Engine Rear Rider Engine Replacement

My 8 or so year old RER engine gave up mowing heavy wet grass and needs a new engine. The blown engine is a 9 hp B&S 28B702-1154-E1.

My Snapper dealer says the replacement engine is a 12.5 hp B&S 217902-0015, and he wants $900 to do it. Obviously, he wants to sell me a new mower.

I have checked on line and both a B&S 219702-0115 (12.5hp) and 215702-0115 (10.5hp) are suggested as good replacements if you buy a Snapper muffler to fix the interference with the left grasscatcher support. The 12.5 hp is actually a little cheaper ($365, shipped).

I hear the switch is quick - a couple hours.

Does anyone have any experience installing either of these engines, or would be willing to suggest another similarly priced replacement. I would like to get out of this for less than $500.

Should be a stay forward engine swap without any major mod work required.

This is a follow up to my post last year. To tide me over the summer, I bought a $200 JD beater that performed pretty well, but is on its last legs.

At the same time, I was scouring Craigslist looking for a replacement engine for the Snapper. This week, I bought the exact same engine that died a B/S 28B702-1154-E1.

Now I need to replace it. Is it as simple as:

unbolting the old motor and pulling it out
Removing the drive disc from the old engine crank (after measuring its exact location)
Installing the disk on the new engine crank
Putting in the new engine

The drive system is friction, I think, so if I install the drive disc in exactly the same location, I shouldn't need to adjust it - correct?

Since the mower is 12 years old, will I have trouble getting the old drive disc off? A couple of drops of Marvel Mystery Oil and a couple taps with a hammer if it's subborn? Or should I just pony up for a new disc?

Since it will be apart, is there anything else I should check on the drive system? It was running fine when the engine went south.

Thanks for your help - I am not a mechanic, but I do have tools and basic knowledge.

Lou

I can see from the first that you think changing a engine is a quick easy two hour job. You are living in a dream world. You are going to find a lot of hidden little problems. That being said I really don't think you should not do the job, but be prepared to not have things go that perfect. Yes you will have to make adjustments and you will find things take more then a little oil and a light tap with a hammer. I have been doing this work for the last 60 years and have never found two jobs alike. The best of luck on this Nick

Nick,

Thank you very much for your words of encouragement. In sixty years, I'm sure you have seen most, if not all.

I really was looking for some more practical tips, though. Since the engines are identical, all the wiring and mechanical should be the same.

One potential issue I see is removing the drive disc from the old engine crank. I plan to pull the engine and put penetrating oil on it if it doesn't come off with a little persuation. Given I live in Maine, I have a couple of months for the oil to loosen things up. If it's still stubborn, I plan to put some heat on it, and if that fails, rent a pulley puller.

Does anyone have some hands on experience with removing the discs without damage - they are $70 bucks new.

Thanks

seabrz said:

One potential issue I see is removing the drive disc from the old engine crank. I plan to pull the engine and put penetrating oil on it if it doesn't come off with a little persuation. Given I live in Maine, I have a couple of months for the oil to loosen things up. If it's still stubborn, I plan to put some heat on it, and if that fails, rent a pulley puller.

Does anyone have some hands on experience with removing the discs without damage - they are $70 bucks new.

Thanks

Click to expand...

Seeing you are not going to save the old crankshaft I really don't see why you couldn't drill it out to remove the disk on the old engine. The problem you will have with heat I think the disc is rubber and won't take much heat. I have found just put some penetrating oil overnight and a good chance all it will take is the light taping with a hammer to remove. I have found they don't come off that hard and it wouldn't suprise me is then you take the bolt out that holds it on it will come right off with your hands. Also seeing it is the same outfit maybe you won't need to remove it? You shouldn't have any wiring or throttle cable problems if they are both the same type machine but don't count on it because I find they do change things from time to time.

Nick,

Thank you very much - I can only hope you are right. The old engine threw a rod through the side, and short blocks are no longer available. No idea what caused the failure - it happened about an hour after I changed the oil, and the weather wasn't that hot, either.

The mower was always under cover and is otherwise in good shape, so I am hoping that the disc isn't seized to the crankshaft, and the penetrating oil and tapping does the trick.

The new (used) engine I found is the exact same model and type as the old one B&S 28B702-1154-E1, so I have a lot of extra parts (as long as the lower engine stays in one piece).

Thanks again,

Lou

reynoldston said:

I can see from the first that you think changing a engine is a quick easy two hour job. You are living in a dream world. You are going to find a lot of hidden little problems. That being said I really don't think you should not do the job, but be prepared to not have things go that perfect. Yes you will have to make adjustments and you will find things take more then a little oil and a light tap with a hammer. I have been doing this work for the last 60 years and have never found two jobs alike. The best of luck on this Nick

Click to expand...

I found a replacement B&S engine for $150. Using a Sears socket kit, a couple of open ended and allen wrenches borrowed from my neighbor, a screwdriver, pliers, hammer, and a framing square (to measure the drive disc depth), this change took me 2 hours. Would have taken less time, but the disc took 30 minutes to remove. Guess I got lucky.