Ouch!

[F690OTF(RIP)]

My brother is now a wanted Maestro-killer!

OK, that's not actually fair, there's no particular reason to blame him for the demise of our K-reg Clubman (A-Series). In any case, I'm determined that it's not a demise, merely an injury.

This is what #4 piston looks like:

http://boaz.org.uk/images/piston-head-web.jpg

At first sight, it looks melted. Closer inspection, and a quick look at the underside of the head show that what's happened is that the inlet valve has split on the stem, and the valve head has fallen into the combustion chamber and gradually punched a hole in the piston. It made a bit of a mess of the spark plug, too!

It made for a bit of an exciting day - Steve told me he'd broken down on the M40 near Oxford at about 10 o'clock. The AA man got him off the motorway, but couldn't fix it by the roadside (unsurprisingly!), so left him in a layby on the A34. I left work at lunchtime and went and towed him back to Reading.... in a Fiesta! (That car is definitely earning its keep) So that was fun, if a little nerve-wracking!

Anyway, I was just wondering if anyone has any ideas about how much it'd cost to put right, and where the best places to get parts from might be. The main things which are required are obviously piston and inlet valve. Would we need new piston rings? What are the practicalities of getting the head seen to (the inlet valve seat needs a re-grind at the very least) - does it need stripping completely?
Main question - can the piston be replaced without removing the crankshaft?
Any thoughts gratefully received.

[E_T_V]

It will probably be easiest and cheapest to find a lower milage 1.3 engine and fit that rather than repair the damage (new piston valve, rings and possibly a rebore and new valve seat insert too).

[F690OTF(RIP)]

The bore still seems to be perfectly OK.

Do I take it from your suggestion that a lower mileage (not hard at nearly 114,000) engine transplant would be easier that there's quite a lot of hassle involved in repairing it with the engine in the car?

[Austin-Rover]

Dan has a point, it's going to be a lot easier for you to simply repace the engine than repair what you have. Think of it as an opportunity to give the car a new lease of life too, a nice low miles unit will see it right for years to come!

[Jack]

I agree with E_T_V on this one. If there is that much damage to the top of the piston, I can't believe the bore is untouched.

Having said that, I think THEORETICALLY you may be able to get away with just changing the piston and valve. But you may do all that work and end up with an engine which is not 100% AOK.

You should (I think) be able to remove the big end cap and bash the piston up out of the bore from underneath. That will give a good idea of the state of the bore. Then you could just change the piston, checking clearances etc. first to make sure it'll be okay. I think you ought to change the rings but they probably only come in sets for all four pistons and when running cars on a shoestring...

Post a photo of the chamber in the head and we can all have a laugh / give our considered opinion.

Given the fact that you already have the head off, if it was my car, I think I'd have a go at replacing the piston and valve and see what happens. If it doesn't quite work you could always then buy another engine - I bet there will be some 1380cc modified mini ones on eBay somewhere that would tempt me! Good luck!

[MaestroMatt]

Brand new 1.3 engines are only about £100, aren't they? Get it changed!

[F690OTF(RIP)]

Chamber in the head looks like this:

http://boaz.org.uk/images/cylinder-head-web.jpg

It may be that the exhaust valve ought to be replaced or reground as well, as there's a little damage to its surface. Most of the odd texture appears to be sparkly deposit rather than damge to the head, but I haven't had a really close clean-up and look.

The engine turns OK, so we've had the offending piston at BDC and have looked at the bore pretty carefully. Honestly, it looks fine.

[E_T_V]

The valve seat area looks fecked to me try whipping out the valve next to it to compare them, and there is a good chance it'll need a new one, and a new piston and the valve of course. I'm afraid I don't think there are any £100 new engines lying about anymore I think they've all gone, however a good one from a scrap yard will cost you half that and will take a few hours to fit rather than the hours of labour you'll need to put the damage right.

[F690OTF(RIP)]

The photo's not very good, partly because of the flare from the flash. The inlet valve seat is nice and smooth except for one nick, so I don't think the damage to the head is that extensive.

I should point out that I'm not looking into this to extend the life of the car indefinitely - my brother's not that bothered about keeping it (although if I can fix it I might change his mind) and I don't have anywhere to put it. BUT it's all good fun and educational, so I'm not concerned about number of hours labour.

