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Gearbox and Ignition problems - ThomasSwiss - 28-09-2017
Hi all,
I own an austin seven blown with cozette loader. I bought it two years ago.
I have two problems.
my 4-speed Gearbox is very noisy 1-3 speed the 4th is ok. What is the cause, it must be repaired quickly?
the second Problem ist the Ignition timing. What is the correct Timing? I drive a coilconversion and i think
the timing is wrong
The Engine only rotates a maximum of 4200 rpm.
can someone help me with information?
Thanks and Regards from Switzerland
Thomas
(excuse my English)
RE: Gearbox and Ignition problems - Martin Prior - 28-09-2017
If you have an early "crash"-type 4-speed gearbox, it will be quite noisy at higher speeds in 1st, 2nd and 3rd as the gears are straight-cut. A synchromesh 'box should be much quieter in lower gears and if yours is of this type you may have a problem.
RE: Gearbox and Ignition problems - Ian Williams - 28-09-2017
Sounds to me like you have a set of straight cut close ratio gears, these are commonly fitted to specials intended for racing or hillclimbing, Don Rawson used to make them but I do not know if they are still produced. They are quite noisy until you get into top and for spirited a road car I would prefer a Nippy or Super Accessory type CR set such as Andrew Bird now makes, being blown you can probably get away with wider ratios than a natural aspirated car.
RE: Gearbox and Ignition problems - Steve Berg - 29-09-2017
Hi Thomas
I also live in Switzerland (Fribourg) and I'd be glad to help in any way I can.
My Nippy has a modified 4-speed gearbox to raise the ratios to Nippy specifications (supposedly). It is also noisy on the first three speeds due to straight cut gears. But it's a noisy car anyway :-), I wear now ear protectors (Pamir) to drive it.
RE: Gearbox and Ignition problems - Ruairidh Dunford - 29-09-2017
To add weight to the comments already made, my Pearl has a Nippy c/r box and has a (purposeful) whine on 1st, 2nd and 3rd. I quite like it however.
RE: Gearbox and Ignition problems - Austin in the Shed - 29-09-2017
Any older/vintage/classic car will be much more noisy with little or no sound insulation compared to a "modern" car,especially gearbox.Many conversions use corrected tooth form gears to achieve the different ratio.
You say you have a coil conversion,Is it one using a bosch 009 type distributor?.If it hasn't been modified to reduce its advance and bob weight springs its likely to have too much advance and too early.
As we all know its hard to diagnose something like this via computer but it should rev to 6,000 or so subject how much boost the cozette gives and carb and ignition settings being right.The car should start easily and be very lively!
Are you sure the rev counter is reading correctly ?
RE: Gearbox and Ignition problems - BLUTO - 29-09-2017
Timing
Adjust the distributor to the highest/smoothest possible idle speed and back it off a touch. I use an inductive meter with a rev counter to check the speed.
RE: Gearbox and Ignition problems - ThomasSwiss - 30-09-2017
(29-09-2017, 12:27 PM)Steve Berg Wrote: Hi Thomas
I also live in Switzerland (Fribourg) and I'd be glad to help in any way I can.
My Nippy has a modified 4-speed gearbox to raise the ratios to Nippy specifications (supposedly). It is also noisy on the first three speeds due to straight cut gears. But it's a noisy car anyway :-), I wear now ear protectors (Pamir) to drive it.
Hello Steve Berg
do you know an Austin Specialist in Switzerland?
I live near Schaffhausen and I wear ear protectors to.
Regards Thomas
(28-09-2017, 08:21 PM)Ian Williams Wrote: Sounds to me like you have a set of straight cut close ratio gears, these are commonly fitted to specials intended for racing or hillclimbing, Don Rawson used to make them but I do not know if they are still produced. They are quite noisy until you get into top and for spirited a road car I would prefer a Nippy or Super Accessory type CR set such as Andrew Bird now makes, being blown you can probably get away with wider ratios than a natural aspirated car.
Hi Ian
Thank you for the answers.
The seven was built by Don Ravson twenty years ago.
This will be the reason for the noisy transmission.
Regards Thomas
(29-09-2017, 01:20 PM)Austin in the Shed Wrote: Any older/vintage/classic car will be much more noisy with little or no sound insulation compared to a "modern" car,especially gearbox.Many conversions use corrected tooth form gears to achieve the different ratio.
You say you have a coil conversion,Is it one using a bosch 009 type distributor?.If it hasn't been modified to reduce its advance and bob weight springs its likely to have too much advance and too early.
As we all know its hard to diagnose something like this via computer but it should rev to 6,000 or so subject how much boost the cozette gives and carb and ignition settings being right.The car should start easily and be very lively!
Are you sure the rev counter is reading correctly ?
Hi
The car start easily and isn't very lively! the seven runs like a 20bhp seven
At 4200 rpm the Seven runs 60mph, I think the rev counter and speedometer is ok.
Regards Thomas
RE: Gearbox and Ignition problems - stuartu - 30-09-2017
Thomas, how is the Cozette driven? Your description of the performance sounds almost as if there is no drive to the supercharger. Is it driven by chain from a sprocket on the back of the flywheel, in which case I remember the car - probably!
Regards,
Stuart
RE: Gearbox and Ignition problems - Austin in the Shed - 30-09-2017
I wonder if your supercharger is giving any boost,There are some poor superchargers out there.Has your car always run this badly?
Do you have any photo's of the engine bay?
I've never tried this but if the blow off valve is accessable you could try taking it out and either hold your hand over the hole or a suitable plug and start the car,under throttle the supercharger pressure should want to blow your hand/or plug out if you dare to try it!
Unless you have a boost gauge that is.
Don Rawson knew how to build a good seven engine so originally it would have performed well.