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Discussion Starter #1
Well Pickles... My motor popped this morning... but in a way I haven't seen before... I went to the dyno so that I could do some tuning... I did 8 runs back to back to get some nice and hot base lines on the tune I've been running... All is good...

So the car was spinning down from the 8th run to an idle and then it just dies. I'm thinking, "that's not good." It didn't make any noises that were odd, no drame, the run looked clean--- it just died...and that's something it doesn't do... Then it wouldn't start.

Pulled the plugs, they look great (of course:)). Do a compression check from 1 to 4, 185, 185, 0 and 185... Ah nuts... but I'm still thinking something is up, as the #3 plug looks good, and normally they melt when the piston does... Something still isn't adding up... So I look down the plug hole with a flash light and find that the intake valve is shrouding the plug hole and the valve doesn't move when the engine cranks.Dang... Then I'm thinking, "well shoot that #3 cam problem hit me and my rocker is broke or something"...

So I limp the car home with the #3 plug pulled, which is what it took for the car to run. Then I flip the clam up and within in 5 minutes, I've got the valve cover off to find that my cam looks good, but there's another problem. Maybe you can tell in the pics...

Interestingly enough, you might think I spun the motor... But not really. In each run, the dyno shows we never exceed 8550, which is consistant with my logging as well... Granted 8550 isn't low, but it doesn't seem off the charts and it's what most do on the dyno (Including me in the past)- run to rev limit...

So I obviously dropped an intake valve, which I can only assume happened because the valves floated. Either that or a retainer gave way, but i doubt it...My take away from all this is that the stock springs are weak and we may all have been or are on borrowed time by revving the car to 8500. BTW- Engine has about 12,000 miles...

So now I need to pull the head. I'd like to do this in the car (the clam is up so things are easy to work on).
Manny, Boosted, litman, John, LR, ???, any you guys have any tips for doing this job in the car? If so, I'm all ears... I consider myself an above average mechanic, but I've never had the 2zz apart. John, I've got your service manuals, thanks!

Best,

Phil
 

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Well crap. 1/2 the KC fleet is going to be down soon as ours is patiently waiting on a date with the body shop.

If I could possibly help, I would.
 

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Discussion Starter #6
So here's the latest...Absolutely everything is off other than the head. Cams are out, marked, etc...So I'm at the crossroad of wondering if the surgery can be done with the chain cover on... if it cannot, the engine has to come out:( as the frame is in the way to remove atleast one of the bolts that goes through the chain cover and into the block.bummer... I'm stopping for the night and will pull the 10 head bolts tomorrow AM and see what happens. I hoping that there aren't any locating pins in the timing cover that will keep this from being easy...

Only one valve floated and that sucker is bent! and I mean bent. The stem looks like a ? mark...

I've decided I need some headers. The stockers neck down to ridiculous proportions. There must be some good hp locked up in those for a blown and tunable car...

Interestingly enough, I've rec'd PMs (no names, their business) from a few others that have had the same thing happen... Also only one valve dropped, the other intake is fine. It's like the retainer just popped off. I mean the valve is way down in the hole... I've been through this type of thing before on a float, but I've never had the valve appear to drop all the way down like this.

Thanks all.

Best,

Phil
 

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Discussion Starter #7
Wow.....now that's 3rd time I've seen the same exact thing happen......Phil if you need some tips for getting the head off give me a call.
THanks!

Do you know if it can be done in the car with the chain cover on? I'm ready to go with taking the head off. THought I would cruise manual for a spell and see what I find...

Best,

Phil
 

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shay2nak
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wow, that sucks. Is there anyway to prevent this from happening or is it kind of a freak failure?
 

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Sorry for the mishap.

Group buy ... valve springs

I could swear a few people had the head off without pulling engine.
 

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Discussion Starter #11
Thanks Guys, looks like the cover must come off due to the chain tensioner. It bolts to both the head and the block:wallbang:

The pivot bolt for the belt tensioner is the turkey that makes pulling the cover a job hard. It's so long that it hits the top of the frame before it comes out of the block. Spoke with Casey about it and he simply jacks the engine up from the bottom to tweak the motor mounts, thus giving the room needed. I'll give that a try and perhaps remove a couple motor mount bolts so that it might pivot up easier allowing the bolt to come out- clearing the frame.

I'm giving some thought to just buying an assembled head from MWR. Looks like they sell a head all ready to go with better springs and SS valves for 1,100. So they're charging about 500 for machining and assembling. That's not much more than the local shops would hit me up for and then there's some convenience in just having a turn-key head and not having to run all over town...

As mentioned by Frank, Casey, and some others in the past, it does seem that the these cars have some serious potential to float the valves well below 8500, so be careful folks. It's lot easier to replace just the springs than it is to do what I'm having to do...

Shay, this has happened to enough people now that we know it's not an abuse issue. It happend to one guy sitting at a stop light- car just died. Maybe his valves floated prior and slightly bent, and the valve finally froze at the light... In my case, only one valve let loose, but perhaps more floated. I won't know until the head comes off. The important thing is that I've never spun the motor or missed a shift. I don't make a habbit of visiting the rev limiter, but it does get used. So did a retainer just decide to let go or did the valve float causing the retainer to let go? Hard telling for sure, but it was probably float. The best thing to do it just replace the springs now before something goes south (like a valve.lol). They're a lot easier to replace in an otherwise running car since the job can be done just by pulling the cover and cams out of the car...


Best,

Phil
 

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Wow.....now that's 3rd time I've seen the same exact thing happen......Phil if you need some tips for getting the head off give me a call.
Casey,

Have you ever seen this happen with the stiffer springs installed? I just bolted 1.6L of twin-screw joy on my car after 2 years of Turbo lovin' and so far, so good..... It can pop if it must, but I would prefer after my 6th run at nationals....
 

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Not sure if this would help, but would an EGT (exhaust gas temperature) gauge be useful to see if things are getting finnicky inside the engine before catastrophe?
 

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Phil.. I have not seen this issue arise on the Elise, but some people I used to hang out with back in the day... They were into Celicas.... And at least 2 of them had to rebuild their motors due to floating valves.. I would contact Lotus/Toyota/Yamaha just to see what they have to say.. After all its not an isolated failure.
 

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Ouch. Sorry about your engine. I hope everything works out. I would love to see a pick of that bent valve and more of the carnage. Sounds like that head from MWR might be a good way to go.
 

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00 MRS - 2ZZ NA
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Wow, sucks to hear about your car! Good luck with the fixing!

Not sure if this would help, but would an EGT (exhaust gas temperature) gauge be useful to see if things are getting finnicky inside the engine before catastrophe?
Don't widebands make EGT gauges obsolete by always keeping the driver informed of what your exact A/F ratio is, rather than guesstimating what's going on with the engine by looking at a EGT gauge?

That was my understanding on the issue, so wasting gauge space and money on a EGT gauge sounds useless to me if it's inevitable when the car's pushed.
 

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EGT only takes about 1/4 inch for me TADTS

 

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I will run EGT and not a wideband permanently in the car because the only gauge in my car will be the defi link display. I will have it monitoring, oil pressure, oil temp, fuel pressure, water temp, and EGT.
Defi - Defi-Link Display


Phil, sorry to see that happen, good luck with the repairs.
 

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If I recall correctly....after the first couple production years of the celica gts, toyota lowered the rev limit of the motors......a couple toyota engineers told me this done to correct a problem similar to this one
 

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Welcome to the club... Motor #2 which I just broke in blew on me this weekend. I had MWR valves and MWR higher rate springs... Not sure the extent of damage but the motor sounds like ass and cylinder #1 has no compression.
 
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