Con rod explosion :O

[H_L]

Hey guys,
I have a Briggs and Stratton 11.5HP and it needs a new con rod.
I have the service manual and it states a 494504s rod-connecting (standard) then it says: note 495490 rod-connecting (.020" Undersize)
Wondering which one to order?
On the side of the rod itself it says 28 OHV and on the other side of the rod it says 34
I can't find much information about it at all, there's not many photos of either rod on the net and if I find a 494504s on the net it has 28 L-head on the side of it.

Question: Is my rod a 494504s or 495490?
Question: Is a OHV rod the same as a L-HEAD rod?

Engine numbers are:
Model: 28D707
Type: 1126-E1
Code: 001010ZD
Year 2001 about 21years old

P.s. The valves are on top if that makes any difference as I'm assuming it has OHV written on the rod for a reason??

Cheers

 

[StarTech]

First the engine is a 2000 engine according to date code posted.

In this case they are the same as the OHV used the 494504S before July 01, 1998 after which they changed it. So that is going to confuse the layman too.

But the current rods are embossed with L-head.

I believe you have the IPL and not the service manual as it is where you find the part numbers. Now as which to order you need to mike rod journal of the crankshaft and compare to the specs in the service manual. But there is a problem there as the undersized rod is now NLA from Briggs. You might find one in NOS but odds are against it.

 

[sgkent]

normally when a rod breaks it damages other things as pieces flail around. Best to get everything apart, clean and inspect closely before you spend a dime on the engine. The cylinder may be damaged as well as the crankshaft.

 

[Telesis]

Pay particular attention to the rod journal on the crankshaft. Look for aluminum deposition(buildup) on it from the excessive heat during the first failure. That can be removed pretty easily with muriatic acid. You can Google that for more details. I can tell you from experience that if you ignore that buildup and put everything back together, the engine will likely run fine... and will likely crater the con rod again and/or more in no time!

Good luck!

 

[StarTech]

One piece advice on using Muriatic Acid. Use it outdoors with the wind to your back as it produces toxic fumes when exposed to moisture in the air. It will take your breathe if not careful.

 

[Fish]

"I have the service manual and it states a 494504s rod-connecting (standard) then it says: note 495490 rod-connecting (.020" Undersize)
Wondering which one to order?"

If the crankshaft is damaged then a machine shop may resurface the area, and you would use the undersized one. The vast majority of the time it is just pasted on aluminum that can be buffed out/off.

 

[H_L]

Thanks so much for all your replies!!!
Yes the manual is the exploded view with part numbers, it doesn't go into great detail like some proper service manuals so it's more of a full parts manual.
And yes everything looks perfect, I've inspected every part real closely (I'm OCD when it comes to repairs) and it's all fine LUCKLY!! so lucky!! :O

I'm wondering if this one will work fine https://www.allmowerspares.com.au/i...-stratton-genuine-connecting-rod-494504s.html

Undersize? meaning it's a .020" smaller journal fitting

 

[Tinkerer200]

One piece advice on using Muriatic Acid. Use it outdoors with the wind to your back as it produces toxic fumes when exposed to moisture in the air. It will take your breathe if not careful.

One piece advice on using Muriatic Acid. Use it outdoors with the wind to your back as it produces toxic fumes when exposed to moisture in the air. It will take your breathe if not careful.

Don't want to be argumentative but, I have found from experience that it is best to have the wind to your side, 90 degrees, as if it is to your back, it may cause back current bringing fumes back into your face.

Walt Conner

 

[StarTech]

Don't want to be argumentative but, I have found from experience that it is best to have the wind to your side, 90 degrees, as if it is to your back, it may cause back current bringing fumes back into your face.

Walt Conner

Not argumentative at all. Your right as I forgot about the vacuum effect. It is whatever that works to keep the fumes from yourself.