Sabroe SMC108 loading fault

[gibbo88]

Im having a problem with a Sabroe SMC108. When i try to run it will load every head but the 75%. This problem seems to have started since i removed all heads and liners,and changed discharge and suction valves on all liners. I have changed the solenoid coil,and taken the solenoid assembly apart to check for any blockages and found nothing. Also have taken the head and cylinders out to check the mechanical side of the loading gear and all seems to be fine. All pressures are fine,and motor current is fine too. So nothing appears to be wrong with the control circuit side of things. When re inserting the liner i put the loading gear in the correct load position,then once in place loading gear went back into unload position and i could see the valve inside cylinders moving to correct position. I cant think of any reason why it will not load?

[Sandro Baptista]

When re inserting the liner i put the loading gear in the correct load position,then once in place loading gear went back into unload position and i could see the valve inside cylinders moving to correct position.

I don't understood: the capacity is ON and then goes OFF immediately again?

[RANGER1]

gibbo88 I assume before you put head on you instal plug & force unloader gear to loaded position ?

If you do not ,unloader pins can jam in vertical position when head is installed .

Also double check both liners suction valves are free to move up & down all the way round in each cylinder liner .
If you are checking that unload mechanism is moving up & down freely , also observe when loading cylinders with plug that after valve seats that you can still screw in plug a bit more .

Did you check bumper clearance & have to adjust , or put same gaskets back in under liners?

[gibbo88]

gibbo88 I assume before you put head on you instal plug & force unloader gear to loaded position ?

If you do not ,unloader pins can jam in vertical position when head is installed .

Also double check both liners suction valves are free to move up & down all the way round in each cylinder liner .
If you are checking that unload mechanism is moving up & down freely , also observe when loading cylinders with plug that after valve seats that you can still screw in plug a bit more .

Did you check bumper clearance & have to adjust , or put same gaskets back in under liners?

yes when i installed head i forced unloader gear into loaded postition. both liner suction valves are moving freely. i put new gaskets under the liners which are the same size as the previous old ones. how do i measure the clearance and what should it be? thanks

[gibbo88]

when i installed liners* not head

[Sandro Baptista]

Gibbo88,

I'm sorry but I couldn't understood the symptoms: The frame load mechanism gets ON and then is unloaded immediately again?

Sorry about my persistence.

[Grizzly]

Hi Gibbo.
Ranger has his finger on the issue as far as I am concerned.
Forgive me for asking what may well be basic questions to you.
But as you say your problems only started after a overhaul.
So it is only fair to assume it is something you have done?

then once in place loading gear went back into unload position and i could see the valve inside cylinders moving to correct position. I cant think of any reason why it will not load?

Correct me for being stupid, but just how are you observing the movement of the loading gear?
How you answer could be the crux of the problem.
Oh! also what is the oil pressure indicated when this comp is running?

Cheers Grizzly

[RANGER1]

when i installed liners* not head

Not sure what you mean here but unloaders should be forced & held in the loaded position with plug when installing head .
Bumper clearance is 0.6 to 1 mm using dial indicator & magnetic stand again unloader gear has to forced into loaded condition .
Minimum oil pressure 3.5 bar
Normal oil pressure 4.5 bar

[Grizzly]

Not sure what you mean here but unloaders should be forced & held in the loaded position with plug when installing head .

We are on the same wave length my friend!

I am wondering whether the plug has been unscrewed prior to bolting the head back into place?
Gibbo does not seem to want to answer.

Grizzly

[RANGER1]

We are on the same wave length my friend!

I am wondering whether the plug has been unscrewed prior to bolting the head back into place?
Gibbo does not seem to want to answer.

Grizzly

Grizzly the first Sabroe I ever did I didn't know about plugs screwed in for mounting heads .
Was lucky enough for them to be ok .
When each bank loaded it went bang so liners then seated etc .
How I didn't do any damage I'll never know .
Same machines (on R22 steel pipe) had high discharge temps after 6 months .
Pulled off heads & found bits of hard type curved square wire .
Found out eventually that discharge valve plates had worn completely through due to pipe dust & scale grinding away.

[Grizzly]

Grizzly the first Sabroe I ever did I didn't know about plugs screwed in for mounting heads .
Was lucky enough for them to be OK .
When each bank loaded it went bang so liners then seated etc .
How I didn't do any damage I'll never know .
Same machines (on R22 steel pipe) had high discharge temps after 6 months .
Pulled off heads & found bits of hard type curved square wire .
Found out eventually that discharge valve plates had worn completely through due to pipe dust & scale grinding away.

Hi Ranger.
Nobody had fitted commissioning socks then?
I have seen the damage the huge amounts of carbon Dust / Grit that is created can cause.
Especially if the plant is on Ammonia and mineral oil.

Fortunately for me I had a older guys to learn from.
So I was spared the trauma of not setting the loading gear correctly.

I suspect "we / you have gotten to near the truth and Gibbo has done a runner?
Gibbo, take note the good engineers admit they make mistakes.
No-one with half a brain is going to criticise we all make mistakes.
Simply with time, the number you make grow smaller.
Hopefully anyway.

I learnt a brilliant Australian saying the other day my friend, FIGJAM.
I can relate to this. If you know what i mean.
How about you
Grizzly

[rattis]

unscrew the plug and measure the actual oilpressure in the servocylinder solenoidvalves do go bad.
but then again if it's after an overhaul the most likely cause is assembling it the wrong way the plug is the Father the holy spirit and the son when it comes to overhaul the SMC