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I have just acquired a previously built Marlin Roadster which I am planning to re-build/restore.
It has an interesting history in that the guy I purchased it from is the original builder. The car itself is correctly registered although never really finished having never been painted or trimmed. You could call it a blank canvas!
The kit is based on a Morris Marina (yes really!). This particular car used a 1.8 as the donor and so has a BMC B series engine. Not exactly a firecracker and pretty heavy but due to the love of the MGB there are plenty of tuning parts about.
It won't be a quick re-build so don't expect frequent updates!
Well it looks like you've mastered how to do pictures!
For info (as far as my knowledge goes) there are only small differences between the Marina 1.8 and MG 1.8 engines (dependant on age the Marina one may be more powerful than an older MGB one for instance). IIRC the crank on MGB was forged, but not on Marina. There may be some cam differences...... Just in case anyone tries it DON'T fit a 'fast' or 'high lift' cam to one of these as you'll kill the torque and (as they aren't meant to be a high revving engine) never exploit the extra power at high revs. Someone was bitterly disappointed years ago when his kit car (with 'stage 3' or whatever tuning parts he'd paid a fortune for with expert fitment) was noticeably powerless compared to my bog standard MGB engine(same kit car). The crankshaft pulley is a bit bigger than the MGB, but fits either crank (ask me how I know!) but of course needs a slightly longer belt.
Nothing wrong with those old "B" series engines. The 1800 TC ( Twin Carb ) Marina went really well and in the light Marlin will be quite quick. Simple upgrades such as an electronic ignition module to replace the points and the twin carb conversion if yours is a single will be all you need.
I was a huge fan of the Marina based Marlin back in the very early 80's - it was the kindest thing to do with BL's Finest (!!) saloon back then, far more subtle than dropping a caravan/grand piano/etc. on it like Jeremy C did regularly on Top Gear.
The old B series engine makes all the right noises and is simple and strong enough to be a very reliable lump with a bit of basic maintenance. Who cares if it's never going to worry a Fireblade rider in the insane 0-100-0mph dash between roundabouts on a sunny weekend?
As for the style to go for, it'd be option 1 above with Alfa badges for me all day long. A lot of people put Alfa/Fiat (and Toyota) twin cams in them back in the day, which justified the badges.
Hmm, I know I said there's nothing much wrong with a B series, but I wonder if the Twin-Spark motor from the cheap as chips 156 could be mated to an RX8 gearbox....
20200820_115115[1] by Robin Martin, on Flickr
Rear spring arrangement. Not the prettiest part of the car. I am considering shortening the spring by about 50mm and shortening the chassis accordingly thereby bringing the spring mounts closer to the rear tub. Sounds a bit drastic but I have seen it done on another car with no ill affects on the handling.
On the plus side I was ploughing through the history file that came with it and although it hasn't run for nearly 30 years it had an MOT just before it came off the road. So other than those items affected by time, mechanically it shouldn't be too bad. And I found an invoice for a new gearbox so that's one less thing to overhaul. The engine itself will need a complete rebuild I suspect. At least an unleaded head conversion. Currently thinking about the Peter Burgess EconoTune head which allegedly produces about 20% more power without much further modification.
Wow a dynamo! Remember if it is registered as a Marlin (some aren't) with the donor reg and pre-1980, it is probably tax-free. Have you joined the Marlin owners Club? Lots of help and advice there. B engined Roadsters do tend to overheat so if you have, keep the engine fan and put louvres in the engine side panels. No need to tune it, the B is no slouch. I have a B roadster. Good luck and remember it is supposed to be fun.P.S. I too love the look of the first pic. The Alfa look is great!
Finally made some progress albeit on the dismantling. Front wings, bonnets sides, radiator cowl and radiator all removed. No real horrors but the car was built before the availability of cheap stainless fastenings so I have had to dremel at least 50% of the screws.
