4tnv98 questions about internals and head damage

GrandpaSmurf825 · Wednesday at 7:23 PM

I don't think I would mess with the ridge in the cylinders unless you are pulling the pistons and I didn't see where you said that.
If you are getting a different head I would still look it over well. If it's coming complete you are relying on someone you don't know unless it's new.

As a sidebar. When you torque bolts you are stretching them. For instance on a John Deere 6068 you go in 3 steps if I remember correctly. They want the threads lubed with oil also. You go through two stages of torque settings. Then you "clock" them. I don't recall now how far they have you go but you turn from for example 12 o'clock to 3 o'clock to finish the process. They have determined that is stretching the bolt to a specific amount. I have also been involved in "torquing" engine bolts where the method required them to be measured to determine when they were at the correct torque. There was a gauge that was attached that determined when the torque value was reached. That was on a General Electric locomotive engine.

franka02809 · Wednesday at 7:53 PM

Ok sounds good I’m not pulling the pistons. I ordered a new head from fridayparts with the valves in it. I am finding the bolts are not torque to yield so I can reuse them. I do have a pic from the manual that shows the torque specs and process. I had to use that to remove the bolts in the same order. They do half torque first the final. I do have a gasket kit for the engine so I can install all new on the head, intake, exhaust etc. looks like the granite I got is 12x9x2 and the paper is 11x9 so there will be some non sandpaper edges it seems and I guess that’s ok. I just ordered the Dykem steel blue also. Getting close to done, thanks again for all the help.

mrmikey · 2025-12-11T06:25:55-0500

Just for info.
There's a young fella I watch on YT, 2vintage he buys old bikes mostly and rebuilds them, not a mechanic by any stretch but a pretty smart fella.
He had bought a Kubota RTV900 with a bad diesel engine, ends up the head was cracked so he bought a new one off EBay. Long story short it was the correct head but the wire the valve springs was made from was too big a diameter. It ended up breaking a rocker arm when he got it going as there wasn't enough space to compress the valve with the too big diameter wire. Just something to keep in mind to check when you get the head.