Lehman 120 Head

[BruceK]

Can anyone please help with the head stud tension, and the tightening sequence, for the L120 engine?

 

[Peter B]

Can anyone please help with the head stud tension, and the tightening sequence, for the L120 engine?

My manual is down at the boat Bruce, but I'll be down there tomorrow am. Guess what. Someone is going to look at it. I doubt they'll buy it tho, but hey, I was going down to check on it anyway. He is in North Qld, and would want aircon. Somehow I don't see that as feasible in my boat - not impossible, but it would cost a lot. Apart from the installation, it would need huge addition to the power supply/generation/battery storage situation.

I'll look up the manual for you while there, and snap it with my scan app, and email it to you. Someone else might beat me to it, but never mind.
How come you need it. Are you taking/had to have the head off for some reason..? Rebuild..?

 

[Busterbrown]

I have the 2714 and torqued the head bolts 115 pounds. I also ran a tap on block to clean threads and lightly oiled the threads before assembly.

 

[Shoalwaters]

It certainly "feels right" to lightly lube such threads before reinstallation, but is it the right thing to do?

 

[psneeld]

lubing threads usually require different torque values.


I believe Ski or another resident engine guy once posted that it is very hard to get engine blocks totally dry of oil anyway....we'll see if anyone agrees.

 

[Mule]

What about never seize compound?

 

[Ski in NC]

No to neverseize. Designers assume a certain lube and that determines the coefficient of friction. Change that and you change the clamping force. Too slippery and you will yield or break bolts.

The manual should state what lube to use. Most are just clean bolts and engine oil, some specify other things like moly lube on 3208's.

If the manual states to use neverseize, then do. Otherwise, no.

 

[Mule]

Thanks Ski.

 

[meridian]

Here is a write-up I had in my files that also covers valve setting. There is also a STICKY with excellent information.
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[psneeld]

Terry...is there a download able site or link for those pages?

Haven't seen them and my manual isn't quite as helpful.

Thank you!

 

[meridian]

You can click on each page, open it up, copy, then past to something like WORD

 

[psneeld]

You can click on each page, open it up, copy, then past to something like WORD

Thanks...I tried a couple things...the thumbnails were of low enough def that they blow up fuzzy.
I will try on my laptop and word, etc...later...thank you...

 

[meridian]

If that doesn't work I can email you the PDF,s

 

[psneeld]

If that doesn't work I can email you the PDF,s

Thanks...they are good enough after playing around with them...