Nooby struggles with 4wd vacuum switch

[Superjustable]

Hello my friends. Got a problem with my 40 not engaging the front drive shaft. Realized this when up on jack stands doing the brakes we tried to engage 4x4 to run in the front drums a bit but no dice. I have looked thru the forms to get some idea. Could anyone give me a place to start, have not verified vacuum at the case yet. Thanks

 

[fzr400guy]

Check the vacuum hoses going into the shifter on the transfer case. I took apart and resealed the switching unit on the firewall and even ordered a new diaphram before I realized the 2 rubber hoses going into the transfercase had holes from rubbing up against the frame. I could have kicked my own ass after doing all that work. BTW I'm running an SBC/700R4 combo.

 

[Superjustable]

Funny! I've wished I could kick my own ass soo many times! I replaced both of those hoses earlier . The fwd worked during the winter... curious... Had it up on jack stands for a really long time don't see how that would have changed anything though . I'm still reading the posts and there is a wealth of info on this subject should be able to find the problem just need some more time and info. Thanks

 

[Superjustable]

BTW it's an early 71', Is there always an indicator light for fwd in these models ? Don't see it on mine could be disconnected.

 

[fzr400guy]

The nice thing about the system is its simplicity. If all the rubber hoses are good then I would just take some RTV to the vacuum switch on the firewall. You worst case scenario of having to replace the diaphram in the shifter on the transfercase.

 

[merlinridesagain]

I'm guessing that switch on the vacuum shift should find it's way to turning the lamp on the dash just below the right turn signal or at least it's there on my 8/71. Then again mine doesn't work as one of the connections has broken. A minor fix, but low on the list of priorities right now...

 

[fzr400guy]

BTW it's an early 71', Is there always an indicator light for fwd in these models ? Don't see it on mine could be disconnected.

Yes, the light is next to the right side of the gauge cluster below the right turn signal indicator. My light needed new wires to soldered to it. But after many hours of trouble shooting and hose replacement it all fuctions perfectly.

 

[CruisinMT]

I freed up my vacuum 4wd on my 67'with some Wd-40. I can always hear it engage and disengage. take off the little shield and spray a little in and start it up and open and close it a few times. Spray a little more and retry. You just might be able to save it. been going for 4 years on mine without a hiccup since.

 

[colofish]

Search some more.

I had the same issues on my '69 and ran across some really good info. on the light not working, but don't recall right now what it said.

I did find and replace a cracked vacuum hose and then found that the copper? tubing that the hose attaches to had a hole worn into it from rubbing against the frame. I put a section of rubber fuel line around the hole and it works like a champ now.

 

[Superjustable]

I freed up my vacuum 4wd on my 67'with some Wd-40. I can always hear it engage and disengage. take off the little shield and spray a little in and start it up and open and close it a few times. Spray a little more and retry. You just might be able to save it. been going for 4 years on mine without a hiccup since.

Thanks so much for the wonderful advice ! Are you talking about the upper switch on the firewall or down at the TC?

 

[Superjustable]

I'm guessing that switch on the vacuum shift should find it's way to turning the lamp on the dash just below the right turn signal or at least it's there on my 8/71. Then again mine doesn't work as one of the connections has broken. A minor fix, but low on the list of priorities right now...

Thanks to all posters! I'm new to the form- I bought my dream machine last November after a long courtship with the original owner much back and forth and so on . as far as I can tell the cruiser is original with no rust(owner put an under coat on it) it has the original f engine with 46,000 on the OD( the OD doesn't work I found out).Still has the original North Hollywood Toyota dealer license plate bracket(previous owner bought it from a San Antonio, TX dealer but I understand that N.H. Toyota was the only importer back in the day could use a little clarification on that one though). It sat in a barn near Denton TX for about 13 years and did not get the most loving care mechanically before it was parked -but it wasn't too bad it started and drove up on the trailer by itself...The Dragon is very red...but what the heck right?