For ZE owners that have suffered dropped valves..

Tunes67 · Post by **Tunes67** » June 14th, 2007, 7:39 pm

Bump.. come on guys.. I know there have been more than 2 cases of this happening LOL

Tunes67

94mx3precidia · Post by **94mx3precidia** » June 14th, 2007, 7:57 pm

today was the fist day i ACTUALLY drove my car, all the other times were reversing up and down my driveway making sure things worked. Driving my first standard car to school was fun. I have to say that i only mishifed once and that was second into neutral comming out of a stop sign, i saw the rpms rush towards 8000rpm. I was a little scared but it was ok, i didnt want to bend a valve. I would occasionally mishift, say like going from second to third i would accidently put it in 5th and i almost stalled my car. All in all, i like these cars, there small peppy sports cars that people misunderstand. I saw one of the guys i work with today and he said: is that your car? (as i was getting my e-test done) and i said ya..... im dring it. and i told him it was a v6 and he was like wow, too bad its a mazda. I told him to go to hell and i drove away squealing the tires. he drives an accord........

Anyways, i hope i end up never bending or dropping a valve cuz ive heard around that they can really mess things up.

Post by **Mooneggs** » June 15th, 2007, 9:43 am

I wasn't sure if I should post... but I have not dropped a valve yet and I have a curved neck IM, and KL01 cams... I have misshifted before and revved past 8k... I've probably done that 5 times total over 4 years. since I have no rev limiter on my ECU I have always tried to be careful since I knew I could do major damage to the engine if I overrev.

I used to shift around 7200-7500 for all my shifts while racing (for over a year)... until I realized that the powerband drops off around 6600... I've also gone pretty fast (154 mph top speed so far) and I've heard of others messing up cylinder 6 or something at top speeds? Never had an issue out of the motor and it has about 100k on it now... and I still drive the crap out of it a couple times a week:roll:

anyways do I fall in the category of maybe not dropping a valve since I have the curve neck + kl01 cams? or am I just really lucky?

Tunes67 · Post by **Tunes67** » June 15th, 2007, 10:50 am

Dropping a valve is about the same as Motor go BOOM. If you had dropped a valve.. you would know it.. the engine becomes unusable. Its most likely ruined beyond repair.. depends on how much damage occurs when the valve drops.

Tunes67

Jay72 · Post by **Jay72** » June 16th, 2007, 4:02 pm

Sorry if this is a stupid question but what are the symptoms of a dropped valve? Noise, performance, would car still be drivable?...

Tunes67 · Post by **Tunes67** » June 16th, 2007, 4:10 pm

Well there would probably be some really nasty sounding noises coming from the engine. The cylinder where the valve dropped would have 0 (zero) compression. The engine may or may not continue running (depends on the damage that occurs.. but if it does stay running.. it would obviously not be running right or well.

Tunes67

mx3autozam · Post by **mx3autozam** » June 17th, 2007, 1:43 am

The engine would still run on 5 cylinders, but you would know, just imagine it midfiring the 5th cylinder or not giving that cylinder gas, it would be rough. would probobly be loud since teh piston and valve would be kissing eachother all the time.

I ahve probinator ECU.f i rev just past 7500 theres a fuel cut. as for why do i go to 7500rpm. at the track i ussually wind 1sta nd 2nd to there tgen shift 3rd and around 6700. on the highway i can see my speedometer move when i'm going to 7500

babyblueMX3 · Post by **babyblueMX3** » June 17th, 2007, 11:08 am

as far as symptoms are,
major performance loss and weird noise. Once it cracked I was still able to drive with it until I parked it where it didn't want to fire again.

hgallegos915 wrote:I dont think i have yet heard of anyone dropping a valve on the kl-01 cammed zes. Supposebly they are the exact same valve train? Im swapping out the retainers anyway once i swap the cams. The car i rarely drive anyway. I know it happens to most people that over rev their car alot. Ive had mine for 10 months, a few missed shifts and im still good (crosses fingers)

no they are not the same. KL01 camed ZE's have the same heads, thus the same valve spring, and retainers. Valves are the exact same though.
BOTH kl31 and kl01 camed ZE's have the same EXHAUST valve train as the klde (springs, retainers, valves).

more specs to be found here : http://www.mx-3.com/phpbb2/viewtopic.ph ... c&&start=0

babyblueMX3 · Post by **babyblueMX3** » June 17th, 2007, 11:26 am

just to put some picture on this :

Jay72 · Post by **Jay72** » June 17th, 2007, 1:06 pm

hmmm... thanks, guys. My engine's still strong and I've driven 3 hours up north a few times but twice in a year now I've overtaken someone in 2nd and when I came to slow down my engine would start to "choke" and I would hear a nasty noise like a baseball card in bicycle spokes (except metal sounding) when I would accelerate. After turning the car off it would be gone the next time I used it. I guess a compression test is the first step to a diagnosis. Dropped valve... big job? Not recommended for a DIYer with very little knowledge or experience?

babyblueMX3 · Post by **babyblueMX3** » June 17th, 2007, 10:25 pm

Jay72 wrote:hmmm... thanks, guys. My engine's still strong and I've driven 3 hours up north a few times but twice in a year now I've overtaken someone in 2nd and when I came to slow down my engine would start to "choke" and I would hear a nasty noise like a baseball card in bicycle spokes (except metal sounding) when I would accelerate. After turning the car off it would be gone the next time I used it. I guess a compression test is the first step to a diagnosis. Dropped valve... big job? Not recommended for a DIYer with very little knowledge or experience?

hard ? depends on your skills. Same thing as changing a head gasket + work on the head.
Yeah compression should the first thing, you should go 0 on the one you scewed (if you have screwd it, your problem could be something else). If you have very little knowledge about this, I'd take it to a mech.

Jay72 · Post by **Jay72** » June 17th, 2007, 11:50 pm

thanks.

e11evon · Post by **e11evon** » June 19th, 2007, 1:39 am

is there any way to prevent dropping a valve...like a rev limiter...I am looking to get a ZE within the next 2 months...I have hit the rev limiter about 3 times on the K8 (just reving in the driveway...trying to find a reason to buy the ZE now),a nd it still runs like a champ...I am gonna run the str8 neck ZE with the Milenium IM...I have heard it is best to swap out the retainers and valves before installing the ZE, to get a better life out of it, but what Valves and Retainers do I use?

Cy · Post by Cy » June 19th, 2007, 2:09 am

so basically the point is if you pickup a ZE ... get a headjob done with some Ti retainers

MoRf · Post by **MoRf** » June 19th, 2007, 2:26 am

i dont think your going to get much from the poll on this one , it seems the straight necks are driven harder so theres obviously going to be more blown straight necks.

the cheapest solution to the problem is don't rev past 7000 with out building the head

MX-3.com

For ZE owners that have suffered dropped valves..

What ZE's drop valves the most often?