Supra Forums banner

1 - 20 of 26 Posts

·
Registered
Joined
·
601 Posts
Discussion Starter #1
Well I spun a rod bearing on my engine. The rpm was way too low and the engine died going 40mph. So I put it into 2nd and dropped the clutch and the engine came to a grinding hault. When I try and crank the engine it moves one mm at a time.

What is the best way to access the rod bearings. I hear you can remove the oil pan and go from underneath? Won't the cross member need to be removed too for this and is the engine not attached to the cross member.

Help is appreciated. Thanks
 

·
Registered
Joined
·
1,418 Posts
whoa, i dunno, i've spun rod bearings, and i could still start and drive it, i think you did more than that.

pulling the pan (on an A70 chassis) only applies to the lower pan, which only shows you two cylinders i believe (3,4?), not to mention if you spun a rod bearing, you'll have to completely change the rod (and piston, and hone and re-ring) that cylinder
 

·
Registered
Joined
·
601 Posts
Discussion Starter #3
Does it sound like that could have caused me to spin a bearing? I was driving it and then the idle went all to hell and when I would push in the clutch the rpm would fall right to zero and it would die. I started it several times while moving at 40mph until one time it stopped the car completely when I dropped the clutch as if I hit the brakes hard.
 

·
Registered
Joined
·
601 Posts
Discussion Starter #5
That is the plan for tomorrow. I just need to know what could have caused this. Maybe because the motor is old? Also the last couple of days it has been a hell to start the thing. It would crank and crank and just barly try and start. Everything on the engine is new except the shortblock.
 

·
Premium Member
Joined
·
6,130 Posts
Hydrolock? Maybe blownheadgasket? was it smoking or anything? aight peace :chicken:
 

·
Registered
Joined
·
1,418 Posts
my car did that when the trigger wheel on the crank sprocket broke.

did you hear any knocking, or it just died? did you run it low on oil?

if it cranks over smoothly, but doesn't start, i'd check the crank trigger wheel.

i don't think it's the bearings

EDIT: check your compression and trigger wheel before you pull.
 

·
Registered
Joined
·
601 Posts
Discussion Starter #8
The block is seized, it won't turn at all. We had a 4 foot breaker bar on it and it wouldn't budge. The starter engages and ticks the crank about 1/16" at a time. So it does move but requires a hell of a lot of force to do it.
 

·
Newbe....I know nothing!
Joined
·
1,853 Posts
This sucks but start looking for another engine. When you push the clutch and the car dies it means there is ALOT of crank walk so much so that it is grinding the engine to a hult.

From the sounds of it it sounds like you have done one thing sezed the crank to the block or bent the crank so ban that its not turning at all. Rolling the car at 40mph and dumping the clutch to start it just to have the load stop the car is a lot of drag.

Jeremy
 

·
Not so boring anymore
Joined
·
7,085 Posts
find another engine.. that one is f'ed.. dont bother fixing it..
 

·
Registered
Joined
·
601 Posts
Discussion Starter #12
The head is okay. It just seems to be the shortblock. For a few days now it's been hard to start it. It would just crank and crank and give a little spit towards starting but not actually start. The oil pressure has also been low at idle too. Around 10psi but would go up to 50psi when I would rev it up. The night basically happened like this:

I was boosting about 16-18psi, 500hp to the wheels out on the highway. Everything seemed okay. I put it into 4th and was going about 210km/h ( ~135mph) @ 6400rpm then the car suddenly died. I had a friend of mine come and jump it and it took about 100 tries to get it to start. It would sputter and sputter until it would final crank over. Then on the 10 min ride home everytime I would push in the clutch it would stall. I started it while moving at about 100km/hr or 60mph about 4-5 times on the way home. Until one time at about 40kmph or 25kmph it stalled in 2nd so I dropped the clutch and that is when I realized it was seized completly.

I can now turn the crank little by little by hand. It seems to get really hard to turn at one point in the revolution and only kinda hard to turn the rest of the way.

Any other thoughts or opinions are appreciated.

I am kinda thinking that the block was weak with old age (100k miles) and it was it's time. My tune was dead on.
WOT 12.0 a/f.
19 degress timing @ 16psi with 110 octane.

Oh ya I had the first stall logged too:


A few seconds earlier:
 

·
Newbe....I know nothing!
Joined
·
1,853 Posts
Ok looking at you log I can see a big problem.



look at the A/F log there and tell that is normal, I see WOT A/F off the map and boost falling off at the same area. In that same area I see the RPM's start getting eratic. I think you had a big failer of some sort i.e. fuel flow or somthing along this lines.

Also 19deg timming at 18psi on only 110 is very scary.

Good luck,

Jeremy
 

·
Registered
Joined
·
601 Posts
Discussion Starter #16 (Edited)
Ya I noticed that too. It went very lean right before it stalled. I lost the input signal from the injectors for 120ms. That happened earlier that day too but only for 60ms and it didn't stall. It does that some time. The i/j input will be reading 90% and the output 50% then the both will be at 0% for 100ms or so. I don't know why this happens, I think my stock ecu is fucked.
Either way it is like the injectors all fail to fire for a couple revolutions. I don't see that being an issue.

The flywheel is an os giken.

I am actually in the process of switching over to an AEM unit now anyways. So the Emanage ultimate will be going.
 

·
Hardtop FTW
Joined
·
1,784 Posts
I was also going to suggest that you have crank walk.

I've heard of a few cases where this has happened on 1JZ's. The thrust washers are a weak point, and real heavy clutches, when the pedal is puched in, force the crank to move forward in the engine. Eventually the washers wear enough that the crank moves forward enough to catch and sieze the engine... It's not a pretty thing.

What clutch are you running and how long have you been running it? If this is the case the engine is pretty much trash. If you've got a 1J, it's time to start looking for a 2JZ bottom end. ;)

In the future, guys with heavy pressure plates, remove the neutral safety switch so you can start the car without pressing the clutch. Most of the damage is done on cold starts before the oil begins to circulate.

Collin
 

·
tunin' da beast
Joined
·
479 Posts
I noticed the same lean-out like TurboDrifter did. Was there any greyish coloured smoke at that point from your exhaust?

The symptoms to me sound like you melted some piston rings due to the lean out. It only lasted about 0.5sec but that would be enough at that load.

The part where you can rotate it a little easier would be at tdc and bdc.

Btw, why don't you log the injector dutycycle as well? You should have channels left to do this. I use the Greddy blue and use the same logging but I'd like to see what inj. duties I'm running. Might also want to use unique colors ;-)
 
1 - 20 of 26 Posts
Top