engine overhaul

May 4, 2016
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Hello to all,

would like to ask what do they change/repair/add etc when you overhaul your engine.
Just took my bro's car using evo 3 engine.Leaking here & there , sometimes got white smoke ,
always overheat plus few more problem la senang cakap.Went to few workshop they said better overhaul.so now having only 20% knowledge in turbo engine seeking sifu's advise on engine overhaul.
Thanks in advance:adore:
 

Izso

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Assuming top overhaul - valve seats, valve regrind, skim head, change all oil seals and gaskets, if extra hard working the head studs are changed to new ones too, turbo is serviced, and erm... I think that's it. If full overhaul then you'd have the piston rings changed, all the bearings/oil seals for the block and sometimes people take out the crank for polishing and rebalancing, some folks rebore and fit in new cylinder liners, change oil pump, water pump and timing belt/chain.

I'm sure I missed a few things but these are the main ones.
 

RENESIS VIII

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RENESIS VIII

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Assuming top overhaul - valve seats, valve regrind, skim head, change all oil seals and gaskets, if extra hard working the head studs are changed to new ones too, turbo is serviced, and erm... I think that's it. If full overhaul then you'd have the piston rings changed, all the bearings/oil seals for the block and sometimes people take out the crank for polishing and rebalancing, some folks rebore and fit in new cylinder liners, change oil pump, water pump and timing belt/chain.

I'm sure I missed a few things but these are the main ones.
If I want to do all that(minus the turbo part) on a 4G15, how much will it roughly cost? My engine has clocked 200k km and has never been overhauled before. Will there be any noticeable performance gain after overhaul?
 

vr2turbo

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If I want to do all that(minus the turbo part) on a 4G15, how much will it roughly cost? My engine has clocked 200k km and has never been overhauled before. Will there be any noticeable performance gain after overhaul?
Even though have clocked 200k km anything wrong with your engine? Dies it Consume engine oil, does it have white smoke coming out while driving? If not, just use loh!:biggrin:
 

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Even though have clocked 200k km anything wrong with your engine? Dies it Consume engine oil, does it have white smoke coming out while driving? If not, just use loh!:biggrin:
Doesn't seem to consume engine oil. No white smoke either despite revving to 5000rpm. Just got some weird petrol smell.
 

lsm1991

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lsm1991

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Doesn't seem to consume engine oil. No white smoke either despite revving to 5000rpm. Just got some weird petrol smell.
if it seems alright, no real need to overhaul... petrol smell is probably something else.... if its exhaust smell, maybe air masuk from the boot seal behind
 

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Doesn't seem to consume engine oil. No white smoke either despite revving to 5000rpm. Just got some weird petrol smell.
That is not engine problem, so no need waste money overhaul at the moment Try to check where the petrol smell coming from.....
 

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if it seems alright, no real need to overhaul... petrol smell is probably something else.... if its exhaust smell, maybe air masuk from the boot seal behind
That is not engine problem, so no need waste money overhaul at the moment Try to check where the petrol smell coming from.....
From the exhaust. I'm not sure is it really petrol smell but that is what my family calls it. But it does smell different from the smell at petrol station. Some other cars in my house have that kind of smell too just that the smell from my car is stronger especially during startup after a long time. If the engine has been running for a while, then the smell is not that strong, barely noticeable.
 

lsm1991

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From the exhaust. I'm not sure is it really petrol smell but that is what my family calls it. But it does smell different from the smell at petrol station. Some other cars in my house have that kind of smell too just that the smell from my car is stronger especially during startup after a long time. If the engine has been running for a while, then the smell is not that strong, barely noticeable.
i know for old gen saga's.... my old saga smelt abit of exhaust at the back... then when the car is turned off there is usually a strange wave of petrol smell.... found out it was exhaust leaking into the car via the back hatch

the other potential issue is.. you might have a leak somewhere along the pipe
 

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i know for old gen saga's.... my old saga smelt abit of exhaust at the back... then when the car is turned off there is usually a strange wave of petrol smell.... found out it was exhaust leaking into the car via the back hatch

the other potential issue is.. you might have a leak somewhere along the pipe
Could be a leak somewhere or the catalylic converter is no longer filtering as much as it is before due to old age. But is weird that after a drive, the smell is no longer there. Is it only there when I start the car or when I keep revving the engine.
 

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Could be a leak somewhere or the catalylic converter is no longer filtering as much as it is before due to old age. But is weird that after a drive, the smell is no longer there. Is it only there when I start the car or when I keep revving the engine.
Initial start probably rich air fuel mixture, probably cold start choke on and un-burnt fuel coming out, that is why after warm up no more smell.

Your Wira got Catcon?:rolleyes:
 

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Initial start probably rich air fuel mixture, probably cold start choke on and un-burnt fuel coming out, that is why after warm up no more smell.

Your Wira got Catcon?:rolleyes:
Choke? I thought choke is only available in carburetors. Maybe it is un-burnt fuel. The smell is quite hard to bear. Feels like want to vomit if I inhale it too much.

The round middle thing on the middle of exhaust piping is not cat con? Or that is a different thing?
 

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Choke? I thought choke is only available in carburetors. Maybe it is un-burnt fuel. The smell is quite hard to bear. Feels like want to vomit if I inhale it too much.

