QG18DE rebuild project

[dani_kk]

Oh qamar bhai you've solved my problem. I was yesterday thinking about this.
I think i should go for nissan's original meter.

[dani_kk]

Well mine is not on can. It's simple jdm version with manual throttle and three row ecu.

And it supports iso 4120 protocol.

I have found the k-line wire, chk wire, di wire.
But two wires are still a mystery i think they are vendor wires.
Tx and rx i guess. As written on manual.

And to confirm the authenticity of that diagram i have manually configured every wire by digital multi meter. It had a continuity beep which tells which wire is it.
Even rpm is correct it's on 8.

Issue in that diagram is its in russian language. And other than that i literally have 1995-2007 manuals of all primera, almera, sunny, sylphy g10
But unable to find that.

The diagram i saw on pakwheels on someone's post was just showing supply diagram and it was written without euro obd and it had the same ecu three row one.

I'm waiting for my scanner to figure this out.

Elm 327 scanner is not working on these wires, it says set tester id failure.

[dani_kk]

And @sergtr maybe I'm confusing to things up
Bore is still the same as it was.
Only head facing is done.
I thought honing is also consider as shaving of the surface of metal using machinery so i thought you're asking in that way.
As we know bore size is 80mm
When we dropped its current rings in to cylinder, they were too loose were slipping inside as if there's no friction.

So when we dropped 90mm rings of Toyota 4AF
They were like 3mm more in diameter. They were very nicely trimmed and were brought to approximately 87mm. So currently my bore size is on 87mm. And piston rings were too of some Toyota I'll state u it's name too soon. But that piston pin is very heavy duty as compared to its genuine ring.

This could've been played better if i could get QG18de genuine pistons. It would have genuine diameter of pin so QG18de piston would fit in easily but since piston pin cavity currently was widened Slightly so con rod was having pley in it. Creating noises. So I've basically restored my piston to work as new piston with good compression.

And those were black bolts don't seem tty bolts. They were as good as new. No expansion at all in them.

[dani_kk]

Sorry i mean ISO 9141 AND ISO 9141-2

[dani_kk]

And I've built QG 15 and one QG16 and I've never replaced head bolts. Look we don't have accuracy here according to nissan bolt torque. Torque is nm means newtonxmeters
Force x distance.
According to my physics the length of rod he is using meets the necessity of rated bolt torque of nissan.
But they are never left loosened, never.

[dani_kk]

This is Pakistan bro's you guys are very right lack of technology and lack of finance. Even nissan service centres do not ensure about head bolt tightening torque. So we can't argue on that. Engine is driving good that's the main thing. These engines are like if they're built correctly they're gonna roll good if mechanic has left any bug this engine won't even start properly. So the guy who works on my car is very experienced. I've been going to him since i had Cd20d in my b11.

[IsbCap]

Maybe you can check Pin 21 for CEL

Will also involve IGN relay...

[Xulfiqar]

This is Pakistan bro's you guys are very right lack of technology and lack of finance. Even nissan service centres do not ensure about head bolt tightening torque. So we can't argue on that. Engine is driving good that's the main thing. These engines are like if they're built correctly they're gonna roll good if mechanic has left any bug this engine won't even start properly. So the guy who works on my car is very experienced. I've been going to him since i had Cd20d in my b11.

the reason the bolts are replaced is because they actually elongate when under tension - this keeps the head in place very tightly and every evenly and actually omits the "second tightening" of the cylinder heads which used to be a norm in engines from the 1960s

With TTY bolts - when they are brand new their thread pitch is even all the way and they have a set length, When they are installed and torqued up - they deform and the thread pitch changes where the threads are exposed - This is because the bolt has now stretched and is useless. If you try to reuse them there is a 50% chance of failure as the head is not bolted tight enough to the block and may warp when the engine warms up. I consider that very bad practice because a new set of headbolts are cheap compared to tearing down the engine again.

Some manufacturers do provide a spec length and service limit for the headbolts but till date I have only seen one or two actually falling into acceptable wear limit - almost everytime TTY bolts were scrap when removed.

newer engines even use TTY bolts on the con-rods - and when they let loose, kiss your engine block goodbye because the rod will shoot out of its side.

claiming that "engine is running" that is what matters is extremely shoddy. Specially when you know that the correct technique and replacement was not followed.

[saboor73]

the reason the bolts are replaced is because they actually elongate when under tension - this keeps the head in place very tightly and every evenly and actually omits the "second tightening" of the cylinder heads which used to be a norm in engines from the 1960s

With TTY bolts - when they are brand new their thread pitch is even all the way and they have a set length, When they are installed and torqued up - they deform and the thread pitch changes where the threads are exposed - This is because the bolt has now stretched and is useless. If you try to reuse them there is a 50% chance of failure as the head is not bolted tight enough to the block and may warp when the engine warms up. I consider that very bad practice because a new set of headbolts are cheap compared to tearing down the engine again.

Some manufacturers do provide a spec length and service limit for the headbolts but till date I have only seen one or two actually falling into acceptable wear limit - almost everytime TTY bolts were scrap when removed.

newer engines even use TTY bolts on the con-rods - and when they let loose, kiss your engine block goodbye because the rod will shoot out of its side.

claiming that "engine is running" that is what matters is extremely shoddy. Specially when you know that the correct technique and replacement was not followed.

