Urgent advise needed - smoke galore

[Enright]

As I recall, Paul's problem was caused by something very nasty getting where it shouldn't.
I think the conclusion was that a spark plug may have been dropped before fitting and the electrode came off, got lodged between a piston and it's bore, and destroyed both.
Of course, you don't just bore out 1 to correct the problem - they all have to be done equally.
He had someone visit his house with a machine to bore and hone the block, with the engine (obviously in pieces but) still in the car. Paul still owns the car and is active on the forum - it would be worth having a thorough read of his thread and then maybe asking him a few questions direct about where he got his parts. I reckon that oversize rings will be specialist items and doubt Rockauto will be able to help.
Edit: the manual says that 80.00mm is the standard size, so you may be ok - you'll find this info on P11 of Part 1 of the Service Manual - have you downloaded it?
My worry would be what caused 3 out of 4 to have been so severely damaged, and what other problems there may be in the engine.
On the other hand, I can tell you that after Paul had this initial (albeit massive) problem, he has had great experiences with his car since. So there is a light at the end of the tunnel.

[bobbrown]

Bad news

You will need more than a set of rings if the bores are damaged.
Not sure what you mean by fit new sleeve as the bores are not sleeved to correct any damage in the bores you need to rebore to the next available size.
This can not be done with out first getting a set of pistons and rings as they are graded, standard pistons are in three sizes 80.0/80.01, 80.011/80.02 and 80.021/80.03 no doubt the oversize ones follow the same pattern available in + 0.5 and + 1.0 mm and it is normal to bore to the piston actual size.
Bore to piston clearance is small hence the need to bore to the piston size, turbo engine bore to piston clearance is 0.058 to 0.078 mm.
If the bore is damaged you wil need to measure it in three positions down the bore and front to back/left to right to establish if + 0.5 mm pistons can be use or if you need to go to +1.0 mm.

Not going to be a low cost fix as pistons and rings are likley to be £250 to £300 and that does assume you do not need gudgeon pins and if it was me I check the crank and replace all the bearings and probably the oil pump as a matter of course.
While the engine is in bits I would also overhaul the head.

Also you will need to establish the exact reason for the failure as you do not want a repeat.

[dapinky]

Peck,

Bad luck on the diagnosis - but at least we now know what we are looking for........

A couple of things (for what my opinion is worth), but are the pistons melted, cracked or what??

As Bob says, there will be a root cause which needs to be dealt with - if the car runs high turbo boost (or even normal boost, but with other problems) then the mixture in the engine can become too lean and you will get severe temperatures in the bores and the pistons can go into meltdown (very quickly). This could be a problem in a number of areas, eg ECU, injectors, O2 sensor, fuel quality and loads more - you need to get enough petrol into the cylinders to match the amount of air being forced in.

Another cause can be blocked oilways - the Turbo engine differs from the NA in a few ways - one of which is the design of the actual piston, and the way it is 'oil cooled' by basically spraying oil from underneath to help cool the pistons.
As such, OE NA pistons cannot be used in a turbo model. (different compression ratios too).

Trying to find new pistons is a nightmare - i know, i looked!!! and they are only available in limited sizes. (and at stupid prices, as the rings are sold seperately)

Now you've had the bad news, there is a way to do it.......

As Bob says, the rest of the block needs to be checked to see if there is other damage that needs to be machined out (crank bearings). Then get all 4 piston bores machined to the same size (minimum that you can get away with to get them all the same, and perfectly straight/round.) - but DON'T WORRY ABOUT THE ACTUAL SIZE THEY END UP!!!!!!!

Many older people on here will remember Robbie The Robot, but he doesn't seem to post much anymore.
However, he supplies individually made forged pistons to an exact size to fit your bore. There is a lead time of 5 weeks or so, plus the fact that they come from USA, but they are good bits of kit and can be made to whatever spec you ask for.

There may well be somwhere more local and / or quicker, but they are the ones I'd recomend (as I say, when my old engine went bad, i spent a long time tracking down the bits needed to re-build it as cost efficiently and properly as i could).

[Enright]

Where the hell did my last post go?
It shows up on my profile but when I try to jump to it, Bob's is the first on the list.
Took ages to write on my phone too.

[Dave Eds]

I must say that confused me too Neil - guess you'd better write it all again (or not!).

It showed as the last post timed at 10.48 even though Bob's post was there for all to see!