A couple of surprises:
1. The engine still had water in it - but the original builder that I bought it from assures me it had been stored inside for the last 30 years so unlikley to have frozen up.
2. The offside torsion bar appears to have been making a bid for escape. It wouldn't have been much longer before that side of the suspension collapsed!
And some observations:
1. The bulkhead is beginning to crack arround the pedal box. Apparently a common problem.
2. The rad is quite compact but very chunky. I believe it originated from a Vauxhall Viva so I am suprised how deep it is. I have looked into alternatives but have come to the conclusion that getting it recored is the simpest solution.
3. The chassis itself has plenty of surface rust but nothing that a bit of cleaning up won't remove. I was a bit concerned when removing the rad is it had been fitted with just two primative brackets at the top and the bottom wedged between the chasis rails. but it seems no harm done.
I have also removed a few other odds and ends including the heater which wasn't salvageable. Anyone got a MK3 Spitfire heater going spare?
Apparently, if you replace the tie bar bushes with rose joints and remove the torsion bar coil-overs can be fitted on the front. They look nice too! BTW I am told by a reliable source that old plastic fans are liable to disintergrate.
Apparently, if you replace the tie bar bushes with rose joints and remove the torsion bar coil-overs can be fitted on the front. They look nice too! BTW I am told by a reliable source that old plastic fans are liable to disintergrate.
That's an interesting idea. I know some owners have replaced the tie rods but that alone isn't that useful. However replacing the torsion bars with coil overs means the suspension could be adjusted. Not possible with the torsion bars. I think a bit of investigation would be worth doing.
Cheers Robin
The problem with the torsion bar arrangement on the Marlin is the end of the torsion bar goes through a hole in the chassis. Meaning that the torsion bar angle and hence castor and camber angles are non adjustable. Changing to coilovers would eliminate that problem.
I found some info on the Marlin Owners Club forum about the coilover solution. The only issue I can see is that the original bracket for the damper mounting wasn't designed to take the weight of the car so may need beefing up or remaking.
Cheers Robin
Yes, but that's only important if there's a benefit of having the adjustment. I've known people fit vernier pulleys to camshafts, but leave them in the standard orientation - or worse still just change the setting without any knowledge of whether it's made the situation better or worse (for their desired outcome)
I have been experimenting with rust removal using electrolysis. There is a lot of info about it on t'internet but I am always suspicious of magic solutions to rust removal so I thought I would try it. Amazingly it works!
I used a large food container with some re-bar as the anodes and a weak solution of Sodium Carbonate. I already hace a handy 12 volt supply in my "man shed" so that bit was easy. I adjusted the current flow to about 1 amp with a couple of resistors. Not sure if that is right or not but seems to work. I guess it depends on the size of the piece you are de-rusting.
It seems to be a great process. Removes the rust without removing any underlying metal. And far lesss messy than a wire brush in an electric drill. If you try this though, the process generates hydrogen, so it must be done in an area with good ventilation or preferably outdoors.
Now all I have to do is the 100's of other parts...
I rigged up a similar tank when I restored my 49 Triumph Roadster. I could do a couple of parts at a time but it was an over night process. In the end I resorted to the blast cabinet with aluminium oxide grit. So much quicker and thorough in my opinion. What took 12 hours in the tank could be done in two minutes by blasting.
In the end I resorted to the blast cabinet with aluminium oxide grit. So much quicker and thorough in my opinion. What took 12 hours in the tank could be done in two minutes by blasting.
I don't have that luxury unfortunately. Electrolysis might be slow but certainly cleaner that the old wire brush in a drill. And I am not in any hurry.....
The fuel tank mounting is - err - interesting. Just dangling from some metal straps. For some reason the builder had ignored the flanges on the chassis that it was supposed to be fixed to. It must have been reasonably secure as the car had done 30k miles like this. Does anyone recognise the tank? Rumour has it it was from a MK1 Escort estate. Now unobtanium of course so I will have to look for something else.
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.
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).
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