factory

Hi Zak
 
You could start a new thread, or add to a relevant existing one and we can help with any other questions you may have.
The Compact engines were of course designed as a small industrial engine to be used for powering all sorts of portable tools, but were also used for powering (and still are) models.
 
David

You may be best using clean fuel then, as I've never tried carb cleaner I don't know what it can damage (certainly some electronic & switch cleaner sprays can damage plastics or cause other problems with vintage electronics).
 
Be careful the power output shaft doesn't slide out & let the tiny bearing rollers fall out, if you take the induction housing apart and nothing is attached to it.
 
The only adjustment for the timing is the contact breaker gap (should be listed on the starter decal along with the spark plug gap). The flywheel position is fixed with a key.
 
David

If the exhaust collector will not move, the cylinder will need to be unscrewed. But make sure the piston is free to move before trying this, as the con-rod will break if the piston is stuck.
 
The engine maintenance manual gives details on making a cylinder removal tool.
The instructions given are to make it from a piece of flat steel 3/16" thick & 1" square, with a hole drilled in the middle for using a screwdriver as a "T" handle.
 
I made one from a piece of steel & bar found in a box of offcuts & salvaged bits in the shed. I didn't bother to make it 1" square though, I only squared up the ends and drilled the hole for the bar.
If the cylinder is very tight I usually use a vice to hold the engine crankcase (use wood or similar to protect the engine from the vice jaws) and use an adjustable spanner to turn the tool. You will probably need to replace the gaskets if you remove the cylinder to prevent leaks. Also make sure that the slot in the top of the cylinder lines up with the crankshaft or is at 90 degrees to the crankshaft when reassembling.
 
Here is a picture of the cylinder removal tool I made.
 
David

See the linked post for checking the carb inlet, there is a one-way ball valve inside the diaphragm chamber.
It's best to disassemble and clean all the parts of the carb using either clean fuel or carb cleaner.
 
The air vane fits inside the shaft of the butterfly valve (left side of carb), here is a picture I took earlier. The butterfly valve will be open normally, it closes when the blade part above the flywheel moves up with increasing air flow.
 

 
There shouldn't be any need to clean the crankcase with the cylinder removed unless there are bits of the old air filter inside (these would be visible inside the carb & induction housing), I would follow the engine rebuild thread if you have this problem, which is caused by running the engine without removing the old disintegrating foam.
There is a special tool that fits the slot in the top of the cylinder for unscrewing it, you will need to replace the exhaust collector gaskets if you need to remove the cylinder for de-carbonising, they tend to leak if you don't replace them.
See the last post in the engine rebuild thread for a details of the cylinder removal tool.
 
Taking pictures as you dissemble things will help when you put it back together, I always take more than I need to and not just with engines (vintage electronics is my other hobby).
 
David

Hi Zak,
 

Both the single and double air filter have one housing that doesn't come apart.
I usually use the little pick tool (shown in the linked post) or a small screwdriver to poke as much of the old filter foam out using all the holes in the housing. Compressed air can help with the remaining bits, I usually give it a wash with petrol/gas after.
The new foam is then squeezed in through the opening at the back and again poked through the holes at the front to spread it out to fill the housing.
 
 
Your carb will probably need to be stripped and cleaned following the procedure at the start of this thread, Old fuel/oil mix tends to gum up all the parts. Take your time, nothing should fly out, but have a tray underneath to catch any small parts if you want.
A new primer diaphragm gasket is usually required for the engine to run at it's best, the old ones usually dry out & crack (Wallfish or Webhead on here have new diaphragms, as well as the check valve gasket if you need them).
 
The screw with the spring of the left of the carb is the idle stop adjustment screw, the holes underneath are used on some tools for the throttle cable.
The small quadrant control on the other side of the carb is used to adjust the governed speed. There are two types of this control, one can be set to any position and the other is moved by lifting the spring loaded washer & has five positions. Early production carbs don't have this control.
 

 

 
David

I can't believe what my brother brought back from the local car boot sale this morning, an Orline (Edit: actually a CARBRA) hedge trimmer with an O&R model 20A engine!!
I don't think I've seen a model 20A engine on a hedge trimmer before and the it's first 20A I've seen in the UK (apart from on a chainsaw I have, but that was imported from the US).
 
It has been repainted at some point in the past, but the back of the engine housing still has the some of the original white paint on it though. The engine is a model 20A type 333, seems they riveted the model & serial number plates to the 20A engines instead of using the cylinder plate that gets lost on the later 13A/B engines.
 
David
 

I don't suppose you have a proper bottom cover for the blade eccentric/gearbox housing? It's currently got a very thin sheet of aluminium held on with cable ties at one end, as well as a lot of missing or incorrect screws. Also do you have any literature that shows this hedge trimmer at all? The engine dates to 1973.
I guess there must be a lot of unidentified model 20A engines out there, as it's hard for people to find out it's an O&R or AEP engine once the original stickers have gone.
 
David
 
edit
Apparently there are two different covers for the blade eccentric housing depending on the model, I've no idea what the difference is though. This infomation is from the parts list for the hedge trimmer with the 13A/B engine.

That's rather nice David, a lucky find then !!
 
So they are about...
 

I can't believe what my brother brought back from the local car boot sale this morning, an Orline (Edit: actually a CARBRA) hedge trimmer with an O&R model 20A engine!!
I don't think I've seen a model 20A engine on a hedge trimmer before and the it's first 20A I've seen in the UK (apart from on a chainsaw I have, but that was imported from the US).
 
It has been repainted at some point in the past, but the back of the engine housing still has the some of the original white paint on it though. The engine is a model 20A type 333, seems they riveted the model & serial number plates to the 20A engines instead of using the cylinder plate that gets lost on the later 13A/B engines.
 
