18R-C Rebuild. Cost of basic rebuild?

[LT2K]

Hi, I own a 1981 Toyota Celica RA40 Liftback with an 18R-C.
It misses at idle, so me and my dad have investigated it and realised it was my original conclusion.. The rings are worn and are in need of replacement. Should I bother with replacing anything else?
I don't plan on doing it up, just getting it to run properly as I'm going to chuck in an 18R-G in the future.
I know rings are one thing, and to do that I'll have to do all the gaskets as well.
Any help would be greatly appreciated, I have a tonne of places to get them and a couple places i'm capable of getting trade prices.

But if anyone could help by giving me a list of things I should do in order to get it as if it just rolled of the assembly line including prices.

Thank you. =D

[Omegaman]

this is hard to answer, until you open her up.
But, as you said, buy a full set of rings, gasket (sump and Head), compare prices for full 18rc gasket kit. It maybe cheaper to get a full rebuild kit.
Once dissasembled, check pistons and bores. i would Hone the bores, if no real deep scratching on them.
Maybe get the head shaved, this will give it a straight flat seal, when rebuilding.
Other things to look out for are the crank bearings. look for excessive wear, keep them in correct order. relace if required.
Thats a basic, fairly cheap rebuild. see how you go.

[thechuckster]

unless it's making horrible noises, I'd stick to as few changes as possible: hone bores, new rings, replace bearings only if badly worn, ebay gasket set.

If you wanted to go to town, then apart from crank linish and new bearings, there's the cam chains, chain tensioners and guides to ponder and then the money is telling you to buy something newer, cheaper and more powerful.

fwiw: ebay gasket kit = $90 plus del (clicky) and it's even in Oz.

edt: shim up the oil pump slightly to get more oil circulating past the worn bits.

[allencr]

What's the compression?

It misses at idle,
The rings are worn and are in need of replacement.
I don't plan on doing it up, just getting it to run properly
...things I should do in order to get it as if it just rolled of the assembly line...

A miss doesn't = rings, and stopping the miss & oil consumption in a temporary engine doesn't = a completely rebuilt engine.
Sorry, everything is contradictory so what do you need/want?
You could fix the miss, it isn't the rings, and throw in a can of some magic snake oil elixir.

[S. Lowlux]

.


edt: shim up the oil pump slightly to get more oil circulating past the worn bits.

Could you please explain how we shim up the oil pump please chuckster ? Do you mean the relief spring ?.

[thechuckster]

yup, just increases the top pressure limit of the oil system.

[river]

Hi,

If the rings are worn so much so that idle is affected, then she must be blowing a shite load of smoke out the exhaust when she's under load?

seeyuzz
river

[Dazza]

Check the valve guides for wear and valve stem seals. The valve stem seals go hard with age and wont seal properly if there is a bit of sideways movement between the valve and valve guide. When this happens you can get a build up of carbon on the valve as the oil gets baked on which can make your valves leak. Also check that your inlet manifold hasnt warped so it doesnt seal against the head. The inlet manifold is bolted to the exhaust manifold which can get it hot enough to warp.

[LT2K]

My dad thinks the engine is a little bit smokey but I haven't seen it blowing even the slightest amount of smoke. So you could be right in saying the rings aren't buggered. I was going to go with the valves next. Could be a cheaper problem to fix than I originally thought.
Thanks.

[o_man_ra23]

Ok, I would start with this procedure:
Compression test. If the cylinders are even, leave the rings.
Put in thick oil. Penrite "stops oil burning" 30w70 is the go.
Take of the intake and exhaust manifolds, have them faced, replace the manifold gasket and re-install. From the experience with 18R-C's I have had, this is almost certain to leak.
Take the carby to a carby specialist and have it rebuilt. Trust me, it will be worse than you think, and a home rebuild just won't be the same. Get the jets checked and replaced if necessary.
Set the valve clearances.
Replace the plugs, leads, points, condenser, rotor button, dizzy cap. Set the points for dwell angle (point gap is close, but dwell angle is what you want to set) and then set the dizzy for proper timing.

I would only think about replacing the rings if the compression readings are all over the shop, or if they are REALLY low. Make sure you have all plugs removed and the throttle held wide open when checking the compression. This will give the most accurate reading.

EDIT: Just noticed you have that 32/36 (forgot). Have you had it re-jetted to suit the 18R-C?? I remember mine being thirsty as buggery when I had the 32/36 on 18RC combo. I got an 18R-G before it bothered me enough to do anything about it though.

[Rhyno]

Digging up an old thread here as I have been doing some research as my partner and I are considering buying one.

Lots of good info in here!

Did the OP end up getting the problem sorted?