Log Splitter Engine Damaged???

[KenLockett]

Hey guys went to change spark plug in my TSC Huskee Log Splitter. I put in what I though was a equivalent replacement and the thread depth was longer than what I took out but threaded in no problem although went farther in than original. Tried to start and felt like a lot less compression and made a whirring sound when I pulled. After repeated pulls even had a pop. Thought maybe plug wasn't in all the way but it was. Took it out and electrode was bent over. looked inside and could see piston moving in and out as I pulled starter and no obvious damage when looking inside with flashlight. Put original plug back in and same thing. Did I screw something up? Didn't force the plug in and screwed all the way in although certainly deeper than original. Any ideas? Made video with sound but cant upload .mov files.

 

[Ashful]

Hey guys went to change spark plug in my TSC Huskee Log Splitter. I put in what I though was a equivalent replacement and the thread depth was longer than what I took out but threaded in no problem although went farther in than original. Tried to start and felt like a lot less compression and made a whirring sound when I pulled. After repeated pulls even had a pop. Thought maybe plug wasn't in all the way but it was. Took it out and electrode was bent over. looked inside and could see piston moving in and out as I pulled starter and no obvious damage when looking inside with flashlight. Put original plug back in and same thing. Did I screw something up? Didn't force the plug in and screwed all the way in although certainly deeper than original. Any ideas? Made video with sound but cant upload .mov files.

Bent over electrode... you know what happened there. But no obvious damage to piston and the fact that the rod ain't broken has me scratching my head on the loss of compression, esp. when the original plug is re-installed. You would think that you'd have felt something unmistakable while pulling it over, if you had damaged the head or connecting rod.

Was this splitter run with no issues before changing the plug? How recently? Any chance there's an issue with the recoil starter, which is compounding the confusion?

 

[brenndatomu]

Probably bent a valve. Not an expensive part...but the labor could add up a bit unless you can DIY.
You can verify if the valve is bent by removing the valve cover and checking the valve clearance, the bent one will have way too much clearance.

 

[DodgyNomad]

As mentioned above, check to see if you have a valve stuck open for any reason. That would explain the loss of compression.

 

[johneh]

Do a compression test . Top of piston my
be cracked even though you can not see it
If there is no compression remove cyl. head
and check top of piston .

 

[KenLockett]

Yeah ran it like a week ago and it started right up. I guess it could be the starter recoil. Never have taken a valve cover off but guess I could give it a try. Anything difficult I should be aware of?

 

[Ashful]

Probably bent a valve. Not an expensive part...but the labor could add up a bit unless you can DIY.
You can verify if the valve is bent by removing the valve cover and checking the valve clearance, the bent one will have way too much clearance.

If like any other TSC (Speeco) log splitter, this has a Briggs 675, or other similar flathead engine. I don’t see any way to bend a valve on a flathead, by installing the wrong spark plug. This ain’t your dual-overhead cam rice burner.

Also, there are no “valve covers” on flatheads, you would have to pull the head to see the valve, which I don’t recommend. You would want to pull the breather cover to see the valve action, if you think they’re sticking, which is always an (unrelated) possibility.

 

[VirginiaIron]

Maybe a stuck valve is a coincidence, unless something broke off the plug and is now holding the valve open.

You should have felt the piston hit the plug. If it was hard enough you could damage the piston with hole or crack but you should see that through the opening.

"... Put original plug back in and same thing..." Bent electrode?

Maybe you broke the shear pin on the flywheel and the engine is no longer in timing.

If you have no compression due to rings or crack, put a tablespoon of engine oil down the hole and spin the crank over several times, then install the plug and see if compression is restored.

Keep us posted.

 

[greg13]

Possible cracked head or plug threads stripped from the plug being pushed by the piston. You should pull the head just to get a good look.

 

[Ashful]

Maybe... something broke off the plug and is now holding the valve open.

Based on the information we have, this seems to be the most likely scenario. Pulling the head is the only way to know for sure.

Buy a new head gasket, and re-torque to 140 in-lb when done. Yes, that’s from memory, I’ve owned a few Briggs 675’s.

 

[Ashful]

Possible cracked head or plug threads stripped from the plug being pushed by the piston. You should pull the head just to get a good look.

But he didn’t indicate any problem torquing the old plug back in. We are missing something, here.

A photo of both plugs would help. Show damage on new plug, is there any missing ceramic?

 

[maple1]

Every once in a while a thread comes along that makes you want to be able to pop thru your computer screen so you can be there & see something for yourself. This would be one of those.

 

[KenLockett]

Guys more video and photos to follow.

 

[jetsam]

It could be that the engine was sitting in the middle of the intake stroke when the new plug was installed, and that it actually managed to fire before it smashed the electrode down. Then if the piston couldn't come up to the top so the cam could roll over into the power stroke, badness ensues. I'd guess bent rod on that one.

On the flip side, it could be that the engine was at the exact top of a stroke when the plug was installed, and the electrode was bent over by the act of installing the plug until it hit the piston. In that case the engine might be fine...

