Thumper Twin Air Compressor install

[Silveredition]

Thanks for the comments / suggestions / opinions offered so far - all have been taken on board!

This morning I have managed to have a little play with it. As far as an additional on/off switch / pressure switch goes - I don’t think it is needed. The compressor has a 120psi cut out on it already. When the end hose section is disconnected (the tyre end with the gauge attached - about 300mm long) the compressor cuts out after a couple of seconds (I assume at 120psi). All I need to do is to convert the end to a clip on style, with a trigger. This will effectively turn the compressor off when the trigger isn’t compressed, or when it is removed from the valve....
I have had a bit of a look inside the compressor - it appears to be greased (with a clear grease) well in places, and not so well in others - there was also a fair bit of swarf above the pistons (on and around what I assume are the reed valves). I haven’t managed to take it apart far enough to find the air intake yet...
Will have another play with it tomorrow....

 

[Jason Watt]

For mine - I wouldn't rely on the Thumper's pressure cut-out mechanism.
It has a thermal overload mechanism as well - ditto.
I wouldn't want to be anywhere near your vehicle with 120 PSI cold in an off-road type tyre.
Maybe, just for safety's sake, install a regulated blow-off valve in-line.
Thinking ...WHHHHRRRRRRR - Pssst-Su-tu-tu-tu
Most automotive compressors are designed for INTERMITTENT use only, regardless of brand name.
50% duty cycle at best i.e. 5 minutes on, 5 minutes off or thereabouts.
Hint: Soak the dry foam air filter in some light weight oil and squeeze out as per a motorcycle air filter.
Catch a LOT more dust that way.

 

[Silveredition]

For mine - I wouldn't rely on the Thumper's pressure cut-out mechanism.
It has a thermal overload mechanism as well - ditto.
I wouldn't want to be anywhere near your vehicle with 120 PSI cold in an off-road type tyre.
Maybe, just for safety's sake, install a regulated blow-off valve in-line.
Thinking ...WHHHHRRRRRRR - Pssst-Su-tu-tu-tu
Most automotive compressors are designed for INTERMITTENT use only, regardless of brand name.
50% duty cycle at best i.e. 5 minutes on, 5 minutes off or thereabouts.
Hint: Soak the dry foam air filter in some light weight oil and squeeze out as per a motorcycle air filter.
Catch a LOT more dust that way.

I am still trying to find the air filter on it!!

Also - with the 120psi cut out - I am only thinking of utilising this as a means of turning the compressor off automatically whenever the hose isnt connected to a tyre.

 

[Pubski]

I only have the smaller one but i hard mounted mine under passenger seat made a manifold with nitto outler pressure awitch and quick connects for my air locker wired into carling dash switches. The internal soldering was terrible so i bought new relay fuse and circuit breaker setup. So far works alright though i tripped the circuit breaker pumping up my tyres last trip

 

[Batts88]

This may not be relevant to you set up but if the circuit breaker is mounted under the bonnet the heat of the engine can cause it to trip sometimes. I use to have one mounted on the fire wall under the bonnet and it tripped out on a really hot day so I replaced it with a fuse.

 

[Pubski]

yeah i thought this might be the issue its actually mounted between headlight and battery on my Discovery 1. It's technically not in engine bay but it may still be too much heat soak for it

 

[Silveredition]

So, things have been ordered - 3b&s twin core cable, a 120amp Narva circuit breaker, 4x 175 amp Anderson plugs... I have also purchased a clip-on fitting for the end of the hose to get rid of the screw-on fitting and gauge (will continue to use me hand held gauge).

Next week will be pulling the compressor apart, fitting a new air hose and filter, and looking at re-wiring...

More to come!

 

[Silveredition]

Pulled it apart - down to having to remove the con rod, so I chickened out from going any further... LOTS of aluminium filings / swarf through everything...
I also found the air filters, which would involve a lot of mucking around to make them remote mounted....

 

[Marck]

Do you know what they lube the cylinder with ?

 

[Silveredition]

Do you know what they lube the cylinder with ?

It looks like a clear / white grease... which I would imagine would disappear pretty quickly with piston movement.
In the top pic you can see the piston ‘ring’. This may stay dry of lube???

 

[Marck]

Hmmm now I want to pull mine apart its a dr air 150lpm unit I recon they would look very similar inside. I am home in 2 weeks if I remember I will give it ago.

 

[Batts88]

Have you sent them an e:mail to let the know about all the metal filings you've found and that their Q.A. is up the s#it.

 

[Lovey]

Is it ok to run these sort of air compressor on their side and not in the upright position?

 

[Silveredition]

Is it ok to run these sort of air compressor on their side and not in the upright position?

I hope so, as this is what I am intending on doing. I can’t see any obvious reasons why is can’t be run this way..

 

[Pubski]

Mine is mounted on its side under passenger seat hasn't blown up yet.......

 

[Silveredition]

The decision has been made to mount the compressor in its side under the car between the exhaust and gearbox (about the only place it will fit outside the cab!). I don’t know how long it will last - but I will give it a go anyway.... I have tacked together a mounting bracket (photos to come next week), and bought an additional rear demister switch to use as the on/off switch. I am hoping someone here can help me with wiring it in... I have attached a few photos of the switch and wrote numbers 1,2,3 on each of the terminals for ease of explanation. I assume there needs to be switch power in (was going to go from the acc box), power out, and power to the light on the switch?? The original switch on the compressor is a simple one wire in / one out on/off switch.... any help would be greatly appreciated!

 

[Batts88]

Are you setting the switch up to activate a relay to turn the compressor on or turning the compressor on directly off the switch ? If going the 2nd option I would go directly off the battery with a fuse and make sure the switch can handle the amps the compressor draws and probably add 10amps or more for a safety margin so you don't burn the switch out.
I've always had mine directly off the battery via a fuse and switch without any problems. I'm installing a 2nd compressor soon and will be using a Narva 50amp ON/OFF/ON switch so I can choose between compressors but won't be able to run both at once.

 

[Silveredition]

Thanks Batts88. The current switch triggers a relay (I assume - as there are 2 x 90 amp relays on the circuit board - and there is no chance the tiny switch wire could handle 90 amps), so i intend on using the same switch wires (but obviously lengthening them). I hope to wire the switch into the accessory wiring ‘box’ in the engine bay - so the compressor can only be turned on when the engine is running - I might try a 5 amp fuse in the slot and see what happens...

 

[matt82]

if you use an inflater on the end of the hose that has a trigger it will read accuratly when you let go of the trigger.
and then you should be able to rely on the pressure switch built into the compressor

somthing like this should do the job then you can leave the compressor on the whole time you are inflating your tyres



This is all conditional on the hose being strong enough to manage the pressure that the compressor gets up to prior to its cutout switch activating.

 

[Silveredition]

A small bit of progress - mucking around with a cradle to mount the compressor... lots of tacking / cutting / adjusting.... not the best photos, and the shape is awkward as I have to go under the exhaust on one side and over the drive shaft on the other...