80 replies to this topic

[maieth]

Okidoke. As expected, some great answers lead to some more questions :)

There will be some degree of interference fit in the bush/shell and then reamed to size.

One thing still concerning me here is that the cam liners are just too large. Still not clear on which bit is reamed. Are the liners simply pressed into their bores and them milled out to fit the camshaft perfectly? or are the camshaft bores milled out to allow the liners to fit? If it's the first option, there is no way the liners/bearings I have got are going to press into place.

one other thing I would point out is the honing, just to make sure before you put it all back together, did you supply the pistons so that the machine shop could hone to the correct size? how many miles had the engine done prior to the strip?

Engine was on about 65k and the block and pistons are in very good condition. Because of this the original pistons are being used and the bores have only been very lightly honed to give a fresh surface. New, standard size piston rings being fitted, based on machinist's recommendation from the amount of material he needed to remove (i.e. very little).
This sound ok?

From the above, you have missed a new oil pump, a set of oil gallery plugs & a timing chain.

Got the oil pump, forgot to list it. Not familiar with oil gallery plugs. I've searched minispares and it says they are only used on pre-1985 motors? (block is an A+ from 1999/2000). Core plugs have been replaced.
Is timing chain a useful, recommended or absolutely necessary change? This is one part I haven't got yet.

The block can then be returned to the machine shop for the block deck to be machined to bring the tops of the pistons to block deck level minus 0.002" to 0.005".

When stripping the block, pistons were pretty much flush with the deck at TDC. As the same pistons are being used is this step still needed?

You may or may not also find this of some help.

http://www.theminifo...-just-building/

Cheers.


Andy.

Andy, I must have read that thread 4 or 5 times end to end now. It's a fantastic guide that I'll be using for a lot of reference. You can add me to your list of grateful forum members :)

Edited by maieth, 17 April 2013 - 06:09 PM.

[Fast Ivan]

the liners will be a tight fit, they need to be pressed, probably using a hydraulic press, you wont be able to push them in, that said check again that you have the right ones.

only careful measurement with the correct equipment will tell you if the bores have enough material so that it can be honed. Its not a case of just getting them honed and fit new rings and away you go. the piston skirt gets measured, a clearance of piston to bore is established and the bore size can then be determined.

oil gallery plugs are definitely on your block, they are smaller than the core plugs.

the best way to tell if the piston to deck height is correct is by using a DTI. "pretty much flush" just isn't accurate enough.

hope this helps

[Dan]

Have the old cam bearings been removed?

[maieth]

oil gallery plugs are definitely on your block, they are smaller than the core plugs.

Thanks Rob. Anyone have a photo/diagram of where to find the gallery plugs? As I say, its not something I'm familiar with.

Have the old cam bearings been removed?

Yes. First engineering place removed them when cleaning the block

[Dan]

Look at the front and back of the block, the oil gallery runs from behind the front plate to behind the transfer gear chest. It's on what would be the forward side of the block when installed, just about level with the bottom of the cylinders. You will see what looks like smaller core plugs pressed into each end of it. You MUST clean the oil galleries properly. Hot washing isn't enough.

[Fast Ivan]

the location of the plugs. obviously there are some on the opposite end.

[attachment=141607:mpi block.jpg]

[johnnyblaze]

the 3 cam bearings will be of a different size to the next ie not all the same dia, this is so they fit through the previous cam bearing hole when installed, ie fitting from the front of the motor doing oil pump end 1st you have to get the inserting tool in through 2 cam journal holes so that means the oil pump end is the smallest the middle a bit larger and the front a bit larger again, we never honed my cam bearings and they were fitted in the engine shop in front of me.

Edited by johnnyblaze, 20 April 2013 - 08:20 AM.

[johnnyblaze]

the location of the plugs. obviously there are some on the opposite end.

[attachment=141607:mpi block.jpg]

mmmmmmmmmmmmmmmm 16valves, love the classic look the rounded bmw rocker gives

[maieth]

Thanks for info and pic of gallery plug locations, that's very useful. I'll check the at home, I think they are open at the moment from the big clean, so I'll get some pipe cleaners or similar and get to work cleaning them out properly.

