td5 120amp with vac pump inplace of 300tdi aircon compressor

[Kumuna]

Still learning the extent LR engineers built oil leaks into my tdi defender. After a solid go during lockdown at sealing everything mechanical on the defender ( new rear seal and clutch, rebuilding gearbox and case, replacing rings and bearings, new head and hoses, and comprehensive tidy up of the engine bay wiring, clamps, paint) in the hope the 'negotiable' could be eliminated... the 6 month old Unipump vacuum pump let go and restored the presentation to original. The last one got 18 months but I got lucky with warranty this time...good to have a win. 4wd Industries happy to replace the Unipump without question. I also learned from Mike at Brittanica Restorations any leak in the vac line from the brake booster upstream will pump air under pressure into crankcase and then through the cyclone (changed to a ProVent which can't keep up with separation) find its way through the turbo, intercooler, intake, combustion and some out the exhaust. There must be a better way.

I've not looked seriously at the electric pumps yet as I'm personally NOT good with electrics as a rule, but am wondering why I can't find info on the TD5 alternator swaps. I understand it doesn't fit in the TDI alternator position due to the vac pump dimensions, and requires an oil feed and return, but wondering if it can be placed in the aircon compressor position with a suitable bracket, and an oil feed line from somewhere....turbo feed perhaps...maybe not.

Hoping there's some insight into rights and wrongs and keen to work it out.

Thanks all.

[incisor]

when i looked into this i couldn't find a solution that was not too close to the exhaust manifold...

[Kumuna]

...thinking out loud just wondering if the oil cooler hose lines could be used for feed and return or lack enough pressure.

[Kumuna]

Couple more questions..

Do TD5 alternator vacuum pumps have a habit of leaking oil under feed pressure, and emptying the sump...?

Can the vacuum pump itself be removed from the alternator and hooked up to a 12v motor?....though I'd like 120 amps also.

Cheers
Sven

[shack]

Couple more questions..

Do TD5 alternator vacuum pumps have a habit of leaking oil under feed pressure, and emptying the sump...?

Can the vacuum pump itself be removed from the alternator and hooked up to a 12v motor?....though I'd like 120 amps also.

Cheers
Sven

I've seen pumps that were "oily" but haven't seen a "rampant" leak.

I think if you were going to go to the bother of making a stand alone vac pump with the TD5 front end, there would be far simpler solutions to be had.

The first thing to do is actually check if the booster is leaking, they crack either side of where the master cylinder bolts on, they lose vacuum, the pump runs non stop, and it's just a race then to the finish line.

That said, the piston pump is not a great thing, I've tried to go electric, but had to many issues with the relay dying, I bought a different sort with a resistor but that's been sitting in the shed for 2 years... Somewhere.


PS. I fitted a disco 1 alternator that was 100 amps, so not a lot of gain there going to the TD5 one.

Cheers
James

[AK83]

Oooh! .. I dunno what happened to my reply ... maybe I misposted it.

Anyhow, I tried to say same as Shack .. if you want more power from the alternator would be easier to get a D1 300 Tdi alt .. at 100A.

If you worry about electricals, you can get self contained electric vac pumps for not a monstrous outlay.

There are a couple of types available and depending on your budget and tolerance for noisy pumps.

Self contained electric vac pump setup on ebay.

This is just one example, and there are other types .. but just to give you an idea.

The major price issue with these types of products is the huge postage price.
You can locate the individual parts and pieces for just a bit less outlay, but this set up is simply plug and play .. just run a power feed from switched ignition(or fuel solenoid) via another relay and to earth and the hose to your booster!
You don't need a lot of electrical knowhow to accomplish that.
All the auto switching is contained within the system there.
From poking my nose around I think they're set up to produce vacuum to about 19-20mmHg.

My vac pump is leaking again too, and weighing up options

[Kumuna]

Thanks James. I haven't any experience with a TD5 and good to hear the alt. is not an endemic problem child. Speaking of, I learned of the TDI booster crack and leak a couple years ago and sure enough... the new one transformed braking and inspired getting the rotors machined, and pushed the newfound defender driving experience into 'functional' for a while. I am also a bit suss on the gromet and hose fitting that attaches the vac line to the booster itself...though all new it seems to be a little too capable of leaking depending on which way the hose pulls it.

I've read a few have had headaches with noise and relays etc on electric vacs and imagine that would be something I'd like to avoid in favour of a mechanical approach, but I'll look into it a bit more. After replacing the rectifier/regulator/internals and bearings on the Marelli 65amp, the front pulley/fan failed, with a 100amp Hella now doing its job beautifully through a DC/DC Projecta. Now discovering the TD5 alt possibility a year on is bittersweet but if it removes the vac pump failure issue I will call it a win albeit expensive...if it can also become a good 2 bird replacement option for the Marelli 65amp even better.

Thanks Arthur, that ebay pump sounds ideal and even if expensive for what it is thanks also to shipping, it is still comparable money to the Unipump I need to replace, and seems a no-brainer if its longevity gets it beyond 6 months. Should be fine hooking up a relay but if I had to match up switches, check valves, wire sizes etc it would get pretty agricultural pretty quickly.

I'll dig around, cheers guys.