I recently picked up this '81 and got under the hood. I noticed it's been de-smogged and looks like a lot of vacuum lines are missing. Does anyone have one that could post some pictures of the lines running from the thermostat housing, and any other that might be important? It would be a big help after I do a rebuild of the motor and C6 trans. I'll get a few pictures up myself in the next hour or so.

 

You should have a diagram on the radiator support for your engine vacuum lines.

 

I do, but it's not overly helpful with how much is missing. I don't have a whole lot to go off besides vacuum advance.

 

Ok if you don't need all that hooked up to pass smog test then don't worry of hoses missing and some ports left open like the ones on the T stat housing as they did go to things but if you don't have a vacuum supply going to it then no worry.

You only need about 3 hoses:
1- hose from carb to the dist. for vacuum advance.
2- hose to power brake booster
3- hose to the HVAC control if you have factory AC
So if you don't have AC or power brakes you would only have 1 hose.

BTW my 81 with a 300 six only has 3 vacuum hoses, it has factory AC & power brakes.
Dave ----

 

Depends on what you mean by important. If it is needed for to meet smog visual inspection or pass smog a test then it is important. Otherwise it is not and the truck will run better and get better fuel economy with out it.
And being a 351M the best thing you could to it is source a 400 crank and convert it to a 400.

 

If you need them hooked up, you will have to post a picture of the sticker, and good pictures of the carb and the engine compartment. There are people on here who can help you get most of it hooked back up.

 

 

Good call on the trans vacuum
Dave ----