i have 76 chevy 350 dies when put in gear? Help anyone?

**snowbrdr686** · 08-24-2009, 03:48 PM

i have a 76 gmc high sierra 4wd has 350 with holley 600cfm carb. the truck runs good when in park or nuetral but within seconds of putting into reverse or drive she bogs dwn and dies.. any information is much appreciated.. either email me at dean1edgeplyr@aol.com or post back.. prefer the email cuz don't know how much ill be able to check up on here.. thanx

**unplugged** · 08-24-2009, 09:12 PM

Sounds like a vacuum leak, but you'll have to do a little more digging to be sure. Fuel pressure could be low, and a clogged cat could also be possible. (If your truck has a cat) Just once I ran into a case where the inner wall of the muffler pipe collapsed and clogged the exhaust.

To test for a vacuum leak, remove the air cleaner and cup your hands over the carb slowing increasing how much you choke off the air supply. If the idle increases it usually indicates a leak. Spraying a little water around the throttle shafts, base gasket, intake gasket can help isolate the leak.

Test the fuel pressure with a gauge.

A DIY test of a clogged exhaust would be to disconnect it. (your neighbors will love the sound)

**lancer** · 08-24-2009, 09:32 PM

what kind of cam shaft is in the motor? my old malibu with a bigger cam and an automatic would idle great in park and neutral but when you put it in gear it would fall on its face unless you brake/gas at the same time. only way we could fix was idle up in gear which would make park idle really high. i ended putting a different cam in it.

**snowbrdr686** · 08-29-2009, 11:00 AM

Well thanx for the information people.. i ended up having to find TDC again.. was maybe a tooth or two off.. but now she starts up drives great except for a minor problem with the 3" headers hitting the front driveshaft.. left a good grove in it but not to bad grinding dwn header clamp

**unplugged** · 08-29-2009, 06:31 PM

Originally Posted by snowbrdr686

Well thanx for the information people.. i ended up having to find TDC again.. was maybe a tooth or two off.. but now she starts up drives great except for a minor problem with the 3" headers hitting the front driveshaft.. left a good grove in it but not to bad grinding dwn header clamp

Glad you got 'er running again.

When it comes to the internal combustion engine you gotta have:

1. Air
2. Fuel
3. Spark
4. Timing

Not much magic to it, just a little hard to troubleshoot once and awhile.