Hello,

I bought myself a 20V Blacktop yesterday and today we decided to strip the engine and take the cam cover off.
Under the cam cover we saw sludge sludge and sludge all over. The bearings and cams seems to be okay, but i'm afraid to take the head off
What do you guys think? Return the engine or just check the bottom and when there's no damage to the pistons, rings, cylinders, etc keep the engine?
The oil filter looks very clear, so that could mean two things. 1) The bottom is good and no sludge over there or 2) (I don't hope so) the oil passage is blocked.

Well...here are the pics:

Engine complete:


Cam cover itself:

Underneath the cam cover:








Tomorrow we are going to put the starter and brackter back on and check compression. I think this is possible isn't it? Valves are closed now and inlet/outlet is open and plugs are out. Should've done that right away. before stripping it :S

My silvertop was similar, and I'm aware of plenty of others over here in Oz with similar stories. Seems they don't get a lot of servicing in their former lives in the far east!.

I pulled mine down and had it hot tanked - took a day or two to make it all shiny and clean. It measured up ok and I was able to put in standard size bearings and rings. Has held up for 20,000k of abuse and track days since then. There are plenty here who just pop them in as received and thrash them till they burst, as it costs a few $$$ in gaskets and parts to refresh them.

OVERHAUL time =D

got to think these engines are from the 90s and they were probably pulled in the early or mid 2000's and never drained of oil....some been laid on the sides, stored for years....thats how oil looks after years of no use.....gas turns to sludge also...so your fuel injectors are probably in need of a few days of ultrasonic cleaning....when u buy these old engines u want the shops to start them for u, should of took the oil cap off at the shop and you would of seen all that...now that u took it apart im sure they wont take it back so only choice u have now is full overhaul....gasket kit, bearings, rings and a full cleaning....if your mechanically inclined you probably can do a basic rebuild yourself if your not do as much as you can and have a machine shop do the rest....remember to keep track of all the shims and where they came from for re assembly

What exactly is wrong with it other then looks????? First, do no harm, nothing that will clog the pickup. It either all comes apart or let that sleeping dog lie. Forget the running with kerosene or engine flush **** that's more harm then good.
Yes it may have bad bearings & sludged up oil ring ports, you don't know, any clogged oil passages are very unlikely, but what actual mechanical problem/s are created from lack of oil changes and short trips & being parked with high underhood temps?
It doesn't necessarily need anything as of right now except regular oil changes and cleaning the cam cover & its parting line on the head and every place else that you've touched so those loose chunks aren't picked up.

I had the same issue w/ mine. I didn't do an overhaul as my main goal was just getting the engine in my 86 & running. I ran Castrol GTX High Mileage 10w-40 in it & changed the oil filter once a week for a month. Now I run Castrol Edge 5w50 & change the oil once a month. Only because I've yet to get some type of air element on there. The engine runs fine & has made many trips from San Diego to Los Angeles w/o issues.

Back in the day(in Oki).... LOL.. I used to get the free 4ages from the junkyard that came out of the 4 door FF corolla, under the valve cover was worse than that, many times. I just split the head from the block and steam cleaned them inside and out, oil the crap out of em, and go. some of the longer lasting blocks i got came like that from the J.Y.

For perspective, That car was raced every night, stop light to stop light, drifted it everywhere for 2 years straight. 14 engines, 2 trannies, 3 ring and pinions, A million sets of tires, etc, so on and so forth. Sometimes an engine lasted a month or 2, or a few hours.

My USDM ae86 has had 3 engines in the last 4 years. The first one, came with the car(blowed up, HG on backwards, cracked valves, overheated a million times), #2: I wanted to be cheap, bought a bluetop long block for $150. smoked like mad, melted/cracked ring landings. #3: Bought a 20v Blacktop from my friend for a decent price. Stripped it down and used the short block under a 16v head. It has been running well for 3 years now, and will prolly get rebuilt next year or so.

Long story short, It depends on what you plan to do with your car. If you just want to drive it and beat it up, clean that engine up, throw it in and go. If you want it to last a long time with the Famous Toyota reliability, you should rebuild it.

