The MARLIN of Dorian Gray......

[Waterscumbietoo]

It is I, [email protected]

Have a prodigal Marina 1.8cc based Marlin Roadster MKII (brought as a kit from Paul Moorhouse, way back in March 1983).

Lost track of it in March 2007 and police recovered it in Feb 2014. Rolling chassis and most body panels sound, but everything else ruined or missing

So going for a complete re-build. Photo is as the police recovered it.

Biggest concern is finding a bonnet (will also post in 'Wanted'). All ideas welcome

avid.

2015-02-23 11.36.48.jpg

[b_caswell]

Re: The MARLIN of Dorian Gray......

I can put you in touch with a member who did have a right hand half of a second-hand hinged bonnet. Trouble is they get tweaked to suit each car
You could have ago at making your own.

[Waterscumbietoo]

Re: The MARLIN of Dorian Gray......

I can put you in touch with a member who did have a right hand half of a second-hand hinged bonnet. Trouble is they get tweaked to suit each car
You could have ago at making your own.

Thanks Ben, please do so. Might use it as a pattern to make other side and either have a hinged one, or get an entire single piece version made. Early days.

avid

[b_caswell]

Re: The MARLIN of Dorian Gray......

Hi David, Have sent you a PM with the contact for the half a bonnet.

[Waterscumbietoo]

Re: The MARLIN of Dorian Gray......

Hi fellow Marlinetts ,

And thanks to all who have sourced items for me, or offered advice, so far. [Need ideas for a front grill, the standard "kit" never made it back.]

Anyway it's been a while, life, job hunting (still on going), property matters, restoring to minty fresh a second MX5 (1998 NB 1.6 with bolted on hardtop) and motorbike fettling have all pushed my re-imagining of my Marlin lower down my Bucket List, but I have had made some progress.

> Rear diff and all brakes and suspension refurbished and repainted. Have a kit to make up new clutch and brake lines, once the drive tunell is modified and refitted.

New engine IN.jpeg

> MX5 1.6 DOHC engine refurbished and positioned in chassis to confirm driveshaft length and intended engine location to clear bonnet and to see how much room I have to play with (not a lot).

Driveshaft positition.jpeg

> Gaffa tape just to hold the shafts together till I measure up and tack weld for the shaft to be properly welded and balanced. Also need to come up with a gearbox support bracket which will be mounted in the new drive tunnel as per the original for the Marina 1.8 gearbox.

Next priority is to make up a new steering shaft. Needs to have a dog leg with some Land Rover universal joints and a pillow-block support bearing to route the steering shaft round the MX5 engine to connect to the steering rack existing position. Saw the earlier warnings about changing the steering geometry, so decided to leave well enough alone

As always, all comments or advice much appreciated.

avid.

[HairyDave]

Re: The MARLIN of Dorian Gray......

Looking good, it doesn't seem to have suffered much cosmetically. Funny how the mundane things in life keep getting in the way of real life! Why not make a dummy bonnet out of thin caravan ally (easy to work) then use it as a pattern? Good luck!

[jon_cox]

Re: The MARLIN of Dorian Gray......

Hi David,
I am sure it is just the angle of the picture or perhaps the engine is not in its final position, but it looks like you have quite an angle acting on the prop uj's.
Have you had to offset the engine to the drivers side to fit the intake plenum in without bodywork modification? If so have you kept the drive train centre line parallel to the the car centre line?
If not then how are you dealing with the propshaft UJ angles? I have been looking into the fitment of the MX5 MK2.5 vvt 1.8 engine (Slightly longer than 1.6) but the offset required for the intake plenum, whilst keeping the drive centre line parallel to vehicle centreline is a real head scratcher.
I have been looking into the possibility of using CV joints instead of UJ's. This was done in the past on later dolomite sprints and TR7, TR8, Triumph Stags when they realised that the vibrations were being caused by poor drivetrain to diff alignment as the engineers had not factored in the effect of unequal UJ angles.

Watch this video to understand what I mean.

https://www.youtube.com/watch?v=Idk3BVDVHq4

TR7 5 speed prop with CV joints at each end
propshaft.jpg

[Waterscumbietoo]

Re: The MARLIN of Dorian Gray......

Hi David,
I am sure it is just the angle of the picture or perhaps the engine is not in its final position, but it looks like you have quite an angle acting on the prop uj's.
Have you had to offset the engine to the drivers side to fit the intake plenum in without bodywork modification? If so have you kept the drive train centre line parallel to the the car centre line?
If not then how are you dealing with the propshaft UJ angles? I have been looking into the fitment of the MX5 MK2.5 vvt 1.8 engine (Slightly longer than 1.6) but the offset required for the intake plenum, whilst keeping the drive centre line parallel to vehicle centreline is a real head scratcher.
I have been looking into the possibility of using CV joints instead of UJ's. This was done in the past on later dolomite sprints and TR7, TR8, Triumph Stags when they realised that the vibrations were being caused by poor drivetrain to diff alignment as the engineers had not factored in the effect of unequal UJ angles.

