[anupmathur]

Originally Posted by aaggoswami

So there was pressure inside. As soon as the sump broke down, the oil that was under pressure suddenly found a way to go out.

The oil in the sump is not under pressure. The sump is, in fact, a vented 'container' only.

Originally Posted by ThE_DoN

The instant it broke the strainer the oil to the cam stopped and it caused an instanttaneous increase in heat and expansion of the cam rod. The rest you can see in the pics.

Impossible. That's not how it happens. There is no such instantaneous heating!
Further, there are no signs of anything having overheated. Steel will show a blue tint or a rainbow tint if heated excessively!

[aaggoswami]

Originally Posted by anupmathur

The oil in the sump is not under pressure. The sump is, in fact, a vented 'container' only.

I meant that the oil inside engine was in pressure as the engine was already running at optimum temperature.

In books I read about heat and pressure, but practically learn the hard way round for both engine oil and coolant. Hence my term was that it was pressure that lead to sudden loss of oil that we can also see in engine bay.

[headers]

Originally Posted by anupmathur

Impossible. That's not how it happens. There is no such instantaneous heating!
Further, there are no signs of anything having overheated. Steel will show a blue tint or a rainbow tint if heated excessively!

A +10 to that

Originally Posted by aaggoswami

I meant that the oil inside engine was in pressure as the engine was already running at optimum temperature.

In books I read about heat and pressure, but practically learn the hard way round for both engine oil and coolant. Hence my term was that it was pressure that lead to sudden loss of oil that we can also see in engine bay.

Sir, oil sumps cracking is not a new phenomenon and engine designers defintely take into account the ability of a cam to run without oil for a few minutes.

Also, as mentioned before, camshafts are ultra high precision components and do not fracture like that unless they had a manufacturing defect that was not sighted previously

Also, the engine was supposedly running fine until switch off! There is something fishy here!

[ported_head]

What do these gears drive?



It's a little difficult to believe this sudden expansion theory. The lubrication film thickness will be really small, say 20-30 thousandths of an inch. Of course, these vary depending on camshaft design, loads, etc. But it's a really thin film. And it would be really difficult to do away with the film completely, even if the oil was suction drained. And to then douse with generous quantities of kerosene.

The camshaft bearing clearance in my petrol Swift engine runs to an upper limit of about 30 thousandths of an inch. For the camshaft to expand that much, depending on whatever the coefficient of thermal expansion of the material used, would mean a really sharp rise in temperature in a really short time. Since you said, you didn't drive around or idled for too long after the incident. And this would be if the camshaft was unable to dissipate any heat, ie completely devoid of oil, and head of coolant etc.

Did they check the bearing clearances for the camshaft? Did you see any wear or scuff marks inside the bearing surface. It would be a good idea to see that the head is opened only in your presence to inspect rest of the damage.

[ThE_DoN]

Originally Posted by ported_head

Attachment 145209

What do these gears drive?



It's a little difficult to believe this sudden expansion theory. The lubrication film thickness will be really small, say 20-30 thousandths of an inch. Of course, these vary depending on camshaft design, loads, etc. But it's a really thin film. And it would be really difficult to do away with the film completely, even if the oil was suction drained. And to then douse with generous quantities of kerosene.

The camshaft bearing clearance in my petrol Swift engine runs to an upper limit of about 30 thousandths of an inch. For the camshaft to expand that much, depending on whatever the coefficient of thermal expansion of the material used, would mean a really sharp rise in temperature in a really short time. Since you said, you didn't drive around or idled for too long after the incident. And this would be if the camshaft was unable to dissipate any heat, ie completely devoid of oil, and head of coolant etc.

Did they check the bearing clearances for the camshaft? Did you see any wear or scuff marks inside the bearing surface. It would be a good idea to see that the head is opened only in your presence to inspect rest of the damage.

From what i could understand of the functioning of the cam - The smaller broken part is connected to the timing chain and drives the cam rod (broken one), the two gears that you highlighted may be only used to twist the second cam rod (non-broken).

I have already intimidated to Spectra that I want to be there in person when they open the head. Also, one thing they told me that the bolts used to screw the head are single use and unique bolts. i.e They have to be broken to be opened and cant be re-used (red arrow). Also, all 10 bots themselves are unique and can;t be interchanged. This kind off gave me a secured feeling that the head may not have been opened or tampered with.

[headers]

Originally Posted by ThE_DoN

From what i could understand of the functioning of the cam - The smaller broken part is connected to the timing chain and drives the cam rod (broken one), the two gears that you highlighted may be only used to twist the second cam rod (non-broken).

I have already intimidated to Spectra that I want to be there in person when they open the head. Also, one thing they told me that the bolts used to screw the head are single use and unique bolts. i.e They have to be broken to be opened and cant be re-used (red arrow). Also, all 10 bots themselves are unique and can;t be interchanged. This kind off gave me a secured feeling that the head may not have been opened or tampered with.

Sir, its the other way around. The timing gear is on the left side in the picture. As it is a DOHC engine, both cams rotate simultaneously.

Also, ask them to rotate the engine by hand to check if the movement is free. If it rotates freely, one need not open the engine at all! if the crank is rotated, the engine will / should rotate.

3rdly, the bolts can be re-used if opened correctly.

[anupmathur]

Originally Posted by ThE_DoN

From what i could understand of the functioning of the cam - The smaller broken part is connected to the timing chain and drives the cam rod (broken one), the two gears that you highlighted may be only used to twist the second cam rod (non-broken).

