I'm trying to come up with a budget for a rebuild of my A14 this spring. I've never rebuilt an engine before so I'm not sure what I should replace. I'd like to do 1.00mm overbore and a mild cam grind. The head has already been resurfaced, valve job and pressure checked. Here's a list of all the stuff I could replace when I rebuild. Can anyone tell me what's actually necessary and what's overkill? Or anything I've missed? This will be a daily driver.

Camshaft bearings
Connecting rod bearings (with oversize options that I don't really understand)
Crankshaft main bearings (also oversize???)
Expansion plugs
Timing set
Oil pump

All seals I assume should be replaced (rear main, crankshaft seal, oil pan etc).

Is there a way to tell if all of those bearings need to be replaced or not?

What about double valve springs? A set is ~$100. Is it worth it or necessary, or does it depend on the cam?

Last thing I can get $15 pistons which correct for the increased compression ratio due to the overbore, bringing it back down to 8.5:1. Sounds way too cheap to me. Any idea how much the compression ratio will be raised with 1.00mm overbore and stock pistons? It's an A14 with H72 head.

Sorry for all the questions but like I said I'm new at this. Really appreciate the help -
MIchael

The first thing to do is get hold of an a14 work shop manual. Mark everything as you pull it apart. As for going oversize with pistons & bearings. Take the motor in peices to an engine rebuilder & have him check everything out & they will tell you what to have to machine & replace & how much.
Follow the workshop manual with dismantle & assemblie & you shouldnt have a problem.
And also the manual will tell you what tools you need aswell

mperdue, i was in the same boat as you but picked my course headed off and now im more than happy with the progress done on my little donk!!
I have recantley had my A15 reconditioned (professionally done, ie not me!) with extra work: cam & crank grind, lightened flywheel, extra swirl on the head, 20 thou overbore, surfaced, honed, acid dipped and the usual...
So far i have fitted lifters, cam all new bearings, crank and bearing caps (i havent had much time to do this!) & am in process of fitting rings and pistons... All this cost me about $1200 (this was $800 for just a standard rebuild but i had extra work done)....better than 1500 that other places quoteed me.
And i have fitted/dismantled ALL of this with a B310 serivice manual, plus this is my first real taste at cars as im a newbie and NOT proud !!!!
But my 2c's worth are a fully reco'd engine with some head work, internal work, crank and cam grinds, 1 or 2 carbies (injection or whatever) will still be a great little fast car depending on the application you want it for..
But the serivcee manual will be the best 10 - 30 dollars you have EVER spent, it goes into detail you can only imagine and has everything and more you will need on reconditioning your A14.
But if it a daily driver a full reco would most probably be under about $900 if getting it done (this would most probably be not assembled so you'd have to do it yourself) and more extra work MAY not be needed depending on how you want it to go, where its going everyday...

Jsut remember, dont rush into anything, think it thru THROUGHLY and dont go flying you money here and there, ring up for quotes from many different places and tell em to stick it if its over about 1300...........

This is my experience which is quite limited so ask around here, everyone is keen to help people like you and me who are new to the buisness!!! Thats what the forums for!!!

Cheers
Dave

when i was having a 4pot rebuilt quoted, i was going to do the final assembly and they were going to dummy fit everything before machining, measure each piston individually before machining, do it properly and then hand it to me for re-assembly.

that was going to be $1500 AUS (about $1100 US) including H-E pistons and moly rings, polished and linished rods and crank, a mild cam and a ported head with bigger valves.

well worth it if you ask me.

I rebuilt my engine for less than $500 which included everything plus headwork. It helps when your family members are mechanics.

depending on how far you want to go really, it can be as expensive and detailed or cheap and basic as you like!

but basically if you go a full rebuild like datrat dave, its all new so not much can go wrong. Camshaft bearings shouldn't need to be replaced, connecting rod and crankshaft main bearings might as well be if you are rebuilding. the only reason you should need oversize items is if the crank has been scored (scratched, no matter how light it looks) usually the end result of a spun bearing. (oil lack causing friction). renew all the welsch plugs and yeah. new piston rings, and pistons if you are going an overbore.

if you take it apart and remember how it all goes back together (via the manual) then take the bits to an engine builder and see what they think in terms of oversizing etc. and get the machine work done then slap it all back together

It's all good advice, but to recap, here's my contribution.

