Vrs + Piston Change

[VBlue]

Hey guys, my '90 AE92 seems to be burning oil, it's not really noticeable unless it's over about 5000rpm, but I know it is slowly burning oil especially when I'm on the motorways, it's not too bad at the moment, but I have to make sure I keep topping it up every few months, which is not ideal.

 

I'm guessing the head gasket maybe a bit faulty as well as the valve guides being worn and/or piston rings failing, etc. Would it make sense to purchase a VRS and change these parts out? How difficult would it be to do? My dad's telling me not to do it and that I'll screw something up. Can't really find a Youtube video on how to do it for a Corolla of this model (4A-FC/FE) which would have been nice, but I do have a manual...so you're probably asking why are you asking us if you have a manual? Well I generally find that reading something up and then translating that to actually doing it is a bit trickier, parts seem to be different, can't locate some thing and there are often problems that are not mentioned in manuals.

 

I also found 4A-FE replacement piston set, would this fit a 4A-FC? I'm guessing since the cylinder would be slightly bigger over years of use, I should have to order a larger size? Eitherway, I plan on doing a compression test soon and then removing the head and getting a measurement for the cylinder size so I will know whether I have to order an oversize.

 

Any info greatly appreciated.

Edited December 24, 2011 by VBlue

[ae824ate]

A compression test should show if your rings or valve guides are worn. Is there excessive blowby from the crank case breather or oil filler cap? If you do need to replace your pistons and rings, you will have to remove the engine, strip it, have the bores oversized and honed, and oversize pistons and rings to suit. While the engine is stripped you might as well replace the valve guides if they are worn, re seat your valves etc. It isnt a small job, and you will most likely find other bearings etc that are a little worn, and i usually feel inclined to get it all machined and get undersized bearings, so its all like new, not just one part. Either decide to keep it simple, or go all out.

[Trev]

If the cylinders are not worn then there is no point in going oversize, pull it down, measure it, if it measures up to be within specs then hone it if it doesn't then get it bored.

[VBlue]

I haven't checked for blowby, but I will soon.

 

I'm just wondering whether a rebuild kit like this one:

 

http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=360320374796&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en

 

for the 4A-FE engine, I didn't think the 4A-FC and the FE were too different, so it should be OK considering it's not a late model 4A-FE engine?

 

I emailed the seller, but he wasn't sure. I think it's simply known as 4A-F in the USA, so perhaps that's why.

 

Oh, and Merry Xmas by the way.

Edited December 25, 2011 by VBlue

[Trev]

4AF fly cuts in the pistons should be the same regardless if it is an E or C, compression is the only factor that will change the piston depth but they are most likely the same in that regard.

[VBlue]

Yea there is major blowby from the oil filler cap, removed the filler cap and when I turned on the engine, dad had his hand over it to check for compression and it threw up a decent amount of oil and continued to do so. There's definitely a sealing issue as I suspected. I can't do any machining so boring/honing the block is out of the question. However the parts aren't very expensive for a full gasket/rings/piston set. Is it something that a newbie could do alone at home? I'd definitely need to buy an engine stand and some other tools of course. By the book it doesn't look too difficult, unbolt this and that, remove the head, strip it down, use a gasket scraper, scrape off the gasket material etc. dismantle the rest, remove pistons, replace rings, etc. etc. Sounds easy enough, but is it?

 

The car was $1700, I don't mind spending a few hundred in replacement parts and other tools as I can learn something along the way too and get fresh new parts to last for a long time, but I'm guessing this would be an expensive labour job if I had to get it done by someone.

Edited December 27, 2011 by VBlue

[warrenfromtonny]

simple just drive it until it is dead then go buy another engine. hate to be frank but from what i have heard a rebuild may be out of your range, both price and ability.

Edited December 27, 2011 by warrenfromtonny

[VBlue]

Cheers, thanks all for the info!

[philbey]

You know what I'm all for you getting in and doing it. Sure you could buy another engine cheaply and swap, or you could do a pull down and rebuild and learn a shitload.

 

Before you do anything drastic though, compression test it. Oil flying out the cap is from the cams flicking out, not blobby. Its not a particularly useful method, comp test, then pull the head off if it's bad. Then you can better diagnose if it's the bores or the valve set seals. You might get lucky and the bores are fine, then just head rebuild and gasket kit, out of jail free!

 

First up be aware that this likely won't be as cheap as a few hundred. Do you have a torque wrench? Thats150 for a reasonable one? Engine stand and crane, there's 300-400. Your block may be knackered, there's a couple of hundred for the dip, bore hone etc, and then you'll need pistons, 200. Before long you will spend half the value of the car. Not trying to talk you out of it, but you don't want toget halfway through and the project stops because you didn't have the budget right.

 

If your keen to learn and have the money and time, do it.

Edited December 27, 2011 by philbey

[VBlue]

Yea, I might as well do it I guess. I'm hoping to do a part-time course in engine reconditioning, should hopefully get me up to scratch.

[VBlue]

Did a compression test today, got the readings as follows with around 5 cranks.

 

DRY:

 

1: 170 PSI

2: 167 PSI

3: 90/110 PSI (Cranked a couple of extra in a 2nd attempt for cylinder 3 as I thought I did something wrong initially)

4: 168 PSI

 

WET:

 

1: 190 PSI

2: 200 PSI

3: 140 PSI

4: 190 PSI

 

So the issue seems to be mainly with the 3rd cylinder. What should be my course of action from here?

 

Cheers