[E_T_V]

Ok bung a new piston in and a new valve (or even one from a scrap engine) and then put it all back together. It'll work but won't be quite as good as before.

Keep an eye out for someone breaking a 1.3 then see if you can get the engine from it to replace it. Either way the choice is yours :D

[ben rawlings]

Ok bung a new piston in and a new valve (or even one from a scrap engine) and then put it all back together. It'll work but won't be quite as good as before.

Keep an eye out for someone breaking a 1.3 then see if you can get the engine from it to replace it. Either way the choice is yours :D







or....give bro your fiesta and drop a new engine in the maestro and u can go back to driving one :cool:


ummmm...t16 clubman :)

[Jack]

I'd get a wire brush in a drill and clean up the cylinder head chamber to get a good look at it's condition.

What about replacing the head with this:

http://cgi.ebay.co.uk/A-series-race-tuned-cylinder-head-11stud-mini-MG_W0QQitemZ8010288948QQcategoryZ72205QQssPageName ZWDVWQQrdZ1QQcmdZViewItem

or this:

http://cgi.ebay.co.uk/Longman-race-cylinder-head-A-series-mini-midget-sprite_W0QQitemZ8011648317QQcategoryZ72205QQssPage NameZWDVWQQrdZ1QQcmdZViewItem

or whack this on a turbo head for some fun!:

http://cgi.ebay.co.uk/MG-metro-Turbo-turbocharger-and-manifold_W0QQitemZ4585948350QQcategoryZ27380QQrdZ1 QQcmdZViewItem

YOU KNOW YOU WANT TO!! ;)

[talyllynman]

Peter,
Since the car is, I believe, afflicted with a catalyst, obviously the ideal way from here is to find a low mileage "Catalyst" engine, preferably still attached to a 5 speed gearbox, with linkage, and to fit the lot. The 5 speed is usefull in two ways, it will improve the car, and the engine will have had a less frenetic life. Accepting that this is unlikely your options would seem to be.

Next best - find an "unleaded" engine and swap the fuel (and ignition?) system(s) from the old to the new and drop the whole lump in. This assumes that the difference between a "catalyst" engine and the plain "unleaded" ones is limited to the bolt on bits.

Next best - Rebuild as much of the old engine as necessary. Assuming the bore is OK (and it probably is as the loose valve head may have only given it only glancing blows) the practicalities/economics of this depend on the state of the head. If the damage to the inlet valve seat is slight enough you can just grind in a new valve then great, but if it needs recutting it may be more of a problem. I know the exhaust valve seats are induction hardened, but are the inlets?? If they are, recutting may be difficult. The exhaust valve has had a hard time, so I suggest changing that as well, 'cos the slightest leak here will soon get worse. A new piston ought to come with rings anyway. I don't know how the gudgeon pin is held in on one of these. If it is a push fit in the rod then it may not be a DIY job do refit the rod to the new piston.

Good luck, I look forward to seeing back on the road.

[E_T_V]

I believe the only differences in the cat and non cat unleaded engines are the vacuum system and the thermostat housing and also the charcoal canister if fitted. All the rest should be the same I think. Obviously the unleaded engines will have hardened valve seats in them and the timing settings are different for them but otherwise I think they are mechanically identical.

Also I had an interesting thought. I have been led to believe that the oldest component (engine or car) is what the MOT emissions tests are based on. In theory this would mean if you fitted an unleaded non cat engine (pre 91) then the emissions test would be based on that engine so would only be the 3.5%CO 1200ppm HC's, and so you could ditch the cat if you wanted.

[G Force]

Peter I honestly think you need to forget about repairing this engine it will cost more than you think to properly repair it.

The damage to the combustion chamber will not clean up enough to give reliable motoring in the future. It is actually the exhaust valve that is missing its head and the inlet valve is not salvagable. You have to also consider where all the debris has gone, it ends up in the oil and will have circulated itself back around the engine, almost certainly damaging the oil pump and crankshaft and other areas will be affected to a lesser degree. Even if you fit a new head pistons and crank etc. any debree that does not get cleaned out will come back to haunt you, it only takes a small amount to undo all your best efforts.

