Torquing Head Bolts and Adjusting the Valves

[Despacio]

Time for a new project. I now have 2900 hours on the Ford Lehman 120, which I suspect will be running for quite a while longer

I believe I have done all maintenance (I hope) and the thing runs perfectly. But, I have no idea when the head was last torqued, and the valves adjusted, and maybe it's time.

Anyone done this? What is the level of difficulty? How often, in the real world, is it done?

Knowing my limitations, I could (probably) do it, but might benefit from watching someone else do it.

[jleonard]

Easy job. I did mine once at around 3400 hours when I first bought the boat. Everything was good, maybe one loose rocker arm.
The procedure for both is in the operators manual. You don't need the barring tool, you can "tick" the engine over while holding down the stop button to get the valves "rocking" to do the adjustment.
If the engine is around 140 F that is hot enough.
You can buy the gasket at ADC. They should have plenty of them in stock. (I hope so because I have to order one as my gasket is leaking now.)

[meridian]

I agree, easy job. Just be sure to wear heavy gloves when backing off the head bolts, I got some bloody knuckles. I did mine one at a time. I back off about 1/2 turn, then sweep the torque wrench to the proper setting.

[Despacio]

Completed the job, and it was pretty easy. The suggestion of wearing gloves was a good one.

Thanks!

[mike66]

How did you turn over the motor while adjusting the valves? And, do you think the head bolts needed the re-torquing? Do you feel like you changed anything from where it already was? Third year of ownership of a boat without a maintenance log and 7,000+ hrs, I feel like it would be prudent to do these things as well as send the injectors out for service. Thoughts???

[meridian]

Bob Smith, ADC, recommends re-torqueing the head prior to a valve adjustment every 1,000 hrs.

[Despacio]

Reading the manual, it seemed to be a two man job, one bumping the starter, while the other was holding the kill rod on the injectors while watching the valves, and, not having a torque wrench, I took the easy way and asked the local yard mechanic to help me after work.

I removed the valve cover, but mostly the wrenching was done by Carlos. He backed each head bolt off 1/2 turn then torqued it. Nothing was very far off if anything. He brought a new valve cover gasket but we didn't need it.

The valves didn't appear to need adjusting either. All in all I probably could have gone another 1000 hours.

[mike66]

I suppose if I remove the injectors first, then turning the engine with a wrench on the flywheel bolt wouldn't be that hard.
Terry - I hope to take Bob's course in FL this winter. Guess I can wait till spring to go over my engine. Thanks for the advice.

[jleonard]

Bob Smith, ADC, recommends re-torqueing the head prior to a valve adjustment every 1,000 hrs.

To me that is excessive. I'd bet less than 1% of owners adhere to that schedule.
I have "read" that sometime around 4000 hours would be the time to think about getting injectors rebuilt.

[mike66]

Since I'm at near twice that with no history, guess it's time to do the injectors. I'm beginning to have a little roughness in the idle; Peter Compton says in his book it's most likely injectors if the rest of the fuel system looks okay. Can't hurt much except my wallet to get them done. With all your travels, J, have you adjusted your valve clearance on a regular schedule?

[jleonard]

With all your travels, J, have you adjusted your valve clearance on a regular schedule?

No. I did it once when I first got the boat and it's been close to 1000 hours now. I DO have to replace the valve cover gasket as it is leaking a bit, so I probably will re-torque the head bolts and then I will be forced to adjust the valves.
If not for the re-torqueing I would not bother adjusting valves again until I hear a loose one.

[mike66]

Thanks for that reply. My ear isn't tuned to diesels; this is the first one I've owned, so all the clatter and noise doesn't tell me much. I'll just order up a valve cover gasket and check them to be safe. Another learning experience.

[meridian]

You don't need to remove the injectors to turn it over by hand. I did it with a 12" socket handle.

[jleonard]

My ear isn't tuned to diesels; this is the first one I've owned, so all the clatter and noise doesn't tell me much.

Eventually you will be tuned into the various noises. It takes time.

[RobS]

My ear isn't tuned to diesels; this is the first one I've owned, so all the clatter and noise doesn't tell me much.

Eventually you will be tuned into the various noises. It takes time.

You could always just buy a Yanmar, they just go BANG when there is a valve issue, you'd surely hear that!