Lehman 120 valve clearance

After numerous searches of this and all the usual forums and websites......

Plus looking though several manuals for Ford Lehmans, Sabers, generic Lehman manuals.....

I am more confused than ever due to conflicting numbers and whether engine warm or cold.

I think last time I adjusted them it was 0.12 exhaust/0.15 intake with the engine warm.

Who has an idea and what was the source? ...please.....

..I know call American Diesel....

valve clearance

American Diesel will tell you to set to those specs cold - for the FL 120. Explanation is that the FL135 head is exactly the same and the manual for it specifies cold.
That is what Bob Smith advised in his class.
Certainly a lot easier cold.....

Dan

Lehman 120 model 6D380 380ci 6 cyl
Valve clearance HOT Int. .015" Exh .012"
From the Lehman Operator's manual and parts identification 4C61-B May 1976

From the Ford of England shop manual for the 2700 Range 4 and 6 cylinder diesel engines (base engine for the FL120).

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30. Adjust the valve clearances. The clearances must initially be set with the engine cold to give a gap of 0.014 to 0.018 inch inlet and 0.010 to0.014 inch exhaust. [This is after a reassembly]

NOTE- The clearance should again be checked and readjusted if necessary when the engine is at its normal operating temperature. (See General Specifications)
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General Specifications says.....

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Valve Clearance (cold) inlet.... 0.014 to 0.018 inch
Valve Clearance (cold) exhaust.... 0.010 to 0.014 inch
Valve Clearance (hot) inlet....0.015 inch
Valve Clearance (hot) exhaust... 0.012 inch
---------------------------------------

The folks we know in England with a lot of experience with these engines in vehicle, industrial and agricultural service told me they always adjusted the valves hot other than the first time after an overhaul. This may be easier to do in a dry land application than down in the engine space of a boat......

Set them cold to the 12 and 15 spec. just don't set them a really tight 12 or a tight 15. They will be fine. It will always be slightly more gap and when hot you should still be within the range. These engines are pretty forgiving. If you where setting heights on a cat injector -- well that would be another story.

See, just a few posts and all over the place.

The PO was convinced the motor in the boat was 135 and when I left to bringbhervhome, setvthevvalvdsvaccordingly.

Later that year American Diesel and I figured out that I owned 120, not a 135. They said good that the valves were set to 0.15 as that was better than a 135 being set to the 0.12 exhaust. So they did advise me the 2 engines were different.

So it sounds reasonable that I set 0.12 exhaust and 0.15 intake at any temp and I will probably make Florida and back yet again.

Thanks everyone

Simplest is the go - no go method.

If you need .12 ,,, a .11 should slide by easily and a .13 a hard fit.

A machinist would say a "light drag" fit at .12 , but opinions vary as to what it feels like.

Too tight can cause damage with the valve not being seated long enough to cool.

Always check running hot with the .11, just to be sure the valve is not too tight.

I think last time I adjusted them it was 0.12 exhaust/0.15 intake with the engine warm.

Who has an idea and what was the source? ...please.....

Click to expand...

That's what is in my manual but hot.
When I did mine 1000 hours ago the engine was warm to the touch. (Probably around 20 minutes after I anchored.)
And I try to "err" on the loose side if that makes any sense. Too tight is a bad thing, a scoosh too loose is only (maybe) noisy.

Checking the valve clearance is mentioned in the FL120 manual to be done every .... hours, as far as I remember.
To be honest, I never did it. I'm doing a lot of maintenance on our Lehmanns and Velvets, but for what reason ever I did not check the valve clearance so far.

How often are you doing this job? Following the recommended service intervals?
Was an adjustment necessary or was it just a check and o.k.?





best regards / med venlig hilsen
wadden