Bearings, rings, etc.

[Vertigo]

hi,

found some time today to continue stripping my 4AGE. im about to start cleaning it, but before i do, id like to go over the entire engine block and head with a fine tooth comb, to find out as much as i can about its condition. im not very good in this area . could someone tell me what i should be looking for on the bearings, piston rings, oil pump, etc. should i bother even taking the pistons off the rods, to check the rod bearings? id love to order all the replacement parts, but budget limits this. its not going to be a race engine, turbo'd, or even really thrashed hard (much..).

the head looks good, to my untrained eyes. is there anything i can do to check it without taking it into a machine shop for a measure and skim? and really, is there much point if it looks ok, seeing as im not going to be running it that hard?

[Dell'Orto]

If it wasnt overheated or anything, a quick check with a level to make sure the mounting surface is flat will be fine. Take it in for a skim anyway, more compression is awesome
If the bores have any scratches it'll need to be honed, or bored if they're big enough, and you'll want to measure the bores to make sure they are still within spec.
The bearings, just look for excess wear, it's quite obvious when you see the shells.
You should be able to find the tolerances for things like oil pumps and ringlands in the workshop manual.
Clean the bejesus out of everything before checking measurements.

[Vertigo]

uh oh.. is this as bad as i think it is?

damage to the gasket surface in the water inlets


closer look

[Flannelman]

it is damage, but probably not as bad as it looks.

if it looks like chunks of corroded material could fall off into the water gallery, remove it with a file. just be very careful to only remove corroded material especialy on the bore side of the gallery.

[Eddy1612]

if it was a 4k then it wouldnt be a problem at all.

but yea i think just file it back a bit, tidy it up and if you arent gona turbo the engine or do major modification then it should be fine.

It's more important to make sure the head is hard and level. So get it pressure tested and planned if you want piece of mind.

[rollaholic]

good example of why using coolant instead of straight water is a good idea

[evil_si]

that block will live again, if you were really worried about it you could devcon the water galleries to build them up again but i wouldnt worry about it at this stage

if you can get the block acid dipped thats aways a good move,
side note if you do that replace all the frost plugs,
and give the bores a good hone

im a fan of getting heads skimmed and crack tested,
tj heads in manukau is a good guy


cranks if they look good but with a few small scratchs i get polished
main and big end bearings are cheap so i always replace them
HDR in manukau do a good job polishing them

oil pump i just check that the gears are in good nic, havent picked up on each other or the housing big score marks in the housing arnt good

as rollaholic mentioned running straight water does that damage, and thats just the visable damage,

when using only water cavitation occurs on the cylinder bore casting inside the water jacket, small bubbles that expolde and cause pitting
the diesels i work with 50,000km of not using coolant can destroy a cylinder liner and leak water into the combustion chamber or the sump

considering they do 1.2million km before needing any work 50,000 is nothing and some do 50k in less than 6 months

[Vertigo]

just5 been doing some reading around the net on head gasket replacement, and came across this:

How do you know if you have a bad head gasket in the first place? Some of the telltale signs of a bad head gasket make it extremely easy to diagnose, while other signs make you get out special tools for testing. Depending upon where the gasket failure occurs on the gasket, you can have a large amount of coolant entering the combustion chamber, which causes billowing white smoke to exit the tailpipe, along with raw coolant (if the failure is severe enough).

well, when the engine was running, it certainly was doing this. i thought it might have been the piston rings, but now im not so sure. could he have effectively been running around with a blown head gasket, caused by this damage? if so, how can i prevent it from happening again? its eaten away a good 5mm down into the water ports, so if a skim is in order, itd be a fairly drastic one!

edit: there was no water/oil mixing when i drained the oil.

[Vertigo]

ok, just got back from TJ Heads (note: now located at 4a Glasgow Place, down the road from their old workshop). Ted said both my head and block have been overheated and are pretty much $&#$%. i could still skim them, put it in the car, and have it run, but theres no guarantee itll just blow its top one day. great.

anyone got a (good condition) 16v longblock for sale? :/

[xsspeed]

I have a 16V smallport for sale, but haven't taken head apart to check. Only looked at the cams.

Thread here: http://forums.toyspeed.org.nz/viewtopic.php?t=68203&postdays=0&postorder=asc&start=0

[Vertigo]

might indeed be keen. ill have a think and get back to you mate. is this from one of your 4 rollas?

[xsspeed]

lol yes...yes it is

[Mr Revhead]

i doubt the block would be destroyed by overheating
have top get pretty hot!!
usually the only things that ruin 4age blocks is con rod escapism!

[escortman]

i have a block smallport rods and pistons and a bigport head that was fully recondioned and i used it for 2months sitting in garage, just need crank then give evrything a tidy up