MisterJerk wrote:Bought a 20v Blacktop from my friend for a decent price. Stripped it down and used the short block under a 16v head. It has been running well for 3 years now, and will prolly get rebuilt next year or so.

off topic but how well did that engine feel and did you use a stock head gasket and cams with the blacktop pistons?

today we've measured the compression number
Here they are:

Cylinder 1: 5 bar
Cylinder 2: 2 bar
Cylinder 3: 10 bar
Cylinder 4: 4 bar

we can measure the right compression without the cams in it, isn't it? We think that won't matter at all, but what do you guys think?

Thanks!

Is that compression wet or dry?
If dry, then you could have high leakage from either valves, rings, or both.

You need to oil the cylinders and repeat and get numbers.

This will tell you if you need to pop the head and do a valve job.
I would imagine that if so, it will be time to do a thorough cleaning of the whole engine.

At least that way you know what you have and what needs to be replaced/repaired.

ga_goosh wrote:

MisterJerk wrote:Bought a 20v Blacktop from my friend for a decent price. Stripped it down and used the short block under a 16v head. It has been running well for 3 years now, and will prolly get rebuilt next year or so.

off topic but how well did that engine feel and did you use a stock head gasket and cams with the blacktop pistons?

Sorry to jack the thread..

Currently I have a big port, light p&p head, shaved 0.5mm. 0.8 trd HG, stock cams. BT Pistons,rods, & crank. ae92/ST oil pump. Response is amazing, again timing is not advanced as stock due to fueling. Though i have bcpr6 plugs in it. Runs really strong. feels alot stronger than it did when i test drove the engine as a 20v. I think i screwed up the joggles when i cleaned em up some and Im going to just do some bowl work and clean up the exhaust ports on my spare stock head, and no shave.

Previously i had a stock big port head on it. felt like a super strong hicomp. but had to retard timing, due to compression and stock fueling. After installing the p&p head, the exhaust note sounded smoother and she got alot louder.

TRD 0.8 HG under both heads

Mod List:

Stock ECU and wiring harness.
Deleted EGR, electrical idle up.
20v FPR- disconnected vacuum (idled like **** with it connected)
Timing set with jumper to 5* advance.
BT 20v block with pistons, rods & crank. ae92/st style oem oil pump(16/20 with 20v oil pump and tensioner dont work. the tensioner is too short)
toda 3.7 flywheel, stock(exedy) clutch and pp.
pacesetter header.
stock cat
RS*R exmag2

it aint much, but for what i have in her she is amazing!

I don't know how you could measure the compression without the cams in - you need the intakes to open to get some air in there in the first case!

No, you can't get a valid compression number without cams, and you can't even get an accurate comparison between cyls. if the gauge is screwed in when the pistons are at different positions.
Those numbers are still pretty wild, no telling if there's an actual problem or just smegma on the seats of an engine that's been sitting a while or carbon from the spark plug threads when removed.

And we have been n00b's with testing! We left the oil filter out

The oil was everywehere. But the head is of and the bottom end looks pretty decent and not so smudgy at all.

Think the head needs a rebuilt, but first a thorough cleaning. We think the valves are sticking.

I made pictures of the camshafts and journals and put them in album with imageshack.

What do you guys think? I've never rebuild a car, but it looks like the camshafts and journals are worn.

http://imageshack.us/g/1/10034558/

The cam journals look OK.

As for the cam lobes, that's a little harder to tell.
From the photos I would say they seem to be in pretty good shape.
I don't see any surface fretting or undo wear on the nose of the lobes.

If you have a decent micrometer of the anvil depth to measure the lobes (nose to base circle), then do it on the lobes and record those values and look for dramatic differences in dimensions.
If they are close, then the cams are usable.

We think the valves are sticking.
Any particular reason why, other then the loopy compression numbers? How do they sound when tapped with a hammer? Obvious spring action & sharp click from the valve returning & hitting the seat?

