Ok, I need some opinions on this. First of all some history:

I got a jdm b16a 2nd gen, was burning 1/2 quart of oil every 800miles.
Got some buddy club 3+ cams, piston rings gaskets.

The car burnt the head gasket, perfect reason for rebuild.

First rebuild:
The mechanic: put new OEM 81mm piston rings, rod bearings looked fine but replaced them with ACL std (the colours of OEM were yellow-brown-green-green), milled the head 0,2mm, drop the cams in using the b16b valvetrain I already had, complete OEM cylinder head gasket kit was used.
Myself: turned the gear to +2 intake cam, tuned the A/F ratio to 13,2:1 and hit the road. I did a hard break-in (100 miles soft driving, change oil, beat the hell out of it).

The car was FANTASTIC compared to the previous state (MUCH faster , not burning oil) BUT:
600 miles after the rebuild the engine started sounding like a subaru imprezza! After opening the oil cap with the motor running, the engine had a HUGE amound of smoke, which wasnt normal.
I did a compression test and found very low compression in cyl no.3. The decision was to open the motor again. (I was afraid the valvetrain wasnt enough for the BCs and something had happened with the valves there)

Second Rebuild:
Found that the piston in cyl no.3 had an almost not visible crack between the two top piston rings and the compression was going down in the block from there. The mechanic said it was the OEM pistons fault (high mileage made them weak he said). I didnt like the explanation (I've seen OEM blocks being turbocharged at 100k miles and work for another 50k miles ++ in low boost). I found a used p30 piston along with its rod. The weird stuff starts there. I saw the ACL rod bearings (all of them) having A LOT of ageing marks on them (only 600 miles wouldnt do that if everything was ok). The mechanic insisted that water had gone on them (!!???! the engine wasnt broken for water to pass in the block) and a new set of bearings would make things OK.

Anyway, the new setup of colours if OEM used should be: yellow-brown-yellow-green. Of course the mechanic said he measured things and put again ACL std bearings. I KNEW something was wrong but didnt do anything at this time. We also changed the valvesprings to some SRP (if I remember correctly) they were VERY stiff compared to the b16b yellows.

6000 miles after the second rebuild, I'm doing a friendly race and at 120 mph I hear a very NASTY sound from the engine "fssssssssssss" a leave the gas and at 3k rpm hear it again.
Turn the car off, wait for 1 hour for it to get cold (it was a very cold night).
Then I tried to turn on the motor and for 2-3 seconds after it got running heard noises like metal things hitting and then it stopped. I knew it was the sound of bearings gone bad.
I toed the car to the mechanic's shop, had a fight with the guy next day and decided to open the motor AGAIN.

What we saw were ALL engine bearings BOTH rod and main being scratched and looked overheated. ALL of them. At that point I could find what could have done this.
The mechanic called the machine shop to come measure if the crank was damaged. The guy from the machine shop said the crank wasnt out of round after checking it with a tool and said that because ALL bearings were damaged it couldnt be from bad clearances, in his opinion the OIL PUMP had done the damage since I had never left it without oil being at top mark.
When we opened the oil pump it had many small lines/scratches on the gears.

We found a used oil pump from another b16 that looked from the inside in perfect condition. Put everything again in using NDC 1-2200 std rod bearings (??!! wtf, the machine shop said they are much better quality than ACL, couldnt argue since I'm not a machinist) and ACL main std bearings. Now the Main bearings OEM colours were: brown brown brown brown RED...
I Dont know if using ACL std size there is a chance of that red bearing being in spec, I also havent got a clue if using those ndc std size bearings the yellow-brown-yellow-green rods are in spec.
Since then I have done 3k miles (worrying every day that I will hear that NASTY sound again), the engine is NOISY (various metal sounds) but I dont know if it is the valvetrain and BC3+'s with their clearance along with my 60mm tubing handmade exaust that does this.

I would like some thoughts/opinions on this (especially from people knowing a lot about clearances and machining things).
I feel I'm driving a time-bomb. The car pulls fantastic but I want to get rid of the motor because I got a psychological problem with it. I would trade the motor with a stock b16-b18 anytime..

Am I being paranoid? Am I worrying too much? Dunno, I just lost confidence in that motor (and all mechanics and most machine shops)
How could ALL the engine bearings go bad? The oil pump? Ok , but why at the FIRST rebuild the oem rod bearings were like brand new even the high mileage? The pump got bad at the rebuild? Am I so unlucky?

Damn..

 

Sounds like maybe someone put the motor together a little too tight. Lines and scratches and **** in the oil pump mean contaminate, and my uneducated guess would be metal from your innards. Bearings should not have score marks, lines, streaks, etc. Nice and smooth they should be. And "metal" noises are a definite no-no. I think(and it's just my opinion) your "machinist/engine builder" put that poor little engine together incorrectly. Probably used an Ingersoll Titanium 1/2 inch drive impact to put your rod caps on That REALLY blows, man.

 

well I'm pretty sure he didnt use a wrong tool in order to put the rod caps because I was the one to put the correct torque setting on the tool read from the manual.

I dont say the above in order to "save" his ***, he is a total ********..

 

i would always put a new oil pump on after a rebuild. if he was a great mechanic/enginebuiler he would have told u to get a new one. also sounds like some of the bearings were to tight.if one is to tight and starts flaking and breaking apart it gets in the oil guess whats gonna happen to the rest of them. this is why alot of people learn to do things on there own. there are some great engine builders on here i would have one of them do it before it happens again. u get what u pay for. sorry to hear that it sucks!!!

 

My question is, if youre doubting your machanic's work not once, not twice, but THRICE, why the heck are you still going back?!

 

because it was his fault, he did the second and third rebuild with no money for labour, I paid only the parts (bearings, oil, oil filter, gaskets).
Of course I should have gone somewhere else from the first time, none of all this would have happened so I dont say I made the right choice in the first place

The explanation of one bearing flakes damaging the others seems reasonable..

I think I should have posted this in all-motor, not much traffic here..
When I did search, I found threads for spun bearings all over the forum


Modified by svistras at 3:51 PM 7/10/2007

 

btw I should also mension than in changing oil I found a grey thing exact the same as assembly lube on my magnetic drain plug. The thing is, there wasnt assembly lube used when changed bearings..

 

just an update, I opened again the motor and found ubnormal wear on the rod bearings (again).
I dont give this more than 1000miles before knocking again..

I wont spent time with machineshops etc, got a friend's b16a2 block from a year 2000 EK4...

 

would you post pictures of the bearings to see what kind of wear they have?

 

I threw them away, but it was typical for bearings gone bad, tri-metallic had become bi-metallic (the final coating had gone away) and had very small lines on them