DRL152K Marina based roadster rebuild

[martinclan56]

However the Accuspark electronic kit to fit inside your rebuilt dizzy is well worth installing to replace the points and condenser.

If you type in this deliberately misspelled word " Lucal 25D" on AliExpress. They do the kit for approximately 1/2 the price of Accuspark & mine arrived in Accuspark packaging for £22.

Yes I was thinking about doing that. Appart from anything else the quality of the points available nowadays leaves much to be desired....

[Ye Ol Ripper]

I have found that the Chinese distributors from Accuspark, Powerspark & the MG club are actually incorrect for the B series engines , having the incorrect advance curve as you have now discovered. All originate from China.

Don't forget they also fit the A series engines.

They also had various advance curves.


However the Accuspark electronic kit to fit inside your rebuilt dizzy is well worth installing to replace the points and condenser.

If you type in this deliberately misspelled word " Lucal 25D" on AliExpress. They do the kit for approximately 1/2 the price of Accuspark & mine arrived in Accuspark packaging for £22.

[martinclan56]

I am gradually picking away at a few of the smaller "to do" things when I get the odd hour to myself.

When rebuilding the engine it was obvious that the distributor was well past its sell by date so I purchased a new (Chinese Lucas 25D clone) replacement from Powerspark. This is an electronic distributor using a hall effect sensor and was responsible for the difficulties I had when first starting the engine. Partly my fault I should say to be fair. However that was soon sorted, but it led me to investigating the distributor further. The Powerspark distributor is supposedly a direct replacement but when I investigated further I found it was pretty unlikely that it had the correct advance curves.
A bit of deep Googling and I found that there are dozens of types of 25D each with a different mechanical and vacuum advance mechanism depending on the engine it is for. Ahh...
The mechanical advance is determined by the cam plate and springs. The vacuum advance depends on the vacuum advance unit fitted. After a bit more investigation I found that Distributor Doctor could supply new springs (not cheap) and I managed to get the correct cam plate (10deg) and vacuum unit from Ebay.
So now I have an almost new "proper" distributor.
dizzy1 by Robin Martin, on Flickr
You can see that 2 quite different springs are fitted. The lighter one is responsible for the initial slope of the advance curve whereas the heaver one takes over part way through the rev range and controls the second part of the advance. The total advance, 10deg at the dizzy and therefore 20deg at the crankshaft, is limited by the camplate. It's all very clever.....

While I was at it I also repaced the little wire that connects the points to the outside world. This has to be super flexible to allow for the movement of the points plate when the distibutor advances and retards. I used multistrand silicon insulated wire normally used for the leeds of multimeters. Only time will tell if it is up to the job.
dizzy2 by Robin Martin, on Flickr

[Ye Ol Ripper]

Hi Robin . Eventually I will get around to replace my 2 pancake filters with a fabricated airbox . However I used some approx 2" flexi trunking from behind the front grille and routed it to blow cold air just in front of the front carb as that gets hottest first. That was sufficient to overcome the vapour lock issue.

Louvres may look better cut into the top of the bonnet , Like a Caterham 7 uses, rather than a scoop. However that's a personal choice for you to make as all Marlins are different.

[martinclan56]

Yes. I realise I need to get some cold air in. Unfortunately my radiator fills the nose cone with almost no gaps. So I am contemplating a scoop in the bonnet. Just don't want it to be too ugly!

[Ye Ol Ripper]

Sorry Robin but I don't think that air filter arrangement will be ideal because the air filter is at the bulkhead end and there will be a lot of heat in that area under the bonnet. The problems will be most apparent on a very hot day when the power will drop off dramatically.

Potentially it could work as is, with either bonett louvers or alternatively running a cold air feed flexi trunking from the gap above the radiator and under the nose cone.Then running the Flexi trunking along the drivers side and pointing at the foam air filter.

[martinclan56]

I had intended to paint the rest of the car in September but the other half has rather inconveniently broken her ankle big time. It's very debilitating - no weight on it at all for 6 weeks and then very limited for a further 6 weeks - so I am now chief cook and bottle washer (and nurse) for the foreseable future. Ho hum.

However I have managed to spend the odd hour here and there in the man cave, and have been doing a lot of thinking! As a consequence I have completed something I would have done later which is a decent air filter arrangement for the twin SUs. It's quite difficult to acheive on the Marlin as the front carb in particular sits so close to the bonnet side. As a consequence most cars either have no air filter at all, use horrible pancake filters or have a huge hole cut in the bonnet side and top.
Anyway - enough words - here are some pictures.

air_filter1 by Robin Martin, on Flickr

air_filter2 by Robin Martin, on Flickr

To say I am pleased with the result is an understatement :-)

I did have to relieve the return on the bonnet side which is there for stiffness. But I have replaced that with another piece of ally angle about 5cm down. Still held with clicos in this picture.

air_filter3 by Robin Martin, on Flickr

[martinclan56]

It's alive.....

