I changed mine.

If the cable fails, the only way I know of to open the tailgate is to cut an arm-sized hole behind the number plate, then try and reach the catches. This is of course assuming other arrangements haven’t been made, such as stringing bits of wire from each catch going to a hole somewhere accessible.

[tomcattom]

Is it worth me replacing/upgrading the fuel pump while the tank is out? Don't know if they're prone to issues, but assuming its the original in there that makes it 25+ years old and with the tanks out its as easy as it ever will be to replace it.

[Sparky]

I will just say that I detest doing the pump insitu.

[cweeden]

At the least you will want to look at the in tank hoses. If they are original I'll bet they have many cracks. Be sure to use hose suitable for submerging in fuel as well as carrying it. 👍

[tomcattom]

Things are a bit quiet at the moment partly because I've been waiting for my new tanks to be made and partly down to the arrival of our first child, a little baby girl which I'm over the moon about.

The fuel tanks are now complete and passed their pressure test and are waiting for me to collect. I'm planning a trip down to Devon at the start of November so I'll be collecting them myself direct from Axminster and hoppefully I'll be able to get them fitted fairly soon after.

Anyway, before our little girl arrived I did manage to get the fuel sender and pump out of their respective tanks. There was quite a bit of rusty detritus around the fuel pump pickup area in the RH tank, but otherwise it doesn't actually look too bad in there. I had no particular concerns about this tank, so I think think this tank might still have some life in it given a quick clean out.

 

The other tank is definitely destined for the scrap heap. Its got a nice film of surface corrosion all over the inside, probably due to the fact it's been left empty and likely sweating over the past three years or more. But here is another perspective of the most significant "repair" on the LH tank.

 

Going to be ordering a new fuel pump and I've also noticed that the low fuel warning light doesn't seem to come on consistently. Having inspected the fuel level sender it looks like it's just a case of a light film of surface corrosion on the low fuel contact is the cause of that, probably due to the fact it's been in an empty fuel tank for quite some time. Will clean it up and give it a test and make sure its all functioning correctly before it goes back in.

The new power steering pipes from Lotus Bits have also arrived and first impressions of them are that they look good. Hopefully they will fit nicely too.

[tomcattom]

Tanks have been collected and are securely lashed down for the 160mile journey home.

The weight saving on them feels pretty significant. I will compare weights more scientifically out of idle curiosity when I get home. Looking forward to getting them fitted now 😀

[Chillidoggy]

If they’re the Axminster tanks, you’ll want them on display in the living room.
 

Trust me on this.

[tomcattom]

Yup, they're Axminster's finest export.

Pure welding porn from what I briefly saw of them before they were bubble wrapped to load into the van.

[tomcattom]

Unwrapped the tanks this morning to take a better look at them and I'm really, really impressed with them.

RH tank

 

LH tank

 

You were right about the quality of them @Chillidoggy, the fabrication and welding in particular is exquisite. There is a small part of me that wants to put a window in the side of the car to show them off 😆

 

Given the tanks felt significantly lighter than the OE items I decided to do a quick crude weigh in with my bathroom scales to see what the difference really was.

OE RH Tank - 10.5kg

OE LH tank - 10.0kg

 

The new tanks on their own were too light to get a reading from my scales, so I had to weigh them together.

The two together weigh 9kg, less than the lightest of the original tanks on its own. I think Mr Chapman would approve The actual weight comparison is shown below for those that are interested.

	OE steel tank	Axminster alloy tank
RH Tank	10.5kg	4.7kg
LH Tank	10.0kg	4.3kg

 

[LotuStuart]

Nice. And the quality looks superb. Shame to hide them away.

[tomcattom]

Been stealing the odd hour here and there over the past week to get the tanks assembled and ready to go into the car.

First task was to get the low fuel warning light sorted. As I suspected the light surface corrosion on the float arm was causing an unreliable contact. A light rub with some 400 grit wet and dry on the arm at the point hlighted below and the stop at the bottom of the sensor has resulted in a reliable contact again. I've no idea if the fuel sensor/guage actually works, but I've meansured the fuel level sensor and it has a full swing resistance 315ohms when empty and 0ohm when full.

 

Next task was to replace the fuel pump as a precautionary measure. Having done some reading on the forums the Sytec pump seems to be a known upgrade so I thought I'd give it a go. I wasn't able to find an ITP016 pump as used by others on here, but after some research I found the Sytec SYT340G pump seemed to be the best candidate and after consulting with Fuel Pumps Online they sent me the SPK0244 kit with all the necessary fittings. The eagle eyed may spot a notable difference in the pumps...

