Which pipe or pipes do I block up

Hi Guys my first post so please be gentle lol. I recently found that the 4 x 4 system on my 2007 Jimny was not working It was making all the right noises but the hubs were not engaging and the green light was flashing. Following extensive research on this site I was able to detect that I had a problem in the vacuum system which wasn’t hard to prove as the pipes that run along the front axle were both corroded through!! Anyway I’ve decided to go for manual hubs to cut out the vacuum issue. The hubs seem relatively easy to fit but I’m confused as to which pipes to block off to fool the green light into not flashing. I think that seeing as the existing pipes are well corroded I will need to look at blocking the system somewhere in the engine compartment.
I’ve read a very good guide on here that shows a screw inserted into a pipe somewhere near the vacuum check valve
(I think). Not being very well acquainted with mechanics in general my question is this

Is there only one pipe to block up at the point near to the check valve. I’m confused because I’m unsure at what point the vacuum pipe splits to feed each wheel and also if there is a separate pipe at this point for engaging/disengaging the vacuum system. I know this may seem a simple thing to you experts out there but we have all got to start somewhere!!!

I’ve included the photo of the pipe blocked off with a screw

Have a look under the car, roughly below the drivers seat and you will see two metal pipes side by side coming down from the engine bay vacuum solenoid area Attached to these are two rubber/flexi pipes which head towards the front axle and from there to the left and right hubs. Pull the pipes off the metal tubes,cut a couple of inches off each ,,push one piece partly back over the metal tube,bend the rest back on itself and secure with a small zip tie. Repeat with the other tube. Failing that,,just stick a suitable screw into the end of each piece of cut off tube. Tie up the loose ends of pipe going forwards and that's it. The vacuum system now thinks it could suck the chrome off a Chevy front bumper and will work accordingly.

Thank you. Am I right in thinking that once I carried out your cunning plan I will be able to select ‘low gear’ with the 4L button

block off the pipes you have left going to the axle as well. This stops them getting dirt in (though from the description of the pipes on the axle it wont matter :laugh: )

Doing that will make it think all is well and change ratios as you want.

Another way of doing it is to remove the vac hub solenoid altogether. Its located under the battery. There is an electrical plug with two white wires coming out of the solenoid block. Chop and short these wires and it will think all is well. The vac line from the manifold can be blanked off at the manifold and the rest of the lines removed completely for a tidy job. Put a loop of pipe between the two ports on the wheel hubs to stop dirt entering there. Jobs a good'un

Thanks for the responses. I’ve been out to the Jimny and had a closer look at the state of the vacuum pipes and it appears that right from the first section of metal pipe in the engine bay to the last section before the flexi pipe at the wheels is totally rotted through in a number of places. I tried blocking off the flexi pipe under the drivers seat but it didn’t do any good the green light was still flashing. I then tried blocking off at the point in the engine compartment where the flexi pipe first joins the metal pipes leading down under the vehicle again green light still flashing. This may sound a very naive question to you experts out there but do I need to have the four wheel drive actually physically engaged on the front wheels for this pipe blocking technique to work on the green light. I can hear the solenoid working when I press the 4H button and the light flashes. Obviously I know the hubs are not going to automatically engage as the vacuum pipes have more holes in them than a collider!!! I’m quite happy to accept the blame for the pipe block fix not working if it’s something I’m doing wrong but if anyone has any further suggestions I would welcome them. Thanks

You need to block the pipe that pulls the hub on. (Blocking both is sensible though)

When you engage 4wd, one of the solenoid air valves changes over and connects the hub to the vacuum line. There is a vacuum switch on this line, and if a vacuum builds up, the switch operates and the car thinks the hubs are locked, so it carries on and lights the light, engages low etc.

What can happen is the air valves stick so that the one to pull the hub off is leaking to atmosphere, and you still can't get a vacuum in the line. This may happen if water or dirt get into the filters attached to the open ports by the air solenoids.

The best solution now is to find the vacuum switch and join its wires together, as Riccy says, then you can block the vacuum port on the inlet manifold and do away with the whole system.

Thanks for the prompt response. I had a feeling that the solution Riccy suggested to deal with the issue by taking the vacuum system right out of the game would be the final option, but to be honest as you have probably worked out for yourself I have very little mechanical knowledge and the thought of cutting wires is a little daunting!! Do you know if anyone has produced an ‘idiots’ guide to doing this preferably with images.

Picture from the wiki: www.bigjimny.com/mediawiki/index.php/Vac...checking_and_testing

That picture shows the two white wires I mentioned about joining. They come out of the solenoid block and into a inline plug. You could unplug them and pop a wire between the terminals to try it before chopping anything

Thanks Riccy. I’ve located the wires in the photograph, undoing the plug might be another story. I think that Jimny mechanics must have the smallest hands in the world. I appreciate you virtually talking me through this process. It’s raining heavy at the minute here in East Yorkshire and I’m at work next week so it’ll be probably Thursday before I get to have a go but I’ll let you know how I got on. Thanks to everyone who have so far shared their knowledge

Can you get a scotchlok connector over the wires? that will join them, and can be removed later. I can never get Suzuki wiring plugs undone without breaking them

Looks so easy when I have the broken bits in my hand- just press the clip (but I did- as hard as I could too)

That’s a thought the connector is well gunked up and I reckon I would have a job on trying to release it. Using a Scothlok seems an easier solution. I’ll give t a try and report back. Thanks for the suggestion.

Probably very obvious, but you have to remove the little bit of plastic that acts as a stop in one groove to get two wires to go straight through.