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This is a read-only archive of the old Madabout Kitcars forum. New posts and replies are no longer possible, but every thread is still here to browse and read.

Engine rebuild 2.5 to 2.8 ltrs

10 Jan 2008, 7:04pm

M20B25 piston test fitted with M20B20 conrod and M52B28 crank! Moves well.

Piston / conrod / crank combo at top dead centre - looks good :)
11 Jan 2008, 11:03am
You think that's good - wait until you have them all in and then give it a spin - it's hypnotic... :dizzy: :D
15 Jan 2008, 8:43pm
Its going to need a thicker head gasket that standard. Still trying to figure out much bigger at the moment!


Crank spacer taking shape on the lathe

One step left is to machine down the spacer to the correct size - about 18mm
16 Jan 2008, 8:11pm
I've finished the crank spacer:


Spacer machine down to size, about 17.90mm with in 0.1mm of the original.

Cam belt pulley test fit, this a very tight fit so it will need the "the tool" to get it back off again.

As the M52 crank nose it a bit longer than the M20 the washer in the front doesn't sit flush.

Washer in the lathe, need to take about 1.25mm off giving 0.1mm space between it and the crank nose.

Finished off and the edge smoothed off

Test fit of all parts on the M52 crank.

Comparison: M52B28 crank and the front and M20B25 at the back
19 Jan 2008, 4:36pm
Cleaned up all the pistons today, but managed to snap one of the piston rings in the process - doh!

Andy, the chap who came up with the conversion several years ago has recommended I use the standard head gasket with this conversion!

One more discovery after examining the head, its not quite straight - its warped ever so slightly towards the front where the thermostat sits. Check with a steel ruler, but to be 100% sure I used the lathe bed which confirmed it. Off to the machine shop with the head next week then!
20 Jan 2008, 4:32pm

Silver is so last month, so blue it is this time!

We used red hamerite on the exhaust plugs and those didn't discolour until we welded something on it - so it seams heat resistance enough!

The hammered blue looks great out in the light.

Oil pump disassembled and cleaned. It all looks fine nothing really worn so no need to replace it.

The parts slot right into place, covered in assembly oil. This stuff is thicker than normal oil and kinda sticks to everything. Should help keep everything lubricated on the fist run.

The filter element has a few hardended clumps inside it but nothing major!
27 Jan 2008, 7:57pm
Got the head back from the machine shop on Friday (the place in Southampton were very good and friendly (if a little bit odd), unlike the first place!), they took 4 thou off to remove the warp:

Starting a bit of valve lapping

2 down only 10 to go!

All the valves boxed up and ordered

Throttle body attaches here, its been ground a bit larger - more pictres to follow on that at some point

Valve springs - the larger one has shrunk 2mm over the inside ones and new springs.

All valve lapped in - a simple short sentance that will take you hours and hours, especially if you have pits on the valves like we did!

A nice mat grey colour is what your after!

The valves all have a nice mat dull finish on them as well.

Valve stem oil seals going on - a size 11 socket bit proves to be exactly the right size to push these in place.

One at a time the new schik valve springs go in, putting the colletes back on proved to be a very fiddly proceedure!

All springs now in place!

All cleaned up - the head needed a 4 thou skim to take the warp out of it.
28 Jan 2008, 8:17am
Bling! :)

Very nice. Going for a colour cor-ordinated block, eh? (You're doing the sportster blue as well, IIRC...)
28 Jan 2008, 8:22am
Yup, that and I was not impressed with the silver finish. Looked nice at first but looks kinda dull - I was hoping it would set to a nicer finish after running the engine! The head will say in Ali and the intake / rocker will say black / ali :)

I might pull the callipers off and do those blue as well seeing as the rush is showing through the paint already.

Thinking of doing the sump yellow :lol:

The e30zone guys didn't think doing the valves with the aid of a drill was a good idea but seems to have worked OK. Took all day doing it with a drill. We'd have been there all week if we did those by hand!
28 Jan 2008, 8:33am
Hey Patrick

That's a really clean workshop you have there - great for engine preparation and other stuff :tea:

Looking good anyway. Is that the first engine you have rebuilt? I find it is one of the most satisfying jobs to do.

Robin
28 Jan 2008, 8:45am
Thanks (that's my dad's work shop) :) I though it best to do all the head work inside. Won't be doing the rest of the assembly there as lugging the engine upstairs will be a pain in the back (and not back side this time :lol: )

Yup it's first engine I've rebuilt - I will be much relieved once it's running again!
28 Jan 2008, 8:50am
Patrick wrote:

Thinking of doing the sump yellow :lol:


Nah - CBS do some lovely hot pink enamel... That'd look fab... :D (Not)

Patrick wrote:
The e30zone guys didn't think doing the valves with the aid of a drill was a good idea but seems to have worked OK. Took all day doing it with a drill. We'd have been there all week if we did those by hand!


