cam & timing chain install question
#1
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cam & timing chain install question
Background:
Owned a few 22RE's here and there with limited mechanical experience (alternators, radiator installs, etc.) and a weak understanding of valve timing. I am in the process of replacing a head gasket on a 1986 Toyota 4Runner 22RE and decided to install a timing chain kit as well. I sent the head to a machine shop - came back with no concerns from the shop with the cam not at the correct position (didn't notice it at the time) and all valves were closed prior to installation. Got the head gasket and head on and noticed the cam peg (key?) was at 9 o'clock after installation. I attempted to turn it clockwise by hand to get it to 12 o'clock but there is tension that prevents movement. I stopped because I do not want to bend a valve. I loosened the rockers thinking that would give me some wiggle room but there is still tension on the cam. Cylinder #1 is at TDC. For successful timing chain installation, my understanding is that the cam key (mine has a peg that the cam sprocket sits on) needs to be at 12 o'clock along with the crank key - install sprockets, chain and guides with links matching the and you're done.
My questions:
Because I turned the cam before loosening the rockers - did the valves move?
After I loosened the rocker assembly do the valves go back up because of the springs?
I can I test to reassure myself that everything is timed properly with the head on?
Is it possible to tell if I am on a compression stroke or exhaust stroke & does it matter?
Sorry for all the questions, I just want to be sure I don't screw up this engine - the wife will be livid!
Thanks in advance! This is how the engine sits now.
Owned a few 22RE's here and there with limited mechanical experience (alternators, radiator installs, etc.) and a weak understanding of valve timing. I am in the process of replacing a head gasket on a 1986 Toyota 4Runner 22RE and decided to install a timing chain kit as well. I sent the head to a machine shop - came back with no concerns from the shop with the cam not at the correct position (didn't notice it at the time) and all valves were closed prior to installation. Got the head gasket and head on and noticed the cam peg (key?) was at 9 o'clock after installation. I attempted to turn it clockwise by hand to get it to 12 o'clock but there is tension that prevents movement. I stopped because I do not want to bend a valve. I loosened the rockers thinking that would give me some wiggle room but there is still tension on the cam. Cylinder #1 is at TDC. For successful timing chain installation, my understanding is that the cam key (mine has a peg that the cam sprocket sits on) needs to be at 12 o'clock along with the crank key - install sprockets, chain and guides with links matching the and you're done.
My questions:
Because I turned the cam before loosening the rockers - did the valves move?
After I loosened the rocker assembly do the valves go back up because of the springs?
I can I test to reassure myself that everything is timed properly with the head on?
Is it possible to tell if I am on a compression stroke or exhaust stroke & does it matter?
Sorry for all the questions, I just want to be sure I don't screw up this engine - the wife will be livid!
Thanks in advance! This is how the engine sits now.
#2
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follow up comment:
when the rocker assembly is installed with the head bolts torqued (i used 65 ft. lbs.) it puts pressure on the valves which may account for the tension I am feeling. If this is the case the valves should be in the correct position when the cam is at 12 o'clock. can you damage the valves by turning the cam by hand with the sprocket if the crank is not turning in sync? i dont really work out or anything so I'd say my strength is sub par at best.
when the rocker assembly is installed with the head bolts torqued (i used 65 ft. lbs.) it puts pressure on the valves which may account for the tension I am feeling. If this is the case the valves should be in the correct position when the cam is at 12 o'clock. can you damage the valves by turning the cam by hand with the sprocket if the crank is not turning in sync? i dont really work out or anything so I'd say my strength is sub par at best.
#3
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When you installed the head there should have been no tension on the rocker adjustment nuts .
..They should have all moved free .If there was it is possible you might have put valves into the top of the piston
The Rockers themselves were removed to recondition ??
Did the Machine Shop get the Cam Bearing caps in the wrong spot putting pressure on the Cam from no clearance on one of the ??
After torquing the headbolts if all is good once the cam gear is installed (easier to hold) you should be able to spin the cam very easy.
When the timing chain is off for what ever reason after the cam and crank gears are installed and the chain is on engine rotated by hand to check everything is good then one can adjust the valves.
..They should have all moved free .If there was it is possible you might have put valves into the top of the piston
The Rockers themselves were removed to recondition ??
Did the Machine Shop get the Cam Bearing caps in the wrong spot putting pressure on the Cam from no clearance on one of the ??
After torquing the headbolts if all is good once the cam gear is installed (easier to hold) you should be able to spin the cam very easy.
When the timing chain is off for what ever reason after the cam and crank gears are installed and the chain is on engine rotated by hand to check everything is good then one can adjust the valves.
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I took the rocker assembly to the machine shop and they said they didn't need it to just resurface and pressure check the head. I am not sure about the cam bearing caps - to my knowledge they look OK. How would I check the cam bearing caps position? I believe there was tension on the rocker arm assembly nuts... My friend has a borescope camera he is loaning me today so I will check all the cylinders thru the spark plug ports to look around. I think I should be able to tell where the valves are at with the camera. Hopefully that will tell me if I am OK or if I need to remove the head to repair anything. Ugh, hope I didn't screw anything up. I don't remember this being mentioned in the FSM - but this is my first shot at this.
I'll report back with what I find, thanks!
I'll report back with what I find, thanks!