Originally Posted by headers

Sir, its the other way around. The timing gear is on the left side in the picture. As it is a DOHC engine, both cams rotate simultaneously.

Indeed, those are the timing 'gears' and both are rotated simultaneously by the chain driven by the 'gearwheel' mounted on the crankshaft.

It is unusual to have bolts that are single use only. Is that how these are?
Normally, if the correct procedure is followed for opening, the bolts would stay re-usable. There could, however, be a service life specified in hours or kms of use.

[rjvora_2000]

Originally Posted by ThE_DoN

Hi All,

I had a visit to Spectra today along with 'rjvora_2000' (Thw man has a gem of a heart - Sincere thanks for accompanying me today sir)

Awaiting Royal Sundarams official reply on Tuesday! A hearty thanks to rjvora once again !!

Thank you for your kind words. That's reason why I am hear on TEAM-BHP to help member's and make new friends like you.

My fingers are crossed and I am hoping that your claim will be payable full.

[pedrolourenco]

Originally Posted by ThE_DoN

Swift Dzire Vdi accident leads to major engine damage - Royal Sundaram/Maruti Insurance refuses claim

Hi Guys,

I have been facing a huge problem since the last few weeks. What started as a minor accident with me going over an ill fated stone has turned out to haunt me as full blown engine damage. The worst part of the above statement is I did nothing wrong, in fact I did what I have learned over the years being a part of this forum. Our family has a history of driving cars for more than 15 years and it is well-known understanding to stop the car and the engine immediately in case of a front end accident. My car is around 4 months old and is insured by Royal Sundaram/Maruti insurance. Let me run you all through the incidents.

P.S. The pictures show the place of the accident and towing, the damage to the oil sump, amount of leaked oil, damage to the engine camshaft. The eighth picture shows the kinf of stone that went under the car.

A little OT but photos 2, 3 & 4 show a sticker with FGP. Now we've heard of SGP & MGP. What is FGP? Fiat Genuine Part?

[ThE_DoN]

Originally Posted by anupmathur

Indeed, those are the timing 'gears' and both are rotated simultaneously by the chain driven by the 'gearwheel' mounted on the crankshaft.

It is unusual to have bolts that are single use only. Is that how these are?
Normally, if the correct procedure is followed for opening, the bolts would stay re-usable. There could, however, be a service life specified in hours or kms of use.

Guys I have a query as to what exactly do you think must have happened in the engine.
What I was explained by the works manager is that the timing chain continued to move the cam, while the cam had expanded and hence leading to a broken cam rod. BUT, while showing the cam he said that this part(yellow arrow) has expanded and when this part(red arrow) tried to move it craked th cam.

NOW, if the timing chain is on the other side liek you guys mentioned, shouldn't the crack be in this section (red rectangle) instead ??

What i can see from a different pic is, I beleive the JAM happened at the other end (red arrow) instead of what the works manager thinks (red arrow).

In this scenario, MY BIGGEST QUESTION is does this mean that the damage to valves and pistons are restricted only one piston - Since the cam was moving correctly in the rest of the broken section and the above rod as well. We can also see that the tappets of the broken section have broken (third pic - Red circle).

Is a logical conclusion that since the cam in this piston did not open/close the valves properly this valve-piston set must have definately been damaged - specifically the above section - (Yellow rectangle). However, the other 3 piston and valve sets must be in perfect condition.

I need advice from you all on this since this would help me avoid the BS that Spectra is giving me regarding replacing all the valves and pistons and reboring etc !!!

[ported_head]

Originally Posted by headers

Sir, its the other way around. The timing gear is on the left side in the picture. As it is a DOHC engine, both cams rotate simultaneously.

Originally Posted by anupmathur

Indeed, those are the timing 'gears' and both are rotated simultaneously by the chain driven by the 'gearwheel' mounted on the crankshaft.

Doesn't this look more like the chain driven camshaft gear? The gears I queried about don't seem to look like something that is chain driven. Instead, they seem to be meshing with each other.

Though, now that it's broken from the end of the camshaft at the driven side, it definitely adds a new dimension to the problem.

[Spitfire]

In the pic above its the chain driven end of the camshaft. The other 2 gears drive the other camshaft.

The pictures are horrible, a nightmare.

About the sudden increase in heat, thats a load of BS. Look a the place it has broken, its a shear mark.

Tha only way(i think) this could have happened is the non broken cam could have jammed, in turn making the chain driven cam jam too.

Now the chain driven gear could have put tremendous twisting torque on the cam and this could have sheared it into two.

No experience working with CRDE engines. But i have seen an open engine of the Swift VDi.

[anupmathur]

Originally Posted by Spitfire

In the pic above its the chain driven end of the camshaft. The other 2 gears drive the other camshaft.

You are right, Spitfire.
But I am amazed that the camshaft sheared and there is no damage to the driving pulley and it's teeth! Isn't this very telling?

Actually it is rather futile to do a forensic analysis sitting miles away, not having even set eyes on the damage!
Are any tappets/rockers damaged?
What about piston and connecting rod? How many? etc...

[headers]

Originally Posted by Spitfire

No experience working with CRDE engines. But i have seen an open engine of the Swift VDi.

Sir, the engine in question is a Swift Desire LDi which is the same as the swift VDi.

[Spitfire]

Originally Posted by headers

Sir, the engine in question is a Swift Desire LDi which is the same as the swift VDi.

Saar?? What Saar??

Ok so i used Mahindra's term for the Maruti Engine. I didnt get the point of your post.
Where in the above did i say VDi is different from LDi. I saw an open engine from a VDi.