# B&S 20hp missing pushrod



## DanTindell (Aug 25, 2013)

I lost all power and engine began spitting through the carb. This is on a John Deere Sabre (same as Scotts) 20hp 2cyl Intek B&S engine. 

I pulled the OHV valve cover off both sides and one side had a bent push rod, and the other pushrod is simply gone! I know that means it has to be in the crankcase since it's been running good and it didn't blow out the cover. 

Since the pushrod is obviously in the crankcase, that puzzles me a little because the pushrod that is missing is on the bottom which tells me the cam wouldn't be turning if it were broken and even the bent pushrod is opening the valve yet it's on top and the cam gear would be on the bottom. So how would the pushrod get into the crankcase?

More importantly, I'm fine with pulling the crankcase apart if there is a decent chance that the pushrod didn't destroy the crank/piston etc rendering my time pulling it apart useless. I hear that these intek engines have a problem with bending the pushrods due to valve guides sticking and the rocker stud backing out. I wonder if kubota or kawasakis have similar problems. I know now to check the pushrod clearance and clean yearly.

Am I wasting my time pulling it apart to get the pushrod out and repair it?

Thanks!
Dan


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## ErnieS (Jun 1, 2011)

The rods and caps should protect all of the vital parts of the crank. I'd open it up. Take some pictures. It would be interesting to see a pushrod that got sucked into the crank case.


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## garymommsen (May 25, 2010)

*Scotts 50567X8*

Would you happen to have a manual for this garden tractor? I'd be happy to pay pretty much whatever you ask for a copy.
garymommsen
715 458 4694


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## DanTindell (Aug 25, 2013)

I opened up the crankcase and the pushrod was sitting there all bent up, but there wasn't any damage to the crankcase or any core components. I replaced the head where the valve guide stuck and put it back together. .005 at TDC valve clearance on compression stroke and I'm good to go.

A little update. After researching more on this problem, it seems that B&S is not the only one with this problem. What happens is a little grass can get stuck between the cooling fins of the head causing it to overheat. It's not uncommon to see mice get in this area trying to build a nest area as well. Once this has happened, the valve guide swells enough that it sticks to the valve a little and works its way out to the point that the push rod bends. Maybe that's why they make one of them out of aluminum to bend before it gets to the point of pushing a valve into a piston?

So the options are:
- Every spring, make sure the cooling fins are clean and adjust the valve clearance
- A little bit of Marvel's mystery oil might help
OR
- Buy an engine like a Kawasaki that has water cooling so you don't have the grass problem in the air cooling fins of the head


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## Mickey (Aug 14, 2010)

DanTindell said:


> I opened up the crankcase and the pushrod was sitting there all bent up, but there wasn't any damage to the crankcase or any core components. I replaced the head where the valve guide stuck and put it back together. .005 at TDC valve clearance on compression stroke and I'm good to go.
> 
> A little update. After researching more on this problem, it seems that B&S is not the only one with this problem. What happens is a little grass can get stuck between the cooling fins of the head causing it to overheat. It's not uncommon to see mice get in this area trying to build a nest area as well. Once this has happened, the valve guide swells enough that it sticks to the valve a little and works its way out to the point that the push rod bends. Maybe that's why they make one of them out of aluminum to bend before it gets to the point of pushing a valve into a piston?
> 
> ...


Have been doing this for many yrs. This hasn't been a big issue for my Cub as the engine is turned around and cooling air is drawn in from the back side of the tractor where there is a screen that helps catch any grass clippings. The air path is completely enclosed between the engine and the area where the air enters.

Know that most small tractors use Vert shaft engines so the approach Cub took on their models with Horiz shaft engines is not possible.


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