Hoping to get block to machinist this week for the jobs listed over the last few posts. While it's away I'm going to get to work on the cylinder head and get stem seals replaced.

[Fast Ivan]

couple of things for the head - mark the valves so that you know where they go before stripping the head. check that the valves aren't to loose in the guides, the spec is in the manual, check the valve seats are not to badly pitted to establish if they need recutting. if your getting it skimmed then you really do need to establish your your piston to deck height (well you need to do this anyway really) the head combustion chamber voulme will change when you skim it and both of these along with some other factors will alter your compression ratio. Theres quite a bit of info out there on this so it would be worth doing a bit of research.

[maieth]

Work's been slowed on mine for a couple of weeks, as my wife's jet black decided to start mixing oil and water.  Spent the last couple of weekends getting her cylinder head off, properly refurbished and replacing the gasket. Looks like either that wasn't flat or we've got problems with the block. Fingers crossed it doesn't happen again, we're going to struggle if the engine has to come out of a second car.

 

Took my cylinder block to machinists at the same time for the last few bits of work and it should be ready to carry on now.  Cam liners were correct, and have now been reamed in.  Getting closer.

[maieth]

Right, finally made some real progress today. Got lots of the engine assembled, but i've hit my next stumbling block - questions at end of post if you don't want to read everything else.

 

Following Andy's guide carefully, the cam followers, camshaft have gone in. New mains bearing have been fitted, I gave the crank a fresh clean down and cleaned out the galleries, then got it put in place with the new thrusts and got the mains caps torqued down.  Crank was moving nice and freely.

This afternoon I moved onto pistons.  Checked all the piston ring gaps and clearances on the new rings (all great) and got these in place over the pistons, then started to put the pistons back in the block. Took a while and a bit of trial and error but I got them all in place.  Crank gradually got harder to turn, but I could move it.   All great up till now.

 

So I torqued up all 4 big end caps, and now nothing moves.  I know some resistance is to be expected, but nothing is budging with those caps torqued down.

Now, the 1st machinist (Who cleaned everything thoroughly) helpfully marked one side of each of the 4 con-rods and big end caps with matching numbers, 1-4, in the pairs and order they were received in.  However, I've already discovered that they marked all 4 on the same side, so as pistons 1 and 4 are reversed compared to 2 and 3, those are already marked the wrong way round.  With that in mind  I imagine it's possible at last some of the big end caps have been accidentally reversed, and I think I'm right in thinking this would cause some resistance and jamming, unless there's something else I could be looking at?

I want to have a look over the big ends later or tomorrow and check the caps are the correct way round anyway, so does anyone know a surefire way of making sure the big end caps are the correct way round?  Does the bearing locating tab need to face a particular way, for example?

 

Many thanks for all the help and advice so far. Still trying to do as much as I can, and getting a bit more help where it's needed.

Edited by maieth, 06 May 2013 - 07:53 PM.

[Jordie]

when u removed the big end caps (piston con rods) did you mark them to each piston and which way they came off?

 

you should have numbered them 1, 2, 3 4 etc and also marked only one side so they align back up.

 

Otherwise, you will get problems such as the engine locking once you torque up. You will now need to remove and turn caps and trial n error until you find the correct way. You should have oiled the bearings and crank whilst fitting the caps.

[maieth]

when u removed the big end caps (piston con rods) did you mark them to each piston and which way they came off?
 
you should have numbered them 1, 2, 3 4 etc and also marked only one side so they align back up.
 
Otherwise, you will get problems such as the engine locking once you torque up. You will now need to remove and turn caps and trial n error until you find the correct way. You should have oiled the bearings and crank whilst fitting the caps.

I oiled beneath the bearings and used graphene on the bearings themselves.

When I originally had the block and other components cleaned I refitted the pistons to the crank before sending it away, so they were kept in the right sequence, but didn't mark them up (stoopid). Machinist added marks but didn't appear to follow much of a pattern.
Trial and error is going to be the only way of getting them sorted I guess

[maieth]

Post removed - accidental double post.
Stoopid iPhone

Edited by maieth, 06 May 2013 - 10:37 PM.