General My (original) timing belt after 130,000 KM

[bugsymike]

You can't really beat a good volume steam engine with large flywheel. Not much to go wrong! Also same goes with a two stroke engine.

The Wankel engine was in theory a high RPM valveless equivalent of a two stroke engine. Also very simple in design and moving parts. Sadly rotor tip wear was it's major problem.

Also side seals on the ones I worked on, gave symptoms like head gasket failure, water bubbling out of the radiator etc..
The rubber sealing rings between the housings used to get damaged by the heat in the area of the leading and trailing spark plugs. Mazda's solution was a tin shim in the groove nearest to the heat source, trouble is on the few I rebuilt in the late 1970s the customers were loathe to hang on to them afterwards long enough to see if it was a permanent cure or not.
The rotor tip "chatter" and wear could be reduced if the vehicle was serviced at the dealership as we had a strict test and calibrate system for monitoring the oil flow from the little pump into the inlet, so many ml's in some much time measured into a burette.
Strangely for a high revving engine the limiter was set to 7500rpm I recall, fuel economy was poor with the four barrel carb, I never saw figures for the injected versions as left in 1982 to go self employed. Although one ex lady customer of the dealership used to travel a 100 mile round trip for me to service her RX3.

 

[Pugglt Auld Jock]

Also side seals on the ones I worked on, gave symptoms like head gasket failure, water bubbling out of the radiator etc..
The rubber sealing rings between the housings used to get damaged by the heat in the area of the leading and trailing spark plugs. Mazda's solution was a tin shim in the groove nearest to the heat source, trouble is on the few I rebuilt in the late 1970s the customers were loathe to hang on to them afterwards long enough to see if it was a permanent cure or not.
The rotor tip "chatter" and wear could be reduced if the vehicle was serviced at the dealership as we had a strict test and calibrate system for monitoring the oil flow from the little pump into the inlet, so many ml's in some much time measured into a burette.
Strangely for a high revving engine the limiter was set to 7500rpm I recall, fuel economy was poor with the four barrel carb, I never saw figures for the injected versions as left in 1982 to go self employed. Although one ex lady customer of the dealership used to travel a 100 mile round trip for me to service her RX3.

Always thought the RX3 was a bonny looking car

 

[bugsymike]

Always thought the RX3 was a bonny looking car

I agree 100% Jock, they and the conventional engine 818 version were a smart looking little coupe and even the 1.3 and 1.6 manual or automatic were good to drive.

 

[Pugglt Auld Jock]

I agree 100% Jock, they and the conventional engine 818 version were a smart looking little coupe and even the 1.3 and 1.6 manual or automatic were good to drive.

I've mentioned this before but it was some time ago so, just in case you missed it, back in the early '70s when I was really getting my feet under the table at Firestone (I'd been there about 3 years by then) we had a small, cash strapped, private entry team of two Mazda RX3 cars. They were very interesting to work with real enthusiast/semi professional motor engineers. The cars were decently quick too but the one thing everybody was talking about was how noisy they were. I remember they were always experimenting with exhausts too, much like 2 stroke tuners do. I'm trying to remember where it was, I think probably the Saltzburgring in Austria where the track runs along the side of the hill over behind the pits in a long straight, Even with a 6 cylinder BMW howling past on the pit straight just yards from where I would be standing, you could hear these wee Mazdas screaming along that straight a good half mile or so away! Only car that made more noise was the V12 Matra which had a particularly violent and piercing high pitched exhaust note. I remember the way it "tickled" deep down in your ear as it went screaming past - all "open pipes" in those days:



Probably one of the cars which contributed most to my later life tinnitus! Try we I did, we never got them onto our tyres! Compared to the V12 512 Ferrari at that time, which did run our tyres, which also made a glorious noise but was nothing like as penetrating. It made a gloriously guttural roar and it had an especially "delicious" overrun noise when the driver lifted off the throttle:



That car's actually a long tail whereas it was the "M" version I mostly encountered, but it gives you a good idea of the sound. I always thought the 917 Porsche didn't sound anything like as good, but by golly could it go!

Back to the Mazdas though. Either put your head phones on or play back through a decent speaker system and watch/listen to this. Space framed Mazda RX3. It goes like stink and sounds divine. Careful with the volume though, I like it really loud though!



Seems to be quite a big cohort of rotary engine followers down under. Here's a rip snorting RX3 being used for drag racing:



Obviously producing rather insane amounts of power.

There are other interesting videos of Australians building multi cylinder - do you call them multi cylinder? - Wankel engines which are well worth a look

 

[Pugglt Auld Jock]

PS to the above about the Mazdas. Do you notice, at about 3 minutes into the video, the only car which really gives him a run for his money is a Sunbeam Tiger! I'd love to know what they'd done to the engine in that. Unsurprisingly it can't stay with him on the "twisty bits"

PPS. You have to watch the drag car right to the end. His first two runs he gets altogether too "squirrely" and backs out before the finish line. the third run is pretty good, no damned good, but the fourth is best. Look at the timing board on the left, top numbers are what time he's doing it in and bottom is terminal speed as he breaks the beam.

 

[bugsymike]

PS to the above about the Mazdas. Do you notice, at about 3 minutes into the video, the only car which really gives him a run for his money is a Sunbeam Tiger! I'd love to know what they'd done to the engine in that. Unsurprisingly it can't stay with him on the "twisty bits"

PPS. You have to watch the drag car right to the end. His first two runs he gets altogether too "squirrely" and backs out before the finish line. the third run is pretty good, no damned good, but the fourth is best. Look at the timing board on the left, top numbers are what time he's doing it in and bottom is terminal speed as he breaks the beam.

Yes I saw the Tiger V8 disappearing on the the straights.
Everything else seemed to be a moving traffic jam, I only heard him on the rev limiter once I think
The final drag race really hooked up