[willhogan]

Leak down test was done today on my motor with the compression issues, Upon further examination it turned out to be Cylinder 2 with the problem. Valves and all other Cylinders checked out fine. #2 is believed to have a bad ring hence the 90-100 less compression. My question is this: once the motor is torn apart should my tech find that the cylinder bore is not scarred or damaged in #2 can he not just replace the ring's and re-assemble. It's my understanding that the block can only be sleeved and it's not possible to machine the block.

What in the name of god could have caused a bad ring after 14,500 km? I did not do a baseline or compression test on the motor prior to installing an SC. The SC at the dyno showed very conservative A/F ratio's and I'm quite certain that is not the cause.... Any suggestions?

I purchased the car with 8,400km, is it possible that the prior owner did something to cause this? Can driving the **** out of this motor in cold Canadian weather for 6,000km do this? I always waited for it to warm up but still. I'm lost for ideas....

I don't want to build the motor again without correcting a possible problem and having the same thing happen.

Are there things I should look for when torn apart?

If the bore is ****ed should I buy a new OEM block or sleeve it with better pistons?

 

[Jim-C]

What leak down numbers did you come up with? Percent of leak on each cylinder.

Did you do a compression check too? I'm wondering what the numbers might be. I'm going to check my car and track the compression and leak down over time. My car runs fine, just want to keep an eye on things.

 

[MaineLotus]

If I were in your situation, no question - sleeve and Mahle pistons. You'll have a better setup and it will cost you around $1,400 for Darton sleeves & installation and a set of Mahle pistons.

Curious... You started a thread a few days ago that your engine was blown, why are you surprised after learning about the #2 failure? Most likely it's not just a ring, the piston ring lands have probably collapsed, scaring the cylinder wall at the same time. You won't know for sure until the head is pulled.

 

[z driver 88t]

Ring land?

Please keep the thread updated. I'm really considering a FI Elise this summer. I'll be curious to see the actual failure. Most of my experience is in forced induction Nissans, but in the turbo 240SX world the most common failure is a cracked ringland caused by detonation.

I've been lurking this forum for awhile researching FI Elises. There seems to be a surprisingly low number of "growing pain" engine failures related to FI applications, especially with such a high compression engine on a low volume vehicle.

 

[Mag]

if the ring was damaged to the point where it has caused damage to the block, you will need to re-bore, if the damage is slight, then same size pistons can be used with new ring, otherwise need to bore out and sleeve, or over sized pistons (if available).

Since the engine needs to be torn apart anyways may as well refresh the bushings and replace all rings. incremental cost will be small relative to overall cost.

if it's just compression, and you aren't finding oil burning white smoke out exhaust, then damage is prob slight. If former, than there's a chance of crank shaft/rod damage if piston's been allowed to jiggle around causing damage to all other moving parts.

sorry about news, that always sucks.

 

[fzust]

Leak down test was done today on my motor with the compression issues, Upon further examination it turned out to be Cylinder 2 with the problem. Valves and all other Cylinders checked out fine. #2 is believed to have a bad ring hence the 90-100 less compression. My question is this: once the motor is torn apart should my tech find that the cylinder bore is not scarred or damaged in #2 can he not just replace the ring's and re-assemble. It's my understanding that the block can only be sleeved and it's not possible to machine the block.

What in the name of god could have caused a bad ring after 14,500 km? I did not do a baseline or compression test on the motor prior to installing an SC. The SC at the dyno showed very conservative A/F ratio's and I'm quite certain that is not the cause.... Any suggestions?

I purchased the car with 8,400km, is it possible that the prior owner did something to cause this? Can driving the **** out of this motor in cold Canadian weather for 6,000km do this? I always waited for it to warm up but still. I'm lost for ideas....

I don't want to build the motor again without correcting a possible problem and having the same thing happen.

Are there things I should look for when torn apart?

If the bore is ****ed should I buy a new OEM block or sleeve it with better pistons?

Will, I believe based on the race car I've run and the research we've done that the #1 cause of accelerated wear or failure is lack of proper oiling. The clearances on the 2zz main bearings are tight thus the need for the 5w in the 5w40. I've known several folks that have run the the cars at the track and through hundreds of auto-x runs with no issues, but they all have had very careful watch over oil level. Randy Chases car has the moroso pan, as does mine. Additionally, I have the accusump, which is excellent.

As far as the sleeving vs. new block, I read Toyota's SAE paper on the 2zz talking about the MMC(metal-matrix composite block) vs. sleeves. The advantages are: superior cooling, detonation resistance, and physically tougher than the iron sleeves. There are plenty of folks doing both, so either will work, I am just a bigger fan of the non-sleeved approach. It might be more cost-effective if the block is scored to sleeve it, I don't know.

 

[MaineLotus]

Ring land?

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