Matt578

Did you get the 0.020" - 0.040" or the 0.030" - 0.070" Plastigauge kit nick? Whats the minimun clearance out of intrest?

silent running

I can only think in metric! But it measures 0.018mm to 0.045mm. I'll check what the target numbers were in a minute, but the big ends can take about twice as much clearance as the mains, something like 0.03mm for the big ends, 0.06 for the mains.

Glad I checked it all out though. Disaster has struck - my big end clearance on #4 pin was fairly roomy anyway, 0.045, but when I went to give it a trial spin on assembly lube, it kept stopping at a certain point. Bollocks! Took it all apart, and bugger of all buggers, there was a tiny little nick out of the bearing surface where I hadn't seen it, which had ploughed up my lovely shells!

So, one crank to sell on that needs either a regrind or taking the nick out, one set of shells wrecked and both need replacing!!! Anyone got a brand new crank that they want to sell me cheap?

Matt578

Thats a disastar! Do you mean that the Crank had a metal frag of some sort poking up that you did not see and when you spin the rod on the crank with the bearings installed its wrecked the bearings? Or there was a defect on one of the acl bearings and now its marked the crank?

silent running

No it was on the crank. Somehow a tiny notch was in it that had raised a tiny lip of metal. Soon as I tried to spin it, the rod went round so far, then hit a brick wall, presumably where the join between the two shells is. Like a prat I pushed it a little further. The bearing shells were all fine before fitting, I checked them over. I'm gutted - I don't know how I didn't notice that little nick in the crank!

Tim W

iTrader: (1)

At least you caught it now, rather than build the engine straight up and run it for it to go 'clank' first turn of the key!

silent running

Yes that's what I keep telling myself! Measure twice, cut once - as they said at school in CDT!

Atari Boy

Off topic, sorry but Nick, let’s face it at school, your motto was ‘measure once, cut twice’ not the other way around. Who are you trying to kid?

ZEN Performance

Sounds to me like you need to sort the crank rather than replace. You can stone and polish the journal, or if you have one use a bearing file which will take out the protrusion from the journal. You also need to be aware that plastigauge results require consistancy of application.

I would recommend you rescue the crank and put the money into a new modine!

TimH

iTrader: (11)

Is it worth paying someone to fully inspect the crank (and remove the protrusion) for peace of mind?

silent running

Well the thing is, although the crank measured up within spec, it was on the outer edge of things anyway. And in a way, although it's a bummer having to replace the crank, it will give me peace of mind that it's spot on and there is no 'weak link' in the bottome end.

I've got a few very small needle files that would do the job, perhaps even a tiny grinding stone that I have on my Dremel would do the job as long as I don't slip! The Plastigauge is tricky to say the least. One big problem is that the holes for the big end bolts have an internal sleeve to keep them perfectly aligned, so the two halves of the con rod don't just slide neatly on and off - in fact they're pretty hard to separate carefully - this disturbs the Plastigauge more than I'd like.

silent running

While I'm mulling over about what to do with my crank (I think I'll have a go at fixing it) I started rebuilding my self-ported and polished heads which I'd been putting off for a while. I took all the oil and water gallery plugs out, thoroughly cleaned everything, degreased the outsides and cleaned them up as best I could, then set about fitting the STi3/4 valvetrain.

Meanwhile, the next delivery from CDF arrived - hard anodised front pulleys and a set of ARP head studs.



One head done - spring seats in first, then a dab of assembly lube on the top of the valve guides before putting the valve stem seals on - a simply push fit. Next a smear of lube round each tappet bore. Place the spring in position, tightest coils at the bottom. The retainer then goes on top of the spring. Now comes the tricky part, more of which below. Once the split collets are in and the spring compressor released, that's pretty much it. They're ready for shimming.



