Offroad-Express

Whilst hunting this weekend the vac pump completely failed. A 3 hr road trip back to Ak was interesting with no boosted brakes
Ive pulled the alt and pump out. its a 24v 35amp- appears orginal.(88 GQTd42)
Im considering buying whole new alt/pump - there's a 50amp unit on trade me.
Any issues I need to consider?
I have a PTO, but am also toying with adding an electric winch, so would like to hear if 24v50amp is enough.
Are the vac pumps by themselves cheap?

hmm be carefull buying ones of trademe especially if its a chinese made one we've had a couple at work that shat themselves big time , could be worth going to a auto spark and seeing if they have a old vac pump lying around and get them to do the brushes and bearings in the alternator whilst your at it

Never seen a vac pump fail but they are really bad for wearing the splines off of the rotor on the alternator where the pump fits on. If they do that they are non repairable. There is a larger isuzu elf unit that bolts on and just needs a small plumbing and wiring mod to fit.


I have on one for a temporary fix welded the pump impeller to the alternator rotor but this makes it almost impossible to service the alternator in the future.

mine died, it was rebuild, was a large bill that came with it , see auto electrician and get the whole thing done in one go, or has your spare still got it's alternator

I am an auto electrician. I have repaired a lot of these but either the rotor or impeller are no longer available, I cant remember which one. When you could get them it was about $500 just for parts. This is for the earlier fine spline pump. The later ones have a coarse spline and don't fail.
The relatively cheap cost of replacement alternators has made these repair's non economical so our suppliers no longer carry the bits.

ChurchurDan - ok thanks re cost to rebuild- what I suspected.
FYi the vac pump made a sudden screeching noise after a 3hr drive past rot, that's when vac was completely lost, up til then, it was in hindsight clearly on low vac.
Coxy - yes I do have complete alt /vac pump off my personal pick a part whale, but for $350 even if its is Chinese, id rather have new than something off a 93 with 250k km.
the question is spend 350 or prob 600-700 with auto elec?
it seems im slowly replacing everything on this over time!!
......a little like my 40 yr old hammer 3 handles and a second head shes as good as new!!!

Just had the same thing happen to mine. I picked up a new aftermarket alternator from an auto sparky for $425.00. I was pretty happy with that because the last alt I had rebuilt cost me about $700.00.

Take your spare alt to an auto sparky and get it checked over. If the splines are good put brushes bearings and an oil seal in it, shouldnt cost more than $150 and will be far superior to a chinese copy.

The later model td42s have the VAC pump driven off the timing gear set and mounted to the front cover, I believe the front covers are interchangeable. Perhaps another option? Then you can use any alt including your old one

TD27eti and Qd32eti from 95 on do aswell