The round middle thing on the middle of exhaust piping is not cat con? Or that is a different thing?
Not mechanically, but electronically. When the system senses the engine is cold the ECU keeps the air fuel mixture rich for it to idle until it warm up then goes back to normal. So when the mixture is rich probably have some un burnt fuel left over and that could be the petrol you smelt.

If at the center of the exhaust system likely is your mid or bullet, Cat normally up front nearer the engine
 

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If I want to do all that(minus the turbo part) on a 4G15, how much will it roughly cost? My engine has clocked 200k km and has never been overhauled before. Will there be any noticeable performance gain after overhaul?
Depending on where you do it - wira ranges between 3.5k to 5k thereabouts. And once you skim the head you'll definitely feel a difference.

And like what Vr2turbo said - if there's nothing wrong with the engine such as burning off oil, leaks, loud clacking noises, severe loss of power, etc.. why would you want to overhaul? Just a note though, at that kind of mileage I hope you've already changed your timing belt at least twice.

Choke? I thought choke is only available in carburetors. Maybe it is un-burnt fuel. The smell is quite hard to bear. Feels like want to vomit if I inhale it too much.

The round middle thing on the middle of exhaust piping is not cat con? Or that is a different thing?
The fuel smell has a few possibilities. Your car is running super rich for some reason. When was the last time you cleaned your TB and changed your fuel filter and charcoal canister? Have you checked your spark plugs? Are your coils running right? Are the plug cables any good?

The exhaust generally looks like this :

Extractor --> catcon --> Flexijoint / pineapple --> resonator --> muffler

But looking at the age of your car even if you had a catcon, it's probably completely worn out anyway.

Check to see if the exhaust fumes when starting the car (cold) has strong petrol fumes. If yes then your car has a problem somewhere causing it to run rich. If not, then it's possible you have a failed seal somewhere. I can't recall if the Wira had a petrol filter seal or whatever you call it, the Myvi has this issue with that seal that once broken, the petrol fumes will seep into the cabin. But for the Myvi the smell is always there, not just cold start.

Oh and what type of spark plugs you using? Too cold range perhaps?
 

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Not mechanically, but electronically. When the system senses the engine is cold the ECU keeps the air fuel mixture rich for it to idle until it warm up then goes back to normal. So when the mixture is rich probably have some un burnt fuel left over and that could be the petrol you smelt.

If at the center of the exhaust system likely is your mid or bullet, Cat normally up front nearer the engine
I see. Probably is unburnt fuel then. The Myvi in my house have that kind of smell too during cold start, just not that strong.

Depending on where you do it - wira ranges between 3.5k to 5k thereabouts. And once you skim the head you'll definitely feel a difference.

And like what Vr2turbo said - if there's nothing wrong with the engine such as burning off oil, leaks, loud clacking noises, severe loss of power, etc.. why would you want to overhaul? Just a note though, at that kind of mileage I hope you've already changed your timing belt at least twice.



The fuel smell has a few possibilities. Your car is running super rich for some reason. When was the last time you cleaned your TB and changed your fuel filter and charcoal canister? Have you checked your spark plugs? Are your coils running right? Are the plug cables any good?

The exhaust generally looks like this :

Extractor --> catcon --> Flexijoint / pineapple --> resonator --> muffler

But looking at the age of your car even if you had a catcon, it's probably completely worn out anyway.

Check to see if the exhaust fumes when starting the car (cold) has strong petrol fumes. If yes then your car has a problem somewhere causing it to run rich. If not, then it's possible you have a failed seal somewhere. I can't recall if the Wira had a petrol filter seal or whatever you call it, the Myvi has this issue with that seal that once broken, the petrol fumes will seep into the cabin. But for the Myvi the smell is always there, not just cold start.

Oh and what type of spark plugs you using? Too cold range perhaps?
Changed the timing belt for the 3rd time at 206k km mileage in January 2016. Previous one is done at 160k km.

Perhaps my car is really running rich. Somehow the mileage I get in city drive seems to be quite bad as I have heard AT 4G15 Wira getting better mileage than mine. Need to ask the mechanic next time to do a checkup.

Inside the cabin, there is no smell at all. Just the smell is noticeable at the back of the car coming out from the exhaust. Smell is also not present in front even when I pop up the hood during startup.
I'm using NGK spark plugs. Ordinary ones.
 

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y2188

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I see. Probably is unburnt fuel then. The Myvi in my house have that kind of smell too during cold start, just not that strong.



Changed the timing belt for the 3rd time at 206k km mileage in January 2016. Previous one is done at 160k km.

Perhaps my car is really running rich. Somehow the mileage I get in city drive seems to be quite bad as I have heard AT 4G15 Wira getting better mileage than mine. Need to ask the mechanic next time to do a checkup.

Inside the cabin, there is no smell at all. Just the smell is noticeable at the back of the car coming out from the exhaust. Smell is also not present in front even when I pop up the hood during startup.
I'm using NGK spark plugs. Ordinary ones.
Should be running very rich..i think
 

lsm1991

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lsm1991

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some cars, especially those performance cars memang run super rich...

better rich than lean i always say~
 

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