Watch this video to understand what I mean.

https://www.youtube.com/watch?v=Idk3BVDVHq4

TR7 5 speed prop with CV joints at each end
[ATTACH]11497[/ATTACH]

Thanks Jon,

I had seen the UT clip before. Was just positioning it for the length the prop shaft, think it is about right for where I want the gearshift to be, and with enough clearance between the back of the engine/bell housing and the bulkhead. I am also considering anglinging the engine slightly to the left, along its horizontal axis to give better clearance for the intake plenum and allow better clearance for the steering column. WIll position the right side engine bay housing before I do any final permanent fixing of the engine to engine brackets and welding in new engine mounts.
]
I intend for the driveshaft to be perfectly horizontal when the dif/chassis/suspension is "at rest" on my garage floor. And looking from above the shaft will be at a a right angle to the rear axle.
]
Fun part is the final position/angle of the gearbox/engine and making up the engine supports. Still have to find the right engine mounts and place to fix them to the chassis.
]
Also in two minds about re-using the original Marina pedal box and pedals, or see if the MX5 pedal box and brake servo (much slimmer that the Marina one) could be used instead.

How far have you progressed with your build?

Regards,

avid

[jon_cox]

Re: The MARLIN of Dorian Gray......

Hi David
No physical progress so far. Have been at the planning stage for a few years........
Too many distractions in life at the moment. I did not even put the car on the road this year due to other projects.
Hopefully get things going after the summer.
What are your plans for fuelling? Will you change the fuel tank for a custom made job with sump, baffles and fuel line return? Or go the swirl pot route?
If you change the pedal box to mx5 will you need to change the steering column position or perhaps use the mx5 column?
Trouble is every decision has a knock on effect which sends you round in circles.

Jon

[Waterscumbietoo]

Re: The MARLIN of Dorian Gray......

Hi David
No physical progress so far. Have been at the planning stage for a few years........
Too many distractions in life at the moment. I did not even put the car on the road this year due to other projects.
Hopefully get things going after the summer.
What are your plans for fuelling? Will you change the fuel tank for a custom made job with sump, baffles and fuel line return? Or go the swirl pot route?
If you change the pedal box to mx5 will you need to change the steering column position or perhaps use the mx5 column?
Trouble is every decision has a knock on effect which sends you round in circles.

Jon

Hi Jon,

Current intention was a custom fuel tank to replicate the MX5 one, with existing MX5 components. Have already refurbished the current fuel pump and combined sender unit. Was also thinking of having the battery in the rear rather than in the engine bay (I already have the wiring harness from the MX5).

Was not aware of the "swirl pot" solution, any good links? Will have to do some homework. I need a new fuel tank whichever way I go.

Going to have to modify/re-install the drive tunell and make up a gearbox support bracket, similar to the Marinia version, then make the final adjustments for the alignment of the drive shaft and engine support mounts. Then I can look at pedal box solution.

Truth be told, I enjoy solving each technical challenge just as much as driving the Marlin. And I suspect once I finally get the Marlin back on the road the way I want it, I will be looking round for something else to fettle, now that I have all the tools necessary. But as they say, no such thing as "all" to an addicted DIY mechanic

[Waterscumbietoo]

Re: The MARLIN of Dorian Gray......

UPDATE: Steering column re route now sorted ("L" shaped rather than straight through). Two extra UJs, a support bearing on a "pillow mount" bolted to the driver side engine bay panel, extra 450mm long (14mm diameter) steel rod and cut down the originally supplied steering shaft to retain the T coupling at the top. Did not need to relocate the steering rack.

Next challenges are:


> Mount either the Marina pedal box and brake servo or the MX5 pedal box and servo unit, depending on which will not foul the new position of the steering shaft. Or go for another purpose-built floor-mounted box from a specialist maker (have seen a few)



> Get the gearbox end of the MX5 output drive shaft mated to the shortened Marina driveshaft and have it balanced.



> Finalise the position of the engine once the drive shaft is re-fitted and sort out the location and type of engine mounts I need.

> Then out comes the engine & gearbox to weld in the new engine mounts (once I've worked out the correct mix), fit new clutch basket, clutch plate and throw out bearing, then put the lot back in the engine bay and bolt the engine down and make up a gearbox support bracket similar to the original one that came with the kit.

Love it when I can lay out all my fantasies like this, ignoring all the little "gotchas" I'm going to have to overcome.

Bye fer now......

[jon_wilkinson]

Re: The MARLIN of Dorian Gray......

Pikchers or it didn't happen

[Waterscumbietoo]

Re: The MARLIN of Dorian Gray......

Pikchers or it didn't happen

OK, you asked for em....

Adapted original T piece from Marlin supplied steering shaft to 1st additional UJ, and short extension to 2nd additional UJ to support bearing

Adapted original T piece.jpeg

2nd UJ to the support bearing on "Pillow Mount" fixed to driver side engine bay panel to take 450mm steel rod

Support bearing on pillow mount.jpeg


450mm steel rod connected to original UJ and steering rack

Straight run to OEM steering rack.jpeg

[jon_wilkinson]

Re: The MARLIN of Dorian Gray......

Thanks. Always good for others following in your footsteps in the future.

[Waterscumbietoo]

Re: The MARLIN of Dorian Gray......

Pardon my ignorance, but what is the difference between/benefits of UJs over Constant Velocity joints?