1996 GMC Sierra Upper intake gasket replaced.

DAZEDNCONCFUSED

MEMBER
1996 GMC SIERRA
5.7L
V8
4WD
AUTOMATIC
205,150 MILES

I replaced my upper intake gasket. Now when I try to start it, the starter does its job, but the crankshaft will not budge. The truck has been sitting for a week. Also when I stop trying to start it, gas comes out somewhere from the bottom end. Help!

5 Replies

JACOBANDNICKOLAS

MECHANIC
109,896 POSTS

Is one of the cylinders filling with fuel? If you remove the spark plugs, will the crank turn then?

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Monday, May 18th, 2015 AT 8:48 AM

DAZEDNCONCFUSED

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4 POSTS

Haven't thought about that. Will let you know shortly.

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Monday, May 18th, 2015 AT 8:54 AM

DAZEDNCONCFUSED

MEMBER
4 POSTS

Cylinders 1, 4, and 5 had fuel covered plugs, crankshaft still won't do anything.

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Monday, May 18th, 2015 AT 9:13 AM

DAZEDNCONCFUSED

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4 POSTS

Okay, took a torque wrench to the crank. It moved and shot out about a half cup of fuel from cylinder 6.

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Monday, May 18th, 2015 AT 11:37 AM

JACOBANDNICKOLAS

MECHANIC
109,896 POSTS

That was the problem. It caused hydrostatic lock. Either the injector is stuck and dumping fuel, or the regulator is not restricting the fuel pressure.