Marlin Roadster (Re)Build

[peterux]

Looks like it was held on by the filler pipe!!

These chaps do quite a few alternatives...
https://www.compbrake.com/product-ca...ks/fuel-tanks/
but I'm sure there are others
Cheers, Peter

[AlanHogg]

Escort estate mk1/2 tank is what was used but not obtainable new anymore. Midget/Sprite is one i believe will fit or maybe better to go custom alloy/stainless.

[Mitchelkitman]

Maybe hung on straps to gain a bit more boot space?
If it's an escort estate tank, I bought a brand new one for my Rickman. (probably 3 years ago - time flies).

[jonkoxe]

Hi Robin
What you have there is not an Escort van fuel tank. Looks quite different, which could explain the unorthodox fitting method. Keep an eye on eBay as the escort tanks do come up now and again. Looking forward to more rebuild pics.
Jon

[Mitchelkitman]

An MG B or Midget tank will (I think) have a flat top, and will be easily available new.

[MartinClan]

Removed the engine this weekend. I decided to drop it out underneath as that avoided having to use my hoist. Nothing wrong with using a hoist to remove the engine but it's not a job I like to do single handed. The old B series is a heavy old thing.
Getting the chassis up high enough was a bit tricky. The slightly dodgy looking supports (axle stands on wheels) were actually very stable.
engine_out4 by Robin Martin, on Flickr

And the engine in all its oily glory. I had forgotton how old school british engines tended to leak. The gearbox is actually almost new in that it was replaced just before the car was taken off the road 30 years ago. Hence the green paint.
engine_out1 by Robin Martin, on Flickr

Next job is to clean it all up before it is allowed to go into my fairly clean garage. Not looking forward to that....

Cheers, Robin

[peterux]

Good progress, Robin!
That gearbox looks like it came off a tractor :-)

[MartinClan]

Originally Posted by peterux

That gearbox looks like it came off a tractor :-)

Must be the colour lol.

[MartinClan]

It's been too cold do do an awful lot on the mechanical side as the car is outside atm. But I have done a little work on the first of the fibreglass mouldings, all of which need some form of repair.
Here's a before
scuttletop1 by Robin Martin, on Flickr

And after
repair1 by Robin Martin, on Flickr

My main question now is what primer to use? There doesn't seem to be one answer unfortunately. I have "discovered" Epifanes Multi Marine primer which allegedly is good for fibreglass, steel and aluminium of which I have all. As I will be coach (hand) painting the car it may fit the bill.

Cheers, Robin

[Mitchelkitman]

I'm also an advocate of brush painting. IMHO the most important aspect of making the primer 'stick' to GRP is the surface finish - 320 grit is my preferred preparation. Paint suppliers (who often know nothing about GRP anyway) state all sorts such as "you need plasticiser in the paint - that will be another £10 a litre please". Many years ago someone who'd painted his car said to me "just use red oxide primer". I was planning on painting the GRP 'bumpers' on my Dutton at the time. The Red oxide (follower by satin black) just using aerosols came out great, and gave no future issues. Ambient temp is also very important, much too cold at the moment!

[Lucky@LeMans]

I've used Davids 182 primer on GRP and had no issues. For ali you really need an etch primer, they are cheap enough and readily available in aerosol form.

[MartinClan]

The front suspension is now entirely off revealing some fairly horrible construction in places. Odd bolts, holes in the wrong place etc.
without_front by Robin Martin, on Flickr
And aso plenty of evidence of the use of a large hammer when the suspension was removed from the donor, plus the torsion bars are well and truly rusted into the suspension arms at one end and the adjuster at the other. Amazing it ever passed an MOT but then things were rather different 30 years ago! Good job I bought a spare set of front suspension components off Ebay - between the two lots should be able to make one decent set. And the chassis itself hasn't been butchered at all.

Just the rear to dismantle now. The rear axle case is very rusty, particularly arround the spring saddles one of which has a hole rusted right through it. It looks like some serious repairs may be needed. I am also currently trying to get some prices for new rear springs. The plan is to:
A. Have then slightly shorter at the rear to avoid the spring sticking out look that the Marlin suffers from.
B. Have them made flatter than standard to avoid using the 'orrible lowering blocks that the car currently has.
rusty_axle by Robin Martin, on Flickr

And I learnt something today. I was suprised to find that the springs are assymetric in that the axle is positioned further forward than centre of the spring by some 4 inches. Curious as to why that was I did some Googling and it seems it's to reduce axle wind up (tramping) under heavy acceleration. And I always thought leaf springs were simple!

