Not turning off - BJ

[benniebez]

HELP ! I'am no mechanic, so bear with my discriptions an all please.
My BJ74 would not switch off for a long time, and I knew it would be the diaphram not getting the vacuum to kill it. I sorted this by getting the correct vacuum diagram for it, replaced all the vacuum piping and it was sorted (for a while). Even the boost light on the speedo started lighted up after this vacuum piping (didn't work before).

Now it all started again. No switching off when I turn off the ignition, the green boost LED do not lit up anymore (while my boost gauge shows full boost) and I have this weird whistling effect coming from the clutch pedal. When depressed, the wistle is gone, and there is no sound as such on the outside, underneoth the bonnet etc. I checked out the pedal and it's workings, looked in the manual, but could not find anything that can have vacuum escaping from (wich should be the cause of the wistle, not turning off & green light). The piping running to the daiphram also do not have any vacuum when tested after ignition swich off. Where must I look ?

 

[Dieseler]

Dues the 13B not have the EDIC same as the 3B if so I would look at that and the wires to it

 

[Stone]

The 13BT uses a vacuum switching valve (VSV) just like the 12HT. You didn't happen to have washed your engine down when your symptoms started? The vsv is susceptible to moisture, and when it's wet it doesn't like to work. When I had a BJ74, I seriously considered doing the relocation because even deep water crossings can get it wet.

It might also be malfunctioning and need replacement. In the meanwhile, you can manually push on the diaphragm to shut it down.

 

[benniebez]

and I have this weird whistling effect coming from the clutch pedal. When depressed, the wistle is gone

This whistling sound is my main bother, it is deffinatly where the vacuum escapes, but where should I start looking ? Strip the dash perhaps ?

 

[roalco]

Does your rig have a clutch booster? They are vacuum activated and if one of the 2 body seals (probably rear if you are hearing it in the cab) or the main diaphram has failed that might just be where your loss of vacuum problems and whistling is coming from.
Good luck!

 

[benniebez]

Does your rig have a clutch booster? They are vacuum activated and if one of the 2 body seals (probably rear if you are hearing it in the cab).....

Yes, where shall I find the body seals ? The main daiphram, are you refering to the cut-off one, above the throttle linkages near the batteries ?

 

[roalco]

No, these seals are on/in the clutch booster body itself, the one that is attached to the master clutch cylinder on the firewall and looks like the brake booster. Go to the clutch section of your repair manual (FSM landcruiser repair manual for chassis and body, page CL-7 to 17)( if you don't have it download it from the address in the sticky at the top of the forum).
The booster diaphram is inside the booster body, and the body seals are at both ends, one between the master cylinder and the body, the other at the firewall side, sealing the clutch actuating (pedal) rod. A leak here can cause a massive loss of vacuum, which will interfere with anything the vacuum system is supposed to power.
A quick check to see if this is the problem would be to disconnect the vacuum line (15mm diameter black rubber hose that goes into the booster just behind the clutch fluid resevoir) from the clutch booster body, plug the end of the hose to secure the vacuum system integrity, start the engine and see if your engine shut down problem and the whistle goes away. You won't have any clutch boost (power assist) so your clutch pedal will be quite hard to depress (but it is driveable this way, you just need a strong left leg!). Hope this makes sense to you....!
Good luck!

 

[benniebez]

Should my 1987/12 BJ74 also have the clutch booster, the mechanic today said no, mine has not. Taking it to him on Friday for the repair, I still heard inside the cab the wisttling effect of the body seals as discribed I asked this qeustion. That means to me there must be a c/booster ? Should I be worried, I want this problem fixed this week, have been too long stalling it with the clutch in 5th.

 

[boogie74]

Hi Bennie,

Sounds like a classic case of Leaky Clutch Booster. Search Clutch Booster in the 70's Forum and you should find the info u need.

Here's a start.

https://forum.ih8mud.com/70-series-tech/292125-clutch-booster-final-word.html

The clutch booster is up under steering column above the clutch pedal.

 

[boogie74]

Hey Bennie,

Just read your other post. If the VSV (hard to find but its down on the side of the engine block behind the injector pump/follow the vac lines under the intake) is toast the problem will be that the engine wont run. My VSV died and the engine would turn over but not run. The VSV that controls the engine shut off is open/lets vacuum through when its switch off (eg ignition off) and moves the shutdown valve with the stored vacuum in the system. Thats why, with your leaky booster the engine keeps running. Vacuum is lost through the busted booster.

 

[benniebez]

Boogie I know it is the b/seals on the clutch booster, why this mechie tells me my BJ don't have a c/booster ????????? Is that true, is he bullsh!tting me ??????

 

[tmarx]

According to TOYODIY you definately do Bennie.

04318 BOOSTER KIT, CLUTCH04318-60040 BJ7*, HJ75, FJ7*..RHD..MTM..(ARL, GEN) 1 31440 BOOSTER ASSY, CLUTCH W/AIR CLEANER31440-60070 BJ7*, HJ75, FJ7*..RHD..MTM..(ARL, GEN) 1 31440B PISTON, BOOSTER (FOR CLUTCH BOOSTER)44642-87502 BJ7*, HJ75, FJ7*..MTM..(ARL, GEN, ME)

31403A VALVE ASSY, VACUUM CHECK (FOR CLUTCH VACUUM)44730-60040 BJ7*, HJ75, FJ7*..MTM..(ARL, GEN, ME) 1 $80.9431430 RESERVOIR ASSY, CLUTCH VACUUM31430-60030 BJ7*, FJ7*..RHD..MTM..(ARL, GEN) 1 31436A HOSE, NO.1 (FOR CLUTCH BOOSTER VACUUM)31437-60060 BJ7*..MTM 1 31437 HOSE, NO.2 (FOR CLUTCH BOOSTER VACUUM)31438-60040 BJ74..MTM 1 31438 HOSE, NO.3 (FOR CLUTCH BOOSTER VACUUM)Not applicable31488B TUBE, VACUUM HOSE TO VACUUM HOSENot applicable90179-08038 *** STD. PART $0.8990461-10221 *** STD. PART $2.8290467-16002 *** STD. PART $1.6691611-60812 *** STD. PART $1.17

ToyoDIY.com

 

[boogie74]

Read the link and search in the 70 series section for other booster related topics. The info you need is there.

Did you find your booster? Its above your feet and looks like the ones in the pictures in the link I gave you.

Cheers.

 

[benniebez]

I suppose you need to remove the C/B first, or can it be done still attached to the vehicle & pedal?
I'am finding it difficult to get somebody to repair this for me, so need to know as much as possible please. If inside the cab, how do I take it off, seems I need to do this on my own with help from a bud. Me only pencil pusher, but still able to get my hands dirty.