Replacement engine for BCS 948 tractor/tiller.

[oughtsix]

In regards to replacing the engine, is it as simple as removing the 4 bolts to the clutch housing and pulling the engine off, or is there a bolt/screw that secured the clutch to the engine shaft?

There are 4 bolts holding the engine to the engine adapter plate. There are 6 studs holding the engine adapter plate to the transmission.

1) It is best to remove the 6 nuts from the studs holding the engine adapter to the transmission first.
2) Then slide the engine and clutch off of the transmission input shaft.
3) Remove the clutch. I am familiar with 3 styles of clutches.
a) Original ACME motor clutch. I forget how the clutch mounts to the engine shaft... that was 30 years ago.
b) Older style Briggs/Honda motor. There is a set screw and shaft key that holds the clutch onto the engine output shaft.
c) Newer style Briggs/Honda motor. There is a hex head bolt that is accessible from where the transmission shaft enters the clutch. The hex bolt goes into the end of the motor output shaft. With the right hex key it took considerable KROIL (penetrating oil) and a lot of torque to break this bolt free. It took me a while to figure out where this retaining bolt was on my new to me 948. You can't really see this retaining bolt you just have to poke around for it with a hex key.
4) After the clutch is removed from the engine shaft you can remove the 4 bolts holding the engine adapter to the engine and slide the engine adapter off.

EVERY time I have removed an engine I ALWAYS take the 4 bolts holding the engine adapter to the engine first (WHICH IS WRONG) and then am stuck with not being able to remove the engine until I remove the 6 nuts on the studs that hold the engine adapter to the transmission. I.e. You can not get the engine off of the adapter plate until the clutch has been removed. You can't remove the clutch until you remove the engine adapter from the transmission.

Make sense?

It is really not a very difficult procedure. It does take some alignment and huffing and puffing to get the Engine + Adapter plate + Clutch back onto the transmission. I use a floor jack under the engine to get it to the right height so everything lines up. An extra set of hands would be very helpful during this operation.

 

[oughtsix]

The 948 has built in (add-on) weights that are on the engine side of the axle. I found that the balance on my tractor made it almost unusable for anything other than the 34in tiller box, so I took the weights off and had the tires foamed. The balance is much better now.

I don't believe that my 948 came with any extra engine side weights. My 948 had been through a fair amount of "tinkering" before it made it to me so the weight might have previously been removed.

My 30" combo motor with the 3" extension balances nicely with the new heavier 459cc engine. My 28" snow blower is spline drive so I will have to buy and adapter if I want to use it on the 948. I am most worried about the balance of the new engine with the snow blower.

Are you using quick hitches for your implements on your 948? My 30" tiller uses 3 mounting studs instead of the usual 2 studs. This made me kind of nervous about using a 2 stud quick hitch for the 30" tiller... I assume the 3rd stud is there for a reason... like the extra weight of the 30" tiller.

Do you use quick hitches?

 

[oughtsix]

Thanks for the detailed post. Good to hear it has worked out OK.
I must look at the clutch on our 732, I had Earthtools rebuild it several years ago, now I need to adjust it or get a bigger left hand
I'm in the middle of replacing the 250cc B&S (blown) engine on our Ariens snowblower with a 420cc.

On my ancient Mainline BCS tiller the clutch was almost impossible to release with the hand lever. After a lot of tinkering I replaced the clutch cable then the clutch was easy to open with the hand lever.... just a thought.

P.S. I have a 420cc HF motor on my ancient Mainline BCS tiller. I am very impressed with it! The extra loft and distance I get with the 420cc engine with the 28" blower is impressive. I have had a few neighbors comment.

 

[jbradley]

...

Do you use quick hitches?

Yes. The 948 that I have came with the 34-in tiller box bolted to a 3-bolt 3-in extension. I took the top center stud off of the extension and added the quick hitch. I have a 30-in tiller that I use with the quick hitch. The extra 3 inches of extension make the balance a bit better for other implements. It's still rear end heavy with the snow thrower and sickle bar mower (45in oil bath).

 

[m7040]

I replaced the original Acme 10 hp with a Kohler electric start from Earthtools:

 

[jbradley]

...

Thank you. I was wondering if I needed to take apart the clutch cable and lever (I need to at some point to replace the rubber boot), and your post lets me know I don't have to do that at this time.

Edit. After initially posting this, I went out and got the engine and clutch off of the tractor. Now, to get the clutch off the engine. It started to rain, so it will have to wait a bit.

 

[5030]

Don't know squat about BCS 2 wheel tractors but I do about Honda and HF engines. After I tossed a rod on a 13 horse Honda with 9 hours on it and was denied warranty. that crapper went to the landfill and got replaced with a Pred. In fact, all my small engines are Preds now. Good engines, good price.