Microlighters

Most definitely... That is by far the best engine available for this plane! If I had the dosh I would be using one myself.

Finally got it home. And now I must get my *rse in gear and get her flying!

Had a minor technical hitch though. The wing stub is 20mm wider than the garage door. And no amount of twisting and turning would get it through!

So for now it is sleeping under the afdak, while I get some quotes on replacing the two single doors with a double.

I think the only real problem with Carl's design over the original Zodiac is the added width of the wheel base, and wing stub. Just that little added width means it fits in no standard trailer, and is marginal to fit through a standard garage door.

Justin

Well, got the engine off, and on the bench. Started stripping for inspection, and got a nasty shock...

A few compulsory ADs were not performed. As a result, there is some fairly significant damage in the accessory case. The engine was 1 bolt (the other 3 had already sheared) away from a mechanical failure. Would have destroyed the alternator and secondary ignition. The imbalance on the crank would have probably done a lot more damage.

Fortunately I caught it early. Will have to test the various magnets to make sure they are OK (they were rubbing, so probably overheated), and inspect the rest of the flywheel assembly. Hope there is not too much damage.

On a positive note, I was fixing my fridge, and accidentally discovered that 10mm pipe insulation, when split lengthwise, 'clips' perfectly over the door frame tubes, and forms a very good seal when the door is closed. R14 worth of insulation will do all my door seals.

Also managed to get hold of all the hardware for the seat belt mounts, so those will go in soon too.

Back to work!

Justin

Photos Justin, PHOTOS .

OK - here are some really cr@p camera phone photos. Impossible to see if the bloody thing focussed correctly until you load it on the computer, and then it is just too late!

Here is the trigger magnet assembly. Note the varying length bolts to the left. They all started out the same length - the rest is still in the flywheel. All but one had sheered completely. All the roll pins had also sheered. As a result, everything was a bit wobbly. As you can see on the trigger magnet to the right, it had been rubbing against the sensors.
The entire flywheel was also wobbling, and as a result the stator was also rubbing. You can see a nicely polished piece here:
The same for the primary ignition magnet and pickups.

I don't really know how to check how much damage was really done - I am sending off a post to aeroconversions now to ask...

And more bad news...

Pulled the heads, and got a beautiful view of what detonation does to a cylinder:
You can see the classic yellow deposits in the centre, as well as the melted, and eroded aluminium on the right. In the right-hand cylinder, the hone marks are still perfectly clear (although the piston crown is carbon coated - running waaayyy too rich).

The cylinder bore is heavily scratched. I get the distinct impression that this engine must have seized, or come very close to it. I can't believe the previous owner didn't realise he had trucked up the engine...

The cylinder head:
Head gasket melted, and burned away. And a nice trench burned into the head, on the side of the combustion chamber...

JôJôJô!! Ai man, that's not the thing one wants to see. But you have two excuses now; rebuild the engine and you know it's new or buy another brand..... .

Luckily the previous owner wasn't flying above the sea. Could have seized up completely and then something about a boat anchor accordingly to someone there in Moerlandspan .

At least your project will take you a little bit longer ( more time fiddling with the tools is always lekker ), but then you'll have to wait longer before you fly. Always something to give before you get something else.

Good luck, man.

Ag no man! Justin, my sympathies. Its for this precise reason that I would be hesitant to buy a 2ndhand engine - unless I can testdfly it first, or the price is really right .

I honestly hope you paid a substantially reduced price?

Having spoken to a number of people who successfully run VW derivative engines, I came to the conclusion that they are fine as long as you assemble them correctly (don’t send them to your friendly beetle dealer… ). I understand Aerovee supplies a DVD of how to assemble correctly and that the engine kit goes together in a few evenings? Perhaps it will be helpful for you to get a copy thereof? (Speak to OFH – he might have such a DVD, since he has an Aerovee as well)

On the bright side though - You will be very familiar with your engine once you have repaired it - something that I believe is critical to firstly having confidence that it has been assembled correctly and secondly giving you intimate knowledge of its workings.

Good luck!!

PS remember you might have a claim against the previous owner, if you can prove that he knew about the problems with the engine at the time of selling it to you. This is the case even if it was sold 'voetstoots'. Its referred to as 'misrepresentation on/of a presentation'. Problem is that your legal fees will probably be much more than the actual claim. Check it out though - perhaps you can recover some of your costs through the small claims court?

It angers me that people will be so dishonest

Yeah. I reallise that I am waayyy too trusting to be in this business. This is the second time I have bought a dud from supposedly reliable people (or people with good references).

I don't think this was the engine builder's problem. The compression ratio checked out correctly as 8.0:1 - the engine was probably run on mogas and/or not maintained correctly.

I will get my AP out to give a second opinion. If he is also of the opinion that the owner must have known there was damage, then I will contact him. It is vaguely possible that he just did not know...

At 8:1 compression you will have to run really massive timing advance to cause detonation even on mogas. Somebody got the timing setup way wrong.

Stephan van Tonder wrote:At 8:1 compression you will have to run really massive timing advance to cause detonation even on mogas. Somebody got the timing setup way wrong.

Hmmm... The timing is pretty fixed. It can only change by a degree or two. It could have been bad fuel, or possibly a chicken-and-egg situation.

I just got an email on the AeroVee list, where someone had a similar problem. It started with a loose head stud, which allowed combusion gas to seep past the head gasket. which then melted. For some reason, it seems that once the head gasket is blown, you also get detonation (or at least the same results). No idea how, or why though.

Boat anchor.

Boet wrote:Boat anchor.

Nou hoekom het ek geweet dat hierdie pos kom...



EDIT: The fact that the engine still ran well, and had good compressions does speak well for the VW engine. It can take a beating, and still keep you in the air. But as for any engine - it MUST be maintained well if you want it to last.

On a side note, I finally finished installing the new garage doors this morning, and got the Raven safely stowed in her new home!

Some more cr@ppy cell phone shots: The Raven is 2420mm wide, and just does not fit through a standard garage door at 2400mm. Had to widen the opening, and fit the biggest standard doors I could find.

And more good news. Got word today that I have indeed got a hangar at Rhino, and even got someone to sub-let it until I am ready to move in! Many thanks to the Rhino guys!!!

Hi Justin,
Sorry to hear about your engine troubles.
How many hours has this engine done ?
What type of aircraft was it's original "home"
Carb or injected
Hows the bottom end looking ie case, crank, cam, follows etc
Regards
Glen