Cracked head, but not what you think

[Gerald]

From what I can make out from the manual, parts book, and pictures on the internet there looks to be a single gallery sending oil to the head. From the look of it the gallery sits at the rear on the left hand side of the engine and my crack is on the rear at the right so hopefully the crack doesn't go to a gallery. Hopefully someone who has had an engine apart can chime in with a definite answer on this one.

Oil pressure sender is at back of the block, about in the middle, trying to remember how cams get their oil.

 

[TURBO200R4]

i am going to take a guess
if it starts to leak in the first two minutes then it is probably an oil circuit
if it takes an hour probably not

 

[IFIXSHlT]

Give these guys a call. I was actually considering using them when I was thinking of repairing the head. Then fourth gear went, and I just swapped engines.

“

 

[Jhortz]

i am going to take a guess
if it starts to leak in the first two minutes then it is probably an oil circuit
if it takes an hour probably not

1 million percent correct. I've given it a clean and rode it, and ended up with a pool of oil in the corner which is a bit concerning. But I do need to properly clean the whole area and run the bike while watching the crack to see exactly what I am dealing with here.

I've dealt with similar issues in my work hundreds of times before, but I wasn't paying for the repair so the solution looked different . When I say that I mean I was dealing with engines with ready to go rebuilt components so it is completely unnecessary to repair cracks (for example the head would come off, a rebuilt one would be fitted, and the cracked used as a core for the next rebuild), not to mention the cost of lost time in industry which isn't really a problem I face (other than going nuts because I want to ride my bike). I imagine worst case will be head off and send it to a head shop, but the bike also has a questionable transmission which I will be looking at. It might ultimately be better to buy a second hand engine.

 

[Jhortz]

For those following the saga, here's a quick update.

Turns out the head has been cracked for a while, once I started digging in I found some traces of old clear silsatic so someone has previously tried to seal the leak. I've owned the bike about two years and there has always been a tiny wet patch there but I didn't think much of it as I assumed it was the rocker cover gasket starting to leak.
Oil starts to visibly ooze out of the crack after about 1 minute of running, it looks like it is pressure feed but I'm still not sure. I can't see any oil galleries anywhere near the leak so figure it is either a very long crack that has traveled very far into a gallery and is being pressure feed, or the crack is opening up as it grows and it is actually a large gap which is letting oil which accumulates in the head flow out at a decent rate so it looks pressure feed.
The plan is to remove the head and work out exactly what I'm dealing with here. There is a decent head shop in town so I will see if it is repairable, I imagine it will be but also have concerns that I'm seeing the tip of the iceberg here and that the crack is enormous. If it can't be fixed the plan is to panic, and then probably source a replacement head if possible. So if anyone has a lead on a second hand head I'd love to hear from you.

 

[Gerald]

For those following the saga, here's a quick update.

Turns out the head has been cracked for a while, once I started digging in I found some traces of old clear silsatic so someone has previously tried to seal the leak. I've owned the bike about two years and there has always been a tiny wet patch there but I didn't think much of it as I assumed it was the rocker cover gasket starting to leak.
Oil starts to visibly ooze out of the crack after about 1 minute of running, it looks like it is pressure feed but I'm still not sure. I can't see any oil galleries anywhere near the leak so figure it is either a very long crack that has traveled very far into a gallery and is being pressure feed, or the crack is opening up as it grows and it is actually a large gap which is letting oil which accumulates in the head flow out at a decent rate so it looks pressure feed.
The plan is to remove the head and work out exactly what I'm dealing with here. There is a decent head shop in town so I will see if it is repairable, I imagine it will be but also have concerns that I'm seeing the tip of the iceberg here and that the crack is enormous. If it can't be fixed the plan is to panic, and then probably source a replacement head if possible. So if anyone has a lead on a second hand head I'd love to hear from you.

Hate to hear that, sorry for your misfortune.

 

[Jhortz]

Hate to hear that, sorry for your misfortune.

Cheers, the amount of misfortune will depend on if the head can be repaired or not. If they can weld it up it's not the end of the world, if I need to find a replacement head I will be in for a serious drama though.

 

[Tripps]

If you need one, try Pinwall, they've always come through for me

 

[Jhortz]

Just a quick update to those following.

The head is off and the crack is not repairable. It could be welded from the outside which would stop the leak but the crack would continue to grow and would eventually break back through. The inside of the crack is absolutely inaccessible, I thought it might have been leaking oil out that was gathering in the top of the head above the bucket, but it isn't. It is cracked right at the bottom well below the where the bucket runs. You can't actually even see it but it is right down where the bottom of where the valve spring sits on the head, there is no way you could ever get in there to weld. The oil was oozing out after about 30 seconds, it looked for all money to be pressure feed, but there are no galleries anywhere near it, it was just a wide crack that was allowing oil to flow.

The good(ish) news is that I have found a good second hand head for $1200AUD. So I should come out of this things with my shirt still on my back.

 

[Gerald]

Just a quick update to those following.

The head is off and the crack is not repairable. It could be welded from the outside which would stop the leak but the crack would continue to grow and would eventually break back through. The inside of the crack is absolutely inaccessible, I thought it might have been leaking oil out that was gathering in the top of the head above the bucket, but it isn't. It is cracked right at the bottom well below the where the bucket runs. You can't actually even see it but it is right down where the bottom of where the valve spring sits on the head, there is no way you could ever get in there to weld. The oil was oozing out after about 30 seconds, it looked for all money to be pressure feed, but there are no galleries anywhere near it, it was just a wide crack that was allowing oil to flow.

The good(ish) news is that I have found a good second hand head for $1200AUD. So I should come out of this things with my shirt still on my back.

sorry for your misfortune