Get the manual. DO NOT touch anything untill you get the manual. Read the relevant section as many times as it takes to understand what's involved in the next step that you need to take.

Try to buy the whole gasket & seal kit as one. This saves money & a lot of dickin' about buying separate parts.

For the extra dollar or so, buy brass core /freeze /welch [pick one] plugs. Always use brass ones in locations like the back of the head & behind the flywheel.

Datsuns will wear in the bore, but the crankshaft is almost bulletproof. If the engine has oil in the pan, you won't kill it, but if the journals do prove to be worn, then these surfaces will need to be ground down to the first undersize. The bearings that go with the re-sized crank journals are thicker, & are often refered to as oversize. You put the correct oversize bearings to the undersize crank.

Just follow the book & you will quickly determine wether you will be able to go the more economic route with a major overhaul [quite likely] or if it is too worn, then a total recondition may be needed, but if it runs OK, but is just a little tired, then the overhaul could be the go.

What's the diference?
Major Overhaul = Return all clearances & mechanical specs to within "service" limits.
Recondition = Return all clearances to within "new" engine specification limits.
Rebuild. This word is widely used to describe engine work,.. but what does it mean? It can mean just about anything you want as i have never seen a proper definition of its meaning.
"Rebuilt engine" is a phrase often used by charletans, crooks & other snake oil salesmen.

Thanks for all the replies,
I do have several manuals by the way (FSM, Haynes and Clymers). I've read through some of the engine rebuild sections and it looks simple on one hand but also it looks like it'd be easy to screw up if you're not careful. I guess that means I'll have to be careful.

One problem is I dont' have a garage. Can this be done outside? I have a place to store parts but just not to work. There's not enough space in the shed.

Any advice on the double springs or using the original pistons? Thanks again -
Michael

you won't need double valve springs with a mild cam suitable for an otherwise standard engine. A little 25/65 cam (or similar) would do nicely.

nine times out of ten, you won't need to replace the oil pump. The workshop manual will give you clearance limits for the pump which can simply be checked with a feeler gauge.

If you want to recondition the engine, it would be advisable to use oversize pistons. How far you need to go oversize will only be known after you (or a machine shop) measures the bore. But first o/s (normally .030" for aftermarket stuff) will more than likely do the trick.

As others said, get a workshop manual, and familiarise yourself with the procedure. When confident, disassemble the engine, take the block (with main caps in correct locations), crank, flywheel, pistons and rods to a machine shop for measuring and any machine work required. Then buy your parts (the machine shop will probably be able to supply the parts you need), and they will fit the pistons to the rods. Don't worry about any microscopic increases in CR due to o/s pistons - it's not an issue. especially with such a low CR to start with on the A14.

With the gasket set, if your head has been done recently, just get a bottom end set and a head gasket, manifold gasket and rocker cover gasket singularly. The VRS set (included in a full gasket kit) will not be needed and would just be a waste of money.

Other things not on your list that you should do while rebuilding the engine is a clutch kit and have the flywheel machined.

Also check condition of your water pump, hoses, and radiator as fresh engines run a little hot during run-in due to the increased friction while bedding in. So the cooling system needs to be in good condition to cope, and avoid the expensive consequences of overheating. There is a significant risk of cracking rings if a freshly rebuilt engine is overheated during initial run-in, especially if the most common black (aka cast) rings are used.

cleanliness is important while assembling the engine, so outside is not ideal. If you must do it outside, choose a still day (ie not windy) and hose the surrounding area down before you start to settle the dust. That's about all you can do to minimise the amount of airborne particles in the work area.

You will also need some specialist tools for the assembly like a ring compressor and a good quality torque wrench. An engine stand is a very nice thing to have as well, but it can certainly be done without one. Maybe see if you can hire or borrow one? They really make life alot easier.