Please shed some light on damper pulley with tty bolts

[Xulfiqar]

And I've built QG 15 and one QG16 and I've never replaced head bolts. Look we don't have accuracy here according to nissan bolt torque. Torque is nm means newtonxmeters
Force x distance.
According to my physics the length of rod he is using meets the necessity of rated bolt torque of nissan.
But they are never left loosened, never.

You can do the lever arm length and fruit ka thelay ki "wazan ki baat" torque tightening or even find a spring scales and cobble up a lever arm to calculate applied torque OR buy a torque limit ratchet (torque wrench) - if a mechanic has not bought one yet and he is working on engines and similar assemblies since 20 years or so - In my books that is not being honest with your work.

Next you will be telling me he's using bathroom grade RTV silicone on the timing case and sump.

for head-bolts look at the post above.

[Xulfiqar]

And @sergtr maybe I'm confusing to things up
Bore is still the same as it was.
Only head facing is done.
I thought honing is also consider as shaving of the surface of metal using machinery so i thought you're asking in that way.
As we know bore size is 80mm
When we dropped its current rings in to cylinder, they were too loose were slipping inside as if there's no friction.

So when we dropped 90mm rings of Toyota 4AF
They were like 3mm more in diameter. They were very nicely trimmed and were brought to approximately 87mm. So currently my bore size is on 87mm. And piston rings were too of some Toyota I'll state u it's name too soon. But that piston pin is very heavy duty as compared to its genuine ring.

This could've been played better if i could get QG18de genuine pistons. It would have genuine diameter of pin so QG18de piston would fit in easily but since piston pin cavity currently was widened Slightly so con rod was having pley in it. Creating noises. So I've basically restored my piston to work as new piston with good compression.

And those were black bolts don't seem tty bolts. They were as good as new. No expansion at all in them.

which toyota 4AF has 90mm bore? - all of them are 81mm - your nissan is 80mm.

how does a 90mm ring filed to 87mm fit an 80mm bore?

[FBB]

Aap sab mil k bache ki jan lo ge kya??? Choro bhi yar jane do us ki gari hai us ka engine hai jo dil kare karta rahe [emoji12]

Sent from my Z12 using Tapatalk

[YamahaYB100]

the reason the bolts are replaced is because they actually elongate when under tension - this keeps the head in place very tightly and every evenly and actually omits the "second tightening" of the cylinder heads which used to be a norm in engines from the 1960s

With TTY bolts - when they are brand new their thread pitch is even all the way and they have a set length, When they are installed and torqued up - they deform and the thread pitch changes where the threads are exposed - This is because the bolt has now stretched and is useless. If you try to reuse them there is a 50% chance of failure as the head is not bolted tight enough to the block and may warp when the engine warms up. I consider that very bad practice because a new set of headbolts are cheap compared to tearing down the engine again.

Some manufacturers do provide a spec length and service limit for the headbolts but till date I have only seen one or two actually falling into acceptable wear limit - almost everytime TTY bolts were scrap when removed.

newer engines even use TTY bolts on the con-rods - and when they let loose, kiss your engine block goodbye because the rod will shoot out of its side.

claiming that "engine is running" that is what matters is extremely shoddy. Specially when you know that the correct technique and replacement was not followed.

You are right and my mechanic always use new bolts for my td27 engine and if I'm not wrong he also used on mazda R2 too..does R2 also have TTY bolts..

[ahmed2396]

Toyossan
good 4AFE rings on QG18DE? i don't think so.

[YamahaYB100]

You can do the lever arm length and fruit ka thelay ki "wazan ki baat" torque tightening or even find a spring scales and cobble up a lever arm to calculate applied torque OR buy a torque limit ratchet (torque wrench) - if a mechanic has not bought one yet and he is working on engines and similar assemblies since 20 years or so - In my books that is not being honest with your work.

Next you will be telling me he's using bathroom grade RTV silicone on the timing case and sump.

for head-bolts look at the post above.

I don't wanna hijack this thread..but @xulfiqar...what about Mega Grey silicone for oil sump and lion shellac gasket (for head gasket)...i allways used that

[syncview]

And I've built QG 15 and one QG16 and I've never replaced head bolts. Look we don't have accuracy here according to nissan bolt torque. Torque is nm means newtonxmeters
Force x distance.
According to my physics the length of rod he is using meets the necessity of rated bolt torque of nissan.
But they are never left loosened, never.

its not only a matter of bolts left loose
tightening torque and its evenness throughout is VERY critical

otherwise we get to hear concepts such as 1KZ ke head mei masla hai, Honda ke engine rebuild nahi hotay, Honda ka head sahee nahi lagta

[Xulfiqar]

You are right and my mechanic always use new bolts for my td27 engine and if I'm not wrong he also used on mazda R2 too..does R2 also have TTY bolts..

yes mazda R2 head bolts are TTY - mazda write them as "TTYL" torque to yield loss

[dani_kk]

Hahahahahaha you guys should start designing engine for nissan cars.
No more comments from my end. I appreciate your suggestions and advices, thank you dears.
@qamarahmadawan bhai yeh I'm being annoyed.
Commenting on pakwheels is very easy, bringing these machines in action is pretty difficult thing. I know what i am doing. My projects are always successful. This post was just to tell everyone that this engine can be built.

[dani_kk]

It's a open challenge to you all nissan car maestro's. Invoke your knowledge build a engine with your nissan manual knowledge and then compare it with what I've built.. Thanks.

[dani_kk]

I don't just comment, i apply and show what i know about nissan's.. You guys would be senior, your suggestions would be authentic, I'm not denying anything. But i take advices and do what i like to do, i don't just go and work on someone's advices.