Sip Belt compressor. Locked up.

[ukracer]

A while back I was using my compressor spraying. It took a while (because i could not hear the compressor) but it became apparent there was low air.

Subsequently investigations found the trip had stopped the motor. I reset the trip and found the motor worked but the belt did not. The reason for this is because the compressor section has locked up.

The large fan wheel turns almost full circle and then meets a bit of restriction and then stops dead. It then does the same the other direction.

Any suggestions please.

 

[The_Yellow_Ardvark]

Dropped valve?

 

[Woody.v8]

Dropped valve?

There aren't any valves to speak of to drop, just a valve plate with reed type valves on it.
I would say either rings seized or motor knacked

 

[rtbcomp]

Dropped valve, or bits of valve.

It's head off whatever it is

 

[Woody.v8]

Now that I've actually read the ops post
Whip the head off and have a look

 

[Chillitt]

Busted con rod is my bet.

 

[Woody.v8]

Is there any chance any of the air filter has been sucked in?

 

[dannyp]

my money is on bust conrod or big end cap has come loose and fallen off

 

[brightspark]

my money is on bust conrod or big end cap has come loose and fallen off

sounds about rite or crank has snapped

 

[p0689109]

concur on crankshaft

 

[rtbcomp]

concur on crankshaft

If the crank has broken you may be able to wobble the pump pulley slightly.

Remove the bearing cap on the opposite end of the crank to the pulley, turn the pulley and see if the exposed end of the crank turns.

 

[Wallace]

The large fan wheel turns almost full circle and then meets a bit of restriction and then stops dead. It then does the same the other direction.

Any suggestions please.

This would most likely indicate something is in the bore restricting the stroke. Remove the cylinder head(s) and take a look, make sure to mark the heads and valve plate(s) relationship so they go back on as they come off.

 

[ukracer]

my money is on bust conrod or big end cap has come loose and fallen off

Bang on the money...

Next question do they sell parts for these things....

 

[ukracer]

I had hoped to get a new con rod and bearing etc but I am guessing at that price its not worth bothering.

I can't even find the model on sip website... Its the same as this so not a one off.

Its a sip workshop 420/150

 

[dannyp]

i've got the same issue here, got a pump that the valves gave up in, i cant bring myself to throw it out as it only needs new valves but same now as when it broke, add the cost of the parts up and its daft not to put a whole new pump on.

the rods in these compressors are like a lot of small engines there is no seperate shell bearing the rod itself is the bearing

 

[dannyp]

problem is it's chucked 1 rod so whats the other like

 

[slim_boy_fat]

https://www.sipuk.co.uk/sip-50904-con-rod-compressor-part.html

might be worth a bell to them to see if it fits?

If you click the "Tips" tab, it tells you which machines it fits - don't think it'd do the OP's one. But as you say, might be worth a call anyway.

 

[p0689109]

Get a replacement unit and use the tank as more capacity.

 

[ukracer]

Get a replacement unit and use the tank as more capacity.

Don't wanna spend that sort if money.

 

[brightspark]

buy a new pump