2005 Bolens Lawn Tractor - oil cap left loose and now it smokes out the muffler profusely

[ukiltmybrutha]

Someone checked the oil level (perhaps overfilling it) and then forgot to tighten the cap. Someone else then began to drive it.

I don't know how much oil escaped before it was noticed.

Start the mower, it mows fine for about a minute and then starts letting out massive smoke stacks.

Rumor has it that it isn't really overfilled at this point.

Asking here first because I can't get to the mower right now.

What could the causes be besides an overfilled crankcase?

Briggs engine info...

31A6070458E1

I/C 502cc 15.5 HP

Compression is about 90 PSI cold.

Someone said if it is an overhead valve Briggs then it is likely a head gasket. I am not much of an engine guy but think this is an overhead valve engine.

Any ideas?

Thanks!

 

[ukiltmybrutha]

Pic of the engine. Any pointers or troubleshooting suggestions? Thanks.

https://imgur.com/a/bAo0hGG

 

[ukiltmybrutha]

I am now thinking this is more fuel related. The issue seems to only manifest itself when mowing and hot. It surges like it is low on fuel then dies. During the process of dying, smoke comes out of the airbox. My sense of smell has never been great but I would be willing to guess the smoke is fuel not oil.

 

[ukiltmybrutha]

Replaced carb with a known good one. With intake disconnected so I can see right to the carb butterfly I observe the following:

1) Little to no smoke from the intake when the lawn tractor isn't moving and blades aren't disengaged.

2) Synchronous puffs of white appearing smoke once the blades are engaging and the lawn tractor isn't moving. My nose isn't great but it might smell like fuel.

3) With blades engaged and moving, there is even more smoke from the intake and out of the muffler. Smell from muffler smells like oil to me. The lawn tractor will die in about 10 seconds in this condition.

Any ideas?

 

[Rivets]

All symptoms of a blown head gasket.

 

[ukiltmybrutha]

Hi, I replaced the head gasket and now it smokes oil all the time and exhibits the same symptoms. No more smoke coming from the carb though. Any other ideas?

Thanks.

 

[slomo]

I replaced the head gasket and now it smokes oil all the time and exhibits the same symptoms.

Did you lap the head and block area where the gasket sits?

Or just chunk on a new gasket and over torque the bolts?

 

[slomo]

For that known to toss head gasket engine, I would use a solid copper gasket from Bert's friend that makes them. Bert has the info on this known good fix.

 

[ukiltmybrutha]

Did you lap the head and block area where the gasket sits?

Or just chunk on a new gasket and over torque the bolts?

Uhmmm, do you mean like lapping valves? I did not go to that extreme. However, I did what I would say might be the "averagish" person would do and carefully clean up the surfaces, follow torque specs and torque sequence.

 

[ukiltmybrutha]

For that known to toss head gasket engine, I would use a solid copper gasket from Bert's friend that makes them. Bert has the info on this known good fix.

So you are thinking this is still a bad head gasket? Who is Bert? I followed a few youtube links carefully.