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1969 Opel Gt 1.9 Automatic
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Discussion Starter · #1 ·
Hi guys so I have been woring on the GT lately. It isn't running perfect but it's running pretty good. I know that the valves are loud and annoying in Opels but my grandpa thinks they might be too loud and we want to adjust the valves so the engine will run good(even with a vacuum leak) and so te valve noise might go down. Also who knows when the last time those valves were adjusted. It is a solid lifter engine because it is a 1969. So does anyone know how to adjust them?

Thanks Sam
 

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Your grandfather might agree with my Old Man's advice to me sixty years ago that ":...it's better to hear them than burn them." You may also find, as I did with mine, that one or two valves may be too tight, and setting them to spec will make the engine run much smoother. A good idea before you set to work adjusting the valves will be to do a compression check.
 

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Detritus Maximus
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Motors and heads got swapped around a lot, so confirm you still have a solid lifter motor!
 
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Just Some Dude in Jersey
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I loved the ritual of adjusting my '70's solid lifters. I used the car a lot and drove 12,000 miles a year for 18 years. I adjusted the valves once a year or whenever I started hearing them tap too much. The gap is .012. Even when perfect the engine will sound like a typewriter. I didn't have a great way to tell if the cam lobe was pointing down, so I would just rotate the engine and stick my finger in the holes on the driver's side of the rocker studs to feel and see that the lobe for the rocker I was adjusting was pointing 180* down, then just work my way down the line. Better to be a fraction loose(.013+) than too tight(.011-). Sometimes you'll have a rocker nut that keeps working loose and you repeatedly hear a valve tapping and have to keep readjusting the same valve. Generally, you'll find that you don't have to adjust hardly of them during your yearly check. Make sure you are using oil with zinc additive(ZDDP) to prevent lifter/cam wear.
 

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1969 Opel Gt 1.9 Automatic
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Discussion Starter · #6 ·
Thanks for all the help! I will definently work on them the next time I go over there!
 

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I loved the ritual of adjusting my '70's solid lifters. I used the car a lot and drove 12,000 miles a year for 18 years. I adjusted the valves once a year or whenever I started hearing them tap too much. The gap is .012. Even when perfect the engine will sound like a typewriter. I didn't have a great way to tell if the cam lobe was pointing down, so I would just rotate the engine and stick my finger in the holes on the driver's side of the rocker studs to feel and see that the lobe for the rocker I was adjusting was pointing 180* down, then just work my way down the line. Better to be a fraction loose(.013+) than too tight(.011-). Sometimes you'll have a rocker nut that keeps working loose and you repeatedly hear a valve tapping and have to keep readjusting the same valve. Generally, you'll find that you don't have to adjust hardly of them during your yearly check. Make sure you are using oil with zinc additive(ZDDP) to prevent lifter/cam wear.
The gap varies with the type of cam in the engine. I have a combination cam and it calls for .018”
 

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Just Some Dude in Jersey
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I'm not criticizing your choice to follow that advice you were told, but that advice makes no sense at all to me. I drove a Combo cam for 225,000 miles and always set the gap at .012. Any looser and you would get a valve tap. You don't want a valve tap, it creates wear and tear and a delay in your valve timing. I can't think of any logical reason to leave a gap that would cause a tap regardless of what kind of cam you have. But, I'll listen to logical explanations to leave your rockers loose on a solid lifter engine with a cam. :)
 

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I'm not criticizing your choice to follow that advice you were told, but that advice makes no sense at all to me. I drove a Combo cam for 225,000 miles and always set the gap at .012. Any looser and you would get a valve tap. You don't want a valve tap, it creates wear and tear and a delay in your valve timing. I can't think of any logical reason to leave a gap that would cause a tap regardless of what kind of cam you have. But, I'll listen to logical explanations to leave your rockers loose on a solid lifter engine with a cam. :)
I’m not sure why the combination cam requires more valve clearance, but here’s the reference from Isky.
As an FYI, Gordo's contention of a "big cam" NOT requiring a larger valve lash (more clearance) has been thoroughly rebuked by engine-heads as reputable as our own RallyBob. Follow the cam manufacturer's lash specification unless you are smarter than RallyBob... ;)
 
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