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iainskea

No 2 Cylinder lost all compression

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Well my smooth running didn't last very long at all since the timing belt change.

When I got back from a drive, the car seemed to be firing on only three cylinders, so I pulled a lead at a time and No 2 had no effect. Out came the plug and I checked it for spark - nice and strong. Next I fitted the colourtune plug and tried to set the idle mixture but no combustion flame at all. A quick check with the leak down tester and no compression at all in No 2. I checked the other pots and all ok. The air in No 2 seemed to be leaking out the exhaust pipe.

My first guess is I have a burned exhaust valve. I will take off the cam cover and check the valve clearances next. The other options are a hole in the piston (I hope not), but that would have had air in the sump from the leak down tester. The other is the head gasket - same again, air in the coolant. There is no milky oil.

How am I doing? Any other progressive tests I can do on the tear down towards the head off, I would be very glad to hear about.

Iain

Edited by iainskea

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Squirt a bit of oil into No 2 and run the test again. This will eliminate the rings as a suspect....if it still leaks at least it isn't the bottom part..:lol:

robert

Edited by matk

Robert Costa
1984 Turbo Esprit
Very Black!
2004 Lotus Elise
Quite Green! gone :-(

1977 S1 Esprit, in bits

1998 Lotus Elise S1, Azure Blue
Sydney, Australia

“The parts falling from this car are examples of the finest British craftsmanship”

Recommended procedure before taking on a repair of Lucas equipment: Check the position of the stars,kill a chicken and walk three times clockwise around your car chanting:" Oh mighty Prince of Darkness protect your unworthy servant.."

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Well here is the problem:

img0295th3.jpg

When I got the exhaust cam cover off, there was no valve clearance on one of the valves in No 2, and as you can see when I then got the head off - the valve seat has came out and jammed under the valve. The piston then gave it a touch up (a few times by the looks of things) and damaged the alloy head:

img0296en4.jpg

The piston has a nice 'character mark', but OK. I dunno, but the damage to the head looks like it can't be repaired. Bang goes a head.

I will copy all the info to my Lotus guy and see what he says.

Iain (sigh...)

Edited by iainskea

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Arrgghh! Sorry about that luck Iain, had you had any symptoms of a problem at all before this happened? Noises etc?

Artie


89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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Iain,

I've been following your trials and tribulations of previous incidents as I read the threads....are you sure your Lotus guy knows what he's doing??

Robert

Well here is the problem:

img0295th3.jpg

When I got the exhaust cam cover off, there was no valve clearance on one of the valves in No 2, and as you can see when I then got the head off - the valve seat has came out and jammed under the valve. The piston then gave it a touch up (a few times by the looks of things) and damaged the alloy head:

img0296en4.jpg

The piston has a nice 'character mark', but OK. I dunno, but the damage to the head looks like it can't be repaired. Bang goes a head.

I will copy all the info to my Lotus guy and see what he says.

Iain (sigh...)


Robert Costa
1984 Turbo Esprit
Very Black!
2004 Lotus Elise
Quite Green! gone :-(

1977 S1 Esprit, in bits

1998 Lotus Elise S1, Azure Blue
Sydney, Australia

“The parts falling from this car are examples of the finest British craftsmanship”

Recommended procedure before taking on a repair of Lucas equipment: Check the position of the stars,kill a chicken and walk three times clockwise around your car chanting:" Oh mighty Prince of Darkness protect your unworthy servant.."

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Thanks for your concern Robert, but I have 100% confidence in my mechanic. In this case, he has had nothing to do with the head except provide me with new valves and springs. I have no service history on the engine, apart from my own work completed.

I had the option to have the seats removed, head machined and new SS seats inserted, but the head seemed OK at that stage (and money was as tight as normal).

I have never seen this fault before with a valve seat. I have seen a burned valve and a hole in a piston, cracked rings, but never a seat coming out.

I would be interested in views on how this happened - seen it before?

Art: The only symptom was miss-firing on No2, and backfire which would make sense with fuel/air making it into the hot exhaust pipe.

Iain

Edited by iainskea

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I've never seen it happen either, but I have heard of it before...at that time it was attributed to an overheated head, probably due to weak mixture/pinking/bad cooling.

Maybe that might help understand what happened.

Robert


Robert Costa
1984 Turbo Esprit
Very Black!
2004 Lotus Elise
Quite Green! gone :-(

1977 S1 Esprit, in bits

1998 Lotus Elise S1, Azure Blue
Sydney, Australia

“The parts falling from this car are examples of the finest British craftsmanship”

Recommended procedure before taking on a repair of Lucas equipment: Check the position of the stars,kill a chicken and walk three times clockwise around your car chanting:" Oh mighty Prince of Darkness protect your unworthy servant.."

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Today things are looking a little brighter (glass 10% full outlook...)

