QA42A Speed
 

Does anyone know what the ratios are supposed to be?
I have a 1/1 between the Engine and angle box and 2/1 from the box to impeller. So if the engine is at 3000 RPM the impeller is at 1500. I am not happy with the performance of it at all. It is on a 1450 and a back up to my Toro 2 stage walk behind, but it only seems to throw a few feet. The pto & belt do not appear to be slipping so that leaves about one thing left - speed.

I seem to remember someone somewhere talking about changing pulley around for more speed. Any thoughts?

They were originally designed for an engine speed of 3600 rpm.

3000 rpm is only 83% of recommended engine speed.

Also, what type of snow? Slush/wet doesn't throw far.

I run a 3.8" pulley on mine works great. I think original pulley was 4.5". What size pulley is on your thrower?

Also paint ez slide on chute and inside thrower housing will help

I haven't measured the diameter, I just marked them to find the ratio.

The snow here so far has been slush (nothing throws that) and lake effect, the type of stuff that you can blow 30' with a leaf blower. I know it is only a single stage blower and by design the Toro should always out throw it, But I feel the unit should throw more than a few feet.

Mine throws wet heavy snow 10-20 ft and light snow about twice as far. With the 3.8" pulley. If you want to try one I can look up the part number for you. Also need 3600+ rpm or you won't throw well either

I'd be interested in a part # on this, too. And a belt size, too as the stock belt would be too big? :bigthink:

Part # for me is not an issue, I do a lot of fabrication. I was just wondering what others had as far as sizes. Like I said, I seem to remember someone turning up the auger speed some by changing sizes.

Thanks.

I ran a QA42 on a 12hp Cub 106 for years and it would always have trouble with slush but I had swapped out the pulley for a 3.5 stock pulley from Ace hardware, cast iron Not aluminum(they won't hold up) goood snug belt, well painted blower housing and chute. It would put snow out to 20' feet depending on conditions but always got it off the drive.

Cast Iron V-Belt Pulley
4.15" OD
Bore size
3/4"
Each
$17.69 Each
McMaster-carr part number 6204K22

All come furnished with a set screw.

Cast Iron
OD 4.15"
Pitch Diameter for Type A V-Belt 3.4"
Pitch Diameter for Type B V-Belt 3.8"

this is the pulley i run on my 1650 works great. i guess its actually 3.4" diameter for our application. get a good tough belt and run tight as you can get it and your in business!

i believe i had to go 1" shorter on the belt but i didn't write the number down sorry.

Thanks guys, If I have time tomorrow I'll pop the blower off and measure up what I have. From looking at it I would guess at least 4", time for a smaller one and speed things up some.

QA 42 speed
 

I don't want to beat a dead horse but also don't want to start a new thread.
I also have a QA42 on a 129 seems like all i have been getting since i got this was wet snow.
The past summer disassm cleaned and panted the auger shoot and insdie of body with a graphite paint.
First show of the year wet but shoot blocked up first and it actuly stoped the auger it's self.
Am i doing something wrong? I can not believe this thrower is this prone to stoppage as much as it has been.
Thinking of doing the pulley upgrade but just wanted you're guys thought that have been using them more then i have.
Please help with any help i'm thinking i made a big mistake buying the thrower now
Thanks
Tony

If your plugging up and you already painted the chute order the pulley i mentioned in a previous post and buy/borrow a tachometer to get your Rpms up to 3600-3800. Make sure your governor is set right. If that still doesn't do it try taking a smaller swat and drive faster! You need to work that 12 horse pretty hard to get wet snow to throw good! But it will do it if set up right!

I just used my qa36 for the first time today. It's on a 123 and I was impressed as to how well it threw the snow. The snow was wet and had sleet mixed in but, it threw it really good. I used pb blaster dry lube on the chute and that worked good too. I do have a problem with the belt tension screw though. Had to tighten the belt a few times.

