Timing chain motor trashed?
Went to pull a part today (you pull it) engine with 106,000 miles no start jumped time. Motor with 135,000 showed signes of a blow or going head gasket and milky oil. Engine 3 146,000 miles had fuel service at 110,000 oil was a little brown normal from the age and not black. 4.5 hours alone and now it’s sitting at well in my house. So new question is.. is there a way to tell if the timing chain has been changed? Or should I just take the safe route and change it anyway? I’m already changing the valve cover and I still have to get the balancer pull bolt out. And FYI pulling the motor out the top is a royal pain in the arse at least on the cobalt it is. I got all sensors and plugs just to have backups. Total cost so far $207.00 if anyone has any ideas of preventative stuff to do to this motor please tell me so I can do it now. Thank you guys for all your help one again you guys saved me with knowledge.
Change the timing and balance shaft chains and guides, I suggest the water pump and thermostat as well, it’s much easier now.
I always install the sensors from the OEM motor and keep the donor motor ones for spares
I always install the sensors from the OEM motor and keep the donor motor ones for spares
I got side triacked and forgot to post did digging on the head this morning bent valves spotted 2 for sure valve spring down and followers flopping on the cam both intake valves 2 different cylinders. The impact was probably the shake I felt when it fired one time on that startup when it jumped time I can roll the timing chain by hand off the sprockets bore scope will be here in the morning with a mirror and I will triple check it. Needed a solid backup plan either way though.
Just enough to bend the top hat. That’s the only pics I took that was enough to warrant the swap. I was shaking and couldn’t get a good pic of the top hat bent. It’s a shame looked pretty clean otherwise.
Okay so my plan is new water pump new chains and sprockets thermostat plugs. So far the only differences is a nipple on the block for overflow compaired to hhr it being on the neck. I have to swap thermostat housings but I am having a hard time finding the gasket. Any one have a link by chance?
Okay so my plan is new water pump new chains and sprockets thermostat plugs. So far the only differences is a nipple on the block for overflow compaired to hhr it being on the neck. I have to swap thermostat housings but I am having a hard time finding the gasket. Any one have a link by chance?
Donbrew. Thank you I was getting a hair confused when I didn’t see them rectangle and didn’t see the note like yours has. Is there a brand of water pump you could recommend?
I have looked at the part stores and rock auto however I don’t feel secure in getting a “budget” water pump.
I found a couple deals on Cloyes chains and gears. I did take the water pump plate off and seen white or yellow paint on the chain however old style tensioner clearly a flat back style.
Pulled the plugs and scoped this one also some decent carbon build up. I think a few tanks of sea foam will clear that up. Plugs looked good and despite the carbon they burned clean and good color.
So far engine differances are that water port i have to plug and swap exhaust mainifolds the new one had Cali emissions. Kept all safety clips I could salvage. I still have to run the number on the fuel rail they look exact to me at a glance. I saved the fuel injector harness so I could just plug and play with it. Throttle body looks fair. I have to swap rear thermostat housings. I broke the cobalt one on the pull. That’s about all the updates I have as of now.
I have looked at the part stores and rock auto however I don’t feel secure in getting a “budget” water pump.
I found a couple deals on Cloyes chains and gears. I did take the water pump plate off and seen white or yellow paint on the chain however old style tensioner clearly a flat back style.
Pulled the plugs and scoped this one also some decent carbon build up. I think a few tanks of sea foam will clear that up. Plugs looked good and despite the carbon they burned clean and good color.
So far engine differances are that water port i have to plug and swap exhaust mainifolds the new one had Cali emissions. Kept all safety clips I could salvage. I still have to run the number on the fuel rail they look exact to me at a glance. I saved the fuel injector harness so I could just plug and play with it. Throttle body looks fair. I have to swap rear thermostat housings. I broke the cobalt one on the pull. That’s about all the updates I have as of now.


