Syncro 4&4 Discussion and Q&A last answered over 2 years ago.
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Ive been having fun and games with mine too, im wondering whether its my non return valve. Ive cleaned it but its a right **** to blow through. Does anybody have any idea of the price and part number. Was hoping to see it on the Brickwerks site, but no luck.
Noisy valve only proves you have vacuum, so if there is a problem thats not likely to be it in my opinion.
Sounds to me that you got yourself in a position and then started pulling knobs whereas what you should be doing is preempting the problem and getting the four wheel drive on before its too late.
I would ask a decoupler expert (not me) whether four wheel drive is instantaneous when engaged in a stuck position; certainly your diff locks may take a second or two to 'bite' and it may be that if you are stationary with wheels spinning and no movement that the decoupler wont engage; but thats one for someone else.
Once you have replaced your broken valve take your van out on a bit of loose ground somewhere and try the decoupler/locks again; then get yourself down to Devon and talk about the when and wheres of what to pull and when.
Thanks Mudlark. I can assure you that this was not a 4x4 situation that was something that might have got anyone thinking about pulling on the decoupler first, especially with ATs on. We are talking slight decline and what I thought was dry grass on a bend on a campsite with BMW ford vauxhall etc everywhere.
I pull on the decoupler once every three weeks on average when I go park up on Exmoor for the day. It usually comes on within 2 secs. After being pulled out I tested the 4x4 again several times on various surfaces and nothing.
Your right in that it might not be the valve but fingers crossed.
Its sort of getting away from ghops point really. He just asked for advice as to why the decoupler didn't engage, not on his driving ability.
Anyway, I hope your new valve sorts it out. Interested to know if it does.
Ok you got me worried so I just had a run out to see Syncrospares to ask their advice.
First we bypassed the valve and reconnected the tubes. After looking at the actuator is looks like it has been cracked at some point and fixed with paste. A quick squidge back of the paste and we have lift off, albeit slow on the uptake (5-6 secs) which could suggest a leak in the system somewhere also. hard to tell if the check valve was faulty, it may have developed a slight leak which in combination with the above has been enough to cause the system to fail.
So, next to fit the new valve, order a new actuator an fit that and take it from there regarding the possible wider system leak.
Learning lots, thanks to all. See you at the weekend!
Ha! Glad to be entertaining! Plenty more where that came from I'm sure. Learning heaps which is great though. Just about to meet my boss for my annual review of my pen pushing job with oil under my nails. Hope he doesn't notice!
Quick and final update. New actuator in, new check valve in, still low pressure on vacuum so checked front diff actuator and found two cracked pipes. Replaced these, job done. 4x4 now comes on almost instantly.
Good to hear its sorted. BTW, so long as your VC is OK, you do have '4x4' all the time, not just when you have the difflock engaged. You only need the difflock to prevent wheelspin eg. if one wheel leaves the ground, or when the surface is very poor.
Syncrosport (taking a break as of summer 2024)
Volkswagen Transporter, reloaded.