Micra Mini! Was 998 now lightened 1275!

[Lawrence832]

12th july 2015 update
Had the evening off Friday and Saturday free to play in the garage
Decided on the way home from uni on the bike that stuff it I'll do the engine change!
But only if I can get the engine out but leave the gearbox in!

Using precision mathematics I calculated that in order to get the gearbox splines out of the clutch plate I needed precisely 42mm of space

Measuring up I found I had about 50mm in total that I could move the engine/gearbox side to side in.

8mm clearance= not a lot and it made me work for it! Updating this now I probably wouldn't have attempted the change in that little time. I've sprained my wrist for doing up bolts too

Well then, photos! Bikes moved outside, mini inside
Working area

What's going in

Stripping down


All ready to come out, cams removed as they are the 1.3 ones and need to go back in the engine
Coming out

You can see how tight the space I had to work in! Really could have used another pair of hands too!

Gearbox all alone

Engine out and on the floor


Total time to remove engine completely and gearbox staying in = 4 hours
Started at 1800
Out and sitting on the floor by 2200
Left and at the pub by 2230

So that was Friday evening.

Cue Saturday morning started at 9, had to be done by six as girlfriend coming over and I'm cooking

Timing done and Cams installed by 10am

Gaskets all done, sump on and ready to go in by 12


Straps on ready to hoist in the car, pump the hoist and hang on what's that? And gap by the headgasket! Cylinder head has come off the block By a few mm!

Ahhhh
I had never torqued the sodding thing down before had i!

So I now have 6 hours to take it apart, torque down the head, put all back together and then refit everything to the car ready for work on Sunday!

Well that didn't happen.
To torque the head the sump comes off, timing cover, cams everything needed semiset gasket removed and reapplied. Took me hours and I was so annoyed with myself

Last photo so far
Engine finally in and reunited with gearbox

Went in lush and so smooth.
Engine at 45 degree angle, then flat to hovering just on the subframe. Slightly jacked up gearbox, pushed together but the splines didn't line up. Rotated engine slightly with crank pulley bolt. Tried again and they slipped together lovely.
Probably took 5 minutes tops

But by the time I had rebuilt the engine again the engine was in the frame by 1500!
So I had three hours to get everything back together. Well it didn't happen obviously
Writing this now everything accept the carbs and exhaust are done and dusted

I test fired with easy start. It's got a slow turnover but ignition so that's good.
Inlet manifold is fitted but no new gasket as I need to make it. Tested with my hand on the manifold and there's a big vacuum that end and puffs from the exhaust side

 

[Lawrence832]

Righ then, this is now all up to date. Need to put a limit of the throttle cable to counterbalance my heavy foot if I'm not careful!

The video finally uploaded. This is the one driving round a car park with some acceleration fun with pops and bangs

That was taken the other week

Today I decided to dial in my cams to make up for the timing change from the head skim
Filed the dowel down on the inlet, exhaust cam was still time fine


And refitted


On the micra when the engine is at tdc the inlet cam lobes on cylinder two should be pointing at the cam cap bolt. Mine was about 5 degrees retarded


The exhaust cam lobes on the third cylinder should also be pointing at the bolt on their cam cap


Dialling in the inlet cam has lowered the power band somewhat from about 5k more to 4k so has given more usable power

I also have checked the spark plugs and gapped them slightly more. Taking a run in her tonight she seems to be pulling nicer from lower down now but it could just be in my head. I've also tuned the megajolt to change the soft Rev limit up to 6600 while I'm getting used to the engine

Mpg wise I did a calculation and she's doing about 32mpg. That was only from a 50mile fill up and 10 of those miles were driving through the city banging her off the limiter to get fun backfires. I'm hoping that with some gentle cruising she will get at least 40mpg!

To do list
>fix constantly squeaking fuel tank, there's metal on metal contact somewhere and it's annoying!
>after pay day order new inner cv joint. Current one is making a nasty grinding noise at speed. Think the bearing have had it.
>the alternator whines! It's mild but annoying. Going to swop to my spare. Also going to make more effort in lining the pulleys up as I think that may be some of the noise too.
>new heat-wrap needed for exhaust. Again after pay day

That's all folks
Feel free to comment

Lawrence

 

[pollyp]

giggidy. fantastic documentation & fab work

 

[wehey]

Nice work
Are the pics of the cams taken before or after adjustment?

 

[Lawrence832]

Cheers guys. Unfortunately not. I got so engrossed with what I was doing and forgot. It was noticeable on the intake side that it was about 5degrees retarded. Driving her today she seems to want to pull a lot lower down and overtook lovely in 5th

 

[Lawrence832]

Hey then people
Micra mini does still exist but I've been so busy with the little beast that I've not really kept this blog updated.
I mainly wanted to keep the engine and mini parts separate so let's put a little update on about the engine.

Main thing.
1275 high comp engine is no more piston rings were on their way out which caused all sorts of problems. Then my radiator over pressurised and the headgasket went stranding me 30miles from home.
998is now back in with the lightened flywheel and 1.3cams

So let's do a brief update
August
Breakdown

Thermostat bypass hose split

Catch can for oil blowby

September
New fuel tank

Headgasket went

compression tested the broken 1275. Got 170.180.160.200 dry and 210,210,230,230 with oil down the bored so definately broken
998 refitted


October
All new front suspension bushed fitted and new shocks also

November
New alternator and mount made


December
New wheel arches for the new wheels


January.
Mot fail sheet as long as arm

Wideband bought

New stub stacks for carbs

New wheels and wheel arches all fitted



February
Parts for new inlet manifold with carbs at nicer angle

New engine mount

Better carb angles

Bit of poke


And that's a brief update
Currently adjusting engine mounts to make the new inlet manifold, hopefully withiut cutting the bulkhead if I can avoid that

That's the big bits I've done and loads of little things in between
Hopefully when the new inlet is made and the carbs set up properly using the dynojet needles and wideband she should drive lovely

She's got no mot currently so I'm back to the motorbike but it's all good as I've got so much petrol money it's amazing!

I'll try and keep this updated
Hopefully someone will like it
Lawrence

 

[Lawrence832]

time for an update
june 2016
new motorbike

throttle bodies to go fuel injection


nothing till august 2016
new front air dam, also projector beam lights


work restarted this year
new front mount radiator


mocking up the inlet mani


new water pipe design


pipework sorted


expansion tank spot chosen


manifold being fabricated


throttle cable sorted


gear linkage bearings fitted (as shown by one of you guys in their thread!)


manifold painted


throttle body wiring sorted


So thats now up to date.
Currently thinking about the feeling system as I need to adapt the return less supply that it currently has to a pressure regulated one.

Then I can look into wiring up the megasquirt!

Lawrence

 

[Lawrence832]

Hello again people.

I thought I would do a little update on how ive been getting on mini the mini micra


This is how the engine bay currently is




my to do list

>fit new coolant pipework

>finish solid coolant pipe

>redo HT leads

>Extend EDIS coilpack wiring

>Finish and paint rear engine mount

>Put engine bay all back together (must fit inlet mani gasket!!)

>Check fuel system for leaks

>Wire in megasquirt


Fuelling is all sorted now, I modified the original fuel rail however my welding wasn’t up to scratch then I warped it so had to buy a new rail





Cooling is almost done, just waiting on pipework


New alternator bracket made







Wiring need do for megasquirt


But shes getting there


Also ive redone all the suspension all round with new shocks and springs for the front. Refurbed at the back.



New front indicators and splitter made




so that’s her up to date on here J

Lawrence