header

Gallery

Marlin Owners Club





Welcome to our BMW E30 based Marlin Sportster Build Site,

we hope you will find this documentation interesting and helpful.

Marlin Sportster

The site has grown massively since its inception in 2005, I hope to one day soon improve the navigation as it's a bit overwhelming to start with. The main areas of interest to builders will be:

The rolling chassis build
Bodywork Fitting
SVA Issues
Final Assembly

If you would like read about the build in date order then have a look at his page.

It took 2.5 years to build the car and pass SVA and a lot longer to get to where it is now! To see the Sportster out on the road have a look at one of the videos here.

During 2008 we rebuilt the BMW engine from 2.5 to a 2.8 creating an M20B28 stroker engine. It uses the crankshaft from the later BMW M52B28 and the conrods from the M20B20. Not much more work is needed other than a clean up, slotting those bits together and a crank spacer. To read about the engine build click here (very picture heavy!)

Finally in March 2009 it was painted, a full set of images is here.

Can't see what your looking for? Try a:

 

To read the whole build from the start click here.

10/04/2008

Diagnosis Part 2

On inspecting the sump it turns out the ring terminal for the earth strap has broken, it was in place so that you could not see it had broken. There was a bit of contact but not much. This is the cause of the high oil pressure. Not much earth gauge OK when you put it on ignition 2, run the starter and it screws that up so the pressure goes up. Disconnect it and no earth = gauge on highest setting.

The also means the starter does not run properly as it doesn't get enough power.

Took the sump off. No obvious marks in any of the bores from the bottom. Push in the oil return and the oil runs out fine, oil pump seems to be OK.

Added a temp earth strap and now the starter runs fine turning the engine over without any problems (no plugs) - no odd sounds from it either.

Hypothesis is airlock (driving up hill), overheat and then unable to run anything due to the earth strap.  

Seizing probably due to small tolerances and overheat. Need to pull a cap off check a shell for damage.

Doesn't look as bad now as it did initially. I'm going to do have more of a look around, get a genuine water pump from BMW as the one I have makes a noise and a new sump gasket, new oil and filter and see how it goes.

09/04/2008

Diagnosis Part 1

Testing Round 1 (not much time):

I can hand crank it fairly easily now, it does seem to get a little notchy in places.

Also the starter can turn the engine over however I have to hand crank it a few time first.

I did noticed the oil pressure went really high after a few turns of the starter

Testing Round 2 (a bit more time):

Thermostat is fine, water pump seems to be pumping OK, but not pull it out yet (rad is in the way). Oil in the bottom was quite dark but not clumpy. Oil in the top was still quite light.

When you crank the engine on the starter a few seconds the oil pressure goes way way up - I stopped at 6 bar.

So me thinks there's a blockage somewhere. Not pulled the sump off yet, but that's the next step.

08/04/2008

Damn!

Was out for a drive today again as it was still sunny, unfortunately the engine over heated after 30 miles - only for a very short period of time maybe 30 second before I noticed. Let it cool but it seized up - balls.

Been towed home (not too far luckily) so this weekend will be take the engine to bits again time!

Took the plugs out and it is possible to turn it over so I'm hoping it's not too bad. Ran fine for 250 miles!

At least it still has 4 wheels this time

03/04/2008

Fuel Tank Breather

The breather that comes with the kit may not be ideal for injected engines, the tank pressurises during use to a very high level. As it is only a one way valve it only let air in as you use up fuel. The other issue we've been having is when there's a slosh of fuel it lets out a waft of petrol which really is not very pleasant.

Out solution was to get a mocal two way valve and a positive shut off so air can get in and out. Additional when there's a slosh it doesn't leak petrol all over the place.

Fitted the mocal valve today brimmed the tank and went for a long drive - no more petrol small wafting through the car when accelerating hard or going up a hill!

More info in the FAQ click here

30/03/2008

On the road again!

On the road again:

Sorry you'll need Flash installed to view this video!

March 2008 back on the road again!

March 2008

March 2008

March 2008

March 2008

March 2008

March 2008

March 2008

March 2008

March 2008

24/03/2008

Mudguard Stay

<p>New bits of steel for mud guard holders</p>

New bits of steel for mud guard holders

<p>Spacing for the carbon wings - ended up using 1/4 of one of these as space.</p>

Spacing for the carbon wings - ended up using 1/4 of one of these as space.

<p>Steel bent and fitted to the front of the carbon wing.</p>

Steel bent and fitted to the front of the carbon wing.

<p>Original wing mounts chopped and mounted onto the car. The standard holes needed drilling out slightly so that brackets would fit.</p>

Original wing mounts chopped and mounted onto the car. The standard holes needed drilling out slightly so that brackets would fit.

<p>Eyeing how much needs cutting off to fit the new steel.</p>

Eyeing how much needs cutting off to fit the new steel.

