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cylinder jug replacement

Rusty_Gold

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Looking to replace the cylinder jug off my 1975 K5, are all SOHC jugs interchangeable or do i need the exact year and submodel top match. Theres a bunch on eBay but only like two from 1975.
 
They can all be swapped just stick with the K cylinders. The earlier ones didn't use the extra rubber sleeves around the 8 cylinder stud holes but can be swapped. The F2 cylinders are something you want to stay away from because of oil return differences.
 
i got an offer for one thats been hot tanked and bead blasted with a fresh hone on it for $100 off a '72 so i might take it. You're talking about these right? IMG_1360.jpg do the earlier ones take regular Orings instead?
 
Yup those are what I am talking about. The early ones simply dont use anything around those holes. Honda did that in order to help "cure" head gasket seeps but the problem is actually weak head bolts that stretch thats why I dont do a 750 rebuild without using heavy duty studs...even on stock motors.

So now you are pulling the cylinder off? Not just a head gasket?
 
Ya I have to pull it, broke a bolt when I put the cylinder head back on so I have to take it to a machine shop or pick up a new one if they can't fix it
 
If it snapped on assembly then it will be easy to remove the broken bolt. Keep in mind when you remove the cylinder you will need to hone the existing block or the replacement block and use new piston rings. Anytime the pistons are removed from the cylinders you need to replace the rings.
 
If it snapped on assembly then it will be easy to remove the broken bolt. Keep in mind when you remove the cylinder you will need to hone the existing block or the replacement block and use new piston rings. Anytime the pistons are removed from the cylinders you need to replace the rings.

the new jug will be in this week and its been honed, do you know of good piston rings, i was just going to buy the ones on cyclex's site
 
ok good to know..... now i know you said the earlier models don't use anything around the holes unlike how the 75 used those thick gaskets. But now the guy i bought it from said ill need different orings for the oil seals between the head and the cylinder, is he wrong and i just use nothing? because i can't really find any info on k2/k3 model rings he's talking about

For reference heres the gasket kit i bought http://cognitomoto.com/collections/engine/products/honda-cb750k-69-76-complete-gasket-set
 
If you get an early cylinder there will physically be no place to put the very thick rubber seals. All you need are the two orings on the bottom of the cylinder between the cylinder and the case and the two on top between the cylinder and head...these are the oil pressure galleries to the top end. These orings are the same on all the sohc 750. Not sure what the guy was talking about. The picture of the gasket set show the ones you wont be using and only shows two of the orings you need. I would go to servicehonda.com and order 2 more of the orings just to be sure unless you have a Honda dealer close....they should have them as they are a common size.
 
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