Click the its_alive link adjacent to the picture for the video.

its_alive by Robin Martin, on Flickr

[martinclan56]

Engine installation now complete and I have a working clutch. It's a long story but the main problem was the release bearing which was the wrong size.

Yesterday was a big milestone as I turned the engine over on the starter for the first time and established that I have good oil pressure. Always a fearful moment particularly as the engine hasn't been used for many years (20+) even though it had been rebuilt.

I have also now fitted all the ancilliaries and all the cables and pipes. Even with a simple engine like this there is a lot of plumbing.... The next step is to double check the timing, rig up a temporary fuel supply and fire it up. What could possibly go wrong....

A few pictures of the completed engine install.

Traditional SU HS4 carbs. Still thinking about how to add an air fiter as there is very limited space between the front carband the bonnet. Home made heat shield to hopefully aleviate fuel evaporation.
engine_lh by Robin Martin, on Flickr

Accuspark distributor (Chinese hmmmm) and tiny Denso alternator. HT leads need a bit of tidying up and I am probably going to fit some right angle plug caps.
engine_rh by Robin Martin, on Flickr

Completed exhaust system. I had the section with the flexi, which joins the manifold to the silencer, made from a drawing. Always a tricky thing to do with a 3 dimensional object like an exhaust. But it fitted after a little fettling. It looks a bit low but at the current chassis height there is about 5 inches of ground clearance - the same as the sump.
exhaust_complete by Robin Martin, on Flickr
exhaust_connection by Robin Martin, on Flickr

[martinclan56]

So a bit of investigation and much discussion later resuted in pulling the engine to investigate the clutch issue. I had used a NOS clutch cover, plate and bearing, but to be on the safe side I have now purchased a new boxed set of the 3 components. The clutch plate and cover are completely different in appearance to the NOS items but probably similar in function. The bearing however is a different story. The bearing I originally installed, supposedly the correct item, was 16mm high. The new bearing is 19mm high. I have since put everything back together and refitted the engine and am pleased to say I now have a clutch that works!


nos_vs__new_clutch1 by Robin Martin, on Flickr

nos_vs_new_clutch2 by Robin Martin, on Flickr

clutch_bearing by Robin Martin, on Flickr

[martinclan56]

With a little help from a like thinking friend the engine complete with gearbox is now fitted. 4 hands and 2 heads are better than 2 hands and 1 head! I first tried mating the engine and box on my own and failed - it is a heavy old lump.
Everything pretty much fits as it should other than:
1. I am a bit concerned about the clutch operating lever which doesn't seem will have much travel. About 2.5cm before it hits the gearbox. Don't think I cocked anything up but it does seem a bit "not right". See picture.
2. And the gearbox just touches the transmission tunnel side in one place so a little fettling will be required there.
Both the steering shaft and the alternator (not in picture) are fine with a huge 1cm clearance :-)

engine_in1 by Robin Martin, on Flickr
engine_in2 by Robin Martin, on Flickr
clutch_lever by Robin Martin, on Flickr

[martinclan56]

Robin, your build is exquisite in every detail. A real credit to your skills and vision! Can’t wait to see the finished article. Quick question if you don’t mind! What have you used for your bonnet/scuttle rubber tape and where did you get it from? Thanks and keep the post coming!

Thank-you :-)
The flat rubber tape is similar to the original. It was a while ago I bought it but I think it was from woolies-trim.co.uk.

[C_Bogue]

Robin, your build is exquisite in every detail. A real credit to your skills and vision! Can’t wait to see the finished article. Quick question if you don’t mind! What have you used for your bonnet/scuttle rubber tape and where did you get it from? Thanks and keep the post coming!

[martinclan56]

It's been a while since my last post but things have moved on. The Marlin has moved from my man cave to the garage (thanks to help from Peter) ready for the engine installation. And I have a real wheel in each corner. Just waiting for the inevitable few forgotten items to arrive now and the engine will be ready for fitting. In the meantime I have been fixing the Pembleton (see my other build) and have started painting the body - pictures to follow.
in_garage2 by Robin Martin, on Flickr
in_garage1 by Robin Martin, on Flickr

[listerjp2]

This is absolutely the last thing that I will do now before moving the car from my man cave to the garage to fit the engine.
I chose and fitted a Spal push fan to assist the radiator in its job. They are relatively expensive, but as they say, you get what you pay for and much cheaper than a new engine! There are unbranded fans arround for as little as £20 but I came across a comparison of a cheap fan against the Spal - there was no comparison!
The spal fan is also only 50mm thick making it a perfect fit in the Marlin nose.
radiator4 by Robin Martin, on Flickr
radiator5 by Robin Martin, on Flickr

That looks perfect.