Steve at the Elan Factory is quite confident that the head can be repaired with an oversized valve seat. He is sorting a local head specialised machine shop with a 'Serdy' machine to check the flame face and cam faces for straight and flat, along with a porosity and hardness test. A full inspection of the rest of the valve seats is planned.

Cool.

If not, I'm going to get one of these: :lol::)

http://www.elanfactory.com.au/pdf/product_...nder%20head.pdf

Oh, I dropped the head on the ground, oh, I dropped it again...heh heh heh

Edited by iainskea

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tell the wife to pick a room, then paint the living crap out of it and buy her a nice meal and a new dress and shoes, then when you have done all that go and buy the head, she wont give a damn then!

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Guest Troy Halliday
tell the wife to pick a room, then paint the living crap out of it and buy her a nice meal and a new dress and shoes, then when you have done all that go and buy the head, she wont give a damn then!

He does make a good point :)

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I would check your flow on your water cooling system too. Your trouble could be caused by the head overheating as previously mentioned, but could be due to poor cooling. Just a thought but I would say worth checking just in case.


 

"Belief is the enemy of knowing" - Crrow777

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I've seen a valve seat drop before - much less exotic though a 2.0 ford pinto engine. No unusual noises or overheating prior to it dropping out. Took the cam out as well as the head. Fortunately they were very cheap down at the scrapyard!

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Hi Iain

Back in Perth & have only just read your thread!

I thought it sounded & felt worse than just an exhaust gasket, sorry mate - we went half way to the Gold Coast and back with it rattling away under the valve. Should have done a lot more damage than that - shows how tough the lotus engine is!!!

Get it to a head specialist before you order a new one, some of them can do wonders. Your mechanic will probably shop it out anyway. New heads are very expensive.

Good luck with it

xisab B)

post-4093-1202212459.jpg

Iains Esprit in the Aussie bush dropped valve seat and all

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...and there you have it, the engineering shop called and said the head is lost - due to a failed hardness test. He said it measured 59 Brinell (minimum is 65).

sigh... :D

Out with the paintbrush and nice dinner for the missus.

Iain

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Iain,

Sorry to hear about your head! Bad timing as last week there was a complete engine on ebay for about


REHABS FOR QUITTERS!!

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Bit of an update here - I opted to have Steve arrange for the machine work to cut the valve seats / grind faces / test etc . The head is ready for me to collect on an opportune visit to Melbourne in two weeks time.

As an aside, he sent me a cool pic of a turbo esprit engine he is rebuilding - check it out:

2004010100005800061sr5.jpg

Iain

Edited by iainskea

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Good to see progress Iain - why is it that things Lotus take so long?

Two weeks will give you time to crawl under and check all those body to frame bolts I am sure you have some loose ones - after taking mine for a drive when I got back to Perth I am sure yours needs looking at - mine was so quiet to ride in compared to yours. Check it out.

xisab

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Hi xisab,

I'm on the job. I am taking full opportunity of the access improvement while the head is out and today I did some wiring tidy up that you don't usually see below the carbies. I have already tightened the chassis bulkhead bolts (both were loose).

The highest priority for me is to rectify the cooling system temp measuring system, and I have ordered an electronic system that I can discreetly fit below the binnacle. This system independently (to the smith gauge and sensor) monitors the temp and allows for up to three fans to be progress switched on at rising temp.

After this is installed, I will be much better placed to assess the adequacy of the cooling system - which is what I am blaming for cooking the head.

The more the delay is from Lotus - the more I will get done! heh heh heh

Iain

Edited by iainskea

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Good to hear Iain- those clanks & bangs should be gone now.

I have also played around with my cooling fans because of our higher ambient temps, and because of the added air conditioner. As I said on another thread I added a central fan as mine only had two. I also wired these myself with four extra relays and warning lights so I know which fan is running. I also added a manual overide switch so I can run all three when I want to.

post-4093-1206187491.jpg

The newbie looking one is the extra.

post-4093-1206187524.jpg

The switch is the square one and the LEDs are Red for radiator fans/Amber for all on manually/Green for aircond condenser fan/black bezel red LED is the immobiliser.

All on the windscreen finisher & out of my normal line of vision so they don't annoy me while I'm driving - easily seen with a slight tilt of the head. Best of all no crawling under the dash to fit.

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Great photos Lionel, three fans are a must.

I am also scouting around for a new battery - one that fits but also has the max amphrs.

Iain

Edited by iainskea

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Great photos Lionel, three fans are a must.

I am also scouting around for a new battery - one that fits but also has the max amphrs.

Iain

Hi Iain

Just had the same problem - had to replace the battery, I used the same as last time seeing how that one lasted 8 1/2 years - an Odessy PC925 - they have a steel case and brass & stainless steel posts & bolts.

I also have a built in charge & maintain which also just fits into the Lotus battery box & plugs into the 240V all the time it is parked (most of the time)

xisab

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