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Bought a Craftsman LT1000 with a 18.5hp Briggs Model 31H777 0202 E1, was running great until I changed the oil and filter. When I started it, it started blowing blue smoke out the exhaust. I used the recommended 10w30 and the oil lever is right on where it should be on the dipstick. What is going? It puffs even mower when I turn the key off and the dies.

If it IS the head gasket, I'm going to attempt it myself. I can get the OEM Briggs gasket set on Amazon for $25 shipped with 2 day Prime shipping.

If it is an old mower then it can just be wear.
10W 30 is a lot thinner when cold than strait 30 and is might be nothing more than oil which is too thin.
If it runs OK and you can see the grass well enough to mow, then mow but change up to strait 30 or even 20W 50.

A leak down test will give you some more information.
Plain compression tests are of no use because of the automatic decompression.

bertsmobile1 said:

If it is an old mower then it can just be wear.
10W 30 is a lot thinner when cold than strait 30 and is might be nothing more than oil which is too thin.
If it runs OK and you can see the grass well enough to mow, then mow but change up to strait 30 or even 20W 50.

A leak down test will give you some more information.
Plain compression tests are of no use because of the automatic decompression.

Click to expand...

Ok, Ill switch to straight 30 and see what happens. I ordered a head gasket kit just in case. Thanks.

So I got the head off today and saw where the gasket was definitely blown in the usual spot. Problem is, I broke off 2 head bolts when I was torqueing them down. So I had to stop and take it apart again. Don't know why the damn bolts broke, I was torqueing them to specs. Now I have two bolts that are broken off about 1/2" or so from the surface. Obviously I need to drill them out and extract them. What are some quality bits I can get easily? I bought a set of Dewalt cobalt bits for the last motor I worked on and it snapped off in the exhaust manifold hole almost as soon as I started drilling so I'm not getting or using those POS bits again.

I have a question: Once the first bolt broke, why did you continue torquing head bolts?

Left Hand Spiral, Left Hand Cut is the ideal bit to drill out broken RH thread bolts. Many times, the broken bolt comes spinning out before you ever get it drilled thru.

https://www.youtube.com/watch?v=FYvaPbX1sT4

https://www.amazon.com/Neiko-01925A...=2025&creative=165953&creativeASIN=B000F9ANQW

cpurvis said:

I have a question: Once the first bolt broke, why did you continue torquing head bolts?

Left Hand Spiral, Left Hand Cut is the ideal bit to drill out broken RH thread bolts. Many times, the broken bolt comes spinning out before you ever get it drilled thru.

https://www.youtube.com/watch?v=FYvaPbX1sT4

https://www.amazon.com/Neiko-01925A...=2025&creative=165953&creativeASIN=B000F9ANQW

Click to expand...

I only torqued 2. I thought it was the torque wrench clicking, so I went to do the second one and I thought it clicked too. But it wasn't a click, it was a snap.

JonnyBlaze said:

I only torqued 2. I thought it was the torque wrench clicking, so I went to do the second one and I thought it clicked too. But it wasn't a click, it was a snap.

Click to expand...

Maybe you should get a beam torque wrench. With a click type torque wrench, you have to have a feel not only for when they click, but to know when the correct torque value has been exceeded without hearing a click.

cpurvis said:

Maybe you should get a beam torque wrench. With a click type torque wrench, you have to have a feel not only for when they click, but to know when the correct torque value has been exceeded without hearing a click.

Click to expand...

I do have a beam style but its 1/2" and only does foot pounds. Havent seen one that does inch pounds. Ill look into it.

Also, I don't even know why they snapped. I used a 3/8" torque wrench in foot pounds and set it to 12.5 ft lbs because I was torqueing to 150 ft lbs and divided by 12. So what did I do wrong?

JonnyBlaze said:

Also, I don't even know why they snapped. I used a 3/8" torque wrench in foot pounds and set it to 12.5 ft lbs because I was torqueing to 150 ft lbs and divided by 12. So what did I do wrong?

Click to expand...

I think you must mean 150 inch-pounds. Divide that by 12 and you get 12.5 ft-lb.

What you did wrong was that you applied far more than 12.5 ft-lb of torque.

How is what the question is. Head bolts are not flimsy; you have to actually work pretty hard at breaking one.

cpurvis said:

I think you must mean 150 inch-pounds. Divide that by 12 and you get 12.5 ft-lb.

What you did wrong was that you applied far more than 12.5 ft-lb of torque.

How is what the question is. Head bolts are not flimsy; you have to actually work pretty hard at breaking one.

Click to expand...

I put it right on 12.5 ft lbs. It didn't even feel like I was cranking them that tight.

How long is your 3/8" click torque wrench? Mine is about 14" from center of square drive to center of grip. That would mean to apply 12.5 ft-lb of torque to a bolt, I'd have to push or pull on the handle with a little less than 11 pounds of force.

Does that seem to be about the same amount of force as you were applying to your torque wrench?

cpurvis said:

How long is your 3/8" click torque wrench? Mine is about 14" from center of square drive to center of grip. That would mean to apply 12.5 ft-lb of torque to a bolt, I'd have to push or pull on the handle with a little less than 11 pounds of force.

Does that seem to be about the same amount of force as you were applying to your torque wrench?

Click to expand...

Ill have to measure it but that seems about the right length. Not sure about the feel of it but It certainly didn't seem like much.

If you have a vise, chuck the male end of a 3/8" extension in the vise. Put your torque wrench in the female end. Set the wrench on 12.5 ft-lb and see how hard you have to pull to make it click. Sometimes it's as much 'feeling' it click as it is hearing the click. Do the same thing with your beam torque wrench using a 1/2" extension. Compare the two.

FWIW, I'm not sure if my 3/8" clicker even goes down that low. I'll have to look at it tomorrow.