[bobbrown]

I did see your post as well, was there as I saw it but only briefly then there it was .........................gone.

dapinky,
the pistons from Robbie The Robot are a tad on the expensive side at £390.00 a set but they are forged so thats a good thing, then what about the rings, do they come with rings if so the price is not as bad. SJ lists pistons +0.5mm do not know if they are available or not but at £40.17 plus a set of rings £26.15 that makes £265.28 for a set of 4.

If the pistons are burnt then it is a sure sign the engine has run lean and detonation has occured this only take a very short time, may be a second, and the very high temperatures will destroy pistons it can also damage conrods and bearings (when built check the piston heights are the same). The knock sensor is supposed to reduce this risk of detonation so if they are burnt another bit to check.
If there are lots of marks on the piston crowns and head then something has entered the engine, I always find it strange that foreign objects always seem to go walk about and cause damage on more than one cylinder. If it is a foreign objects then you need to establish what it is and where it came from. Think Pauls was a bit of spark plug!

SOme pictures of the damage would help identify what has occured.

[racerstev]

If I were you I would call the machine shop and tell them to wait for the pistons before they bore the engine. If you go
with the JE pistons ( forged ) they take a very differant clearance then the stock cast pistons do.

Pictures of the pistons will tell us what happened..


Steve Lockett

[Specky]

Just play safe if you use Rock Auto, because they do sell the N/A pistons as well. (if you require pictures of them just to ensure you don't get the wrong ones, just say)

I managed to obtain the last Lotus N/A pistons (and N/A Gudeon pins) in the normal size and oversize varients.

My top tip is to weigh the pistons (and assembles) when you build them up, If you so wish you can ammend the weight on the three heavier pistons and thus ensure the balance of the engine will run like a sowing machine.

TTFN

[lotusdriver]

Bad news

You will need more than a set of rings if the bores are damaged.
Not sure what you mean by fit new sleeve as the bores are not sleeved to correct any damage in the bores you need to rebore to the next available size.
This can not be done with out first getting a set of pistons and rings as they are graded, standard pistons are in three sizes 80.0/80.01, 80.011/80.02 and 80.021/80.03 no doubt the oversize ones follow the same pattern available in + 0.5 and + 1.0 mm and it is normal to bore to the piston actual size.
.

Those are finished bore sizes rather than piston sizes, the standard pistons are all under 80mm.

The A, B and C grade pistons mentioned in the service notes were discontinued by Lotus well over a decade ago (you could at one time request what grade you wanted when you ordered, there wasn't a separate part number as such) The three grades were then replaced by two called AX and CX which overlap the previous grades.

Piston (not bore) diameters are as follows

AX 79.945-79.959
CX 79.960-79.966

The oversize 0.5 and 1.0 only come in a single grade

There is nothing wrong with sleeving, and if only one cylinder bore is damaged it can be a significantly cheaper way to go given the price of OE pistons. There are also a number of Elans out there that have been intentionally sleeved on all four cylinders.

[PECKHS]

@ Enright, i saw your post too. it was before bob's, but then it just disappeared. i still remember what you wrote, at least kinda of.. tks anyway

wierd that when i spoke to my friend last night (he was not in when i went to the workshop), he told me the pistons can still be used. there is no apparent damage to the pistons, except that the bore has somehow gotten larger. i do not understand how that can have happened.

one thing for sure is that the previous owner has indeed swopped the engine, as the enigne number has clearly been tampered with to conform to the regulations here. i'm suspecting he has bought an engine that has been sitting around for a long period of time.

we used to sleeve the bore to get it back to size for some of our cars. the important point is the material used and the machine shop has to be very good as the tolerance for mistake is very minute. it has been done before, but not to 3 or 4 at one go..

i have not yet seen the pistons. will try to go to the machine shop and snap some pictures..

tks guys

[Specky]

Just thought, When you see the pistons have a look for a couple of things, a black coating on the top 1" (not the normal carbon fouling) and also examine the piston face for an "X" or an oversize marking.

TTFN

[bobbrown]

so how much bigger is the bore to the piston?
Is it barrel shaped or just too big top to bottom.?
Note you need to measure the piston on the skirt not above the top ring groove.
I suspect a miss match of pistons to bore.

[tigerdog]

This could have been causedif a 3 bar MAP sensor had been fitted without also changing the injectors and other components to compensate. As your Elanscan posted elsewhere shows signs of this being the case, please check this out before restarting your rebuilt engine.

[Dico]

With regard to Neils missing post- It happened with monty100 in the Elans for sale section. Hence all the confusion there, and only Clemo understanding any of it. It all seems to have corrected itself now.

