McCulloch 250 Guide Bar Question

[Okie]

Here is a link to a Tillotson HL63E carb for sale that can be used on several of the McCulloch chainsaws. (as mentioned above)


The Tillotson HL63D, E, and A can be used interchangeable and use same kit and can also be used in place of the 87D, but the 87 D cannot be used to replace the 63A, D, E,
because the 87D does not have a choke butterfly inside the carb.

I suspect it will work on a 250 but not sure. I know it will work on the 1-40 and 1-50 series of McCullochs saws. (I do not own a 250, but it appears to use the same carb set-up as the 1-40, 1-50 series saws)


https://www.ebay.com/itm/McCulloch-...809491?hash=item5b3fb45f93:g:Ip4AAOSwhpZZ6x2j

I've bought used and new Tillotson carbs for less than this $29) with careful shopping and not being in a hurry!

You have to be careful and not use over about 15-20 lbs of air pressure on the Tillotsons or you can blow out the welch plugs if direct injecting the air into the passages. (keep the air nozzle back away from the carb ho9les when using air)

 

[brian.b]

You are not the only one to have this question, and I have first hand experience with it. Yes it will pull a 36" but it will not like it. I outfitted mine with a 36" 3/8 0.050 Stihl bar with very few modifications. Grind out the oiler, and add bar plate, as well as stud spacers. If you want any more pics on the modifications to run a Stihl bar, let me know as I have some more. I ran the chain tighter than I should have the two times I ran it, but I am still doubtful that it would havr run much better.

I know this is an old thread but I was getting ready to try and do just this can you please send me the pics of your modifications if you still have them thank you

 

[Mac&Homelite]

I know this is an old thread but I was getting ready to try and do just this can you please send me the pics of your modifications if you still have them thank you

I don't have access to the saw right now but can get some pics in a week or so for you. All I remember doing (it's been so long now I somewhat forget what I all did) is find a spring at the hardware store that was about the right ID and OD to take up the slop in the bar slot. I think I have the bar in the shop right now and can dig it out and see where I ground for that. I actually need to get back to this project sometime here and get the saw tuned up good. It's a torque monster but no speed demon. The clutch I believe I upgraded completely with a replaceable sprocket to be able to use different chain.

 

[brian.b]

Thank you very much for getting back to me on this ....I’ve had this 250 for a while and a friend of mine had me put a 090 carb on a Mac 15 and it got me wanting to get my 250 going lol so I ordered the carb and had a Oregon clutch drummer up and switched to a 3/8 7 pin sprocket and I have an old wide nose stihl sprocket tip bar I’d like to swap on her

 

[brian.b]

The bar is 24 inch I think it should do good if these things pulled hard nose 404 lol ......but again thank you any help will be greatly appreciated....

 

[250/143/1-10 man]

Thanks, it sure didn't look like that when I got it. I would be supprised if it is even broken in yet. Cylinder was minty. Has some running issues currently, carb box keep on filling up with fuel. I never tried it with a 20" on it, but I believe that is where it's sweet spot is.

 

[250/143/1-10 man]

I have a 250 I'm bringing back to life and it's a beast, I have a question, there wasn't any markings of a 250 when I got it, on the bottom it has 143 then under it has a 45d out, then had I think 5 numbers on it, what do you think

 

[Okie]

250 New member guy:

This is a old thread you are posting at.
You will get faster responses if you will start another NEW Message post.
Briefly about your Mac saw. If it has 1-43 stamped it's probably a 143 and when all is correct it will handle a 16-20 inch bar good with the big 404 chain. 1-43 saws are ok when all is correct, just heavy to use.

As for it getting fuel into the carb air box. Most generally they will never run correct when that is going on, especially under a full load cut.

It is quite common for the gas line to leak at the bottom of the carb on the barb especially if it still has the old Mac clamp. Get a small gas line hose clamp that has the 1/4 inch hex head so as it can be secured and replace the line if it's hardened. No much operating room in that area.
I've replaced that fuel line using tygon.
If the leak is not at this place you can then remove the carb and do as pressure test.
Maybe someone will post the test procedure but briefly I seem to remember just use about 5 lbs of air and check the gaskets for seeps and can place the carb under water to inspect for bubbles.
Be very careful when removing the bottom on the carb, the one center screw and try to remove and save the gasket and clean the sinter iron screen by using air pressure.
Some (most) of the kits have the wrong size cork gasket for this area. Most generally the old cork gasket will reseal if not mutilated, etc.

What is the numbers stamped on your carb flange? (like HLXX or what?)

 

[250/143/1-10 man]

250 New member guy:

This is a old thread you are posting at.
You will get faster responses if you will start another NEW Message post.
Briefly about your Mac saw. If it has 1-43 stamped it's probably a 143 and when all is correct it will handle a 16-20 inch bar good with the big 404 chain. 1-43 saws are ok when all is correct, just heavy to use.

As for it getting fuel into the carb air box. Most generally they will never run correct when that is going on, especially under a full load cut.

It is quite common for the gas line to leak at the bottom of the carb on the barb especially if it still has the old Mac clamp. Get a small gas line hose clamp that has the 1/4 inch hex head so as it can be secured and replace the line if it's hardened. No much operating room in that area.
I've replaced that fuel line using tygon.
If the leak is not at this place you can then remove the carb and do as pressure test.
Maybe someone will post the test procedure but briefly I seem to remember just use about 5 lbs of air and check the gaskets for seeps and can place the carb under water to inspect for bubbles.
Be very careful when removing the bottom on the carb, the one center screw and try to remove and save the gasket and clean the sinter iron screen by using air pressure.
Some (most) of the kits have the wrong size cork gasket for this area. Most generally the old cork gasket will reseal if not mutilated, etc.

What is the numbers stamped on your carb flange? (like HLXX or what?)

Mine is the HL87D carb, it has a broken throttle where it screws on so I bought a Stihl carb and it was the same, I haven't got it to fire yet, just got it all together

 

[Okie]

What is the Stihl part number of the carb you mention?

Did you have to mod the throttle and choke linkages very much?

 

[250/143/1-10 man]

What is the Stihl part number of the carb you mention?

Did you have to mod the throttle and choke linkages very much?

Q