home slap-together engine rebuild?

[Shifty]

I think a lot of people will be interested in this topic, I'm sure I'm not the only one who is/has been in this situation.

I have a CA18DET with a mild bottom end knock. Otherwise seems like a good motor, runs fine but obviously needs to come apart. What do I need to do to get it up & running as a throw-together? I want to spend as little as possible as it's not my project car, but want to get a few years out of it so I'll spend money as necessary.

Don't see the point putting another import motor in it, it will cost close to a grand and there's no real guarantee it won't shit itself in a few months anyway.

I'm ok with:

Block
wash
hone
deck
paint

Head
wash
machine
valve stem seals

Misc
New head gasket
Clean & reuse oil pump & pickup
Reuse/replace water pump as necessary
Gasket sealant/new paper gaskets as necessary
Reuse head bolts

Stuff I'm not so sure about...

Other stuff
Reuse pistons as long as it doesn't need a rebore?
Linish existing crank, new big ends & mains, replace if badly marked?
Rods, I have no idea?
Reuse rod bolts?

Any feedback/input appreciated. I have a general knowledge about this kinda stuff but have never done it before so I'm flying blind a little.

[oldcorollas]

bottom end knock?

pull off sump and check rod bearings with pistons still in block.
replace if necessary but make sure clearances are correct.

could do mains, but will need to drop the crank, but that would make it easier to measure the journals.

unless you particularly want to change rings as well?

tbh, you could just hon with wet n dry, linish journals same way, throw it back together and it will keep going for a while not ideal, but if you do it right, then it would be fine

[NME308]

Shifty - Congrats man - I'm glad to see there are people who understand the concept of import engines! The amount of times I've seen people grenade 3 or 4 import engines in short order is incredible!

Your proposed rebuild appears pretty good. I would add bearings and rings to the definatly replace list (if you wern't already going to).
Pistons will need thoroughly cleaning and inspecting to determine no damage or cracking before I'd put em back. If big end failure was caused by detonation piston damage could be present. That is of course all dependant on your observation of whether the cylinders need boring not just honing!

Considering the cheapness with which ARP or the like rod bolts can be obtained I would seriously consider adding them to the list regardless.

Add to that a decent torque wrench and remember cleanliness is next to godliness and you are on the right track already!

Cheers,
Jason

[punkture]

hey shifty, i am down this same path with the 3sgt, my stepdads an engine builder and told me for my budget (cheap) you still should get new pistons as the block should be rebored, he said the head fuck of taking the engine apart to machine head etc, is too much to not do the pistons. if your clearances are good though you may be okay. you will have to get new bearings, and more than likely theyll be larger or smaller depending on your condition

[Sciflyer]

Wynns Stopknock™

[BLK_20v]

I'm in the same boat with a 4age 20v. TIred of importers getting away with selling engines with worn valve stems / rings and passing them off as good.

Get a complete rebuild gasket kit, buy new rings and bearings and it should be good for many years to come.

[Shifty]

hey shifty, i am down this same path with the 3sgt, my stepdads an engine builder and told me for my budget (cheap) you still should get new pistons as the block should be rebored, he said the head fuck of taking the engine apart to machine head etc, is too much to not do the pistons. if your clearances are good though you may be okay. you will have to get new bearings, and more than likely theyll be larger or smaller depending on your condition

a fair point, but then it becomes a $3k engine build pretty quickly!

if the pistons are fine now, then the pistons will be fine later...all i really want to do is stop the knock!

[Phoenix01]

TIred of importers getting away with selling engines with worn valve stems / rings and passing them off as good.

It's not really uncommon for an engine that's been sitting around for months and months to have seals and other perishables to harden up and stop sealing properly. Sometimes they can come good again after a bit of use, other times not. In my opinion, picking up an engine with good seals and rings from an importer is actually just getting lucky.

[punkture]

a fair point, but then it becomes a $3k engine build pretty quickly!

if the pistons are fine now, then the pistons will be fine later...all i really want to do is stop the knock!

yeah as i said im in ur situation too..haha i know the pain, in my experience the 400 or what ever it takes to get a basic machining job, 130ish for the HG, 300-500 for the pistons isnt too much for peace of mind, ur rings etc may be okay now but who says 2months down the track youre going to find out that your pistons cracked? if your bearing is gone then theres a fair chance your engines been having a hard time, it also puts more priniciple stress on other components once your bearings go..

[kriso]

im curently building a CA18det at the moment but to produce a fair bit of grunt hence my rebuild is costing a fair bit more, but one thing i have found the arp headstuds are pretty cheap and readily avail on ebay i would def use new bolts as genuine items are a single use throw away item. I would by a full VRS kit so you have all the gaskets ready to go. When you have the sump off , pull of a main cap and rod cap and pop the bearing out, it will have written on the back the size of it and may have +25 or +10 etc, this will tell you if the crank has had some metal taken off allready or the bottom end line bored. If its done a conrod bearing i recommend a set of spool forged rods, there cheap and better then standard thats for sure. a set of ACL pistons wouldnt be to expensive either (or if the budget allows some cp forged race pistons are good choice ) A full set of kings race bearings is cheap too.

[Omegaman]

i would think new pistons are not for budget builds like this one.
If pistons are ok, just go rings.
New pistons in any build, would mean getting high compression one's and oversized, thus re bore.
But thats just me.

[briney]

did it burn oil ? i would be sorely tempted to check the balancer first. failing that, just whip the sump off and put some big end shells in it. jam it back in. do skids.

[checksix]

While it's together do a compression check. A better test is a blow down test, but if all you can do is compression, do it wet and dry. Little change between wet / dry is telling you the rings are good. Even compression accross all of the bores is also saying there is no one bad cylinder, but if the compression is low, then they are all worn and it would be worth doing a ring job while you have the rods off. I used to use a product called plastic gage long ago, this product might help you evaluate the clearances of the mains and rod berings. Try to unbolt the head evenly in stages if you can in the same pattern you would tighten in reverse. If done successfully, it will save you from having to have the head shaved. The head will only need removed if you are going to do the rings. You might be able to get away with only new rod berings, if the mains check out well with the plasti gage. Unless you drive the car hard, the rods and mains bolts will be fine.

[BLK_20v]

It is so easy to fall into the Oh it is only an extra 150 here and 200 there for piece of mind and before you know it you're up for an extra grand or so.

King bearings are worth looking into as well as they are cheap and good

[punkture]

It is so easy to fall into the Oh it is only an extra 150 here and 200 there for piece of mind and before you know it you're up for an extra grand or so.

King bearings are worth looking into as well as they are cheap and good

true but at least its better then the old 'hmmm whys it sounding odd? thats wierd i replaced the bearings only a few weeks ago' haha