MCCULLOCH The official McCulloch thread

[heimannm]

I haven't seen one of Brian's sets in person so I can't comment on what he's doing but the OEM parts are thin spring steel as you have discovered.











Mark

 

[qurotro]

I haven't seen one of Brian's sets in person so I can't comment on what he's doing but the OEM parts are thin spring steel as you have discovered.

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Mark

Thanks for the reply and the pic! I think I’m missing a gasket under the rubber pump piece. I’m not the first one into this thing.

 

[qurotro]

After some observation of the pics, is there anything under the steel shim? All I have is the shim itself and it seem something is stapled with it.

 

[heimannm]

The OEM piece has a thin cork gasket stapled to it.



Mark

 

[cinci5]

The OEM piece has a thin cork gasket stapled to it.

View attachment 444497

Mark

Mark how thick is the spring steel part?

 

[hacskaroly]

The OEM piece has a thin cork gasket stapled to it.

I wonder who was the guy was who said..."let's just staple it" and another engineer said "hey that's a good idea".

 

[qurotro]

Mark how thick is the spring steel part?

Very thin. I believe it's sharp enough to cut your finger.

 

[cinci5]

After some observation of the pics, is there anything under the steel shim? All I have is the shim itself and it seem something is stapled with it.View attachment 444471

There shouldn't be a reason to replace the metal valve unless rusted.

 

[cinci5]

I wonder who was the guy was who said..."let's just staple it" and another engineer said "hey that's a good idea".

It was for the women who assembled them I assume.

 

[qurotro]

There shouldn't be a reason to replace the metal valve unless rusted.

I’m not intending to replace mine. But someone had mess with it before hence gasket is missing.

 

[Sloa]

When my saw was acting like that it ended up being an air leak. It wasn't pulling fuel because there was no pulse. The saw would even fire and run on prime.

Hello, may I ask how I would go about pressure testing. Do I seal at manifold in air box and exhaust. If this holds then check off and if not do I remove tank and repeat with bare intake . Next if fails I remove clutch and flywheel ( soap and water).
I will also get a supply of seats as Mark stated the swelling makes the Flat back unpredictable from day to day.
I do want to run with the flat back but am hedging my options, picked up two tillotson’s. The 63F is in great shape and the 87DT is rough but will get cleaned up. Also aware that a 090 carb can be used as well.
The sdc seems to be a little out of reach.

 

[heimannm]

0.003" thickness for the spring steel valves.

Sloa - remove the carburetor and muffler and make some thick rubber "gaskets" to cover the openings and use the carburetor and muffler to seal the intake and exhaust. An old inner tube works well. You will need to make an adapter to install in place of the spark plug in order to apply pressure and vacuum to test the crankcase.

PTO and flywheel side seals are the most likely source of air leaks so go ahead and remove the clutch and flywheel/points cover and points. It is possible for the gaskets in the intake tract to leak if the screws loosen up. To correct them will require disassembly of the fuel tank since two of the screws that hold the intake down are in the fuel tank. It is also possible for the crankcase cover to crankcase joint to leak; there is an o-ring between the cover and the crankcase itself.

The larger SDC carburetors (SDC18 and higher) have the same venturi and throttle bore size as the MAC and Tillotson HL carburetors used on the saws. There were adapters to allow the use of the SDC on 795L and Super 797 model saws. I am supposed to have some in my inventory but they have disappeared somehow.

Mark

 

[Sloa]

0.003" thickness for the spring steel valves.

Sloa - remove the carburetor and muffler and make some thick rubber "gaskets" to cover the openings and use the carburetor and muffler to seal the intake and exhaust. An old inner tube works well. You will need to make an adapter to install in place of the spark plug in order to apply pressure and vacuum to test the crankcase.

PTO and flywheel side seals are the most likely source of air leaks so go ahead and remove the clutch and flywheel/points cover and points. It is possible for the gaskets in the intake tract to leak if the screws loosen up. To correct them will require disassembly of the fuel tank since two of the screws that hold the intake down are in the fuel tank. It is also possible for the crankcase cover to crankcase joint to leak; there is an o-ring between the cover and the crankcase itself.

