Renault 6TL "Crapaud"

[Honey Badger]

Wont cola corrode the bores if it's left in there?

[Taff]

Wont cola corrode the bores if it's left in there?

 

I got told that there is a lot of water in cola, not the sort of stuff you want inside a cylinder

[MikeKnight]

I was going to cola the bores today, but I think I'll hold off until I get some confirmation on this.

 

Never used the technique before myself. I was told to do it by the guy who works a few doors down, he's one of those "works on every car ever made" types and always seems to know what he's talking about though.

[Taff]

Like I said earlier mate, I used red diesel to unstick my engine and it worked a treat. I only used red because that's what was there.

 

Any old, thin-ish oil will help the unsticking process. If you have old brake fluid about, used that. Even cooking oil will help.

 

I brimmed my cylinders, put the plugs back in and then poured more oil into the bores via the valve gear. Basically, if it ought to be turning, pour oil over it. Then very gentle pressure on the crankshaft to try to "rock" it into turning. Mine took 3 months to free up. It then took another 7 hours to get one 360 degree revolution with no tight spots. The following day that engine fired up and it runs beautifully, no rebuild or anything. 

[sierraman]

I sit here concerned as I drink a can of Cola... If I leave it overnight will it unseize my bowels?

[vulgalour]

Been a while but today got some time in on this little green disaster zone.  At present the car is all bundled up like a festive gift in a lovely blue tarpaulin to keep it safe and dry and efforts so far to un-seize the engine have been utterly in vain.  So it was determined that today we'd see if it was the pistons, camshaft or crankshaft that was seized or a combination of all three.

 

Ordinarily for a first-time job like this I'd take a photo-diary of what was done but with the components being rather slimy-oily, using a camera wasn't a particularly good idea.  Suffice to say the whole job was relatively easy, the only slightly more involved part being removing the woodruff key from the washer on the camshaft and then not losing the woodruff key.  Everything was carefully wiped free of oily gunge with the exception of camshaft and crankshaft which I don't want to flash-rust as I'm not sure how long it'll be before I put this all together again.  The other thing to be sure of is that everything was put away in order, with labels, so I don't lose anything, particularly vital for this sort of job.

 

With the block upside-down it was easy to unfasten the pistons first, this did drop the liners out of the block which I'm told isn't ideal but also that it's not the end of the world.  I was expecting the liners to have some resistance to coming out but they didn't, they were really easy to remove.  The pistons are really firmly stuck too so they'll be getting a bath in hot engine oil as a last ditch attempt to free them, there was no way these were coming out in situ.

 

The rest of the internals were carefully removed and set aside, all the various bolts that go in the block were put back in their respective holes so I don't lose them and things like the pushrods and head bolts were stored in some labelled cardboard for the same reason.

 

With the block now free of everything I could see quite a lot of orange gunge in the water jacket which can't have helped with historic issues this little engine has had.  It also means getting a new radiator or refurbishing my existing one is a must, if this is what's in the engine there's going to be more of it throughout the coolant system and that all needs cleaning out.

 

The block and sump were pressure washed to get the worst of the gunk out, they'll get a deeper clean before the rebuild.

 

 

 

The good thing is that most items inside the engine are in good order.  The piston bearing shells look re-usable and if the liners and pistons can be persuaded to part company there's a chance they will just need a clean/hone and new piston rings before going back in the car.  The paper gasket under the liners will need replacing.  Crankshaft and camshaft are both good too, neither showing obvious signs of scoring or excessive wear.

 

The one item that showed wear were the main bearings, some of which are badly scored, so I'll need a full set of those.

 

I'll get some snaps of the other bits and pieces that were done at a later date.  The oil pick up/strainer is now lovely and clean after being de-gunged and the sump looks to be in pretty good order and just needs an exterior repaint.  Overall I'm quite happy with this.  Parts for the engine appear to be quite cheap and with it being so small and easy to work on it shouldn't cost much in time or money to get it all back together and functional again.

 

I just need to find a new set of main bearing shells, paper gasket for under the liners, a set of piston rings and pay a company to check the shafts and hone/clean the liners if we can get the pistons out of them and get the block properly cleaned before rebuilding it all.  I'll also need a new head gasket, I put the cart before the horse and rebuilt and refitted the head not long after getting the car back from Wales without un-seizing the pistons, silly me.

[Mr_Bo11ox]

Yo vulg!!! Nice work. I have one of these honing gizmos that go in an electric drill, the three-legged thing with a stone on each leg, you know what I mean. Anyway if you want to borrow it LMK and I'll bosh it in a jiffy bag and post it, and you can have a crack at the liners yourself!

[vulgalour]

ooh, I've seen those whizzy stone things before and they look top drawer.  Totally reliant on me getting these pistons unstuck, they're properly jammed in there so I'll give you a shout if/when I pop them out of the liners.

[Parky]

I wouldn't be surprised if an older Renault dealer had all that stuff on the shelf. Might be worth trying South Hill Garage in Laindon, Essex. They are an independent Renault specialist now but were a Proper dealership for donkeys years beforehand. They probably have them sitting in a dusty box in a corner somewhere.

 

As has been mentioned elsewhere these engines crop up in lots of other Renaults so many engineering shops should be able to help you out without too much trouble. Gosnays in Romford is another good one and if they won't send stuff out I can happily collect for you and dispatch that way

[jonathan_dyane]

Exciting progress

[CHRIS1980]

I'll just leave this here......

[dollywobbler]

Excellent. 

 

Specialist possibilities.

www.renospeed.co.uk

http://www.renaultspeed.co.uk/

 

I believe they are two separate companies with original* naming ideas.

[wuvvum]

What are you messing around with that lump of rust for?  What you want is one of them Dacia Denem engines.  Drop straight in, they do.

