M20 Engine Overhaul

[june_yap]

Anyone have any experience overhaul this M20 engine? May I know how long does it takes and what is the damage? Thanks...

 

[Vincent Hor]

Why do you need to overhaul your engine?

 

[Jules]

not powderful enough-lar.....LOL!

 

[ALBundy]

Anyone have any experience overhaul this M20 engine? May I know how long does it takes and what is the damage? Thanks...

June, is it a complete overhaul or just a top overhaul??

Top overhaul mainly involves work on the cylinder head, regrinding the valves, change the valve seals (oil burning when engine is cold) and replace the head gasket.

A complete overhaul will include replacing piston rings, engine and conrod bearings, oil sump gasket and etc.

Time duration usually depends on your mechanic's efficiency, its should not take more than a week.

Cheers

 

[june_yap]

The reason to do overhaul is because the exhaust starts to keluar abit asap (blue white) ( eating black oil ) , i think this is only involve top overhaul right? correct me if wrong, anyone did this before? anyway, power still good! just concern.

 

[SS626A]

I think u need to check all of your valve &^ head gasket condition first. If the engine top condition is ok. U hv go to check all you piston ring and piston crown.

 

[june_yap]

I think u need to check all of your valve &^ head gasket condition first. If the engine top condition is ok. U hv go to check all you piston ring and piston crown.

u mean this can be d.i.y??

 

[SS626A]

Depends to your skill & tools u hv nw. But I think better let's your mechanic to do tat. I worry tat your piston crown crack. Its cost your alot of $.

 

[june_yap]

wow! piston crown crack?? lots of money?? hmmm... scared me la... hope its not crack... so how???

 

[SS626A]

Dont worry. Mayb just a small problem but not a piston crown problem. I think ur mechanic can check tis 4 u. BTW, u can check ur lud oil consumption & notice d lub oil mix wif water or not.

 

[teejay]

The reason to do overhaul is because the exhaust starts to keluar abit asap (blue white) ( eating black oil ) , i think this is only involve top overhaul right? correct me if wrong, anyone did this before? anyway, power still good! just concern.

Hi June,

There are various ways to diagnose leaking engine oil into the combustion chamber. A few things you should note and inform your mechanic when you bring it in for exact troubleshooting
1. the smoke comes out when the engine is hot or cold?
2. did you recently change to a thinner engine oil?
3. any recent abuse on the engine, i.e. high revs a very spirited driving?
4. any additives added to the engine lately?
5. did you leave the car to service/repair to someone not familair with your car? i.e. japanese mech or those quick service workshops?

For the engine oil to get into the combustion chamber a few factors listed that are common the m20 engines
1. valve guide worn
2. thinner, much thinner engine oil used from a sudden thick engine oil.
3. cracked cylinder head - this would also cause a high temp reading, i.e. engine temp at 3/4 if you stay idle for long.
4. worn pistons rings - very common due to not servicing the engine at regular intervals
5. overfill of engine oil - the excess oil can make its way into the vaccum ducts and spark plug chamber
6. worn camshaft - hardly happens unless cam has been regrinded before.
7. no such thing as cracked piston crown as the engine would sounds as if its running on 5 cylinders due to loss in compression in 1 chamber., cracked piston crown onl happens to Forced Induction engines - turbos,supers,hemis etc


you can ask your mech to do a compression test on each cylinder to rule out the piston rings, if your compression is good, then very highly chance its the valve guides, which entails top overhaul, cost ranges from 1k-4k, depending on the parts that are changed

 

[SS626A]

Good explanation teejay!! M20 sifu here! U experience all of tis b4 teejay?

 

[XXX]

if ur going to do a complete overhaul u might as well send for port and polish and balance the engine...more importantly balancing the engine..I did mine few years back RM1700 now I dunno how much since the price of rice went up...and all mechanic eat rice....:burnout:

 

[fabianyee]

if ur going to do a complete overhaul u might as well send for port and polish and balance the engine...more importantly balancing the engine..I did mine few years back RM1700 now I dunno how much since the price of rice went up...and all mechanic eat rice....:burnout:

does that include ball balancing???

 

[XXX]

...balls balancing ...for you free....I will ask my dog to nibble until its balanced...no guarantee though if end up without ballss...

 

[june_yap]

great explaination from all sifu2.... huh...

 

[teejay]

Good explanation teejay!! M20 sifu here! U experience all of tis b4 teejay?

yes i have, been there, done that, etc,etc.... 8 years of playing with the m20 has earn me the cult status quo....:stupid:

 

[SS626A]

yes i have, been there, done that, etc,etc.... 8 years of playing with the m20 has earn me the cult status quo....:stupid:

Wah......:top:

 

[Zoggee]

Look at Teejay's and Bundy's reply...then go ask your mechanic. Ask them to quoted you from there on.

 

[ALBundy]

The reason to do overhaul is because the exhaust starts to keluar abit asap (blue white) ( eating black oil ) , i think this is only involve top overhaul right? correct me if wrong, anyone did this before? anyway, power still good! just concern.

Does it happen only when the engine is cold or ALL the time?

If it is happening all the time, chances are the piston rings need to be replaced, and you should then do a complete overhaul.

Cheers