Vacuum Question 87 351
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Joined: Aug 2000
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Vacuum Question 87 351
Posted this earlier but got no response, so here goes again. I just installed a re-rebuilt motor after much heart ache with the previous rebuild...lasted 8K. To top it off, the outfit (according to Ford dealer) that had rebuilt and installed the motor got all the emissions and vacuum lines wrong (or broke them, along with a few other expensive items-don't ask) so I'm kinda working in the dark. This time I numbered all the vacuum lines, pulled the motor, had it rebuilt by a reputable shop, and installed it myself. BUT...what kind of (and where to)vacuum do I need to make this EGR valve work? Its on an 87 Bronco 351 auto, 4bbl Holley. Chilton, Haynes, and ALLDATa show this motor but only with a TFI ignition. Mine is a Duraspark and don't show similar vacuum connections very well. ALSO, I ran the PCV and brake booster line back to where they had it (front of carb) and the result: when I step on the brake the engine idle increases and idle seems low, about 500rpm. Suggestions? I'm so close to resolving this year-long nightmare...and yet so far. Any help is, of course, appreciated. Thank you.
Your is haste,
Skippy
Your is haste,
Skippy
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Joined: Jun 1999
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From: Durham
Vacuum Question 87 351
Well, I can check my truck when I get a chance, but the simple solution for the EGR is to first put the smallest orifice washer in the base of the EGR available (if you're getting a new EGR valve). Then run from the EGR port to a thermal switch that would normally screw into the top of your thermostat housing. Finish this vacuum run by connecting between your thermal switch and a vacuum source on the base of your carb. I got the highest temp thermal switch I could from Advance Auto. This means that the EGR will not function until the temperature reaches the switch temp. There are other vacuum switches that you could run the EGR through, but that setup works fine on mine.
Your vacuum for the power brakes should come off of the back of the carb at the base and the PCV should dump to the front of the carb. The PCV will actually have unburnt gases that will dump back through the manifold to burn again. You can also hook the brake boost off a direct port off the manifold.
'82 F150 2WD w/351W (orig 300 I6)
Slik
Your vacuum for the power brakes should come off of the back of the carb at the base and the PCV should dump to the front of the carb. The PCV will actually have unburnt gases that will dump back through the manifold to burn again. You can also hook the brake boost off a direct port off the manifold.
'82 F150 2WD w/351W (orig 300 I6)
Slik