David
 

Hi All,
David,
I got the mount machined up, still need some end plates made up(waiting on material), have trial fitted to the hull.
 
Cheers
Andrew

A few more scanned, the leaflets for the Turbair Tot 2S, Imp 12 & Scamp 240.
 

 
Turbair Leaflets, Tot 2S, Imp 12, Scamp 240.pdf
 
David

I've finally scanned the instruction manual for the Turbair Tot 2S and created a pdf of it.
 

 
Turbair Tot 2S Instruction Manual.pdf
 
There is more to follow when I've l got it scanned & edited.
 
David

A few more scanned, the leaflets for the Turbair Tot 2S, Imp 12 & Scamp 240.
 

 
Turbair Leaflets, Tot 2S, Imp 12, Scamp 240.pdf
 
David

I can probably get some measurements and some pictures of the Octura mount I have, if no one has one for sale.
 
They seems to be two versions of the Octura mount, mine is the standard cast alloy version, but I have also seen a version made from a section of extruded & machined aluminium.
 
Here are a couple of pictures of one (not mine);
 



 
David

It was the less common 350W version with the larger tank, one sold for a much more reasonable $250 in March, the more common model 300 Tiny Tiger are usually not too expensive.
 
David

I've finally scanned the instruction manual for the Turbair Tot 2S and created a pdf of it.
 

 
Turbair Tot 2S Instruction Manual.pdf
 
There is more to follow when I've l got it scanned & edited.
 
David

I've noticed that seller with the $500 Military Champ has been buying up & reselling O&R stuff, the Champ was bought two days earlier for $400, which is still $100 more than I've seen them sell for before. They also seem to be separating tanks & gearboxes from some engines and appear to have split up several Chicken Power kits.
 
I've been wondering if O&R's have been featured on one of those shed/garage clearance type TV programmes (where they often make up daft estimated selling prices on stuff you know isn't worth that much) as prices have indeed been getting very high recently.
 
Note that ebay is a bit dishonest with the prices that items with best offer sold for, they stopped showing the actual lower sold price a few years ago, but you can still find out the actual sold price by using the best offer history tool on goofbid, it only works with recently sold items though.
 
I was also surprised that the 350W Tiny Tiger made nearly $600 as it failed to sell the previous time at an auction start price of $300 with $400 buy-it-now!!!
 
David

Here is my O&R display at this years 1000 Engine Rally at Astle Park.
 

 
David

So that explains what the Turbair 21 is, if the seller had bothered to take a picture of the inside I would have probably bid too! Thanks for sharing it, I have quite a bit of Turbair stuff to scan & add to the forum when I have time.
 

 
It appears to have an earlier O&R engine so that may date it to before the other Turbair crop sprayers, it also looks a bit like the mystery Italian crop sprayer in the unknown thread but it's not exactly the same. I'm slightly puzzled as to why the pictures I posted of it have shrunk though, they weren't very big to start with.
 
David
 

Found one, here you go David

 

That's not a silly question at all, there were a few different types of imperial thread commonly used in the UK in the past, but the O&R engines use American UNC & UNF threads which weren't used much over here (apart from some computer parts & connectors, some of which still use them). UNC/UNF is also known as ANC/ANF but sellers often only use the number or fraction and the number of threads per inch e.g. #10 x 32tpi.
 
Below is a chart I use, created from several pages in an old reference book. All the threads apart from the spark-plug are either UNC or UNF, the spark-plug thread is metric.
 

 
The starter/blower housing & carb mounting screws are both #6 x 32tpi UNC, these screws have a Fillister head.
And the power output shaft (tapered version) is tapped #10 x 32tpi UNF, there is also a D shaped output shaft with no hole found on some engines.
 
David
 
Edit
 
Here is a PDF of the thread chart, as the picture above has been automatically reduced in size by the forum software making it harder to read.
UNC UNF Threads & Drill Sizes.pdf
 
David

That's not a silly question at all, there were a few different types of imperial thread commonly used in the UK in the past, but the O&R engines use American UNC & UNF threads which weren't used much over here (apart from some computer parts & connectors, some of which still use them). UNC/UNF is also known as ANC/ANF but sellers often only use the number or fraction and the number of threads per inch e.g. #10 x 32tpi.
 
Below is a chart I use, created from several pages in an old reference book. All the threads apart from the spark-plug are either UNC or UNF, the spark-plug thread is metric.
 

 
The starter/blower housing & carb mounting screws are both #6 x 32tpi UNC, these screws have a Fillister head.
And the power output shaft (tapered version) is tapped #10 x 32tpi UNF, there is also a D shaped output shaft with no hole found on some engines.
 
David
 
Edit
 
Here is a PDF of the thread chart, as the picture above has been automatically reduced in size by the forum software making it harder to read.
UNC UNF Threads & Drill Sizes.pdf
 
David

Phil Murrell, Wendy and I put on a small display at Hailsham Wyevale Garden Centre today
 
We were joined by one of the Garden Centre employees and his collection of petrol cans plus a couple of cars, a rather nice Rover P6 and an equally smart early 90's BMW 3 Series.
 
Here's some photos...
 

I have purchased some aluminum stock from Home Depot that was the same thickness, cut a small piece and filed it to size. Not real easy
dealing with such a tiny piece but I have done it many times with success. You MUST be innovative and resourceful with these things.

Actually, the diaphragm is bad. The fuel is coming out the vent hole on the dry side of the diaphragm. I've got parts coming from webhead. Yahoo! I'll miss the excitement of running a spark prone engine with raw fuel everywhere. Really keeps the senses up. LOL