MF 35 cast instead of Chrome liners

[MrNoo]

I have a 3 cyl MF35 that I believe has Chrome liners originally and heard it best to put cast ones back in as the lip is a lot smaller on the Chrome liners and tends to break allowing the liner to drop and hit the crank. Question is I know the lip area will need machining deeper but are the bores in the block the same with cast and Chrome or will it need boring out for the cast liners??
I am aware the Chrome liners are very thin and assume (rightly or wrongly?) that the cast liners would have a thicker wall, hence possibly need boring out of the block to fit them.
Also the 2nd oil control ring, or 5th ring right at the bottom of the skirt, do you fit these or not on the 3 cylinder engines, I know it is common to omit this ring on the 23C engined 35's as they say that is where all the bore wear stems from.

 

[Ley253]

I have asked my local massy man about this and he is of the opinion that the liners are identical, with the exception of the material. You must fit cast rings in chrome liners, while chrome top rings can be used in cast.
I have a liner puller/replacer for the 135 engine you can borrow if you like.

 

[MrNoo]

Many thanks, I have done further research and the bore OD of the liners is the same, the lip is just deeper on the cast ones and hence they are less susceptible to dropping the liner down the bore, so I have ordered a set. The trick is to run a few beads of weld down the old liner and it'll then come out, new ones get put in the freezer overnight and apparently they slip straight in. They do use the 5th ring in these 3 pot Perkins engines, they dont in the 23C engine. Looks a very simple engine to work on compared to the 23c engine and the TEF engine, parts are a lot cheaper to. On the whole it's not in bad nick (got it back to the yard this morning) so will get and strip it down this afternoon and see where we're at!
Many thanks for the offer but I am hoping I should be ok.

 

[Ley253]

I wouldnt touch the old liners with a welder, so easy to go straight through and weld liner to block, or pit the block. You can chip them out with an old screwdriver.When refitting, bore in block must be clean, not even a thread from the cleaning rag should be there, plenty of oil on the liner od and block, and once started keep going, if you stop half way the liner may jam!
For myself, I would not use any method other than a puller/repacer thats why I made one!
Rear crank seal should be asbestos rope, what you seem to get now is two lumps of white plastic, be very careful on fitting them!
I fail to see how the lip can be different, if the block is the same( which I am assured it is)

 

[MrNoo]

It's just the depth of the lip that differs, 1.5mm versus 3.something mm. I'll get it apart first and see how it looks.

 

[REStracTORATION]

Yes you are correct I've changed a few over the years to cast liners
The bore is identical and just the lip needs adjusting.
While the block is there get them to true it and use semi finished liners as fully finished ones aren't really as round as they should be.
Hope this helps
James