2.8 build

Post Tue Jan 15, 2008 9:58 pm

Looking good fella. Started mine today as my new crane arrived and managed to strip the block and test fit M52 crank. It does move well. Just after some M20 B20 con rods now.

Will start a thread of my own later.

Keep it up mate.

Cheers

Post Tue Jan 15, 2008 10:44 pm

phatz, if you still need to see the difference between single and double vanos cranks send templ8e30 a pm and he might send you a pic as he has both. waiting for another crank to turn up so we can get on with our builds. (mine is the single vanos one he has

)

jazzman, when i trial fitted the belt pully from the m20 to the m52 crank i noticed that the nose is slightly longer which would mean that the bolt tightens up to the crank nose rather than the pully if the spacer is made to the same size as it is on the m20 crank. wasnt sure if making it longer would make the belt pully sit too far forward causing problems with the belt in the long term, not sure what people have done in the past as i have seen no mention of it.

of course it could just be me as it was by no means an accurate measurement, just thought id mention it.

Post Tue Jan 15, 2008 11:00 pm

My plan is to make the spacer the same size as on the M20 crank so that the belt pulley sits in the same place. If required I plan to make a spacer for the front as well.

I'm still not clear on the head gasket thickness. The piston will sit right up on the head clearing everything which is fine. This means the thickness of the head gasket is pretty much all the clearance your going to get. Motormec to a +.3 gasket which is 2.05mm thick. I assume the gasket will crush a little bit when the bolts are done up?

Post Wed Jan 16, 2008 8:31 pm

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

Post Wed Jan 16, 2008 8:45 pm

Nice one mate.

Post Wed Jan 16, 2008 8:57 pm

That an Emco Compact(something) lathe Jazz? :lol:

Post Wed Jan 16, 2008 9:20 pm

Its an emco Emcomat 7

Post Wed Jan 16, 2008 9:40 pm

Thats in your house?

Post Wed Jan 16, 2008 9:46 pm

DanThe wrote:Thats in your house?

It's at my parents house (which technically was my house until I moved out - but I come back and use the tools and garage on a regular basis! Not enough room at my place to car building antics) My dad got the lathe many years ago

Post Wed Jan 16, 2008 11:21 pm

glad to see i wasnt imagining the difference in the crank nose length and also the solution is nice and easy to sort too.

Post Sat Jan 19, 2008 4:50 pm

Cleaned up all the pistons today, but manage to snap one of the piston rings in the process - doh!

Andyboy, has recommended I use the standard head gasket with this conversion, I've got one of those so that's all good to go now. The block needs to be level with the pistons so my need a slight shave.

One more discovery after examining the head, its not quite straight - its warped ever so slightly towards the front where the thermostat sits. Checked 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!

The other odd one, it seems in the past somebody tried to use super glue to seal the thermostat housing to the head - that was a PITA to get off!

Post Sun Jan 20, 2008 1:33 am

which ring did you break? i just broke an oil control ring putting mine back in and could only get a piston set. so iv got a set of SM top and 2nd rings here with no home for them.

Post Sun Jan 20, 2008 11:48 am

Bottom one same as you

looks like I'll have a spare set for middle and top as well!

Post Sun Jan 20, 2008 12:01 pm

oil controll rings are the easyest to break im afraid.

Post Sun Jan 20, 2008 4:50 pm

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!

Post Sun Jan 20, 2008 9:27 pm

Good work there Jazzman, and your block looks nice. Was contemplating spraying mine today, but decided against as I would rather get all trips to the machine shop out the way first, save any damage to new paint. You must be at a point where re-assembly can start, am I right?

Post Sun Jan 20, 2008 9:45 pm

Almost, but not quite, I've not ordered any new parts yet. I've got the list of all the parts I need now, but I want to see how much they need to take off the head to straighten it out so I know if I need to order a thicker head gasket! I'm also happy now that I don't need a new oil pump which is good

Once I have shells and new bolts the bottom end can go together. When the head is machined I need to so some more clean up and assemble it.

