Hi
I have had a similar problem with my HJ61
Everything was working but vacuum was insufficient to be useful
Brakes felt unboosted and bad, 12ht motor wouldn’t always turn off every time
Would turn off sometimes or have a delay before vacuum switch off valve operated.
After a lot of component testing and diagnosis i discovered it was the alternator belt slipping at low rpm and idle
It felt tight but was not enough tension
Once I unbolted and lifted the air con compressor I could get the alternator belt properly tight
All vacuum problems were fixed instantly and haven’t returned
I believe that the 24v alternator with vacuum pump requires a bit of force to turn at idle / low rpm hence the belt slip and poor vacuum problems
The new 12ht replacement belts I put in were from terrain tamer
Good luck
Regards Alex
I have had a similar problem with my HJ61
Everything was working but vacuum was insufficient to be useful
Brakes felt unboosted and bad, 12ht motor wouldn’t always turn off every time
Would turn off sometimes or have a delay before vacuum switch off valve operated.
After a lot of component testing and diagnosis i discovered it was the alternator belt slipping at low rpm and idle
It felt tight but was not enough tension
Once I unbolted and lifted the air con compressor I could get the alternator belt properly tight
All vacuum problems were fixed instantly and haven’t returned
I believe that the 24v alternator with vacuum pump requires a bit of force to turn at idle / low rpm hence the belt slip and poor vacuum problems
The new 12ht replacement belts I put in were from terrain tamer
Good luck
Regards Alex