 

[KenLockett]

Guys see attached photos. As you can see the wrong plug is substantially longer than the correct plug and the electrode is squashed. Also took photo looking into the cylinder. The piston looks offset. Not sure if this is by design or not. What I notice is that for every two revolutions of the flywheel the piston moves forward then starts to retract immediately at beginning of third revolution and so on. You can see on the cylinder where the plug contact made contact. Verified I was getting spark then put everything back together. Will just not fire and feels differently I think. Ever so often after enough pulls a pop sound that I suspect if fuel trying to ignite. The plug is wet if I take it out. Think I messed up. Any further suggestions short of taking the head cover off and trying to repair, set timing, etc.? My heart is not really in it to be honest. If something bent or damaged is taking it to a small engine repair shop going to cost me more than a new engine at $297 prime on amazon for same engine or less than $200 for harbor freight predator although not sure a direct replacement. Figure putting new engine on is relatively painless and easier than trying to break this one apart and repairing that I have never done.

I should have just left it alone. Can't believe I didn't compare plugs before putting the new one in. Let me know what you guys suggest. Thanks.

 

[KenLockett]

It could be that the engine was sitting in the middle of the intake stroke when the new plug was installed, and that it actually managed to fire before it smashed the electrode down. Then if the piston couldn't come up to the top so the cam could roll over into the power stroke, badness ensues. I'd guess bent rod on that one.

On the flip side, it could be that the engine was at the exact top of a stroke when the plug was installed, and the electrode was bent over by the act of installing the plug until it hit the piston. In that case the engine might be fine...

Remember once I installed the plug I tried to start it a number of times. It would have been ramming the plug on each stroke right?

 

[Highbeam]

Was it running with the old plug before you decided it needed fixing? Like the same day? Could be anything from bad fuel to failure to hook up the plug wire right.

Compression, fuel, spark.

The oem engine isn’t exactly built like a tank but a flathead engine is also pretty forgiving.

 

[brenndatomu]

Oh holy cow, that plug is A LOT longer than the old one! The chance it has the piston damaged is pretty good IMO.
So what make/model engine is on this thing anyways?

 

[maple1]

Should be pretty easy to check compression.

 

[DodgyNomad]

Long plug for sure. Pop the head off and check the damage. Not a hard job, best way to take inventory of what you're working with.

 

[Ashful]

Oh holy cow, that plug is A LOT longer than the old one! The chance it has the piston damaged is pretty good IMO.
So what make/model engine is on this thing anyways?

It's a Briggs 675 series. You can tell from the pic of the head, not to mention that's the primary motor used on 22-ton Huskee splitters.

Given the way the electrode is bent, twisted to the side rather than just smashed straight down, it seems most likely it was bent during installation rather than during a piston stroke. This really reduces the likelihood of piston damage.

 

[brenndatomu]

If like any other TSC (Speeco) log splitter, this has a Briggs 675, or other similar flathead engine. I don’t see any way to bend a valve on a flathead, by installing the wrong spark plug. This ain’t your dual-overhead cam rice burner.

Also, there are no “valve covers” on flatheads, you would have to pull the head to see the valve, which I don’t recommend. You would want to pull the breather cover to see the valve action, if you think they’re sticking, which is always an (unrelated) possibility.

It's a Briggs 675 series. You can tell from the pic of the head, not to mention that's the primary motor used on 22-ton Huskee splitters.

Given the way the electrode is bent, twisted to the side rather than just smashed straight down, it seems most likely it was bent during installation rather than during a piston stroke. This really reduces the likelihood of piston damage.

OK, so we have established you are very familiar with the BS 675...which the OP still has not verified that this is actually his model...but if it is a 675, then yes, I agree that its probably not very likely a valve got bent. And I will also agree that it is not likely that the new plug punched a hole straight through the piston without the OP ever feeling or hearing anything really strange. But I did say "piston damage", which grinding the electrode into the piston while it is at TDC (if that's how things went down) "piston damage" very likely occurred. (unless the plug is not actually located over top the piston?) Maybe piston metal shavings fell onto the cylinder wall, or in/on rings...or maybe a nice chunk of aluminum from the piston was carved out and bounced over into one of the valves, holding it open...heck even just some carbon buildup knocked loose could do that same things as actual metal.
A simple compression test, or even better (but less likely the average Joe has the tools to do) a leakdown test, would tell us a lot here. If no gauges are available, then just pop the head off...I would think it could be done in a couple minutes, even less if there are no "auxiliary items" or sheet metal in the way. The closeup pic of the sparkplug shows 3 of the bolts holding the head on...there are 5 more just like that...really not much to taking the head off for a quick looky look.

 

[brenndatomu]

(unless the plug is not actually located over top the piston?)

Thinking about this a bit more, it looks to me like the plug is actually located in the space between the piston and the 2 valves...is it possible the plug is actually over top the edge of one or both of the valves...with one of them hanging open when the plug was screwed in it would have wiped that side electrode to the side like that...then bent the valve, either upon plug install, or when the engine was turned over. IDK, whatever we are looking at in that "down the spark plug hole" pic looks to have a nick in it...

 

[maple1]

Ya - I think that's a valve we're seeing in the plug hole, and not the piston.

What I notice is that for every two revolutions of the flywheel the piston moves forward then starts to retract immediately at beginning of third revolution and so on.

That doesn't sound like piston action.

I'm calling bent valve - it's stuck open in the pic..

 

[KenLockett]

Was it running with the old plug before you decided it needed fixing? Like the same day? Could be anything from bad fuel to failure to hook up the plug wire right.

Compression, fuel, spark.

The oem engine isn’t exactly built like a tank but a flathead engine is also pretty forgiving.

Yes it was running great the week before. Started in first pull last time I ran it. Bought the plug over the winter intending to change it in the spring. Finally got around to it.

What I haven’t checked is actual compression using a gauge. Drained fuel and put new fuel in as well. No difference. Just will not fire.