The larger SDC carburetors (SDC18 and higher) have the same venturi and throttle bore size as the MAC and Tillotson HL carburetors used on the saws. There were adapters to allow the use of the SDC on 795L and Super 797 model saws. I am supposed to have some in my inventory but they have disappeared somehow.

Mark

 

[Sloa]

Thanks Mark for the instructions on procedure. The super IPL does not show a o-ring at the connection. Read in previous posts 797 called for the o-ring but was dropped in the super and moto seal was used at that point. When I ran it before snow arrived with out the the tank all buttoned up Was able to run about two tanks of gas threw an auxiliary set up and sat rings . Felt confident seals held. After completely together can’t seem to pull gas .

 

[heimannm]

If the only issue is that it won't pull fuel I would concentrate on the carburetor, fuel line & pick up, and the gasket/flange where the carburetor mounts. If the crankcase is leaking so bad that it won't create the pulse needed for the carburetor, the saw could not run at all.

Mark

 

[heimannm]

Max dropped off this Titan 50 when he came to visit earlier this year. It was missing a few parts, and like all of these models needed to have all of the lines replaced.





The plumbing on these is pretty complicated, took a while to get everything sorted out and squared away. I am not looking forward to trying to reconnect the switch and controls.



The original 3 shoe clutches for these are quite rare, and expensive when you can find them. I have some oddball clutches from another small McCulloch saw with the same threads that are a bit wider but will serve the purpose.



Mark

 

[the 28inch mac man]

Hello, may I ask how I would go about pressure testing. Do I seal at manifold in air box and exhaust. If this holds then check off and if not do I remove tank and repeat with bare intake . Next if fails I remove clutch and flywheel ( soap and water).
I will also get a supply of seats as Mark stated the swelling makes the Flat back unpredictable from day to day.
I do want to run with the flat back but am hedging my options, picked up two tillotson’s. The 63F is in great shape and the 87DT is rough but will get cleaned up. Also aware that a 090 carb can be used as well.
The sdc seems to be a little out of reach.

It couldn't hurt to presure test the crankcase. As far as putting a sdc on one of these saws, I figured out a way to make one of the adapters out of some aluminium plate. I'll try to post some pics of the adapter when I get the time.

 

[the 28inch mac man]

Hello, may I ask how I would go about pressure testing. Do I seal at manifold in air box and exhaust. If this holds then check off and if not do I remove tank and repeat with bare intake . Next if fails I remove clutch and flywheel ( soap and water).
I will also get a supply of seats as Mark stated the swelling makes the Flat back unpredictable from day to day.
I do want to run with the flat back but am hedging my options, picked up two tillotson’s. The 63F is in great shape and the 87DT is rough but will get cleaned up. Also aware that a 090 carb can be used as well.
The sdc seems to be a little out of reach.

Btw if you end up doing a presure test you will have to block the dsp port as well as the intake and exhaust. It best to block the intake at the tank not the reed plate because the tank can sometimes cause a leek.

 

[Knightmax]

Max dropped off this Titan 50 when he came to visit earlier this year. It was missing a few parts, and like all of these models needed to have all of the lines replaced.

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The plumbing on these is pretty complicated, took a while to get everything sorted out and squared away. I am not looking forward to trying to reconnect the switch and controls.

View attachment 444680

The original 3 shoe clutches for these are quite rare, and expensive when you can find them. I have some oddball clutches from another small McCulloch saw with the same threads that are a bit wider but will serve the purpose.

View attachment 444681

Mark

Glad its getting completed, and has a good home!

 

[heimannm]

I have at least three different top covers for the Titan 50/57 Double Eagle 50 saws, one simply screws on like this.



There is another with a summer/winter shutter that attaches with a screw.



And yet a third type that attaches with a bail and an over-center snap.



Mark