Yeah - I got a drill powered lapper to do mine. It attaches to the drill, but instead of just wizzing round and round it steps the speed down and spins about half a revolution one way, and then reverses. 20 secs in one position, move 90 degs and another 20 seconds in the new positon, and you're done. One of my better ebay purchases! :)

I remember doing an old rover V8 with my mate one time, and we didn't even bother using the stick - just stuck the valve in the port and then attached a cordless drill to the stem on the other side. Worked a treat!
28 Jan 2008, 10:20am
hmm, guess it would have been better to do it that way (I did alternate directions while doing it) next time... (maybe not...)
28 Jan 2008, 9:23pm

Camshaft inserted

New oil seal and o-ring for camshaft

Rocker shafts and rockers on their way back into the head - the head needs to be propped up so there is room for the valves to open as the last rocker needs the camshaft rotated to slide in. Also make sure the rocker shafts are at the right angle before rotating the camshaft otherwise its not easy to move the into the correct place.

Both rocker shafts in and the clips that hold the rockers in place. The spray bar as also been mounted.

A closer view of the assembled head

Everything now in place on the head, it just needs the rocker cover put in place to shield the inside from dust.
29 Jan 2008, 7:00pm
New parts! Conrod bolts, main bearing shells, big end shells, water pump, cam belt and piston rings.
29 Jan 2008, 10:00pm
Patrick wrote:
New parts! Conrod bolts, main bearing shells, big end shells, water pump, cam belt and piston rings.


And new front number plate :wink:
29 Jan 2008, 10:13pm
Well spotted! :D (also and air filter and oil filter for my E46 as its due a service in the next few months...)
2 Feb 2008, 6:49pm

2.8 crank installed in the block with new bearings, bolts are torqued up.

Crank spacer in place

Many hours later all the pistons are installed with new bearings, all moving parts have been given a coat of assembly grease - this is more sticky than normal oil so it should stay put until the normal enigne oil is circulated round the engine before first start.

Front cover plate in place with new oil seals installed.

Oil seal around the crank spacer.

Water pump installed along with the gear for the oil pump.

Bottom view of engine with all parts installed. New conrod bolts have been torque, then turned to the approated settings!

Blue sump! Just resting on the engine for photos.

Its not quite this bright in real life, the flash has given it a much strong blue colour!
2 Feb 2008, 8:48pm
Cool blue engine....

You'll need perspex windows in your side bonnets:D
2 Feb 2008, 10:16pm
I'm going to run rat rod style, no bonnet, no side panels :lol: :madgrin:
3 Feb 2008, 4:41pm

Final clean up and degrease of the head.

Mmm shiny! Also double check that the cam pulley is turned to the timing mark on the head.

Belt tensioner now also installed

Head gasket placed on the block.

Head placed on block ready for the head bolts to go in.

Bolts placed, these were all tighten up as per the Bentley manual and in the correct order. Its a 3 step process.

Everything bolted up, the rear oil seal needs to go and the sump bolted on.

Final thing was to install the cam belt - turned the engine over severa times and it all sounds good. No interference between valves and pistons from the sounds of it!
3 Feb 2008, 4:45pm
Good thread - keep it coming!


Andy, the chap who came up with the conversion several years ago has recommended I use the standard head gasket with this conversion!


Is that Andy the co-founder of E30zone, that lives in Parkstone, Dorset? When my friend had an E30, he acquired a few parts from Andy - he's a helpful and handy contact!
9 Feb 2008, 6:08pm
alackofspeed wrote:
Good thread - keep it coming!



Is that Andy the co-founder of E30zone, that lives in Parkstone, Dorset? When my friend had an E30, he acquired a few parts from Andy - he's a helpful and handy contact!


Andy Everet - not sure where he lives but he freelances for Total BMW and wrote the E30 Restoration book.


Rear cover plated attached to block, sump bolted on and the flywheel on read to be bolted. The bolts need to be tightened 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!
9 Feb 2008, 8:39pm
Looking good Patrick. I forgotten how much space there was before everything is in place!

Robin
9 Feb 2008, 9:12pm
Wow, it's like re-building the whole front of the car again...

.... but this time all the holes are really are pre-drilled........ :tape: