Sump Gasket Leaking

[mekelly]

I own a Craftsman riding mower with a Briggs 28M707 engine.

The sump gasket is leaking oil and I need to replace it.

Several questions:

- There are 3 different gaskets available (different thicknesses), I assume I should get the standard thickness .015"?
- Are there any gotcha's for this job?
- What's the torque spec for the sump bolts and the bolts that mount the engine to the mower?
- Should loctite be used on either the sump bolts or engine mounting bolts?
- Anybody know of a step by step tutorial for this job?

Thanks!

 

[mechanic mark]

https://www.google.com/search?sourc...962&oq=b&s 270962&aqs=chrome..69i57.13619j0j8
click on first PDF for manual

https://www.google.com/search?sourc...ket on b&s engine&aqs=chrome..69i57.47806j0j8
watch videos

 

[Tinkerer200]

I own a Craftsman riding mower with a Briggs 28M707 engine.

The sump gasket is leaking oil and I need to replace it.

Several questions:

- There are 3 different gaskets available (different thicknesses), I assume I should get the standard thickness .015"?
- Are there any gotcha's for this job?
- What's the torque spec for the sump bolts and the bolts that mount the engine to the mower?
- Should loctite be used on either the sump bolts or engine mounting bolts?
- Anybody know of a step by step tutorial for this job?

Thanks!

I can send you a Service Manual/Overhaul Manual for your engine IF you like. Address below, put in proper format and remind me engine model number and what you want.

Walt Conner
wconner5 at frontier dot com

 

[mekelly]

https://www.google.com/search?sourc...962&oq=b&s 270962&aqs=chrome..69i57.13619j0j8
click on first PDF for manual

https://www.google.com/search?sourc...ket on b&s engine&aqs=chrome..69i57.47806j0j8
watch videos

Thanks for the links. The manual doesn't state what the torque specs are for bolting the engine to the mower frame. Does anybody know what they are?

 

[mekelly]

As I am going to be removing the motor to replace the leaking sump gasket, is there anything else I should do when I have the motor off the mower?

I am not looking for extra work just for works sake, but obviously want to do whatever makes sense mechanically to take advantage of the situation.

The following come to mind:

- Replace head gasket
- Adjust valves
- Replace PTO seal

Should I mess with the head gasket if it's not leaking? Anything to take off the list, anything to add?

 

[bertsmobile1]

If you are gong to split the cases, then I would go the whole hog.
Gaskets are cheaper if bought as a full overhaul kit, you pay for them all use all of them.
The upper & lower oil seal will get damaged when you take the crank out so at a minimum you will need to replace both of them.
The different thickness gaskets are there to control the end float of the crank.
If it is an old motor good chance you will not need any.
If your engine has a thrust washer under the crank replace it as well.

Pull the flywheel off while the engine is still bolted down to the mower, it is a lot easier as you can put a big bar under the flywheelto put a lot of load on it so you don't need to smack the end of the crank as hard.
When removing a crank like that I like to put a jack under the bottom pully / crank, just touching it so the crank does not slam into the lower case when you smack the top of it to break the seal on the taper.
Remember the crank only needs to move a few thou to break free so 2 turns on the retaining nut or bolt is more than enough .

I was given an engine to fix where the owner had smack the end of the crank so hard, it hit the bottom case & cracked it right around the lower boss.
The other big mistake is to heat the flywheel then give it some , not quite so gentle taps, usually resulting in loosening or dislodging one of the magnets.