Fitting the collets! The hardest stage of putting the valvetrain together (so far!) was putting in the split collets, which are two small metal pieces that make a sort of cup shape if you put them together. These are what hold the spring retainer, spring and valve in one piece at the top and are a pain in the **** to put in, until you've had a bit of practice. Once you have your spring and retainer in place, compress them with your compressor then use the winding adjustment to get them so the groove in the top of the valve stem is showing clearly. Then use a dab of assembly lube (could be grease I suppose) and two fingers to get first one then the other collet into position. Very carefully, wind the compressor back out again and release. The collets will stay in position on the end of the valve stem and the job is done. It does get easier with practice. I didn't find my magnetic tool or tiny long nose pliers any good for this. It was only possible with fingers.



An overview of the process, showing the large spring compressor I use. I did get a smaller one but it was very tight, and tbh I found it unuseable. The ones I AM using is the £35 Draper job that you can get at most motor factors. Pricey but it does the job and I'll sell it on afterwards.



Overview #1 of my gloss black STi-converted ported/polished heads. Masked everything off and baked the paint a little with a fan heater and 500 watt security light. Nice dry finish in about an hour!



Overview #2. I know it won't show oil leaks, but I don't care - it looks evil which is what I wanted! You can see the combustion chamber with the valves now in position.

silent running

Well I found an oil stone, some 1200 wet & dry paper, WD40 as lubricant and some 0000 steel wool. Between the three I've taken the lip off that nick (and another small one I found) and smoothed down around them. And yes I was careful not to let any wire wool debris get into the oil holes.

Trial fitment of one of my old rods with a pair of bearing shells, shows that each crankpin is fine, smooth rotation, no noticeable bumps etc. So now the whole episode has only cost me a bit of time and a set of big end bearings. I'd love to reuse my bearings but I can't take THAT much of a chance, not with one pair ploughed up.

trails

iTrader: (41)

block looks cracking painted black...bet you are glad to be moved forward with it

silent running

Yes I'm moving things on, which is good. The thing that spurred me on to fix the crank was the idea that I could fix it myself, and that a new crank even from the cheapest supplier, would be two months' worth of saving up - at this rate I might not even get finished this year, as I still need a Hybrid FMIC and a modine, the last two major purchases I need. As it is at the moment all I need is another set of big end bearings and another pair of head gaskets (had to resell them to get the old cashflow going!)

Tonight I'll be giving the block a last once over with the toothbrush and degreaser then it'll be painted silver. So silver crankcase, gloss black heads, hard anodised pulleys. Should look mean. I'm wondering whether to do the inlet manifold as well but it might end up looking a bit too much.

Matt578

Nick post up a pic of the plughed bearing

silent running

The bad news: ploughed up big end bearing - if you look at the one on the left you can see where the nick on the crankpin left a bare metal stripe in two places.



...And the good news: crank is now fixed and all four rods spin nicely on it with no discernible problems. This picture shows a rod (one of my OE ones I kept a set of) on #1 crankpin with bearings fitted. As before, the pink stuff is Redline Assembly Lube which has been worth its weight in gold so far. Crank rescued!

Matt578

That nick does not look too bad mate... How deep is it?

silent running

What, the one on the bearing? Well it goes into the metal layer underneath, but I don't think it's a question of how deep it is, more that it's roughened what there is there, if you get what I mean.

ZEN Performance

I can sell individual bearings as we sometimes replace single bearings on competition engines that are being refreshed.

silent running

New big end bearings are on the way. So today I got on with the final cleanup and paint of the crankcase halves, sprayed the bores with WD40 to keep them rust free. There are so many fiddly bits I used a brush on tin of silver engine enamel instead of a spray can. Here's one half after its first coat. Once they're both dry I'll see if they need another coat:

silent running

Bugger, my new set should be arriving tomorrow! Thanks anyway though Paul. You haven't come across an old 20G and a set of 550s that need a new home have you?

Optical

Enjoying the progress so far
Are you getting the block and heads decked/planed?

