97 Rocker Valve Adjustment
#81
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Join Date: Oct 2014
Location: North Central Indiana
Posts: 3,052

He's got the valve covers off should be easy to find TDC when it closes both valves and goes for the compression stroke. Just find the correct spot with the piston up. As nothing has changed in the valvetrain the mark should be correct then.
Could actually be metric. I know that the 1st gen used replacement studs with an M10 thread. So it could be 17 or 19 mm wrench or socket as well. May need to get a hold of a manual.
Anybody in the forum got a 1997 one?
Could actually be metric. I know that the 1st gen used replacement studs with an M10 thread. So it could be 17 or 19 mm wrench or socket as well. May need to get a hold of a manual.
Anybody in the forum got a 1997 one?
#82
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Join Date: Mar 2017
Location: Tulsa, OK
Posts: 220

Ok the size socket for the screw in rocker studs is 15mm, I just pulled out the stud today and replaced the studs, but I need to torque them. What's the torque specifications for these rocker studs ? I also Teflon taped the threads (pic)
#83
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Thread Starter
Join Date: Mar 2017
Location: Tulsa, OK
Posts: 220

He's got the valve covers off should be easy to find TDC when it closes both valves and goes for the compression stroke. Just find the correct spot with the piston up. As nothing has changed in the valvetrain the mark should be correct then.
Could actually be metric. I know that the 1st gen used replacement studs with an M10 thread. So it could be 17 or 19 mm wrench or socket as well. May need to get a hold of a manual.
Anybody in the forum got a 1997 one?
Could actually be metric. I know that the 1st gen used replacement studs with an M10 thread. So it could be 17 or 19 mm wrench or socket as well. May need to get a hold of a manual.
Anybody in the forum got a 1997 one?
#86
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Join Date: Oct 2014
Location: North Central Indiana
Posts: 3,052

ok so I need to torque the rocker nuts to 20lbs on each when the piston is TDC/All the way up on compression stroke. Correct me if I'm wrong, but 1 complete revolution of the harmonic balancer is considered a "stroke" and during that revolution/stroke and can be either intake or exhaust.. Right ? And if so, how can I tell its on the right/compression stroke on each piston ? By simply watching the rods on each cylinder go all the way up ? Rods all the way up, is closed right ?
the rest of this is only for dropping the distributor in correctly.
One complete rev of the balancer is 2 strokes, as the piston goes up and down during this time. In a 4-stroke engine each cylinder fires every 2 revolutions of the crankshaft. On this V-6, a different cylinder fires every 1/3 turn. 6 x 1/3 = 6/3 = 2 revolutions and you are back to TDC#1. When the timing marks on the balancer are lined up, you have a 50:50 chance of being on TDC#1. The other possibility is TDC#4.
When a cylinder fires, both of the valves are closed so it build compression right before. So if you have the valve covers off, the valves for #1 should not be moving as the marks come into alignment. Otherwise you can also use the finger over the spark plug hole to tell when you are getting compression.
Good luck! Ask about anything that you don't understand.
Last edited by LesMyer; 06-22-2017 at 02:15 PM.
#87
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Join Date: Mar 2017
Location: Tulsa, OK
Posts: 220

No it doesn't matter at all where the piston is when putting the rockers on - just torque the rocker nuts to 20 ft lbs wherever the engine is at - there is no valve adjustment.
the rest of this is only for dropping the distributor in correctly.
One complete rev of the balancer is 2 strokes, as the piston goes up and down during this time. In a 4-stroke engine each cylinder fires every 2 revolutions of the crankshaft. On this V-6, a different cylinder fires every 1/3 turn. 6 x 1/3 = 6/3 = 2 revolutions and you are back to TDC#1. When the timing marks on the balancer are lined up, you have a 50:50 chance of being on TDC#1. The other possibility is TDC#4.
When a cylinder fires, both of the valves are closed so it build compression right before. So if you have the valve covers off, the valves for #1 should not be moving as the marks come into alignment. Otherwise you can also use the finger over the spark plug hole to tell when you are getting compression.
Good luck! Ask about anything that you don't understand.
the rest of this is only for dropping the distributor in correctly.
One complete rev of the balancer is 2 strokes, as the piston goes up and down during this time. In a 4-stroke engine each cylinder fires every 2 revolutions of the crankshaft. On this V-6, a different cylinder fires every 1/3 turn. 6 x 1/3 = 6/3 = 2 revolutions and you are back to TDC#1. When the timing marks on the balancer are lined up, you have a 50:50 chance of being on TDC#1. The other possibility is TDC#4.
When a cylinder fires, both of the valves are closed so it build compression right before. So if you have the valve covers off, the valves for #1 should not be moving as the marks come into alignment. Otherwise you can also use the finger over the spark plug hole to tell when you are getting compression.
Good luck! Ask about anything that you don't understand.
The pic of the upper intake is with the damaged gasket, most bolts on that side were loose. What would cause that damage ? And with that much air getting in from the upper intake, could that cause a no start too ?
Last edited by Tynan Tha Real Dill; 06-22-2017 at 05:34 PM.
#88
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Thread Starter
Join Date: Mar 2017
Location: Tulsa, OK
Posts: 220

OK, I got everything put back together and started it up. It ran about a minute, then made a popping noise and died. Checked around the engine and I had a little smoke coming from the throttle body. Waited some time, then I got my video camera ready, started recording, and I got this ....(YouTube video link). Starts up slow, then idle RPM shoot up to near 1500, then as idle RPM decreases, the engine stalls. Notice the light knocking sound too ?? What does that sound like ??
https://youtu.be/h6f-ZFydPes
https://youtu.be/h6f-ZFydPes
Last edited by Tynan Tha Real Dill; 06-23-2017 at 12:24 AM.
#89
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Join Date: May 2017
Location: North Dakota
Posts: 338

OK, I got everything put back together and started it up. It ran about a minute, then made a popping noise and died. Checked around the engine and I had a little smoke coming from the throttle body. Waited some time, then I got my video camera ready, started recording, and I got this ....(YouTube video link). Starts up slow, then idle RPM shoot up to near 1500, then as idle RPM decreases, the engine stalls. Notice the light knocking sound too ?? What does that sound like ??
https://youtu.be/h6f-ZFydPes
https://youtu.be/h6f-ZFydPes
That engine sounds like it has quite a few issues. First The way it cranks sounds like it may have jumped a tooth on the timing gear set or the distributor is a tooth off. Second that loud knocking sounds very much like a knock from the bottom end and Third it sounds like the valve train is rattling. Did you have any oil pressure when that video was made? I know earlier in the thread you talked about taking the pan off and checking the bearings. What bearing did you check and are you sure you put the bottom end back together correctly.
I would honestly look for another engine with how that one sounds.
Last edited by ChuckNTruck; 06-23-2017 at 01:09 AM.
#90
Junior Member
Join Date: May 2017
Location: North Dakota
Posts: 338

When you spun the engine and broke the screwdriver tip in cyl 1, did the screwdriver tip force the engine to stop turning? Were you using the starter to turn the engine over or turning by hand?
I am wondering this because if the engine was spinning with enough force and that piston was stopped it could have bent a rod and the knocking sound is that rod contacting something.
I am wondering this because if the engine was spinning with enough force and that piston was stopped it could have bent a rod and the knocking sound is that rod contacting something.