Yes it has a sludge problem. No it doesn't have any other problem that you'll be able to see unless it's completely disassembled, but it sure may develop a problem from you F'ng with it.

I've added some additional pictures to my album.

Did make pictures of the crankshaft bearings and hone marks in the cylinders. I don't think this looks bad at all! What do you think?

Maybe i can do a little rehone without changing piston rings, do same head work, entirely clean the mess up and drive!

Overall, this engine is pretty good for the sludge.
How was the sludge in the pan?

I think given the slight rust in some of the bores that if you hone you will need to get new rings.
I think that the pistons are usable "as-is" with a thorough cleaning.

Given that the bearings show a little "witness" on them, I think maybe take the crank to a machine shop and have them micropolish it.
The bearings overall look good, but be sure to plastigauge them aftfer the crank work on reassembly, and do not hesitate to exchange them betweem locations if necessary to get consistent clearance on all journals.
Use a GOOD assembly lube when you put it back together.

s24a wrote:Overall, this engine is pretty good for the sludge.
How was the sludge in the pan?

I think given the slight rust in some of the bores that if you hone you will need to get new rings.
I think that the pistons are usable "as-is" with a thorough cleaning.

Given that the bearings show a little "witness" on them, I think maybe take the crank to a machine shop and have them micropolish it.
The bearings overall look good, but be sure to plastigauge them aftfer the crank work on reassembly, and do not hesitate to exchange them betweem locations if necessary to get consistent clearance on all journals.
Use a GOOD assembly lube when you put it back together.

The sludge was everywhere! I've added new pictures of the pistons, connecting rods,crankshaft, short block, etc. You can see that there was a LOT of sludge everywhere. This engine must have used oil i'm sure. One bearing has too much wear on it, it's not much, maybe normal for an engine with approx 100.000 km on it, but i think i need to replace them. We think this engine had none or almost maintenance at all and has driven very short distances. The orange colour is also telling this.

The pistons itselfs look good (as far as we can tell with all carbon on it), but the oil rings are completely stuck. Maybe this is because of the engine hasn't be used for a long while or because of all the sludge or maybe because of both . Anyway the bottom end is getting rebuild. The cylinders itself look pretty decent, most of the hone marks ar still there, not as deep as from the factory but not bad at all for a 100.000 km engine. We've measured one upper ring of the 3th piston. Okay we didn't put it all down in the cylinder to measure it, but just only a few cm, but we've measured only 0.400 mm, while new is 0.250-0.350. Max is 0.950 so that's very very good! Hopefully tomorrow i'm going to a engine rebuild shop to ask what he thinks of the engine and what should be replaced.

When it turns out that 'only' the rings, crankshaft bearings and rod bearings hould be replaced, then we're going to rebuild it. If it turns out that there are more bad parts then i have to reconsider returning the engine of continue with it.

When we're going to rebuild it then the head, short block and oil pan are going for a special wash at the same shop together with the cams. I ofcourse don't want any sludge in the oil passages.

To be continued....

the head, short block and oil pan are going for a special wash at the same shop together with the cams.

That means you are going to clean it yourself afterwards, completely, nothing less then removing all galley plugs to run a brush through every one. No one except a racing shop on their own engines will really clean it other then externally, just so it looks nice from a distance. The head & crank plugs are a bitch, I'd leave them but make sure that the solvent & compressed air comes out as clean as it went in.

He´s going to clean all afterwards. He´s making a lot of 4AGE for autocross. He has also built a 4AGE 16V with 172 HP, which isn´t bad at all! So i´m not worried about that. I´ll use an air compressor with the camshafts to ensure they´re all clean.

Today my complete wiring and ECU came in, together with the CV Joints and also the oil pump, water pump, engine gasket kit, wires, distribituor cap, plugs, etc etc.

Only thing i forgot to do, before i brought the engine to the shop is to take note of the numbers. I cannot order parts now, because i need to know them

So after cleaning on thursday the first thing i'm going to do is order the rebuild parts and then hopefully next week the bottom end is ready already.