Looking forward to the head clearance setting part

silent running

No, they're fine. The gasket faces on both the block halves and the heads are flat already in every direction. I've used a steel rule, a long straightedge/level, and they check out fine, I can't even get my thinnest feeler gauge through. So in the spirit of not spending money where I don't need to, I've left it.

New big end bearings turned up today so I started assembling the crank, big end bearings and rods. Torque setting for the rod bolts, after moly lube had been applied to the threads and under the bolt heads, was 43 lb/ft or 58Nm:



Next job was to degrease the crankcase mating surfaces, then install the main bearings, with the special thrust bearing in the middle (#3) position like all early cranks. I set out the two crankcase halves, fitted the bearings with the aid of a few taps from a rubber mallet, gave the bearing surfaces a smear of assembly lube again (but not the underside of the main bearing shells, only the bit which will be in contact with the crank). Finally lowered the crank and rods into position, numbers 2 and 4 went down into the bores, 1 and 3 are sticking up still. Oil seals at each end go into place soon as do all the o-rings and seals that all need replacing in between the two crankcase halves. Couldn't resist giving the crank a trial turn before taking a break...



Crankcase block assembled using all new seals and a load of thinly spread Threebond 1215. All the big crankcase bolts torqued up to 58Nm. Forgot to put the gudgeon pin circlips into the little ends of the rods before assembly...shouldn't be too much of a problem at this stage though.



Close-up of rear crankshaft oil seal. How far in should this go? Once it's all installed, there will be a circular cavity behind the seal which drains straight down into the sump, or at least that's the idea. If this leaks, you get oil all over your flywheel and clutch.

silent running

Next job is to install pistons. There are a few things to watch out for, one is the gudgeon pin offset being opposite to rotation and the other main thing is gapping the rings. I used an old 92mm piston down cylinder #1 to put the top (thinnest) piston ring against. It showed a 0.25mm gap.



Next job was to file one of the ring ends to get it to the target ring end gap which was 0.45mm according to the Wiseco instructions and a bit of working out with the calculator. Here's an overview of the bore with the ring being tested:



Feeler gauge going in to check the gap:



It's a long and involved process, of filing a bit, fitting the ring back into the bore, measuring the installed with a feeler, taking it out, filing a bit more, etc. until it's right. Once I had it correct at 0.45, I took it out and installed it onto the top piston ring groove on the piston. It looks big here, but it will close up just right. Only another 7 rings to go! The 3rd ring down, the oil control ring, doesn't need gapping but the 2nd compression ring does. Interestingly though, Wiseco have put in an extra note about Subaru boxer engines, specifically showing how to fit the oil control ring differently to other engine designs. I like that kind of attention to detail. What I don't like so much is having to go out and buy a pair of circlip pliers instead of just using my long nose ones like with the standard circlips...

Matt578

If you havent already got them take a circlip from the wiseco's with you, my local halfords circlip pliers did not have a small enough end to fit in them,i ended up getting a set of needle nose pliers which are used for building small models with and filiing a small groove in them to hole the circlip in there steady.

silent running

Yes I did take one and noticed that the hole was too small. I'll do what you suggested Matt. BTW did you install all your pistons with the FWD/dot mark facing forward? And pistons 1 and 3 with the offset hole low and 2 and 4 with the offset hole high? Just I think I may have one weird piston...

Matt578

I was lucky, when my block was bored, alan jeffries offered to gap my rings for cheap so i jumped at the chance as its a tedious job as your finding out, so the person marked where each piston should go and which rings go with that piston, hence i had a no brainer Why do you think you got a funny pistons, tbh i did not see much difference in the offset.... but i was not really looking to much as it had all be done for me by alan.

silent running

Aha! The truth comes out!

Matt578

If someone offered to gap your rings dirt cheap wouldent you do it

That not a dirty thing so dont go getting execited

Matt578

Read this nick

RH and LH Piston? [Archive] -