[junkyarddog]

Now that the pistons and liners are out of the engine,

would it be an idea to take one home and pop it in the oven,

get it good and hot,remove then whack the conrod with a mallet?

 

Might shift them.

[Lacquer Peel]

What are you messing around with that lump of rust for?  What you want is one of them Dacia Denem engines.  Drop straight in, they do.

 

I keep thinking about an old longitudinal FWD Renault with the 2.1TD out of an Espace.

[CHRIS1980]

I keep thinking about an old longitudinal FWD Renault with the 2.1TD out of an Espace.

Veg oil classic for the win.

[vulgalour]

Oven baking is not an option, there are many things I will put into my home oven but rusty oily bits of car are not one of them.

 

Tried putting the piston and liner combo in a pan of hot engine oil on the hob, it was hot enough that the oil was trying to climb out of the pan.  No joy at all, it just cleaned up the bit of piston you can see which, incidentally, looked pretty good.  No magic POP of freedom though, sadly.

 

I've been given two other suggestions:

 

1 - apply a lot of heat to the liner and douse the bores in penetrating oil to make use of the different rates of contraction and expansion between liner and piston.

 

2 - put it in a press and push the pistons out of the liners with sheer hydraulic force.

 

I don't like idea 2 so much, I reckon that stands a good chance of messing things up pretty spectacularly.  Idea 1 I don't hold much hope for either as so far heat and oil (of various types) haven't done anything bar cleaning visible surfaces.  Really though, I don't know what to do about this beyond possibly binning them and buying new ones.  Trouble is, con-rods seem harder to come by than the piston heads and I can't get to the gudgeon pins with the pistons locked in the liners where they currently are so that I can free the con-rods to use on new piston heads.

[Mr_Bo11ox]

You're never going to get a 'pop' after which they're free. Heating them up will expand them, hopefully at different rates, which will reduce the force needed to move the piston in the bore. But even if you heat them both to 800deg after a week soaked in oil, you'll still need to squeeze em in a vice or wallop them with a hammer or whatever to shift em.

[vulgalour]

I am expecting too much of physics and such, yet again.  Jobs like this should always go with a nice POP as far as I'm concerned and while I fully endorse the use of hammers at any opportunity, it would be nice just once not to have to resort to them.

[vulgalour]

Since I've been fiddling about with the engine tonight, here's some pictures I didn't provide last time.  First up the oil pick-up/pump/strainer thingy.  This was all gunged up and the spindle was not that free moving but after a soak in some cleaner and a bit of a scrub it's lovely and almost sparkly and the spindle moves much better now.

 

 

A sample section of the camshaft.  It's all like this.  There's no sign of excessive wear or scoring from what I could see so I'm hoping it needs little more than a good clean.  More experienced eyes may see issues I'm not aware of on this component.

 

The main bearing shells didn't look as bad as I remembered.  There are a few scores on a couple of the shells but not the mess I'm sure was there when I removed them.  Perhaps they just aren't as bad as I thought.  Can these be reused, do we think?

 

 

Finally tried a bit of home cooking.  Didn't achieve anything bar cleaning the surface of the piston head that's visible outside of the liner.  I won't be doing more of this at home even if it does help, I hadn't realised just how much of a stink it would make and the kitchen now has that satisfying odour of a well used garage, which isn't a smell I really want in the kitchen.

 

I'll keep plugging away, we'll get there eventually.

[vulgalour]

After yesterday being a bit of a no-go on the car front, today was much better.  I got out one of my favourite tools and used it in conjunction with a lump of wood and a big old bench vice.

 

It was surprisingly easy to free all four pistons from their liners and I'm delighted about that.

 

None of the piston rings were broken and the pistons themselves look in good order.  There's no obvious sign of steps, scores or other damage in the liner bores either which I'm delighted about.  The next step is definitely to get everything cleaned up and assessed properly to work out what I do and don't need to replace before rebuilding this little engine.  Feeling much more positive about it all.

[Dick Cheeseburger]

Startup video needed when it happens. Result.

[vulgalour]

I don't think I need to spend a lot of money on this engine, mechanical parts are surprisingly cheap, I did a bit of rough estimating and came up with the following:

Oil filter - £3 ish

Oil - £20 (I might even have some in, if so FREE)

piston rings - £30 ish

paper gasket for under the liners - £?

Head gasket - £8-15

Spark plugs - £8-12

Rotor arm - £3-5

Plug leads - £?

Air filter - £3-5

Coil - £8-15

Fan belt - £10

 

I can probably rebuild, fill with fluids and get it driving for under £200.  That's ridiculously cheap.

[cort1977]

Good news Mr. V.  

 

So you just put the liner in the vice and hit the piston with the BFH?

[vulgalour]

Almost exactly, the wooden baton made a good drift and prevented me damaging the piston face.  It was surprisingly easy so perhaps soaking it all in oil and diesel and whatever for so long probably helped.

[purplebargeken]

Whoohoo! That is all. 

[wuvvum]

Excellent.

[seth]

Good news on the pistons.  I'd not be so sure about re-using those main bearings though. The yellowy colour showing through the silver of the bearing material, particularly of the centre one means they're on their last legs.  If you can get a new set for not too much money I'd be rather tempted to get them.

[jonathan_dyane]

Good progress. I hope the liners clean up ok; hopefully Boll's honing device will do the business.

[vulgalour]

@Seth:  that yellow colour was mentioned on another forum with the same concern, it's actually a smear of oil rather than worn metal.  Everything I picked up that day (including the camera) got engine oil on it.  I'm trying to find someone I can buy all the parts from in one go so I'm not paying for three or four lots of postage and so everything arrives together.  The paper liner gaskets are proving very elusive and some of the parts I find listed for Renault 6 turn out to be for the early 850cc engine which are a different size and no good for me.