Metal Piece in Piston Crown

[Ted]

Dear Fellows,

 

Could you please give me an idea to my problem? There was an external metal piece of size around 5mmx3mmx2mm on top of 4th piston of my engine (5A-FE). Luckily it had only carved small areas (5mmx3mmx2mm) on piston crown and also head surface. I removed it. I was unable to remove the piston and check. But from top there were no cracks in the piston. With this metal piece engine ran around 20kms. Now after I removed I feel the engine is vibrating in high rpms than before. Also there is a very small sound coming from the engine. Could you please advice me to what can happen to the engine due to this metal piece? Has my crank shaft bent? Has my 4th piston connecting rod bent? I highly appreciate your kind reply.

[gayanath]

How it goes inside?

How you removed it?

[tiv]

  On 4/6/2020 at 4:02 PM, Ted said:

Dear Fellows,

 

Could you please give me an idea to my problem? There was an external metal piece of size around 5mmx3mmx2mm on top of 4th piston of my engine (5A-FE). Luckily it had only carved small areas (5mmx3mmx2mm) on piston crown and also head surface. I removed it. I was unable to remove the piston and check. But from top there were no cracks in the piston. With this metal piece engine ran around 20kms. Now after I removed I feel the engine is vibrating in high rpms than before. Also there is a very small sound coming from the engine. Could you please advice me to what can happen to the engine due to this metal piece? Has my crank shaft bent? Has my 4th piston connecting rod bent? I highly appreciate your kind reply.

 

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If you went through all the trouble to open the engine, inspect the piston for cracks it was not that smart to close the whole thing up without giving it a once over, atleast for peace of mind

There maybe cracks not visible and given the pressures it encountered may have problems on the bearings as well. 

If I were you I would have replaced the piston anyhow, with atleast a used one. 

There maybe nothing at all, or hell inside but now u dont have the peace of mind and cant be sure if the car is reliable. 

Back in the day my grandfather had a land rover s3, after about approx 200,000km, we opened the diesel engine as it was a bit low on power. To our surprise the the head had a microscopic crack was seeping water onto the piston, and the thing had been happening so long the piston was eroded right through with like a 1mm shim off it causing blow by. 

We actually repaired the head and replaced with a used piston, the thing is running to date.

 

[Ted]

  On 4/7/2020 at 9:58 AM, tiv said:

If you went through all the trouble to open the engine, inspect the piston for cracks it was not that smart to close the whole thing up without giving it a once over, atleast for peace of mind

There maybe cracks not visible and given the pressures it encountered may have problems on the bearings as well. 

If I were you I would have replaced the piston anyhow, with atleast a used one. 

There maybe nothing at all, or hell inside but now u dont have the peace of mind and cant be sure if the car is reliable. 

Back in the day my grandfather had a land rover s3, after about approx 200,000km, we opened the diesel engine as it was a bit low on power. To our surprise the the head had a microscopic crack was seeping water onto the piston, and the thing had been happening so long the piston was eroded right through with like a 1mm shim off it causing blow by. 

We actually repaired the head and replaced with a used piston, the thing is running to date.

 

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Yes. I am going to replace the piston with a used one, Since u know what? I have another good engine destroyed... this is my story, summerising,

1) wanted to replace engine rather overhauling and bought a very nice eninge..

2) maka bass destroyed my engine - timing belt left less tension and skipped.. I saw from manifold hole, 4th cylinder valve stem had broken into pieces.

3) bought another engine (only head and block), I did timing belt my self asked maka bass only to  swap.

4) unfortunately a small metal part of that broken valve stem had gone inside intake manifold and had come into the second new engine.

So this is my story.. having spent for two engines.. still struggling to finalise..

anyway.. I will replace this fourth piston with a used one from my first new engine.. we will see.. thanks a lot for your comment....

[Ted]

  On 4/7/2020 at 4:19 PM, Ted said:

Yes. I am going to replace the piston with a used one, Since u know what? I have another good engine destroyed... this is my story, summerising,

1) wanted to replace engine rather overhauling and bought a very nice eninge..

2) maka bass destroyed my engine - timing belt left less tension and skipped.. I saw from manifold hole, 4th cylinder valve stem had broken into pieces.

3) bought another engine (only head and block), I did timing belt my self asked maka bass only to  swap.

4) unfortunately a small metal part of that broken valve stem had gone inside intake manifold and had come into the second new engine.

So this is my story.. having spent for two engines.. still struggling to finalise..

anyway.. I will replace this fourth piston with a used one from my first new engine.. we will see.. thanks a lot for your comment....

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BDW, What you think? has my crank shaft bent? or that pressure absorbed by piston or piston rod?

[varotone]

After damaging the valves from wrong timing, you replaced only the block and head. Along with the head did you replace only the broken valve or all valves, rocker arm shafts and the cam shaft?

It's very likely that more than one valve was damaged from wrong timing. Valves will be the first to damage, but crank shaft and con rods also may be damaged. So check all the connecting rods, gudgeon pins, crank shaft and pistons while you are at it. You'll have to take the crank shaft to a machine shop to check it. It's worth the pain because if it's bent it will cause serious damage to the bore.

Because the metal piece was floating around inside the ignition chamber, it may have damaged valve seats as well. Check that as well.

BTW, why did you swap the engine when you could have rebuilt it?

[Ted]

  On 4/7/2020 at 6:17 PM, varotone said:

After damaging the valves from wrong timing, you replaced only the block and head. Along with the head did you replace only the broken valve or all valves, rocker arm shafts and the cam shaft?

It's very likely that more than one valve was damaged from wrong timing. Valves will be the first to damage, but crank shaft and con rods also may be damaged. So check all the connecting rods, gudgeon pins, crank shaft and pistons while you are at it. You'll have to take the crank shaft to a machine shop to check it. It's worth the pain because if it's bent it will cause serious damage to the bore.

Because the metal piece was floating around inside the ignition chamber, it may have damaged valve seats as well. Check that as well.

BTW, why did you swap the engine when you could have rebuilt it?

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I replaced with another new engine with new head, new block, new valves, new everything...

 

[Devinda_Z]

@Ted too late now but do you  perhaps feel it may have been better/cheaper/easier if you had got a reputed technician to rebuild your engine?

Also be mindful of the fact that your insurance policy will have one engine number and another in your car, which also will not correspond with your certificate of registration so you may be giving them a reason to deny a claim since you've made a serious change to the vehicle outside of the legal due process

[Ted]

  On 4/9/2020 at 5:27 PM, Devinda_Z said:

@Ted too late now but do you  perhaps feel it may have been better/cheaper/easier if you had got a reputed technician to rebuild your engine?

Also be mindful of the fact that your insurance policy will have one engine number and another in your car, which also will not correspond with your certificate of registration so you may be giving them a reason to deny a claim since you've made a serious change to the vehicle outside of the legal due process

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My friend if they are my problems, I would have published already ryt? So if you cannot respond with relevant facts keep calm and stay home...