Engine rebuild begins !!

[koos]

Picked up my engine on monday. Swopping a 86 325 in to my 91 320, putting the later fuel injection on, with a cam, a chip and hopefully a big bore throttle body. Stripped it down so far, all seems good. The white metal is starting to come off the mains and the big ends but not serious. Gonna fit new rings, big ends and mains and all the gaskets, water pump, cambelt, tensioner etc etc. Here are some pics so far. With my phone so a bit poo. Quick Q, what is the silver valve in the first pic?

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[img][img]http://www.imagehosting.com/out.php/i10 ... PA0042.jpg[/img][/img]
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[Turbo-Brown]

The valve's the oil pressure releif valve

[koos]

I thought that was in the oil pump?

[Ant]

PRV indeed !

Oil pump bolts to the shortblock , you can see two of the boltholes in one of those pix.

the pistons look to have shot rings judging from the blowby staining in the pix( in box) check the bores for wear, if there's none, measure the pistons, I've found a few that were oval.

Good project.

[koos]

Thanks will do, they looked okay. Comparing them to truck engines I've done, not car engines or BMW engines!! What valve is in the oil pump then? I'm gonna give it a hone aswell, I can still see the original hone marks in the bore and there is no ridge. Will measure it tomorrow. Thanks.

[Turbo-Brown]

That's a good question!

My guess would be that one regulates the oil pressure and the other one guards against overpressure.

[Jhonno]

whilst its in bit, lighten and balance the lot inc pistons and flywheel

[jeffwilk]

hi mate if your building a 325 engine why dont you use a set on bmw m52 pistions out of a 328 e36. you will need a machine shop to change the top but these are lighter and stronger than m20 engine so it will rev a bit faster.
jeff

[DanThe]

Agree with the piston thing, M52 pistons are already maxed out more or less on weight loss. Never seen them in an M20.
I have a set from an E36 323i if your interested.

Just got my crank gear back from balancing

[koos]

Right, heads going in tomorrow. Pressure test, skim and valve stem seals. Parts ordered for short block, getting there.....

[Ant]

Get the valve guides done too dude, almost defo neeed them on the exhaust side.

[ric325i]

thats pretty good to be able to tell all that from those pics Ant


experience i guess

[koos]

Checked the pistons and bore for ovalness, all seems okay. Painted the block today, looks okay. Gonna try a helicoil on exhaust stud hole on monday.

[koos]

Right, heads at engineer. GSF, the nobs sent me the wrong main bearings NOBS!!!!! And that was the last box, dont sell them anymore now? Getting some from ECP tomorrow, hope they are right.

Exhaust valve quides looked good as did the valve seats, just need to be lapped in.

[Turbo-Brown]

You had a chance to measure the waggle in the valve guides, better to get them done now than later

[koos]

Checked the movement with the valve in and it seemed close to nothing, general concensus in the workshop was that they're okay.

[Turbo-Brown]

Good schtuff

Lapping valves in is great fun!

[koos]

I know!!!!! Lapped in a 20v head a while back, its like watching paint dry, only with sore palms Needless to say, we now send them to engineering

[koos]

Update: Got the head back, all is well. It was a bit warped so they skimmed it, standard head gasket should be okay. No cracks, always a bonus. Started assembling the short block today, broke the oil ring on No1, NOB!!! Ordered another set, should get them on thursday. Other than that its going good so far, just washing all the parts.

Will get the cam next month, woohoo!! Getting exciting now, like a kid in a candy store.

[Turbo-Brown]

Oh the joy of installing rings! Have used Haynes method of destroying a set of feeler gauges in the past to geed effect. Only had one broken ring (ooh eeer) which was also an oil controol ring and that was broken when I took it out of the packet for some bizarre reason!