Thank you John
I am a mechanic by trade and have a multimeter with the tach setting at work and plan on bringing it home and checking the RPM's out after seeing your prior post.
I just have a hard time believing that i am the only one that has ever tried to blow wet snow with this setup and as good as these tractors and other attachments work with the tractors can see the snowthrower being it's down fall.
Where do you get the pulley mentioned? Do one of the sponsors carry them?
Thanks Again
Tony

I get mine from McMaster.com. It's a pretty generic pulley I'm sure you could get one locally also. I tried three sizes before I settled on the current one. In light snow I actually slow the engine down a tad that's how good it works now. Of course I've got 16hp so I can fill the thrower better than you'll be able to. From what I've seen the fuller the thrower is the farther it will throw it.

I'm pretty sure mcmaster carr's part number is 6204k22.

I didn't want to post this twice in the same thread but here ya go!

i did measure my pulley and it is the 4.5 outside dia assuming stock pulley
I looked on McMaster-Carr's sight ans found the number you suggested what confuses me is the number you gave shows a 4.15 outside dia is this right if i have a 4.5?
also i don't understand the pitch dia for type A and B belts how is this measured?
If you don't mind me asking what other sizes did you try? and do you think going a bit smaller with the lower HP is good or not?
Muzzy how often do you have to reapply the pb blaster? just once per use or mid way through?
Tony

I only put it on once and used it for about 4 hours. It's my first time useing a snowthrower so, I'm new at it.

Same here got this one late in the season last year didn't do a thing to it just put it on the tractor had some issues the little i did get to use it
took it all apart this summer sanded it painted with graphite paint augger and body replace bergs and chain hoping for the best and did get out of it what i thought i should.
not sure if the blower is just to big for the engine size or what.
gonna try the pulley change and see what that brings

If you do get that pulley you're gonna need a shorter belt too.

Best I can tell the pitch diameter is where the belt rides. Our belt is equivalent to an A belt so effective diameter would be 3.4". I tried a 2/1/2 pulley first, way way too fast and belt slipped all the time. Then tried a 3.25" pulley which was good but a too fast for fluffy snow so I went to this 3.4" now and 90% throttle with light snow is perfect! And if it's wet heavy stuff then I'll give her wide open throttle. I found if you run it too fast with light fluffy stuff you end up wearing it all! So I just adjust the throttle according to how wet the snow is. Your results may vary but two years worth of tinkering has led me to this setup.

can't argue with experience

macman81
going to place my order for the 6402K22 pulley in your opinion you think this is the hot set up? thanks again
Tony

Well.... Best of what I tried for sure. Have used it three times in the past two weeks and I'm very happy with it. To me any smaller didn't really yield better performance and of course too fast is harder on your equipment. You'll be happy with it I'm sure of it :)

got checking the governed speed and came up a litter to low can anyone tell me what the proper way is to adjust the governed rpm's?
Was searching but didn't have any luck
Thanks
Tony

I'm not 100% sure, but it seems like you will need to adjust the linkage between the carb. & governor arm.

Should be able to adjust the throttle cable to pull farther.

No.

This is correct.
aldiesel,
Go to our technical section "tractors" download the "K" series service manual. It will tell you everything you need to know. If you can't find it, let us know and someone will post a link.

aldiesel stated the GOVERNED speed was low. By adjusting the throttle cable will not change the governed speed. The maximum governed speed is controlled by the fly weights on the governor.

If the throttle cable is not adjusted correctly the engine may not be allowed come up to the speed that would kick the governor. However I have seen cases where the linkage was not set correctly and that will indeed change the governed speed up or down.

