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Discussion Starter #1
I guess Engine #3 ?? Or toss in the white flag and scream uncle?

Dropped a valve this afternoon doing just a simple 3K-8K 4th gear test run, happened on my 2nd run (not even at the track, just local street). Got to about 7,900 and blaaaaaaa -- all sensor readings good except EGT #4 600,500,400... ****!

Pulled the plugs, #4 was wet but no oil, but then I see the valve ... what I see the valve!!! Ugh.

Rev limiter was set to 8100, didn't even reach it. Wonder were Lotus get off thinking these motors can handle 8,500 for even 1 second, let alone 2 seconds.

Maybe this is the excuse I need to finish up a monster motor, I was just hoping it would NOT be so soon after finishing my 2nd motor.

I guess it's time for some of these: valves, springs, retainers -- or go with a new stock head and valves for $500 and call it a day.
 

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Did you use the monkey wrench valve spings on #2
 

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WTF wasn't #2 fairly well built also??? Any idea on what the failure point?
 

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Discussion Starter #5
#2 used the same head/valves/springs/retainers that was on #1 engine ... and that might be the problem but I had gone over the head and all appeared upto snuff.

My #2 engine was pretty much stock with a few minor changes (ARPs, RLS IC, and was less boost) and I lowered rev limit from 8500 to 8100.

I need to evaluate what I want to do, engine #3 is much sooner than I had planned. The valve hasn't actually dropped so I'm guessing it's just bent. If I'm lucky the cylider walls will be ok just the piston will most likely be damaged. I'm concerned that the piston is not moving when I crank it over sooo....

I'll pull it out this weekend and go from there.

Rob.
 

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I am curious. If something like this happens and the car is out of warranty, will car insurance pick up the tab if you have full coverage under compherensive coverage? or you are on your own?
 

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I am curious. If something like this happens and the car is out of warranty, will car insurance pick up the tab if you have full coverage under compherensive coverage? or you are on your own?
While there might be some exotic insurance coverages available out there, I don't believe the average insurance policy will cover mechanical failure on the car, even under Comp.
 

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Rob, that's seriously bad news....

I'm on engine #2, after my rod/bearing #1 blew from oil starvation caused by blow-by. I had to replace the short block and went with a stock block, but I did upgrade my valve springs, as I heard they were prone to failure....was that the cause of your engine blowing?
 

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shay2nak
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how much whp?
 

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That sucks!

Don't give up! Let it be a reason to build it even better.

Keep us posted.
 

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Can't really blame Lotus when you used took parts from your previous blown engine, which could very well be the reason the new engine let go. Also, you can't blame them when you've modded/retuned your engine however conservative you may think it is.
 

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Rob...terrible news. I feel ya, I been there. Just build your motor, do it right - ask Kris to personally build it like he did mine. Believe me, you'll be knocking yourself asking why you didn't do this earlier. Since you have an EFI and want to (assuming) keep using it, have Kris do everything. Otherwise I would say...Charlie time with something based on the VF kit.

I just don't think the stock engines are meant to live that long on the track no matter how many other people have modded it without problems, it will happen again.
 

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If your turning the engine over and that piston isn't moving then you threw a rod. When that let loose the piston probably flew up and took out the valve. You'll definitely want to pull everything apart and check for block and cylinder damage as well as rebuild the head. Sorry to hear about your engine, but it's a good excuse to build one up with rod's, pistons, oil pump gear as well as putting together a bulletproof head. If you don't have the funds for that at the moment you could just find a used 2zz and throw it in there for the meantime, build the other engine (if it's salvageable) then swap them out again at a later date.
 

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Rob,
Sorry to hear about #2.
Breakout the flashlight and double check for piston movement.
Breaking a rod would be quite odd.
 

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Mulholland>SCC
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Insurance does not cover mechanical failure. They do however cover car fires.

I am curious. If something like this happens and the car is out of warranty, will car insurance pick up the tab if you have full coverage under compherensive coverage? or you are on your own?
 

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Rob,
Sorry to hear about #2.
Breakout the flashlight and double check for piston movement.
Breaking a rod would be quite odd.
I was thinking that as well, but reading your post got me thinking again. It is possible that since the engine was rebuilt that the connecting rod end cap was not properly torqued ie over or under and came loose or the bolts may have sheared off. Could also have been some damage or weakening of the rod end cap or bolts due to the failed bearing on the original engine as well. Some times damage isn't noticeable and **** happens. This would also account for the rod not punching it's way out of the block and the fact that the engine can turn over with out binding.
 

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Vendor
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My bet is also the best case scenario:
-broken intake valvestem at the retainer groove
-Bent intake valve toward the center from the drop
-Piston and cylinder is ok
-Fix is easy and simply requires replacing the head with MWR stage II head.

... Anyone care to take that bet? :D
 

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My bet is also the best case scenario:
-broken intake valvestem at the retainer groove
-Bent intake valve toward the center from the drop
-Piston and cylinder is ok
-Fix is easy and simply requires replacing the head with MWR stage II head.

... Anyone care to take that bet? :D


Me :p
 

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Discussion Starter #20
Thanks for the support folks.

I'll double check the piston movement tonight as that will determine if I just pull the head or the entire motor (again). I'm hoping it's just a bent valve from the tip breaking, which I believe is pretty common on the stock valves. When it let go it was very silent, nothing ugly and I was able to limp the car home.

If it turns out to be just a bent valve and no cylidner wall and/or piston damage then I'll probably just get a Stage 2 head from MonkeyWrench including cams (pre-setup).

Not blaming Lotus since this isn't a Lotus motor, it's a Toyota ;). But doing a quick search and A LOT of folks seems to have similar valve tip breaking problems resulting in a bent valve. I was warned about weak Toyota valves and hence why I dropped the rev limit down to 8100 from factory spec of 8500. And I'll admit, I frequent that rev limit on track. But of all the "street" cars I've owned, tracked, and raced over the years, this motor seems to be the most fragile. I'm not sure how Lotus define a car as "track worthy", but it clearly is far from my definition -- and when Lotus use terms such as "Track Package" as an option -- they clearly have some other meaning. I'm pretty sure Lotus are well aware of the weakness of the 2ZZ -- isn't that why the Cup Cars (track only) rev limit is 8K rpm and not 8.5K like it is in the street legal cars?

On this engine (#2), the replacement short block was new from Toyota and I'm not running crazy boost -- I don't have the exact wHP number but I know it is considerably less that Motor #1 (which was 255 wHP on 91 octane on a 2.5" pully - I'm on 3.0" pully pushing max 10 psi but normally around 8.3-9.3 psi). This problem isn't boost related nor is it tune related, it's RPM related.

Too much time and money invested in this car to set it on fire ;) ... besides the rest of the car is great, it's just the motor (and I assume eventually the tranny) that is a very weak link in what could be an outstanding track/street car. I do have my limits on how much money I'll keep tossing at motors (sorry can't afford Kris). I don't mind doing annual motor freshening, but I do mind doing them monthly (I'm not racing the car, just some casual track days and time trials).

Anyway, I'll get Engine #3 back together and go from there.
 
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