Best regards Gary :)

[talyllynman]

G Force,
I think your prognosis may be a bit bleak. I certainly agree that the oil and filter will need changing, and whilst the sump is off the gauze will need cleaning, but the pickup gauze and the oil filter should prevent the little bits going too far. If it is possible (I don't know where the oil pump is on these things) and time permits cleaning out the oil pump may be advantageous because it comes before the filter. Don't forget most of the bits in there are soft (comparitively) aluminium.

[G Force]

G Force,
I think your prognosis may be a bit bleak. I certainly agree that the oil and filter will need changing, and whilst the sump is off the gauze will need cleaning, but the pickup gauze and the oil filter should prevent the little bits going too far. If it is possible (I don't know where the oil pump is on these things) and time permits cleaning out the oil pump may be advantageous because it comes before the filter. Don't forget most of the bits in there are soft (comparitively) aluminium.

Sorry Talyllynman if you think the filter will cope with that amount of damage I am willing to put my money on you being incorrect. It is the smallest debree that gets through and wrecks engines, & not to mention the pummelling no4 big end got when the valve head came off.

But every one is entitled to an opinion of course

Cheers G

[F690OTF(RIP)]

It is actually the exhaust valve that is missing its head

I was wondering who'd spot that first... Oops! :o

[F690OTF(RIP)]

Well, the work on the head is finished. I don't have the photos with me at work, but it's not looking bad. The combustion chamber is admittedly not as smooth as it should be, but it's cleaned up OK. I've ground the new valves in pretty thoroughly and, having replaced all the valve stem oil seals while I had things apart, I'd say those seats are now in the best condition of all of them.

I've also got a nice new piston (at a price, I must admit - the valves were about a fiver each +VAT, but the piston was £40 +VAT!) on the rod, so all that remains is to take the bits back to Reading and re-unite them with the rest of the car.

Even if it doesn't work, I've had great fun doing it and hopefully it's all useful experience for the future.

[MaestroTurbo]

I've also got a nice new piston (at a price, I must admit - the valves were about a fiver each +VAT, but the piston was £40 +VAT!)



£40 quid is not expensive for a piston!

[awol]

I remember when i had a big-end bolt undo itself in my old G reg 1.3 maestro special (RIP G160MRM) i ended up getting a "low mileage" 1.3 a series engine from a scrapyard and fitting it, as i thought that would be the easiest solution. I had great difficulty getting the engine to run properly, but subsequently having stripped the old engine, i discovered it wasn't as bad as i thought, and i wish i'd attempted to get a new head gasket set, con-rod, big end bolt, and big end cap, and big end bearings, as i'm fairly sure it would have perfectly fixed it.

Good luck with your repair!

[PUDDSTRO TURBO]

Peter I wish I had seen this thread sooner Im in bevois valley (the bottom of your road) and have a whole unleaded engine and box 5speed from a k plate 1.3 lx, done 47k and spot on!, i drove it back from london!, its still sat in the car in my lock up by bedford place :fim:

It really is spot on if you want the whole lot give me a bell and £40.00 and its yours it will just bolt in and bingo your off again!

Infact ive got tonnes of stuff should you need anything else

Bell me on 07834 288280 Pudds :thumbup:

[F690OTF(RIP)]

I thought maybe an update on this saga was somewhat overdue.

We put the engine back together in late November and, after half an hour or so trying different combinations of plug lead connections (the moral of the story being to mark them when you take them off!), it started. Unsurprisingly, it ran a little rough for a while, but there was still that sweet and familiar A-Series sound :)

Last weekend it completed its 500 mile running-in period and it's running as well (and as economically, at 35mpg) as I remember it ever doing (although I haven't driven it very much in the past few years).

Now I'm just trying to clean up a few bits and pieces. If anyone fancies a World's Rustiest Tailgate competition, I'll be glad to post some photos up!

[ChrisM]

If anyone fancies a World's Rustiest Tailgate competition, I'll be glad to post some photos up!
I'm sure I can find a pic in my collection to enter... :hide:

Glad you've finally got your car back on the road :D