Damaged Liner???

[balmoralbob]

Hi, have posted previously about our Perkins engine re build and the trauma involved with stripping gearbox/head and in fact every part associated with stripping for a re build. As this is all taking place on board it is to say the least very difficult. Having spent 3 weeks removing one seized piston after drilling it out till it would move, have now found 3 very small chips in liner caused no doubt by my aggressive style of piston removal. My question is: because of difficulty removing liner in place, is this damage sufficient to warrant removal? Also as liners are dry type and are either parallel or flanged, the problem arises that if they are parallel, these need machining after fitment which is impossible where we are. The flanged type which am pretty certain they are, requires no machining and accepts stock piston and rings. Any idea's on the way to go? Am pretty certain liner will have to go but would love to avoid it if possible. Have attached pics of bore
Cheer's
Steve

 

[Mark Maulden]

What's ur short/long term objective? If u want to leave the liners in place I think you'll have to address those anomalies in the liner as I see material that sticks out and would cause ring breakage. If u can address it, it would end up burning some oil and have some compression loss. All liners I see don't very good. They would all need to be honed at a minimum and u would have to find a way to keep honings from dropping through. I also see some serious cooling passage restrictions. So, again what is the objective for the engine and boat?

 

[balmoralbob]

Hi mate thanks for fast reply, long term is this engine is staying, motor ran fine until manifold let go and seized on that piston, rest of liners show no sign of wear, all pics are of same cylinder. Intend to flush gunk from water passages and get running again
Steve

 

[KD3PC]

an old fashioned hone, should get you "service" out of the liner for a bit, until you can get it replaced - which is the desired solution.

First you need to confirm which of the several possible liners your Perkins has. I don't see the flange or lip in your pics, so.... Ideally liners should be done in a machine shop/clean space at least.

That being said, I have done them in the plowed fields or on construction sites, but I am Not sure what your limitations are, but liners are used for situations like yours...out in the field service. You do need to make sure that the debris is totally removed, or it will end up in places more difficult to clean up.

Similarly you will likely need to drop the pan, create a sleeve puller or weld pull points in to the existing sleeves. Depending on which Perkins you have, you may be able to use a small bottle jack to "push" the liners out.

Sleeves are related to the serial number range and model of perkins, so you will need info.

Best of luck on this, it will be a learning experience, for sure.

 

[kloudie1]

I can't tell how far down the sleeve the nicks are, but if they are at the bottom in a place where the rings don't touch, just a smoothing is all that is needed.. If the nicks are about where the piston reverses direction at BDC, there will be no loss of performance and again, smoothing so a ring does not catch is the only thing necessary. The higher the nicks, the more critical they become .. They look to be below mid-stroke??