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TR2/3/3A TR3 Piston Sleeves

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Detonation could have many causes. The gist is that instead of the single ignition of the cylinder mixture by the spark plug, followed by a smooth burning across the chamber, there is a second ignition point. With 2 flame fronts, when they reach each other, the remainder of the mixture explodes simultaneously. It is equivalent to hitting the piston and chamber with a hammer.

Causes of the second flame front can be:

1) Ignition timing advanced too much, so the cylinder pressure becomes too high.
2) Poor fuel octane
3) Hot carbon in the cylinder
4) to high compression for the fuel octane
5) to hot of a plug rating
6) sharp metal edges heating in the cylinder
7) Cam timing

Normally the cast aluminum piston is the weakest part of the combustion chamber, and the ring lands are the weakest part of the piston...so they tend to go first. On more high performance pistons, with thinner crowns, the crown is the weakest point.
 
CJD said:
Detonation could have many causes. The gist is that instead of the single ignition of the cylinder mixture by the spark plug, followed by a smooth burning across the chamber, there is a second ignition point. With 2 flame fronts, when they reach each other, the remainder of the mixture explodes simultaneously. It is equivalent to hitting the piston and chamber with a hammer.

Causes of the second flame front can be:

1) Ignition timing advanced too much, so the cylinder pressure becomes too high.
2) Poor fuel octane
3) Hot carbon in the cylinder
4) to high compression for the fuel octane
5) to hot of a plug rating
6) sharp metal edges heating in the cylinder
7) Cam timing

Normally the cast aluminum piston is the weakest part of the combustion chamber, and the ring lands are the weakest part of the piston...so they tend to go first. On more high performance pistons, with thinner crowns, the crown is the weakest point.
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Excellent write up and all valid points; more in depth than my quick one. The 36 cause is interesting and one I was not thinking of. Thats may apply to my case. Thanks for the great write up.
 
Thanks John for the good write up. I think the double spark stuff is what I heard about with the split fire plugs probably because of the 2 prongs on the plug. Many years ago I had this poor running tr3 with oil going by the oil rings. I tried some of the split fire plugs and it made a difference.

Now that I am worried about engine failure, I wanted to get a clean burn, so I put them in my new engine. Perhaps I will replace them with something more common. For some reason, they stopped making the split-fire. I remember years ago someone sued the manufacture for whatever. I actually got paper work in the mail about it from the company probably because of my card and address and the type of lawsuit. Anyways still paranoid, but I drove it 25 miles yesterday and it is running and shutting off nicely.

steve
 
After a weeks worth of begging I almost have a response from the supplier. It is a soft denial. At this time all i can get is their file notes saying they are NOT GOING TO HONOR THEIR WARRENTY and someone was supposed to call me. That was in speaking to a sales person who is as far as I have gotten in their organization; that was about 4PM yesterday 1PM their time. Sill no call; although a question about causes and why I sent in all four piston/sleeve's. I explained that the damage and probable causes should be evident and that I was told by them to send back complete set since it was bought as set.

Let's see what today brings; I am going to plan golf.
 
Keep pressure on them, but don't get angry. When they know you don't plan to go away they may change their attitude. If it's not a manufacturing flaw, they need to tell you why it isn't. The term "product liability" is the legal term implying that their short comings could cause injury or death.

I forget, how long ago were they purchased?
 
CJD said:
Keep pressure on them, but don't get angry. When they know you don't plan to go away they may change their attitude. If it's not a manufacturing flaw, they need to tell you why it isn't. The term "product liability" is the legal term implying that their short comings could cause injury or death.

I forget, how long ago were they purchased?
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The hanks will report progress or lack y to here of.
 
They should cover, unless they can definitively prove it was detonation. An engineer with good magnification of the fracture should be able to tell the difference. A flaw and subsequent fatigue failure will leave beach marks on the metal. A rather rapid detonation failure will not.
 
Spoke to them today. Seems now they will cover the damage. They have a Morgan with the TR3 engine which has a piston. They will inspect tomorrow and call me. Now it begins negotiations as to how far they will go.
 
Sarastro said:
Where did you buy the pistons and cylinders, and what make were they? Sorry if you said that, but I couldn't find it in the thread.
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Bought from Moss. Don’t know manufacturers name. They are supposed to be back here on Wednesday.
 
Sarastro said:
I was afraid of that. Don't expect any help from Moss customer "service"; best to deal with the manufacturer directly, if you can.
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They did respond. They picked up two of the three costs involved. 1. Shipping to them. 2. Suppling replacement parts 3. Shipping back to me. I’m ok with solution.
 
Well, better than nothing. Be sure to look over the pistons very closely for casting flaws that could lead to a failure.
 
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