<p>After much fiddling, a bit of welding and grind and the wing is mounted</p>

After much fiddling, a bit of welding and grind and the wing is mounted

<p>Fits is not bad but the carbon wings are not quite as wide as the originals so it gets very close to the tyre.</p>

Fits is not bad but the carbon wings are not quite as wide as the originals so it gets very close to the tyre.

<p>Just needs paint now and the other side making.</p>

Just needs paint now and the other side making.

21/03/2008

Bracket + Nose Cone



Finally bit of construction. The original bracket that held the header tank was a bit floppy so Richard welded up a new one - nice and solid now!

<p>Plan A to hold the mesh in place on the nose cone - fibre glassed a set of nuts to on to it, then bolt it on. Final status - Epic Fail. The nuts pulled out.</p>

Plan A to hold the mesh in place on the nose cone - fibre glassed a set of nuts to on to it, then bolt it on. Final status - Epic Fail. The nuts pulled out.

<p>Plan B (Richard came up with this one) Tubes fibre glassed into the nose cone!</p>

Plan B (Richard came up with this one) Tubes fibre glassed into the nose cone!

<p>Fibreglassed in place</p>

Fibreglassed in place

<p>All tubes installed</p>

All tubes installed

<p>Some paint to clean up the work</p>

Some paint to clean up the work

<p>Complete</p>

Complete

<p>Mesh installed with ZIP ties</p>

Mesh installed with ZIP ties

<p>Close up of the final mounting</p>

Close up of the final mounting

02/03/2008

Windscreen part 1

To fit the windscreen you'll need some masking tape a pencil, rule and maybe a tape measure!

  • Put some tape down and mark a centre line on the scuttle - I used the bonnet hinge and my guide which was previous painstakingly placed in the middle!
  • Place the ali cover that goes under the screen on the scuttle measuring 130mm back from the scuttle edge (back edge inside car) on both sides. Also mark 60mm back.
  • Mark 7mm out from the metal edge - this creates a slot shop that the windscreen sides can drop into. Got to be careful that the holes are parallel with the edges of the screen!
  • Drill a series of holes inside the marked area, cut and file them out. Now you can drop the screen to test fit! That's about as far as we got this weekend!

<p>Windscreen loosly slotted through the scuttle</p>

Windscreen loosely slotted through the scuttle

<p>Stainless plates do a good job of covering holes chopped into the scuttle.</p>

Stainless plates do a good job of covering holes chopped into the scuttle.

<p>With the screen pulled back the metal of the screen frame pretty much touches the scuttle</p>

With the screen pulled back the metal of the screen frame pretty much touches the scuttle

<p>Screen should provide a decent amount of wind protection. Side screen may still need to be fitted!</p>

Screen should provide a decent amount of wind protection. Side screen may still need to be fitted!

<p>The driver side - the bottom hole just bolts in with a spacer, not sure yet how the top bolts in yet as the brackets have a huge bend in them that don't seem to line up with anthig.</p>

The driver side - the bottom hole just bolts in with a spacer, not sure yet how the top bolts in yet as the brackets have a huge bend in them that don't seem to line up with anything.

<p>The ali panel under the screen is not the right shape but once the rubber strip is added it almost fills the gaps - some filling work will be need to make it fit better.</p>

The ali panel under the screen is not the right shape but once the rubber strip is added it almost fills the gaps - some filling work will be need to make it fit better.

All we need now are some wishbones!

22/02/2008

Carbon Wings

<p>Carbon wings next to original</p>

Carbon wings next to original

<p>Carbon weave! Pretty!</p>

Carbon weave! Pretty!

<p>The new wing is not quite a wide as the original and follows a slightly tigher curve.</p>

The new wing is not quite a wide as the original and follows a slightly tigher curve.

<p>You can hardly see any difference between the two</p>

You can hardly see any difference between the two

<p>The wing over a 225 wide tyre, the thread is covered. Some of the bubble sticks out but that's an MOT pass.</p>

The wing over a 225 wide tyre, the thread is covered. Some of the bubble sticks out but that's an MOT pass.

<p>Side of a 225 / 45 / R17 tyre</p>

Side of a 225 / 45 / R17 tyre

<p>On the 205 width tyre - fits perfectly!</p>

On the 205 width tyre - fits perfectly!

<p>Side view on a 205/60/R15 tyre.</p>

Side view on a 205/60/R15 tyre.

09/02/2008

Engine in

Rear cover plated attached to block, sump bolted on and the flywheel on read to be bolted. The bolts need to be tightend up in a specific order and covered in loctite.

Clutch back on the fly wheel

Gear box slotted on "like a glove" [ace ventura]

After a lot of jiggling the engine is back in mated with the drive shaft and on all 4 mounts.

Just needs all the ancillaries bolted back on

Nice blue block, shame it has to be covered by the intake manifold!