Hi Everyone!
To start I want to appoligize about this being so long winded, but I feel its only fare to give you the background.
Several years ago I bought this used 89 S10 Blazer 4x4. When I got it the 4x4 and the cruise control didn't work. No biggy, I'll fix it when I get time. About a year later the transmission went out, so I took it to this small shop to have rebuilt. Well, a few days later the guy calls me to say that while test driving my truck.....HE WRECKED IT!!!![:@] All body damage, nothing with the frame, but still, it really pissed me off. Ecspecially when I found out he didnt have insurence! He didagree to pay for all the damage, which he did. even paid for a rental car for me. But anyway......I drove my truck and followed the guy to the bodyshop. On our way, for some reason I started messing with the cruise control, and it worked!!! I told the guy that at least the cruise was working now and he said that there were some vacuum lines that were screwed up and that fixing them must have fixed the cruise. Just for ****s and grins I checked the 4x4 and it worked to! Ok...so that part of the deal is kinda cool, even though I am still pissed at the S.O.B. After the bodywork was finished, the guy picked up the truck to do some other things to it. When I got it back from him, the cruise still worked but the 4x4 didn't. I was not about to take it back to him to have him look at it.
This leads me to my question(s). But first, here is what is happening. When I use the shifter to go into 4hi or 4lo I can here is going in and when driven, it is geared down and sounds like it is in 4x4, but my front wheels are not turning. kind like the front hubs are not locking in. The vacuum actuator didnt look like it was in all the way so I hooked up another vacuum line to it and it went in all the way, but still no 4x4...at least no indicator lights.
I guess what I am asking is...is there an adjustment to this cable thatis causing itnot to lock in at the tranfer case? Could I have a bad vacuum switch not causing the actuator not to operate right? Is there a fuse that maybe I am not aware of? I am at a total loss on this. Any help or input that you can give would be great. Thanks in advance and again, sorry its so long winded.
-kpiper

Oh yea....if that guy who wrecked my truck is reading this.....You are a no good S.O.B. that shouldn't be allowed to hold a wrench!!!!!!![:@]

 

This may help.
https://blazerforum.com/m_52228/tm.htm

 

Hey thanks for the link. I will do some more to it and get back to you!
Thanks again,
-kpiper

 

Ok, so this evening I was working on my truck. I did what Hanr3 said in his post as far as checking the transfer case and it was fine. The front drive shaft locked as it should when put in 4Hi, but still no 4WD. I checked all the vacuum lines and they all seemed to be good but my vacuum actuator was not.......um...."actuating?". Was not compressing anyway. So I jacked the truck up off the ground to see if the tires spun and checked again. Still nothing. So I took a different vacuum line and hooked to the actuator and it worked and I had 4WD.
Here is my question. Since we have pretty much determined that it is a vacuum problem and the vacuum lines and the vacuum actuator seem to be good. Does that just leave the vacuum switch? How does this part work and could this most likely be the problem? Also, I still did not get any 4WD lights on my console when the 4WD was working using another vacuum source. Does the vacuum switch have anything to do with the lights or can this be caused by a fuse somewhere? Any further help would be great and thanks for all the help so far. Its really been great!
-kpiper