I left it at this stage waiting on a piston, I gave it a touch more to make sure any moisture haze would be eliminated right before I dropped the piston. I wonder how much of a ring gap one would have to be wore out, I think min. compression is about 330 lb. I think spec is 416 to 469 new. I'm still over 400 on the other 2 cyl.
Beware of aftermarket pistons
- Thread starter Muggman
- Start date
I fired up the d722 today. It ran good, no smoke out exhaust and none out of the crankcase vent. When I acquired it leaked everywhere and ran on 2 cyl. And smoked out the crankcase vent. Someone has finger freaked the idle adjustment and maybe even the governor spring to compensate. I only let it run a short time. I checked everything and noticed the head gasket is leaking water. I didn't like the new headgasket but tried it anyway. SO, I'm back to pulling the head back off. I may just buy a kubota head gasket this time around. The head and block looked good and I checked the valves, I may have head surface checked this time. To many unknowns.
You have a straight edge, and some feeler guages? Pretty easy to check for warpage.
I'm not familiar with the style head gasket that came in gasket kit. (Aftermarket) The new gasket was a laminated metal thing with a black coating. It may seal if it was gotten hot enough, I don't know. I would have rather had gasket with some fiber composite coating.
Multi layer steel gaskets are pretty common anymore, the old graphite style seems to be going the way of the dodo bird. Can't comment on what kubota supplies. Last one I rebuilt was pretty much all aftermarket.
Last engine I worked on was a 5.7 hemi and it was multilayer steel buti used Mopar or felpro gaskets. If you work on newer model cars you better use factory oem sensors period. And try to use oem lifters rings and such if the price ain't over 50% more. Seen alot of new aftermarket sensors cause problems. The head gasket might have been my fault but them composite gaskets are a little more forgiving. Alot of old school dragster builders still put the metal gaskets on them small block Chevrolet if the running iron heads, but that's about over with too. I'm going to buy a graphite 1 to go back with. I did put the oring on the oil tube because the gasket had the big cutout. I know people ask whether 2 use it or not, I have seen gaskets that look like a sealing ring built in. I got the fuel and oil leaks stopped. I got the front pinion leak stopped. Still got the hydraulic leaks to go. No one would have fixed this tractor but me. It should have been parted out but I'm hard headed. If the had gasket would have sealed I would have been sheeting in high cotton.
Pretty sure you only need the oring if there's a cut out for it. Haven't actually seen one without the cut out though. Can't imagine why you would use one.
I can't find any clear info on the oring. I'm not a kubota person. This is my first. The block and head have no groove but the headgasket has a hole about the size of a dime.and the pin is about 1/4 inch. The oring isn't very thick so I figured it will flatten to the head gasket thickness. I see what the oring looks like when I pull the head again.
I see you have some cub cadets. I have 2 cub cyclops I want to part with, I have a post in sell and trade.
Thanks for the offer, were a bit far apart though. I'm actually in the process of getting rid of most of my cub collection. Only planning on keeping the 582 and possibly the 782. The 582 will be for sentimental reasons and partially because it has a cat 0 3 point and I have a lot of cat 0 attachments. The 782 I just rebuilt and swapped a m18 into. Truthfully the yanmar is twice the lawn mower the cubs are but parts are a pain to get for it.
