Hello all,

Have a question for you all since I have heard answers on both sides. I bought an F22c out of an 2005 that had been over heated for $350 (came with all engine accessories so I figured why not) and once I pulled off the head this is the damage I found.




Now the question that I have is can that damaged head be taken to a machine shop and welded (built up) and then machined down? After inspecting the entire head that is the only damage I can find (no cracks, etc.) so I figure if that can be salvaged it might be worth a shot.

Also, assuming there is no physical damage to the crank/rods would there be an issue with reusing those parts with the heat stress they were exposed to?

 

IMO... id get a new head. With damage like that I wouldn't even want to use the internals.. but that's just me. Billman is a good person to ask on this...

 

I can't imagine using that head. Some of the other internals may be fine. Just take them to a machine shop and have the critical dimensions inspected to ensure they're within their service limits and that there's no damage. That damage looks like something something else might have been involved, but I can't be sure. Just have things inspected/measured to be sure.

It really depends on your goals. Do you want a basic back to OEM-like build, then what I described would just be fine (even if, say 1 piston was bad and you replaced just that 1). If your goals are more ambitious then you're going to be more conservative with what you consider to re-use.

I would suspect (though measure & inspect) that the crank is likely still good. There's $900 you don't need to pitch.

 

Awesome! That's kind of what I figured as far as the head goes... And this engine is kind of just a side project, I have a fully functional F20c in my AP1 still. Thanks for the replies so far!

 

About 10 years ago, I bought a Nissan Pick-up for $200 that had that same type of damage. The head gasket had blown and they continued to drive it. Every time the cylinders (with the bad gasket between them) fired, it shot a hot jet of combusting fuel into the adjacent cylinder.
It melted a channel into the head exactly like that. The block was damaged in the same way. I am very surprised your block is not damaged also. If you reuse the block, I would have it decked.

 

There is damage in the correlating cylinder, it would have the be re-sleeved and have new pistons... Just got the oil pan off last night so I haven't seen the extent of the damage (if any) to the bottom end.

 

Might beable to hone the cylinder, but you would have to find a shop capable of honing the FRM material that coats the cylinder walls in our engines.

 

I've repaired heads with that type of damage before. A specialised head repair shop who knows what they are doing to weld up and resurface the head. Of more concern is how hot the head got as it would have burnt up all the water through that leak. If its got really hot the head would have lost its heat treatment and gone soft, and could also have warped. If the warp is bad enough it can put the rocker assembly/camshaft journals out of alignment.

I would check if the head is straight, if it is then get a specialist head shop to check the hardness. If these two points are OK then get it welded and resurfaced.

I'm pretty sure the block will also need resurfacing as the corresponding area to the damage on the head would have heated up and is likely to have shrunk back.

 

I had a machining biz back in the day and I would attempt the repair. However...

With the amount of perfect cylinder heads avail on s2ki, I would sooner just pick up a nice used unit. If you cant find one I'll point up in the right direction.