[PECKHS]

Went to the machine shop earlier. Everything looks fine. The piston looks in good condition, and the bore is cylindrical as it should be. However, the bore is a little wide for the pistons, causing the oil to leak. I will post some pics I took when I reach home.
And, 1 of the piston(the 4th) is newer compared to the other 3.

[PECKHS]

This could have been causedif a 3 bar MAP sensor had been fitted without also changing the injectors and other components to compensate. As your Elanscan posted elsewhere shows signs of this being the case, please check this out before restarting your rebuilt engine.

I have got myself a new MAP, so I guess I should be safe, or at least i hope. On top of that, I've got myself new gaskets all around, new oil pump, new HES, new bearings for the crank shaft(??), new oil pressure sensor, new water pump and so other which I can't recall...

[racerstev]

So it's been apart before, figures. But to lose as much oil as you say I would guess it was something else.
I've seen oil rings installed wrong, it's easy to overlap the seperater rather then butt them like you
should. I've seen this 2 times, they smoke like crazy..

Steve

[PECKHS]

ok, pics of the pistons

piston 1
http://i132.photobucket.com/albums/q20/ ... G_2291.jpg

http://i132.photobucket.com/albums/q20/ ... G_2292.jpg

piston 2
http://i132.photobucket.com/albums/q20/ ... G_2293.jpg

http://i132.photobucket.com/albums/q20/ ... G_2294.jpg

piston 3
http://i132.photobucket.com/albums/q20/ ... G_2295.jpg

http://i132.photobucket.com/albums/q20/ ... G_2296.jpg

piston 4 - note that it is a newer piston of another make
http://i132.photobucket.com/albums/q20/ ... G_2297.jpg

http://i132.photobucket.com/albums/q20/ ... G_2299.jpg

the block, seems to be fine
http://i132.photobucket.com/albums/q20/ ... G_2302.jpg

bore #1
http://i132.photobucket.com/albums/q20/ ... G_2305.jpg

bore #2
http://i132.photobucket.com/albums/q20/ ... G_2306.jpg

bore #3
http://i132.photobucket.com/albums/q20/ ... G_2307.jpg

and bore #4
http://i132.photobucket.com/albums/q20/ ... G_2308.jpg

and this is a sample sleeve to reduce the bore size
http://i132.photobucket.com/albums/q20/ ... G_2300.jpg

gotta change the connecting rod bearing too
http://i132.photobucket.com/albums/q20/ ... G_2289.jpg

bad news is that SJ sports has just informed me that the standard sized piston rings are no longer available. he is suggesting to go for oversized piston and rings...but he haven't got them in stock too.

so i was looking at rockautos piston rings for the 91 impulse rs turbo.. i just cannot confirm that the standard ones ( ROCK PRODUCTS Part # PR326 ) are 80mm. any clues anyone???

i also need the oil pump and the TPS, whihc is also not available at either shops. anyone know a similar item? is it common to any other cars?"

edit - rockautos has replied ""Thanks for your email and interest in RockAuto - these parts are direct OE replacement parts, so, they will be the same as your originals (at standard sizing). Also, we currently have 18 of these available in the standard size."" so am i safe??

[PECKHS]

alternatively, my last option would be to get a replacement engine

this, if it's still for sale and if seller is willing to send to singapore

viewtopic.php?f=3&t=18083

or this, if it is the correct one...

http://cgi.ebay.com/ebaymotors/4XE1W-TU ... ccessories

he is willing to send to me

what do you guys think?

[bobbrown]

None of that looks to bad! when you said the bore was too big were you looking at the top of the piston or the skirt as the diameter above the top ring groove will be smaller then the skirt. easy way to tell is to place a piston in the bore and see if you have the 0.002" to 0.003" clearance. Note that the top of the bore will not be worn but then again there does not seem to be very much wear.
If the clearance on the piston skirt is correct then the reason for the smoke could be down to the bores not having been "glaze busted" when the repair work was carried out assuming they fited new rings as there is no sign of hone marks in the bore.


The engine on ebay For a bag of sand (£1000.00) + shipping is not that bad a buy and it should be the same.

From the look of it you get more than just the engine, OK the gearbox is not a lot of use for an Elan as it the 4x4 box but from the look of it you get the following Turbo, ECU, power steering pump, alternator and starter so they add up to quite a bit on their own.
Just did some quick calculations on the cost to ship to Singapore and assuming the whole lot weighs 500kg and packs into a box 1.5m square the cost is around $400.00.

a risk and you have to weigh up the pros and cons.

Bob