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Quickie(Q1) Onan Engine Spec's?

Rich Gillen
 




From: armilite@...
To: Q-LIST@...
Sent: 12/1/2018 4:28:14 AM Central Standard Time
Subject: Quickie(Q1) Onan Engine Spec's?


The Original Quickie(Q1) used an Onan Engine that was 18hp@3600rpm. Does anyone know what CC/CI it was and is that the right rpm that it was rated 18hp at on the Q1? I believe the Onan was upgraded later to 22hp by Milling the Head for a Higher CR, does anyone know what the Onan Spec's were? Did it use a Reduction Drive? They seem to have been used on Generators and Lawn Tractors at least.

Bore
Stroke
CC
CR
Carb Size
 ============================
Bore
Stroke
CC
CR
Carb Size

Does this look like the Spec's?


This manual shows 7.0cr for 18hp, 20hp, 24hp.


David J. Gall
 

Rich,

The 16 hp was 46 ci and the 18 hp was 48 ci. Onan called them the B46M and B48M, respectively. The Performer Series (P220, etc. that you listed below) were a later generation engine, potentially better but also larger and heavier. I think one experimenter was adapting the P220 but I never saw a full write up or successful test report.

On the B48M, QAC shaved the 18 hp heads and opened up the carb throat and claimed 22.5 hp. Onan designed a new head and rated it at 20 hp. All were direct drive flat head side valve horizontally opposed two cylinder engines, having two crank throws (that’s important for vibration and equal intervals between power pulses). All ratings at 3600 rpm (think 60Hz AC electricity generator engine).

QAC machined the cooling blower vanes off of the flywheel, removed half of the throttle butterfly shaft, and bypassed the built-in governor (but did not remove it).

QAC’s engine mounting scheme was poorly engineered and led to engine oil leakage and gradual failure of the intended vibration isolation, so after some hours in service, engine vibes went directly into the airframe.

I don’t know why you’re interested in this; the engine is obsolete and much better alternatives are available.

David J. Gall
Quickie kit number... oh, hell, it’s been 37 years and I forgot the damn number! ;)

PETER HARRIS
 

Hi David you still punching above your weight! Don't know if this belongs on Q Performance but I have fitted a Jabiru 3300cc engine rated 120HP and registered my Q2 as a Q200 in the Sport Aircraft category. I have fitted simple fuel injection from a single throttle body mapped in a Haltech system and recently fitted dual electronic ignition using HE pick ups and Tridon ignition modules. So far I get 170KTS CAS at 3000 ft. at 2800RPM using a Sterba 56X72 racing prop. There is more power to be gained as this engine has no intake plenum so induction is uneven also peak power is rated at 3000RPM so I am well below best output. There is always a better way.

Cheers

Peter

On 2/12/2018 10:07 am, 'David J. Gall' David@... [Q-Performance] wrote:
 

Rich,

The 16 hp was 46 ci and the 18 hp was 48 ci. Onan called them the B46M and B48M, respectively. The Performer Series (P220, etc. that you listed below) were a later generation engine, potentially better but also larger and heavier. I think one experimenter was adapting the P220 but I never saw a full write up or successful test report.

On the B48M, QAC shaved the 18 hp heads and opened up the carb throat and claimed 22.5 hp. Onan designed a new head and rated it at 20 hp. All were direct drive flat head side valve horizontally opposed two cylinder engines, having two crank throws (that’s important for vibration and equal intervals between power pulses). All ratings at 3600 rpm (think 60Hz AC electricity generator engine).

QAC machined the cooling blower vanes off of the flywheel, removed half of the throttle butterfly shaft, and bypassed the built-in governor (but did not remove it).

QAC’s engine mounting scheme was poorly engineered and led to engine oil leakage and gradual failure of the intended vibration isolation, so after some hours in service, engine vibes went directly into the airframe.

I don’t know why you’re interested in this; the engine is obsolete and much better alternatives are available.

David J. Gall
Quickie kit number... oh, hell, it’s been 37 years and I forgot the damn number! ;)