McCulloch Chain Saws

[Woodslasher]

Thought you were looking for SDC info.

I am. The saw wouldn't idle when I ran it so I assumed it was due to bad crank seals. I ordered new ones and yesterday I pulled the old ones and decided to peek at the carb while I was poking at it. Turns out I put the diaphragm in before the gasket, which held the needle open and was causing the screamer symptom. Seeing that, I decided I'd better look at the other side of the carb, which is when I saw that there were too many valve/diaphragm bits and I turned to y'all for help. But, the saw is still sitting on my bench sans crank seals.

 

[PogoInTheWoods]

I am.

I'm confused. Thought I just sent you some SDC info? Should be able to sort it out easily knowing which model is on the saw. So what model is it?

 

[Woodslasher]

I'm confused. Thought I just sent you some SDC info? Should be able to sort it out easily knowing which model is on the saw. So what model is it?

Sorry, I got confused for a bit there. It looks like the carb is a model 37A, without the accelerator pump.

 

[Woodslasher]

So, based off of the one chart, I need the nylon diaphragm and not the rubber. Just a heads up, the diaphragm is now p/n 95-25-8

 

[PogoInTheWoods]

Good deal. I wasn't trying to be contentious. Just hoping to provide information that may prove useful.

 

[fossil]

So, based off of the one chart, I need the nylon diaphragm and not the rubber. Just a heads up, the diaphragm is now p/n 95-25-8

You need both diaphragms, black to the carb body and then the brown teflon one and the thin gasket and then the cover.

 

[matt_lamb_160]

Does anybody know if the 3rd port passage is drilled on 450, 550 and s550 McCullochs?

 

[PogoInTheWoods]

You need both diaphragms,

Yes. Both 95-21 and 95-25 are used..., or at least shown.

 

[fossil]

There is an error in there somewhere and conflicting info on another. Can't remember which one it is.

 

[Maintenance supervisor]

To be honest I always use both , law of averages usually favors my ignorance!
Black rubber , tan(snakeskin) , then gasket and cover.

 

[heimannm]

The Teflon diaphragm is a backup to the rubber flaps on the fuel pump diaphragm. I don't think it will ever hurt the performance to have it in place, leaving it out may lead to flaps that do not seal completely in operation leading to low fuel delivery.

Mark

 

[edju1958]

Update on the DE80,not that anyone gives a hoot,-I went to put the carb in today & found the fuel line needed to be replaced,so hunted around for the original tank/handle that was on the saw & lo & behold,a wealth of goodies.The air filter bracket spacer plate was on there along with the 3 screws.I guess I put it back on so as not to lose it,Lol.The needle boot was still in the handle too.I also needed to scarf the 2 piece choke rod assembly .I went to reattach the one that was on the tank handle & the eyelet came out of the plastic choke knob.Now let me tell everyone here that trying to install that 2 piece chopke rod while the tank handle is secured to the engine is a real task,especially when I can't see that well.Oh,let's not forget how Mac decided to cheapen the quality of the roll pins.I never had an issue punching out roll pins till today.The roll pins they used on the DE80 saws were extremely thin & as soon as I put a vice grip on them it crushed them,or broke them off when trying to pull them out.I ended up having to drill one of the roll pins out of the original tank.After that escapade I did manage to finally get the choke rod back into place & it seems to be working properly.
This will probably fall on deaf ears,but how do I hook up the carb?There are 2 linkages - throttle & choke.I've been told that I should disconnect the throttle linkage at the trigger,but the DE80 is a whole different ball game compared to a 10 series saw.

 

[Maintenance supervisor]

I'm not familiar with the De80 throttle linkage, but would it be easier to put the carburetor on it the swing it in place instead of mounting the carb first?
Pictures?

