Is this head gasket blown?

[Tooljunkie]

do I need a torque wrench and angle gauge to make sure all the bolts are calibrated right when I put the engine back together?

Torque wrench and i use a little paint to index bolt for torque angle when needed. An angle guage is much closer. The valve setting i was referring to is called valve lash in some manuals.rocker gap i guess is another term. When cleaning off old remnants of gasket use care not to score the gasket surface.

 

[Lzybmbjj30]

There's a place that sells a spray tester kit not far from me for like $35 to see if there are any cracks. Do you think this is a good idea?

 

[Thorny]

Before moving forward with your assembly, PLEASE clean your motor. That big pile of mud next to the rear most cylinder and what appears to be a leaf blown into cylinder #2 make me cringe. If that dust and dirt are inside your cylinder they are going to get between the rings and the cylinder wall and you are going to have little to no compression after you start running that motor again. It may smoke now, but it's not going to start if you have no compression.

If it were mine, I'd be pulling the block out of the tractor to clean it correctly. If you drop a crumble of dirt down into one of those bores, you'll never get it clean without tearing the whole thing down, and this issue with what o ring to use on the oil pipe won't mean jack.

Sorry to be so blunt, but I think it's better to know than not know. At this point your motor can be torn down and cleaned. After you score the cylinders with dirt you'll be tearing it down anyways and replacing rings and replating the bores.

 

[Lzybmbjj30]

Oh that sucks to be honest I actually put it back together and fired it up a few times not knowing. I was just trying to see if it would run for a bit. It's back together with the old gasket. I'll be sure to replace the old one once I know what caused the gasket to blow. I'm hoping it's just a warped head so I can just have it smoothed. If the head is cracked can that be patched or does it need to be replaced? I wanted to make sure it wasn't exposed to the elements. There were some leaves that fell on it as I had it off. Hopefully I didn't do any permanent damage.

 

[Thorny]

If I were in your shoes, here's what I'd do:

-don't run the motor unless it's an emergency
-order that new gasket
-order any other parts you may need

When you are ready to do some work on it:

-clean the motor area as clean as possible, so there is zero chance of any dirt falling into it when you open it back up. If at all possible drag it into a garage or shed or shop before opening it back up to avoid the wind blowing crap into the motor. (everything sticks to an oiled cylinder wall, so if a gust of wind blows a wave of dust over the engine when it's opened up bad stuff happens.)
-take the head back off and inspect the cylinder bores with a bright light, looking for any scratches or scrapes which would indicate that dirt was rubbed up and down by piston rings. Also run your fingernail around the bore of each cylinder feeling for any nicks that you can't see with your eyes.
-rotate the crank shaft so the pistons are in different positions and do that same inspection again. hopefully you got lucky and there is no damage. If there is damage, talk to a local mechanic.
-If you need to leave the head off for an extended period of time, you need to find a way to seal up that rest of the engine. Stuff the bores with rags or paper towels and wrap the block with saran wrap or a big plastic bag and hold it in place with duct tape or something. Same goes for the other connections that you take apart.

Motors aren't real hard to work on, but they've got to say clean on the inside. especially diesels that need to make high compression in order to run.

 

[rbargeron]

I've been watching this thread and I think it has somewhat gone off the tracks. It would have been better if more troubleshooting had taken place before the head was removed. To answer the original question, the head gasket in the pics was not blown.

Now that the head is back on using the old gasket, the first startup distributed whatever dust got in so the solution to that is changing the oil and filter and hope for the best. No point in taking it apart again until more tests are done.

What were the symptoms before the head was removed? Can't tell much from the video. Is the smoke from the vent tube or somewhere else?

 

[Tooljunkie]

I agree with rbargeron. Pinpointing the source of the smoke is priority. Its a leak, it should not have changed up to this point.

 

[Ascott172]

I replaced the head gasket in my g1800 last year. The themostat went bad and it overheated. The gasket was $35. The repair manual was more than that but it was easy. I left the intake and exhaust manifolds attatched to the head and removed it as an assembly. The head had 14 bolts which I reused. The book had a torque procedure as well as a retorque after 30 minutes or running. If you need the instructions I can give them to you.

 

[Lzybmbjj30]

Thanks, I appreciate it. Okay so I did like you said and took it apart and felt around in the piston rings, I didn't notice any scratches as it feels perfectly smooth except around the very top of the ring like its slightly rough almost like carbon buildup. Not sure if that's normal or not.

 

[Tooljunkie]

The top little bit of every cylinder wont be As shiny, the sealing rings on the pistons dont go right to the top of the bore.

