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Old 12-02-2014, 01:12 AM   #41
Bob Johnson
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Default Re: My new engine starting nightmare in Seattle. Touring motor.

Here is a graph of the valve lift. As you can see there is a slight overlap of the exhaust and intake valves when the exhaust valve is closing and the intake valve is opening. This overlap occurs when the piston reaches top dead center. So you can rotate the engine until the piston is just about at the top of the stroke. Since the crankshaft rotates 2 revolutions for each 1 revolution of the camshaft there are 2 positions that the valves will be in when the piston is a the top of the cylinder. The first case is when the spark plug is ready to fire. In this first case the intake valve will have just closed and the exhaust valve will have been close for about one crankshaft revolution. If you then rotate the engine one revolution you will see the exhaust valve start opening as the piston comes to the bottom of the cylinder. As the piston moves up the exhaust valve will fully open and then close as the piston reaches the top of the cylinder. At this time the intake valve will start to open. If your valves are not behaving like this then you camshaft timing is not correct.


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Old 12-02-2014, 10:58 AM   #42
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Default Re: My new engine starting nightmare in Seattle. Touring motor.

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Originally Posted by tbirdtbird View Post
I'm with Tom W on checking the cam timing....you said "I indexed the cam"; how certain are you of what was done? Especially since you say "It almost feels like it is sucking in? " at the exhaust

We can argue all day whether to check compression hot or cold. However, cold there should be very decent compression with this 7:1 head.

Have you worked on engines before this?
Thank you Tbird...

" HITCHHIKER ".........verify the cam timing,....are they both in the correct place?
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Old 12-02-2014, 02:26 PM   #43
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Default Re: My new engine starting nightmare in Seattle. Touring motor.

I have not done much engine work before. I actually wasn't the one to index the cam,it was my uncle. He's forgotten more than I will ever know....

then I did the valve adjustment. I know he wants me to figure this out on my own, and I would like to, so I haven't asked him for help yet.

Will check the valve timing.

Also I should add that the lifters are adjustables. Not A lifters.
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Old 12-02-2014, 04:30 PM   #44
Tom Wesenberg
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Default Re: My new engine starting nightmare in Seattle. Touring motor.

You have to be careful when timing the gears because some books show the cam gear in alignment with a line straight up from the left side of the keyway, but it is correct when it's lined up to the RIGHT side of the keyway.
This is easy to remember, RIGHT is RIGHT
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Old 12-02-2014, 06:15 PM   #45
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Default Re: My new engine starting nightmare in Seattle. Touring motor.

Twice bitten twice shy. I partially rebuilt two model a engines and both times starting was difficult and both tomes it turned out to be the oil rings. Even though everything measured out 60 over the rings were too tight in the cylinders. Make sure the engine can be turned with a torque wrench at 35 pounds with no compression. Take the plugs out. There is a big story I could tell as to why this happened but I'm keeping it short.
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Old 12-12-2014, 08:17 PM   #46
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I have confirmed that my valves are not sealing when closed on the compression stroke.

I am going to adjust them right now, wish me luck.
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Old 12-12-2014, 09:25 PM   #47
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Default Re: My new engine starting nightmare in Seattle. Touring motor.

Good luck Matt
go slow and you will get it
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Old 01-19-2015, 12:20 AM   #48
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Default Re: My new engine starting nightmare in Seattle. Touring motor.

whatever became of this project? So often we post our brains out then never get feedback......
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Old 01-19-2015, 01:58 AM   #49
Tom Wesenberg
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Default Re: My new engine starting nightmare in Seattle. Touring motor.

Quote:
Originally Posted by Hitchhiker View Post
I have not done much engine work before. I actually wasn't the one to index the cam,it was my uncle. He's forgotten more than I will ever know....

then I did the valve adjustment. I know he wants me to figure this out on my own, and I would like to, so I haven't asked him for help yet.

Will check the valve timing.

Also I should add that the lifters are adjustables. Not A lifters.
If you never did this before, I would think your grandfather would want to be there to teach you or at least watch to make sure the correct clearance is given each valve.
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