 

[Woodslasher]

Update on the DE80, not that anyone gives a hoot, -I went to put the carb in today & found the fuel line needed to be replaced, so hunted around for the original tank/handle that was on the saw & lo & behold, a wealth of goodies. The air filter bracket spacer plate was on there along with the 3 screws. I guess I put it back on so as not to lose it, lol. The needle boot was still in the handle too. I also needed to scarf the 2 piece choke rod assembly. I went to reattach the one that was on the tank handle & the eyelet came out of the plastic choke knob. Now let me tell everyone here that trying to install that 2 piece choke rod while the tank handle is secured to the engine is a real task, especially when I can't see that well. Oh, let's not forget how Mac decided to cheapen the quality of the roll pins. I never had an issue punching out roll pins till today. The roll pins they used on the DE80 saws were extremely thin & as soon as I put a vice grip on them it crushed them or broke them off when trying to pull them out. I ended up having to drill one of the roll pins out of the original tank. After that escapade I did manage to finally get the choke rod back into place & it seems to be working properly.
This will probably fall on deaf ears, but how do I hook up the carb? There are 2 linkages - throttle & choke. I've been told that I should disconnect the throttle linkage at the trigger, but the DE80 is a whole different ball game compared to a 10 series saw.

Hey! I give a hoot! I like to live vicariously through other people's posts. My only news is one of my crank seals arrived today, so I installed that and reassembled the clutch side of the saw.

 

[edju1958]

I'm not familiar with the De80 throttle linkage, but would it be easier to put the carburetor on it the swing it in place instead of mounting the carb first?
Pictures?

That was my intention - to hook the linkages first,then mount the carb.It'd be impossible to mount the carb & then try to hook the linkages.I'm just trying to get some advice from some folks who have an 8200,or a DE80.

 

[Maintenance supervisor]

That was my intention - to hook the linkages first,then mount the carb.It'd be impossible to mount the carb & then try to hook the linkages.I'm just trying to get some advice from some folks who have an 8200,or a DE80.

Well Ed ,its like I used to tell my crew at the park, "lets go do something even if its wrong."

 

[vinnywv]

Ed when i hook up carb linkages, i do disconnect from the trigger 1st. Then hook on the throttle. Then fuel line then choke to carb and last choke linkage to choke knob.

 

[PogoInTheWoods]

advice from some folks who have an 8200,or a DE80.

8200 uses a different throttle rod. Main difference between the DE80 throttle rod and the other 800 series is how it engages the trigger. Otherwise it's essentially the same arrangement and should not pose any more difficulty installing the carb than any other 10 series saw. Just twist the carb onto the linkage (already attached to the trigger and with the retaining strap on it) and into position. The idle screw isn't even in the way as it is with an 8200. Pop the choke rod into position and secure it with the retaining strap, secure the carb, hook up the fuel line and there ya go.

one of my crank seals arrived today, so I installed that and reassembled the clutch side of the saw.

I tend to make certain that a shortblock or case passes a leak test (both pressure and vacuum) before assembling much else to it. No better time to do so. Saves having to tear the saw back apart if unexpected/erratic running issues are encountered that point to not checking for air leaks in the first place..., after you've spent time swapping ignition components, carbs, filters, fuel lines, posting here a few times, and ruling out everything else..., then doing a leak test just to discover a poorly installed new seal or not enough sealant between the oil tank/case bottom and cylinder when you put it together to begin with.

I learned the hard way before investing in a MityVac years ago. Paid for itself the first time I used it and every time it's found a leak (or hasn't) since. Wouldn't be without one.

 

[edju1958]

Ed when i hook up carb linkages, i do disconnect from the trigger 1st. Then hook on the throttle. Then fuel line then choke to carb and last choke linkage to choke knob.

The DE80 is a horse of a different color.There's no way I'm gonna disconnect the choke linkage to the knob on this b*%ch after it took me almost an hr.to connect it the 1st time.I'll see what's involved with disconnecting the throttle linkage from the trigger.I generally hook the fuel line on first as it's usually a real bugger to get on the carb anyway.

 

[edju1958]

Well Ed ,its like I used to tell my crew at the park, "lets go do something even if its wrong."

OK then,I guess I'll go do something wrong.Lol