Cheers, Robin

[MartinClan]

The chassis is pretty now pretty much dismantled and ready to be moved up to the man shed for restoration and a couple of planned modifications. I'm surprised how heavy it is - I guess the box sections must be quite a heavy gauge.
bare_chassis by Robin Martin, on Flickr

The rear axle, although being generally good, has rusted through spring plates and so I will have to do something about those. I think the only solution is to cut them off and fabricate some new ones and have them welded on. The position is fairly critical though. Apparently the diff flange needs to be 3 degrees off vertical otherwise the UJ's in the propshaft suffer.
spring_plate1 by Robin Martin, on Flickr

The rest of the spring mounting hardware seems to be OK other than the U-Bolts which I had to take the Dremel to. Even the rubber pads look servicable, although you can get new ones from SuperPro at a price that's not nice.
The large lump of rusty steel is a lowering block. It's 'orrible and doesn't feature in my rebuild plans!
spring_mounting by Robin Martin, on Flickr

[MartinClan]

In my drive for a slightly more modern and safe car, and after some searching, I managed to find a rare Marina pedal box with servo and dual master cylinder (wow). Both were options would you believe...

pedal_box by Robin Martin, on Flickr

The servo looks pretty grotty and new ones are non existant. It's possible to get them rebuilt but apparently with this type (crimped construction) they have to saw them in half and then weld the two halves back together! I suspect that may be outside of my budget. But a bit of Googling has revealed that the Landrover Seies 3 servo has the same mounting points and looks very similar, and importantly is freely available. So I may take a punt and buy a new one of those. Can always sell it again on Ebay if it doesn't work out.

I am hoping to be able to rebuild the master cylinder. next job is to strip it to see what the bores are like. Can anyone idenity the model number? It's (obviously) Girling but do the long string of numbers mean anything? Unfortunately the Marina, even with the rare servo and dual master combo, used 4 different models so I can't identify it that way.

master_cylinder by Robin Martin, on Flickr

Cheers, Robin

[AlanHogg]

I worked in the distant past for AP products {Lockheed, Borg and Beck] so not overly familiar with Girling . From what I remember the master cylinder number is only relevant for the first 8 digits ie 64678912. The Lockheed servo you could dismantle in that the two halfs locked together with a quarter turn, easy with the correct tools but possible with some ingenuity. I'm sure someone on the Owners club forum when looking for an alternative [similair problem] found a more modern set up that required little work to fit. Maybe off a Renault. Will see if I can find the details.

[AlanHogg]

Seems Peugot 205 with an adaptor works well according to Marlin owners club post

[Mitchelkitman]

When I wanted a servo to replace one on my Rickman Ranger (Escort mk2), a Land Rover one was ideal. £60 brand new (Britpart) compared with the £300 a specialist wanted to try (not definite) to fix the escort one. just needed a small mod to the pushrod and in under 3 hrs (taken at leisure) I'd removed and replaced. If it ever needs replacing I'm confident it will be available in the future.
ETA, the master cylinder (from Land Rover) looks like it would also have been suitable (with a union change on one brake pipe), but I was able to use the Escort one, as it fitted perfectly.

[MartinClan]

Good and bad today.
First the bad news....
I attempted to dissasemble the master cylinder and it's just one mass of rust. I don't think it's worth saving.
master_cylinder_us by Robin Martin, on Flickr
So the hunt is on for an alternative. After a lot of Googling I found the GMC234 which is used on the TR6. It is designed to be mounted at an angle, and the bore is 20.3. A bit larger than the cylinder used on the Marina but probably not disastrously so.
gmc234 by Robin Martin, on Flickr
It also has the advantage that the servo it is used with (still available new) looks pretty much identical to that used on the Marina.

And the good news is, after much fretting, I decided to go for drilling out the old studs on the exhaust manifold and re-tapping it to fit new ones. All my other efforts at removing the old ones had failed miserably. But in the end it proved to be much easier than I thought.
manifold by Robin Martin, on Flickr
The observant might notice one of them is a bit on the p!ss. Well 5 out of 6 isn't bad and I don't suppose anyone will notice!

And this arrived in the post. The Alfa 8C was what the Marlin was loosely based on. You can see the family resemblance.
alfa_model by Robin Martin, on Flickr

Cheers, Robin

[MartinClan]

The TR6 servo and master cylinder arrived today. Pretty much a perfect fit other than the servo needed packing out about 6mm. Temporarily done with washers but I willl make a proper spacer. The angle of the reservoir on the master cylinder is identical to that of the standard Marina one so fluid levels should be good. I do like it when a plan comes together.

new_pedal_box by Robin Martin, on Flickr

I should mention that the Marina pedals are shortened for use in the Marlin and someone has drilled go-faster holes in them...

Cheers, Robin

[peterux]

Looks like an excellent solution. It may be the camera angle but it looks like an unusually shallow reservoir, presumably to clear the tr6 bonnet?