 

[Lzybmbjj30]

I replaced the head gasket in my g1800 last year. The themostat went bad and it overheated. The gasket was $35. The repair manual was more than that but it was easy. I left the intake and exhaust manifolds attatched to the head and removed it as an assembly. The head had 14 bolts which I reused. The book had a torque procedure as well as a retorque after 30 minutes or running. If you need the instructions I can give them to you.

So is it likely that your engine wasn't cracked or warped and all you had to do was replace the head gasket?

Another question I have is , Is it likely that my head gasket was perfectly fine and I just removed it for no reason? Now it's just a matter of replacing the old one and finding out what the real problem is.

 

[Russell King]

Yes that seems to be the consensus.


Sent from my iPad using Tapatalk

 

[Thorny]

Thats encouraging that the bore is in good shape.

When re-assembling it's important to tighten the bolts in the right order and to the right torque spec. That'll help the head seal correctly and completely.

Back to the real leak: can you see any wet areas on the side of the engine block below the head all the way down the the axle that might be the source of the smoke you saw rising?

 

[JeffL]

"Another question I have is , Is it likely that my head gasket was perfectly fine and I just removed it for no reason? Now it's just a matter of replacing the old one and finding out what the real problem is."

I think that was the point back in Post #2!
As stated above the smoke looks like it is coming from low on the tractor, below the starter.
I would clean it up put it back together; replacing all gaskets and then trouble shoot the issue. Wish I said that back in Post #2.

 

[Lzybmbjj30]

I've been watching this thread and I think it has somewhat gone off the tracks. It would have been better if more troubleshooting had taken place before the head was removed. To answer the original question, the head gasket in the pics was not blown.

Now that the head is back on using the old gasket, the first startup distributed whatever dust got in so the solution to that is changing the oil and filter and hope for the best. No point in taking it apart again until more tests are done.

What were the symptoms before the head was removed? Can't tell much from the video. Is the smoke from the vent tube or somewhere else?

There was a while back that I was mowing and only has water in the radiator. After moving for about 20 minutes it started to boil over and I had to shut the engine off.

After awhile I decided to fill the radiator with the 50/50 green ethylene glycol. The coolant overflow tank was bone dry as I was running it and not filled between the lines but the radiator was filled up to the cap.

I placed new exhaust manifold bolts on the engine but couldn't get all of them as some of the bolts were impossible to extract. I did actually tear part of the exhaust manifold gasket and I noticed the engine would smoke a lot during startup. I did buy a replacement gasket for that as well.


Ok so the mower runs for 20 minutes or so with the pto lever engaged. After awhile I start to get the smoke welling up until it's too much and I need to shut it off.

A neighbor of mine thought it might be a locked up fully attached to the blade assembly under the mower.

I did have the brake stuck and got it back to normal but the smoking still happens after 20 minutes.

 

[Ascott172]

So is it likely that your engine wasn't cracked or warped and all you had to do was replace the head gasket?

Another question I have is , Is it likely that my head gasket was perfectly fine and I just removed it for no reason? Now it's just a matter of replacing the old one and finding out what the real problem is.

I knew the head gasket was bad because after I replaced the themostat and mowed the yard coolant was bubbling in the reservoir. I checked the head with a straight edge and it was not warped.

 

[North Idaho Wolfman]

I placed new exhaust manifold bolts on the engine but couldn't get all of them as some of the bolts were impossible to extract. I did actually tear part of the exhaust manifold gasket and I noticed the engine would smoke a lot during startup. I did buy a replacement gasket for that as well.

Are you talking the studs that hold the manifold to the head or the bolts that hold the exhaust pipe/muffler to the manifold?

 

[Lzybmbjj30]

They are screw studs that exhaust manifold slides onto on the side of the engine. Before that a gasket is slid onto the studs. It looks like a muffler or maybe it is. I think there are 6 studs but a few of the broke off over the years.

 

[JeffL]

Ok so the mower runs for 20 minutes or so with the pto lever engaged. After awhile I start to get the smoke welling up until it's too much and I need to shut it off.

A neighbor of mine thought it might be a locked up fully attached to the blade assembly under the mower.

Have you looked at the mower deck? Any chance one of the spindles has a bad bearing? If bad they will get very hot and eventually lock up causing the belt to slip. All of the above will smoke.

 

[North Idaho Wolfman]

They are screw studs that exhaust manifold slides onto on the side of the engine. Before that a gasket is slid onto the studs. It looks like a muffler or maybe it is. I think there are 6 studs but a few of the broke off over the years.

Did you put thread sealer on the studs before you put them in?
The reason I say this is that on most of the kubota engines, those studs extend into the water jacket and if you don't put sealer on them they can leak water/antifreeze, thus smoke when heated up, thus cause loss of fluid and cause it to over heat!