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Edit for more information about the car:
-Model Year: 2002
-Make/Brand: Infiniti G20
-Complete Model: Sport
-Engine/Transmission/4WD/2WD: 2WD, FWD
-Country (market) the car was sold in: USAI just replaced the valve stem seals. Put everything back together, torqued and timed using second to left crank mark (tried two other marks too, same result) 10 o clock intake sprocket timing mark and 12 o clock exhaust mark. Also counted the crank teeth. The motor gets stuck at a certain point.
Pretty much at a loss here, as I’ve exhausted my novice automotive skills and didn’t get anywhere with the engine today. Spent several hours timing it to OEM spec, then two other ways, as well as inspecting the tensioner and seeing if something had fallen down one of the spark plug holes. I fished the holes with a magnet and didnt catch anything.
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Did you put the cams in correctly, i.e. not reverse the intake and exhaust cams?
Worst case, remove the timing chain and cams (or turn them to where valves are fall fully closed) and try to turn the engine.
Make sure that when you are aligning your timing marks that the #1 cylinder is in TDC on the compression stroke. If it is at TDC on exhaust stroke then there will be piston-to-valve contact since the valves are open.
[quote=”ToyotaKarl” post=187975]Did you put the cams in correctly, i.e. not reverse the intake and exhaust cams?
Worst case, remove the timing chain and cams (or turn them to where valves are fall fully closed) and try to turn the engine.[/quote]
I’m thinking my best bet here is to remove the crank pulley and inspect the crank sprocket, possibly change out the front crank seal while I’m at it. The chain seems okay, not really sure I need to replace that.
Do you have any insight on removing the crank on an SR20 in the G20? I found some info, but I’d like to see if a more experienced person can provide a thorough walkthrough so I don’t mess anything else up.
[quote=”cap269″ post=187987]Make sure that when you are aligning your timing marks that the #1 cylinder is in TDC on the compression stroke. If it is at TDC on exhaust stroke then there will be piston-to-valve contact since the valves are open.[/quote]
Good time to learn something here. How can I tell when #1 is on the compression stroke? I assume when I see the valves move a certain way, but I honestly am not that learned yet on what that means, yet.
I’m glad I learned how to do valve stem seals, but think I was better off leaving this car at just a valve cover gasket replacement as I now have an out of time paperweight instead of a reliable fuel saver daily driver. LOL
To have cylinder 1 @ TDC in compression.
All valves need to be in their close positions, cam lobes off there lifters for the specific cylinderYou will also need to confirm the piston is at the top of its travel.
Easy way would be remove the spark plug, insert a long thin screw driver or metal rod.
Hand rotate the engine and watch the screw driver rise.
When it stops rising your at the top of the travel.I can not say as to how exactly setting TDC on # 1cylinder relates to the timing mark alignment for your specific engine..
Looks like I’ll be pulling off the head and seeing what’s really going on down in there. Appears to be a broken intake or exhaust valve.
My guess is that when my buddy and I reinstalled the valve spring with retainers, we somehow applied too much force to the valve and snapped it. Not quite sure if that’s common. We used a Lisle 36200 removal/installation tool for the job.
Need some advice from senior members here:
The motor has 209K miles. I just recently acquired it, was running great. Only attempted valve stem seals to learn how to do them and figured it was worth a shot to see if it fixed the problem of burning a quart of oil every 500 miles, as the previous owner stated. I actually used Castrol GTX High Mileage 10w40 and did a piston soak, and didn’t notice any significant loss of oil. Should have stayed put at that, but I decided to try to learn how to do valve seals anyway.
So:
1) Continue removing the head to replace the broken valve(s) and install a new head gasket and head bolts, along with any other knick knacks I encounter.
2) Buy a JDM motor with ~65K for $750 and re-seal the motor with new gaskets.
or 3) ???
Kind of stuck in a pickle. I hoped to get 250K miles out of the car before any significant repairs, like an engine or transmission swap, so I’m leaning toward replacing the valve(s) and installing a new head gasket and head bolts.
I only need it to drive to work and back, mostly highway miles.
Education and experience are valuable. When this repair is finished, you will have learned things, so the money is well spent. At this point, since you are questioning the integrity of the valve train, I would just take the head to a machine shop and let them recondition it. You’ll get it back in A-1 tip top shape, and then it’s just a matter of reinstalling it with new gaskets (and perhaps a new set of bolts, too). I would go this route over swapping the entire motor since you feel confident that the block and rotating assembly are good. Just make sure that when putting on the timing set that your timing marks are all lined up and that you’re on the right stroke, and that should be that.
[quote=”cap269″ post=188183]Education and experience are valuable. When this repair is finished, you will have learned things, so the money is well spent. At this point, since you are questioning the integrity of the valve train, I would just take the head to a machine shop and let them recondition it. You’ll get it back in A-1 tip top shape, and then it’s just a matter of reinstalling it with new gaskets (and perhaps a new set of bolts, too). I would go this route over swapping the entire motor since you feel confident that the block and rotating assembly are good. Just make sure that when putting on the timing set that your timing marks are all lined up and that you’re on the right stroke, and that should be that.[/quote]
Yeah, I decided to just push through and fix what I have. I did find a motor for $350 locally. I’m curious if refinishing a head will be about the same cost. I do know a good cylinder head shop in Orlando.
Learning is good, but to be honest, the best lesson I feel I learned is that if the car has over 200K miles and is running without a hitch, LEAVE IT BE and enjoy it. LOL
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