Donor Help - Cobalt SS wont start but cranks - Thoughts?

BaltimoreHokie

Goblin Guru
Guys, tonight I tested the head a bit. I put water on the combustion part of the chamber, then sprayed compressed air into the intake ports. There was only a few bubbles on one valve, when I got the air gun really up against it. No water was able to escape into the ports as far as I could tell. As for the exhaust side, I still have my exhaust manifold on so it was pretty easy to stuff a rag pretty tight into the gap, then put an compressed air hose in with it. When testing these, every valve (8) had some bubbles. This was under more pressure since I was trapping the air in and pushing 100 or so psi into the manifold. Again, it didn't look like any water was leaking into the ports.

I think tomorrow I am going to set it on its side, fill the intake / exhaust ports with some type of fluid like brake cleaner and see if it makes its way out of the valve. Basically doing the reverse of what I did tonight, but without air.

Any idea of my test tonight indicates that the valves are bent?
 

PHerder

Well-Known Member
Some bubbles sound like carbon keeping the valves open just a little bit. If they were bent there would have been a path for the air to escape with more force.

I don't think you have bent valves at all. I bet if you CAREFULLY tapped on the valve stem to seat the exhaust valves, you would not have any air leakage. Remember that the exhaust valve is keeping the explosion IN and you are forcing air the other direction which just might push the valves open.
 

BaltimoreHokie

Goblin Guru
Some bubbles sound like carbon keeping the valves open just a little bit. If they were bent there would have been a path for the air to escape with more force.

I don't think you have bent valves at all. I bet if you CAREFULLY tapped on the valve stem to seat the exhaust valves, you would not have any air leakage. Remember that the exhaust valve is keeping the explosion IN and you are forcing air the other direction which just might push the valves open.
Well...Thats what I was hoping. But, working on it in my spare time makes me think about it plenty until the next time I work on things again. So I tend to over think things...
 

Karter2026

Goblin Guru
Some bubbles sound like carbon keeping the valves open just a little bit. If they were bent there would have been a path for the air to escape with more force.

I don't think you have bent valves at all. I bet if you CAREFULLY tapped on the valve stem to seat the exhaust valves, you would not have any air leakage. Remember that the exhaust valve is keeping the explosion IN and you are forcing air the other direction which just might push the valves open.
I agree! I would not be afraid to put it back on and use it
 

BaltimoreHokie

Goblin Guru
Well, as an update. I have the head on, intakes cleaned, replaced the balance chain and gear, put the new timing chain on. Timing the motor was really not all that tough. The hardest part was taking my time and getting the order correct. Which
I messed up...So, I had to buy new cam bolts because I went out of order and had to take the exhaust cam gear off after I had it installed.

I likely need to go back and touch up the intake ports again to see if I can get them a bit cleaner...put the front cover on then

I think I may need to pull the oil pan, I am afraid that parts of the chain guide may have broken off in there. Is it a pain to get the oil pan off?
 

dperkins

Well-Known Member
It's not hard, but it does require you to lift the engine off the ground. The oil pan has a seal that's very strong, so what I did was remove all the screws and then take a rubber mallet and find a corner to break it loose, then go to the other corner and do the same. Then it's off.
 

BaltimoreHokie

Goblin Guru
It's not hard, but it does require you to lift the engine off the ground. The oil pan has a seal that's very strong, so what I did was remove all the screws and then take a rubber mallet and find a corner to break it loose, then go to the other corner and do the same. Then it's off.
My engine is still in the car...so technically its off the ground. But, do you mean it needs to be supported from the top from an engine picker of some sort?
 

Briann1177

Goblin Guru
I think he was assuming you had your engine pulled out. You should only need enough clearance below for it to drop down.
 

dperkins

Well-Known Member
As long as it's off the ground and empty of oil, then you can remove the 10 or so bolts and smack it with a hammer to knock it off.
 

BaltimoreHokie

Goblin Guru
So...I got it all back together and I've got another issue.

First I tried to crank it over with the fuel pump fuse out. I read to do this to get fluids moving before you start it. It wouldn't crank at all. Just one click.

Just in case it was not working because of the fuse. I put it in. Tried to start and it did the same thing. I also have a fuel leak at the rail that I've got to fix.

The starter will not turn over at all. Even when I jumped the battery with a running vehicle just in case it was low battery.
I pulled the codes and it say P0627. Which is fuel pump control switch open. But I think I got it from the fuse being out the first time I cranked it.
Any ideas?
 

Karter2026

Goblin Guru
So...I got it all back together and I've got another issue.

First I tried to crank it over with the fuel pump fuse out. I read to do this to get fluids moving before you start it. It wouldn't crank at all. Just one click.

Just in case it was not working because of the fuse. I put it in. Tried to start and it did the same thing. I also have a fuel leak at the rail that I've got to fix.

The starter will not turn over at all. Even when I jumped the battery with a running vehicle just in case it was low battery.
I pulled the codes and it say P0627. Which is fuel pump control switch open. But I think I got it from the fuse being out the first time I cranked it.
Any ideas?
Check for ground and at starter and good power there also. Mine was corroded from sitting. Pulled starter cleaned terminals and loosen and cleaned ground cable worked fine after that.
 

Briann1177

Goblin Guru
I would double check the battery again. If the battery is toast, I'm pretty sure you can't start a vehicle with just jumper cables. The battery still needs to have some life in it.

Hook a charger up or have it load tested at an auto parts store.
 
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Briann1177

Goblin Guru
And yes that P0627 code is related to the fuel pump relay/fuse. If the ECM doesn't receive a feedback voltage from the fuel pump circuit it will throw that code. You can clear it manually or it will clear automatically.
 

BaltimoreHokie

Goblin Guru
I've had it charging for a while then on a running car for a while as well. My multimeter is reading that it's good. I did look and the starter does look somewhat corroded I tried to brush them off without removing it. It also is not dimming or anything when I turn the key over like it's low. I swapped the relays under the hood just in case that was it. No help

When I turn the key it's not even trying to turn over. I'll have to take the starter off and clean it and do a few tests on it but I don't have time tonight.

Other than the corrosion any ideas ?
 

Briann1177

Goblin Guru
An unloaded voltage reading can be misleading. It can read good sitting there but not start up.

Measure the voltage when cranking for several seconds. If it drops below around 10 volts or so, you should buy a new one.
 

Waterdriver

Goblin Guru
Sounds like the issu is the starter solenoid. Small canister shaped device on top of starter. That's what will make the loud click when you turn the key to start the car.
Disconnect power, remove and clean wire connections at the solenoid.
Re-connect battery and try starting again.
If it's still not starting remove the solenoid. Most likely rusted, corroded and or dirty and will not slide it's housing. Or solenoid has failed.
 

ctuinstra

Goblin Guru
If the lights don't dim in the slightest or the voltage doesn't drop, it's not even getting any voltage to the starter. I agree with Waterdriver that the starter solenoid could be the trouble. I know on mine when I went to take the starter cable off the starter, all the plastic crumbled and it fell apart. Another member on here also had the same problem with the starter falling apart. It could be yours is in bad shape and not making contact. Take the stater off and hook it straight to the battery to see if it works. You will need to ground the bolt holes of the starter and then jump 12V positive to the small nut and the large nut (hook the large terminal first and then put 12v on the small one to activated it).
 
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