Just need a price for megasquirt from Ant and I'll be well on my way to a hopefully well functioning engine

Post Sun Jan 20, 2008 11:38 pm

i'm sure you can buy that filter or any part of the oil pump from bmw mate. It's not alot for that filter

Post Sun Jan 20, 2008 11:41 pm

Simon13 wrote:i'm sure you can buy that filter or any part of the oil pump from bmw mate. It's not alot for that filter

The two gears are around Ã‚£34 from bmw. The filter is pennies. For such a superb rebuild and attention to detail it would be frankly ludicrous not to replace the heart of the engine.

Just my opinion, otherwise very impressive!

Post Mon Jan 21, 2008 7:41 am

There's no damage to any of the parts other than some light wear so I don't see the benefit in replacing them. For me taking the sump off the bottom and replacing the oil pump is no problem at all as I don't have a steering rack getting in the way. So if I have problems with it I can always replace it later. I've got an oil pressure gauge so I can always keep a close eye on what its doing.

The water pump on the other hand is completely shot so I will be getting a new one of those

Post Mon Jan 21, 2008 8:26 am

i would replace the pump given you've rebuilding the thing just as an insurance measure.........you can't keep an eye on the oil pressure gauge at every second

Post Mon Jan 21, 2008 9:46 pm

Quick question on bolts, I'm replacing the head bolts with new ones, and the con rod ones.

What about the main bearing bolts - do those need replacing?

Post Mon Jan 21, 2008 9:48 pm

Mains cap bolts are not stretch, but at a cost of approx Ã‚£12 for the lot you ought to just treat it to new

Post Mon Jan 21, 2008 9:49 pm

Thanks Dan

Post Tue Jan 22, 2008 1:22 am

dans right, iv already looked into it and they say you dont have to replace the main cap bolts, altough there are pence even from the dealer.

Post Sun Jan 27, 2008 9:55 pm

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.

Post Sun Jan 27, 2008 10:03 pm

what is it about good clean head that gets me a little excited

looking good, should be quite a motor when finished

Post Sun Jan 27, 2008 10:57 pm

Looking good

Not trying to put a downer on things but you shouldnt really be lapping valves in with a drill, why didnt the shop do them?
I really couldnt be arsed!

Post Sun Jan 27, 2008 11:17 pm

The guy in the shop wanted Ã‚£500 to redo the head and refused to only do individually requested items. Lapping was done at very very slow speed so I doubt it would have had any ill effects.

Post Sun Jan 27, 2008 11:33 pm

You have some idle b**tards your way!

Place I use will lap valves in for about Ã‚£20! 24 of em

They do have a special machine for it though....

Post Mon Jan 28, 2008 12:15 am

Quite! I decided to do as much as possible myself. I'm sure the second machine shop would have done it but I prefer the idea of doing myself (well with a lot of my brothers help too

)

The cars not going to be a high miler, or daily driver - it defiantly a DIY project. There are easier ways to get more power such an M52 or M54 but then I wouldn't get the experience of rebuilding an engine

Post Mon Jan 28, 2008 12:40 am

DanThe wrote:Place I use will lap valves in for about Ã‚£20! 24 of em

60p a valve at the place I use. I've got better things to do with my life than lap valves, especially at that price!

Post Mon Jan 28, 2008 8:38 am

Brianmoooore wrote:
DanThe wrote:Place I use will lap valves in for about Ã‚£20! 24 of em
60p a valve at the place I use. I've got better things to do with my life than lap valves, especially at that price!

after a day of valve lapping I have no plans to do it again - at least there are only 2 per cylinder on the M20!

Post Mon Jan 28, 2008 10:36 am

on reflection, this device would have been better combined with a drill to do valve lapping (for those that still need to do this job):

Oscillating Valve Lapper

(I'll do it with one of those next time, or just pay someone to do it)

Post Mon Jan 28, 2008 10:01 pm

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.