Tyre compressor in engine bay??

[TheBeastie]

Hi

I have just got a basic T-Max compressor to do tyres and I was wondering whether it would be a good idea (or otherwise) to try and mount it in the engine compartment to save it rattling around in the back.

The issues I see would be probably needing to get a longer air hose to reach all the way round (but possibly not since I haven't stretched it out yet) and where I would put it.

The benefit, other than not rattling around would be I could wire it in (through a safety switch so it doesn't go on by mistake) rather than using the crocodile clips.

Has anyone done this, and if so advise if it is a good idea or not, and where did they put it? Also any things to be aware of??

Any help or thoughts much appreciated

Best wishes

Malcy

[western]

Or fit it to the behind seats bulkhead.

[Diff]

The only thing I can think of is that the compressor will be drawing hot air from the engine bay. In theory this isn't a brilliant idea because the compressor will get hotter quicker and will have difficulty shedding the heat generated by compressing the air. This may affect the life of the compressor if it has to work hard when inflating tyres for example.

Performance will also be worse if it is compressing hot air rather than cooler more dense air. This is more relevant for these small electric compressors than say an engine driven one.

Regards,

Diff

[TheBeastie]

Thanks guys

That is really helpful input. Looks like mounting on the rear bulkhead would be a much better idea. I will try and see whereabouts it might fit comfortably.

I suppose an added benefit is that I could link it straight into the battery since there is little danger of it getting accidentally switched on without my hearing it.

It would be handy, however, to have it coming off a feed that only works when the ignition is on since that would save running the battery down.

Would that be complicated to set up? And how best would I do it? Not done any auto electrics yet!

Thanks and best wishes

Malcy

[Guest WALFY]

In the clump of wires behind the radio there will be an ign switched wire. Not sure of the colour. If unsure put a test fluke across the wire and turn the ign on and off to test the circuit. Not the best way of doing it but it works for me. Just extend this down to the fuse box, run it through a new fuse and then onto your chosen location for the equip you wish to wire in.

HTH

[Diff]

This is one way of doing it:

If you take the fuse box cover off, you can choose an ignition controlled supply to one of the fuses. Use a piggypack connector to connect a new wire to the largest ignition controlled supply wire you can find, then wire in an inline fuse of the correct rating in the new wire to your compressor switch.

Regards,

Diff

[western]

Ignition controlled wires are

plain white

or

white/orange [used for air condition systenm power feed]

or

white/red

any of those will do.

[Br00n1e]

or wire it in to the battery through a relay using the ignition controlled wire for the switch

[streaky]

These China made compressors like Max Air, T-Max, Vaiar etc are not really designed for under the bonnet mounting. One of the guys on our middle east forum put one under the hood of his J33p Wr@ngler....some plastic parts of it started to deform from the constant heat they they are subject too. He moved again!

If it's an under bonnet unit you want then look at some of the Australian brands, Blue Tongue, Big Red, Magnum twin head etc...even a Thompson from the U.S would be better than the Jap stuf for this application. I have a couple of ARB compressors going spare and was toying what to do with them...under bonnet mounting is not one of my ideas!

Compressors don't like excessive heat and dusty enviroments...the engine bay has both. My mate Jack had an ARB under the bonnet of his Pajero....it was always cutting out when he wanted to inflate his tyres after a day in the dunes. My Max Air would pump up my 4 tyres and then 2 of his before his ARB had cooled down and was ready to run again.

I have mounted mine under the rear seats with a 5 gallon tank under the rear arch and a 150psi pressure cut-out switch. Push-in air connectors are installed on the left and right side of the car for rapid deployment of the airlines.

It might be different for the UK vehicles because of your lower ambiant air temperatures...but I rekon it still gets too hot under the bonnet to mount one perminantly.

Regards.

S

[TheBeastie]

OK and thanks

Rear bulkhead now seems clear as only reasonable location.

Wiring through an ignition line also seems to be good route.

If I mounted a relay in the battery box under the passenger seat - to minimise large cable runs - I could run thick cable from battery to relay and then relay to compressor and thin(ner) cable from relay to ignition cable in dash, with perhaps a safety switch on the dash as well??

I presumably wire the negative off the compressor to an earth point rather than back to the battery? If so where is the best place to make a good internal earth point or do i have to go through the floor to the chassis?

I recall seeing several posts about wiring relays.

Presumably I will be able to work out suitable relay from the 30 amp requirement of the compressor.

So I would need a suitable relay, a rocker switch, four lengths of thick battery type cable (battery-relay and relay-compressor), several lengths of thinner cable (relay to switch, switch to white ignition fed cable) and a good earth from the compressor to the metal framework.

If any improvements on this route please advise. Thanks for your time and trouble

Best wishes

Malcy

[Mo Murphy]

four lengths of thick battery type cable (battery-relay and relay-compressor)

Wire capable of handling 30 amps should be sufficient, battery cable is awfully big for this application