Valve clearance

MapisM said:
That's actually 14,64 litres, i.e. 1.83 a pop - which is the reason behind the MTU name "183 series", back in the days when they were using the same block.
But most importantly, it's 2 valves. We don't want to drive Chris H mad looking for some valves that do not exist, do we? :ROFLMAO:
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He won’t as theres only two tappets per pot for the quads like mine .See the pic I posted earlier, they use a bridge .
 
I am fully up to speed with ramp cams - after all they have been in use since the 1930's.

Having been privileged to get free dyno time at LEDAR as long as I bought the tea, milk and biscuits I clearly recall my set of camwheels with slots that allowed me to make 30 degree alterations to both inlet and exhaust valve timing on Kawasaki engines - subject, as always, to mechanical clearance.

Many hours proved to me quite conclusively that cam timing bought little improvement in power or tourque compared to carburettor adjustment, ignition timing or exhaust dimension. Opening the exhaust valve15 degrees sooner predisposed the engine to rev - and be less fuel efficient - 10 degrees later gave less RPM but a 'fatter' middle to the charted power curve.

This basic premis will carry through to diesel engines, even low RPM ones like the excellent MAN. I dont believe that a slightly maladjusted valve clearance would be significant unless tight. It never seemed to matter with Lister and Gardners.

To rotate the engine for valve adjustment I knocked up a momentary switch and two wires, one for the solenoid relay spade terminal, the other with a small crocodile clip for a live feed.

Operating the switch cranks the engine to the right place quickly-and safely. Best to make sure the stop button is pulled out...................
 
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rotrax said:
Operating the switch cranks the engine to the right place quickly-and safely. Best to make sure the stop button is pulled out...................
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Interesting.
When my engines are unused for some time, I'd love to crank them for a few seconds to circulate oil, before actually firing them up.
But both start and stop are controlled by a key, and it's obviously impossible to keep it in the cranking and in the stop position at the same time.
If by chance you know an easy and safe way to keep the stop solenoid active while cranking on MAN engines, I'm all ears.
I don't mind fiddling with them directly in the e/room , rather than trying to modify the key wiring on the dashboard.
 
Some stop solenoids are "energized to stop".
It sure was in my old Caterpillar 3116, but I never investigated (so far) about our MANs.
If you did try, it sounds like it's the same with them.
My understanding is that it's the other way round in most (if not all) electronically controlled engines.
But both the Cat 3116 and the MAN D2848LE403 are fully mechanical, so I'm not too surprised to hear that.

Leaves me wondering what happens trying to keep the stop solenoid energized while cranking.
But I wouldn't fancy blowing up the electrical circiut...!
 
MapisM said:
Some stop solenoids are "energized to stop".
It sure was in my old Caterpillar 3116, but I never investigated (so far) about our MANs.
If you did try, it sounds like it's the same with them.
My understanding is that it's the other way round in most (if not all) electronically controlled engines.
But both the Cat 3116 and the MAN D2848LE403 are fully mechanical, so I'm not too surprised to hear that.

Leaves me wondering what happens trying to keep the stop solenoid energized while cranking.
But I wouldn't fancy blowing up the electrical circiut...!
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The Bosch stop solenoid on my DV 20 had two windings, one a heavy one, energised when cranking and a lighter one energised when running.

If the current was held in the heavy winding it got very hot and could burn out.

So, OK to leave it on while cranking.

Two wires from the momentary switch? One to the starter solenoid, one to the stop solenoid.

Should replicate what your key switch does.
 
rotrax said:
Two wires from the momentary switch? One to the starter solenoid, one to the stop solenoid.

Should replicate what your key switch does.
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Indeed, except that with the key switch you can't energize both at the same time - you either turn the key clockwise to crank or CCW to stop.
I guess I could add a separate momentary stop switch, and keep it pressed while cranking with the key.
Doing that from the dashboard would also be convenient for seeing the oil pressure build up on the gauge.
I'm just fearing that energizing both start and stop in parallel could short circuit something somewhere...
...Though I can't think of any logical reason why it should.
 
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