084 Carb Diaphragm Help

[Vintage Engine Repairs]

Hi guys,

Old carb has forked lever where the old metering diaphragm would clip onto, new carb kit (didn't include lever, just a GnD kit) diaphragm doesn't have the clip, just a normal button.

From memory the forked lever and non clipped metering diagram still work, but wanted to put it past people here.

Old diaphragm left with nipple that slides on the forked metering lever. New diaphragm on right no clip.

Forked metering lever:

 

[hacskaroly]

That sucks when they change things up like that. Did you have to do any adjustments to the metering lever to get the button style to work or did it remain at the same height?

 

[jacob j.]

For one thing - your metering lever looks way too high.

 

[Vintage Engine Repairs]

For one thing - your metering lever looks way too high.

Yeah looks totally wrong. Interestingly the two carbs I took apart he dropped off had the same height.

Do you know the spec for them? They're sitting just below the edge of the carb gasket surface.

I cant find any height spec from tillitson. It's an HT2 series carb. Cheers!

Edit I found 3 carbs, all have same metering lever height, at or slightly below the gasket surface?

Any info on OEM spec height would be much appreciated as I have searched for over an hour with no luck.

 

[hacskaroly]

@ray benson do you have any documentation on Tillotson HT2 carbs, something that might have info on resetting the height on the metering lever?

 

[el33t]

I don't think the lever setting in these carbs differs from that in the HS series. So the lever should be rather flush with the inner floor for both types of metering diaphragm.
Probably the Walbro gauge for WT carbs can be used in this case.

 

[ray benson]

@ray benson do you have any documentation on Tillotson HT2 carbs, something that might have info on resetting the height on the metering lever?

084 service manual - page 75, troubleshooting chart remedies.

 

[Vintage Engine Repairs]

I don't think the lever setting in these carbs differs from that in the HS series. So the lever should be rather flush with the inner floor for both types of metering diaphragm.
Probably the Walbro gauge for WT carbs can be used in this case.


View attachment 466947

Na they're different unfortunately!

 

[Vintage Engine Repairs]

084 service manual - page 75, troubleshooting chart remedies.

Perfect Ray!! Yes that's essentially where this is set, about flush with the carb gasket mating surface (where the metering diaphragm sits). Thank you!!

 

[Vintage Engine Repairs]

@ray benson do you have any documentation on Tillotson HT2 carbs, something that might have info on resetting the height on the metering lever?

Thank you

 

[ZeroJunk]

I think you can get a complete rebuild kit with the forked lever and tab on the diaphragm. Or, at least I have in the last few years.
Sort of wonder if you got the tab in the fork correctly or not. Hard to see.

 

[jacob j.]

Perfect Ray!! Yes that's essentially where this is set, about flush with the carb gasket mating surface (where the metering diaphragm sits). Thank you!!

I don't think that's correct. If you set it that high, and install the metering diaphragm, then the lever will be open all the time.

 

[ZeroJunk]

Flush with the chamber floor.

 

[huskihl]

The forked lever works fine with the non-forked diaphragm.

I believe the lever goes flush with the lower floor as well

 

[lehman live edge slab]

Carb break down and part numbers out of ipl for 084

 

[lehman live edge slab]

Rebuild section for carb right out of 084 shop manual. No idea why it posted them sideways

 

[Vintage Engine Repairs]

@ray benson was spot on, thanks mate! Right where I had it set originally. Seemed too high originally, but runs perfectly.

I pressure tested the carb and it held. The clearance between the fork holding the needle and the top of the needle stops it being held open. Here is the first start just now after a full engine rebuild from a box of bits.

Came as a bunch of parts, literally nuts, bolts, clips all mixed with other saw parts and hardware nonsaw related (as missing a bunch of parts. I had to find what went with what saw and rebuild it from the ground up to a finished saw!

First Start:

 

[Sloughfoot]

Good on ya, Mate.