The place for technical discussions about GA and flying.
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By ikcarusflyer
#1807887
I realise this will be a controversial topic.. but in lack of a clubhouse discussion during lockdown, I thought I might broach the subject.

We're well aware of the benefits of modern engines such as the 912 and the power/ efficiency they can give in a small package. We're also aware that the C65 etc.. found in so many vintage beauties like the Champ is reaching a particular age, and parts are neither easy nor common.

Rotax in a vintage bird just doesn't sound right. There's something emotive about the 'put put' sound of a champ going past. But what about D-motor? Side valve, simple construction, similar horsepower and weight to a c65 with direct drive for similar revs. To me it looks like a d-motor conversion might rescue quite a few vintage birds.

What's your thoughts?
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By Bathman
#1807921
I agree. Every airfield I kick around at seems to have a significant number of aircraft grounded because of engine problems.

The killer is the cost I’ve heard of 20K plus bills for an overhaul on something as simple as an O-200 in a Jodel.

Second hand Rotax 912 can be picked up for a quarter of that and will still outlast a small conti
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By Trent772
#1807988
A Rotax in a Jodel has been done and it looked OK, however - there are some standards.... A Rotax in a Champ, steady on now :pale:

Dump the A-65 and slot in a C-85 and you are good for 20 years or so.
By ikcarusflyer
#1808074
Trent772 wrote:A Rotax in a Jodel has been done and it looked OK, however - there are some standards.... A Rotax in a Champ, steady on now :pale:

Dump the A-65 and slot in a C-85 and you are good for 20 years or so.


I would draw the line at a Rotax in a Jodel! But the D-Motor... low revving with a put-put sound. It could be a solution? I'm just curious really! But definitely re-engining some of these beautiful machines has to be a solution
By ikcarusflyer
#1808076
Rob L wrote:
ikcarusflyer wrote:...But what about D-motor? ...


What on earth is a D-motor?


It's a liquid cooled 4 cylinder/ 6 cylinder that is starting to enter into the UK. I think (and I might be wrong) it's of American origin. It's direct drive, so to me, seems most similar to a c65/c85 for use in a vintage machine where sound is so important!

https://www.g-tlac.com/d-motor/
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By Paul_Sengupta
FLYER Club Member  FLYER Club Member
#1808077
It's a side-valve lawnmower-y thing expanded out to a largish 4 cylinder engine!

It does make it quite compact. It's been around for some years now. It was going really quite cheap at one of the shows I went to some years ago (something like $6000? Looks like it's a lot more now).

It's from Belgium.

https://en.wikipedia.org/wiki/D-Motor_LF26

Of course they're not the only direct drive engines around.

https://ulpower.com/en/engines

My friend who built the Escapade had those two engines to choose from and eventually went with the UL 260.

UL Power is also from Belgium.
By romille
#1808079
Trent772 wrote:
Dump the A-65 and slot in a C-85 and you are good for 20 years or so.

Try finding a decent C-85 that doesn't need a pile of money spending on it, they are less common than hens teeth. Even engines that are just a core for reworking are expensive.
My main concern with modern engines are the electronics, which I agree makes them more reliable, but a total flipping nightmare when they go wrong.
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By Sooty25
#1808142
But how much time and money gets spent rebuilding magnetos and carbs?

As long as the modules don't go obsolete, I'd go electronic ignition every time if I could.
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By Kemble Pitts
#1808180
In principle, an aeroplane flying is better than one parked with a duff engine.

D-Motor, hmmm. One of them put me into a field twice in one day this Summer when it decided to drop to tick-over at 1500' AGL. Waggling the throttle had no effect.

It was a very hot day, and it did tick-over beautifully smoothly, but that wasn't really what I was after at that moment... :shock:
Being an un-certified engine means that the electronics/software/systems haven't had the necessary rigour applied and so 'issues' are more likely.

It also means that you couldn't put one into a certified aircraft (see above).
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By seanxair
FLYER Club Member  FLYER Club Member
#1808261
There was an article not long ago about Bill Brooks in one of the magazines, LAA possibly. He, if I remember correctly, rebuilt a Jodel and put a 912 in it. Very successful by all accounts.

Read something else recently about modernising MGBs which made sense. Decent engines and gearboxes, heaters etc. Better than freezing your nuts off while waiting for it to break down. :)
By romille
#1808279
Sooty25 wrote:But how much time and money gets spent rebuilding magnetos and carbs?

As long as the modules don't go obsolete, I'd go electronic ignition every time if I could.


As I said electronic ignition and fuel injection are fabulous until they decide to go wrong, then diagnosing the problem is an utter nightmare unless you have the correct equipment, software and explanation of the error codes. I have a modern car with lots of sensors, when it decides to illuminate one of the warning lights, I don't have a clue which sensor has gone wrong so it goes to the garage to be plugged in and have a stupidly expensive sensor replaced. My other car is an old Land Rover with no electronics and three sensors with matching dashboard lights, it never goes to the garage and the replacement sensors are cheaper than chips.
By A4 Pacific
#1808286
I have a modern car with lots of sensors, when it decides to illuminate one of the warning lights, I don't have a clue which sensor has gone wrong so it goes to the garage to be plugged in and have a stupidly expensive sensor replaced.

Code readers are available quite cheaply on eBay.
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By romille
#1808291
A4 Pacific wrote:
I have a modern car with lots of sensors, when it decides to illuminate one of the warning lights, I don't have a clue which sensor has gone wrong so it goes to the garage to be plugged in and have a stupidly expensive sensor replaced.

Code readers are available quite cheaply on eBay.

I bought one of those, plugged it into the OBD port and got absolutely nothing, so I took it to the garage where it was plugged into a snap on reader costing about £4.5k, and bingo it gave us the answer. I think the cheaper amateur sensors read only one format whereas the professional ones read EOBD. OBD. OBDII etc.