 

The pump, pulsator and loom removed from the pump "cradle" alongside the new components to go in.

 

I immediately ran into a minor issue in that the OE pump pickup is not concentric with the body, where the Sytec replacement is. A new rubber boot/foot is supplied with the pump kit, but because the OE pump isn't concentric the frame it sits in at the bottom of the cradle is also off centre. The rubber boot supplied required a little "fettling" to make it fit because the OE boot couldn't be used and I couldn't find any alternatives online that would fit out of the box.

Boot before

Boot after modification. I took a bit too much rubber off in one area resulting in a hole, but it won't cause any issue and can't be seen once fitted.

 

The length of loom supplied with the pump doesn't have the connector to mount onto the bulk head connector, its just comes with two flying leads. I didn't want to cut up the original loom for the bulkhead connector in case I need to go back to an OE pump. I had real trouble finding out what the connector is, but I did eventually find a place in the US selling the correct part. Here are the two looms side by side.

 

Pump fully reassembled in its cradle ready to go in the tank.

 

I've also cut new set of foam pads for the top and bottom of each tank from a sheet of 20mm thick self adhesive closed cell foam, using the old pads as a template.

 

All fitted to the underside of the tanks

 

Fuel level sensor and pump both refitted and after a little trimming, the pads fitted too.

 

The tanks are now all ready to go back into the car. Hopefully I'll get a chance to do that next weekend.

I've also repainted the engine mounting legs and inlet plenum support brace using some VHT paint. The left size leg I've actually sourced a replacement for; the old one was suffering at the mercy of long term corrosion. I'm sure it would be fine to continue using, but given a replacement was fairly cheap I bought a new one.

All prepped a ready to paint.

Three coats of VHT primer and three coats of black VHT engine enamel later. They're currently in the oven baking - don't tell the missus 🤐

[drdoom]

What is the purpose of foam on tank undersides?

[Barrykearley]

Stops them rattling and banging - and eventually wearing through the fibreglass

[tomcattom]

After hoovering up all the accumulated rubbish in the tank wells, drilling out the crossover pipe grommet rivets (no easier than the first time I did it!) and replacing a couple of the sidewall securing rivets the tanks are now in. Seemed to go in much easier than they came out. Probably helped that gravity was on my side this time and also the tanks each weigh half as much as before.

 

If I get chance tomorrow I'll be aiming to get the engine secured back onto its mounts.

[Giniw]

Did you put them directly on the GRP? I think they should be on a foam (which keeps the humidity but I guess it could be replaced with one that doesn't ^^)

[tomcattom]

On 14/11/2021 at 18:41, tomcattom said:

All fitted to the underside of the tanks

[Giniw]

woops sorry I missed a few steps indeed!

This is very neat!

[tomcattom]

Sunday turned out to be a bit of a bad day in the garage. To start with I tripped exiting the conservatory while carrying the freshly painted engine mounting legs to the garage, throwing them across the driveway, chipping the new paint off them and in the process trashing one of the conservatory door blinds 😧 So after repainting them for a second time I decided to put the boards on top of the tanks to run into my next problem; they wouldn't fit....

Oh look, the tanks are back out of the car again Turns out I made a bit of a cock-up with the foam pads on top and bottom of the tanks. I measured the original sponges and they were 20mm thick, so I order the same thickness in the replacement closed cell foam. What I completely failed to consider in doing so, was how much the foam gets compressed during installation of the boards on top of the tanks. With the 20mm neoprene foam I used initially it barely compresses at all, which meant the tanks sat ~20mm too high in their wells and so I couldn't install the top board brackets back onto the bulkhead because the tanks were in the way.

Throwing the engine mount legs across the driveway probably saved me some time in the long run, because had I refitted them on Sunday as planned I'd have had to take them straight back off again to get the tanks out for a second time. Silver linings and all that!

After sourcing some 10mm thickness foam, removing the first batch from the tanks and refitting them I'm now back to where I was last Saturday, with the top board fitted on the passenger side to prove it does now fit 😌.

 

Next challenge is to work out how to get the tailgate release cable off the cabin release lever so I can replace that before I refit the tank board on the driver's side. It'll be much easier to replace with the board out of the way I suspect, particularly since the ECM won't be in the way.