No, maximum governed speed is controlled by the tension on the governor spring, not the weight of the flyweights. The weight of the flyweights is proportional to the size of the spring. High idle, no load, is set by the throttle stop "bar" on the engine mounted throttle lever. The linkage on the governor arm and throttle arm controls sensitivity. I really think he was referring to "high idle, no load".

well let me tell you what i did up to this point... found a link to a cab gov adjustment http://cubfaq.com/govadjust.html and what i did was loosen the pinch bolt rotate the gov shaft CCW and pull the arm away from the carb this did absolutely nothing for the speed
i dropped one hole on the arm with the spring and i got 3650 rpms no load but now a have a light surge in the rpms
should i change the spring location on the control bracket or adjust the rod length at the top of the carb??

Ok. I know you probably just read over what was posted, but just going to say it again, in case you missed it. I also notice your not really a new member, so you should already know.... In the "Technical" section, under "Tractors" go download the "K" series service manual. It will tell you, how to adjust the governor, throttle linkage, high and low idle, and anything else you want to.
Just to help you out a little.... You did adjust the governor correctly. No, doing that won't change the speed. I'll say this again. Moving the linkage to different holes won't either. That just changes the sensitivity of the governor. To adjust the "High idle no load" you move the throttle stop. No, do not adjust the rod at the top of the carb. That will do nothing except throw off all adjustments you already made. TBH, I don't know why that is even adjustable. Really I think it is only threaded so that the ball and socket joint can be replaced. It does nothing for tuning.

You are kind of making a habit on this thread of asking questions that have been answered within the body of the thread. Please read through to make sure you aren't asking a question that has already been answered. :beerchug:

This surge you mention could be a lean fuel mixture. Try pulling out choke slightly if it goes away turn the main fuel screw out 1/8-1/4 turn should go away.

OK guys let's end this, If he can get 3650 rpm out of it he is above the rated HP RPM.

We ALL know that a few hundred RPM one way or the other is not going to make much if any difference in performance. This is becoming more of a textbook question rather than real life.

I agree with both gmbadgley and J-Mech i have reread the post did looked around the best that i could clicking on every post that even mentions a implement speed lets face it i'd be here all day and when i reopened to this post i did say i did mean to beat a dead horse.
But in my defence i may be ignorant to simple skills as to setting up a garden tractors governed speed and what not but if anyone else would look back i got several different answers to the same question i am just trying to figure out what works for me that's all.
You say changing the linkage will not change the speed but i found out first hand it did work for me weather it is the proper way i don't know maybe it was just holding the throttle close i DO NOT know but it did change by 600 rpm's now i have a surge i was asking about that not the governed speed.
Thank you all for all your help and all the suggestions you have made i will figure the rest out myself
Thanks Again
Tony

Did you try my suggestion about correcting the surge? Let me know if that doesn't help.

Yes macman81 i did and it seemed to help alot but still a bit there seems to smooth out if left at high idle no load did the choke as you said then adjusted crarb.
Think i'm gonna wait for the pulley and the next snow to see what happens.
But as you said it was off 600 rpms so i can see just that making a big differents fine tuning i got it to run 3640 no load with the blower running and rpms stable it stayis 3590 3620
Thanks Again
Tony

Used my QA42A for the first time on my 782. So far not impressed with a 4 inch pulley. I had modified a Case hi-cast 38 inch on a MTD GT that did not care wet or dry snow. Wet (20-30ft) tossed better than dry which made me curious about all the posts on thrower or blower. This guy barely gets snow over the side. Bought an adjustable from grainger for the next time. It can go down to 3 inches.

Will note the belt sits very low in the engine pulley so appears quite worn and hurts my gearing. going wider than 21/32 too. Sure wish a 6 inch PTO pulley was easy to do.

Just try mine for the fourth time with a 3 1/2 inch pulley! My thrower broke again! I cant believe it! So far the belt explode, the front shaft disconnect, the chain master link broke and now the rotor don't move! The pulley move, the drive shaft move, the chain is perfect and well lube! The small sprocket don't turn, I don't know what hold that sprocket on the shaft yet but it's number one suspect on my list...

Now the way I see it, this POS may never work or get finally ready next SUMMER! :angry: