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sprinkles08, ASE Certified Technician
Category: GMC
Satisfied Customers: 22653
Experience:  ASE Master and Advanced level certified. Factory trained with 15 years dealership experience
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After I replaced the head gasket and now the car won't

Customer Question

After I replaced the head gasket and now the car won't start
Submitted: 1 year ago.
Category: GMC
Expert:  Matt replied 1 year ago.


can you tell me the make, model , year and engine size of the vehicle please ?

also have you tried doing a compression test across all cylinders ? as they should all be within 10-15 psi of each other

Customer: replied 1 year ago.
2003 Izusu npr hd 4.8l diesel
Customer: replied 1 year ago.
Good compression
Expert:  Matt replied 1 year ago.


Ok in that case I'd ask are all the compression figures very close to each other as if you have a couple of low figures then this would indicate the cam timing is out - which can then be the issue of not starting

it’s also worth considering fitting a new fuel filter as if only slightly blocked this can lower fuel supply pressure and choke the main pump, the pump will be more sensitive to this when its cold as diesel thickens considerably with low temperatures.

Customer: replied 1 year ago.
This truck was running perfect just because mixing oil and antifreeze, we decided to replace the head gasket, the radiator and the reservoir.
I missed the marks then I broke three rockers
My question is how do I set up the marks?
Do I need remove the head again?
How do I get a tdc?
I'm not a diesel mechanic anymore
Expert:  Matt replied 1 year ago.


I don't have the timing data for this engine so I'll opt out and open it back up to others

good luck

Expert:  sprinkles08 replied 1 year ago.

Hello and welcome to JustAnswer!

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