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Discussion Starter #1
So this noise is coming from the engine compartment and I really cannot tell exactly where it is coming from. The noise was present prior to my recent valve adjustment. The noise seems to go away at higher revolutions or maybe because I cannot hear it over the higher RPM's. The noise started as a light click that would kind of come and go - now it is continuous, at idle. Any comments or observations are appreciated. Thanks.

 

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Opel Rallier since 1977
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In the later part of the video, the loud 'putt-putting' sounds like an exhaust leak on 1 or 2 cylinders, perhaps at the exhaust manifold flange where it bolts to the head, or perhaps at the connection from the exhaust manifold to the headpipe (the 2 pipe part of the exhaust), or even the exhaust to intake manifold connection. You can sometimes find such leaks by carefully poking your fingers near and around the exhaust connections and feel the hot leakage of exhaust gases.

There is also some light valve clatter, which is what you hear when things are revved up. That might get quieter with a slightly tighter valve lash setting.

  • Are the spark plugs tight?
  • Are all 6 of the manifold bolts tight?
  • When warmed up and driving around, does the engine run at a normal coolant temperature?
 

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Take off your radiator cap...you may have blown a head gasket...if so, it will bubble in the radiator...
 

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Discussion Starter #4
In the later part of the video, the loud 'putt-putting' sounds like an exhaust leak on 1 or 2 cylinders, perhaps at the exhaust manifold flange where it bolts to the head, or perhaps at the connection from the exhaust manifold to the headpipe (the 2 pipe part of the exhaust), or even the exhaust to intake manifold connection. You can sometimes find such leaks by carefully poking your fingers near and around the exhaust connections and feel the hot leakage of exhaust gases.

There is also some light valve clatter, which is what you hear when things are revved up. That might get quieter with a slightly tighter valve lash setting.

  • Are the spark plugs tight?
  • Are all 6 of the manifold bolts tight?
  • When warmed up and driving around, does the engine run at a normal coolant temperature?

  • Spark plugs are tight
  • All 6 manifold bolts tight - however will check for leaks as you suggested
  • The car is running cool as it has been
  • I had already decided to reset the lash to something a little tighter as I have noticed that it is a little harder to start and idles low around 56 insteed of 8 and almost stalls until it warms up so I assumed the lash was off - Perhaps I go from 18 cold to 16 cold??
  • Don't think I have blown the head gasket - no bubbles or oil in the radiator - just nice and clear
 

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Discussion Starter #6
If anything I would go looser on the valves...
Greetings Joel,
Received your last 2 comments about my recent video and the sound/sounds that my GT is currently making and appreciate your recommendations especially considering that you were an auto shop teacher for 30 years which means you have knowledge I can only dream about. Not sure if you saw the specifications of my engine but wanted to pass that along in hopes that you can give me a more definitive recommendation on the gap setting and why. The engine has around 2700 miles on it and is surrounded, pretty much, by all new components. Thanks for your help. Carl

Remanufactured 2.0L with custom head
Combo solid grind cam .430 lift 268 duration
.30 OS 2.0L pistons
1.72 chevy stainless steel intake valves
1.50 Chevy stainless steel exhaust valves
Dual valve springs, hardened valve seats

 

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Just Some Dude in Jersey
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I don't think an exhaust leak would affect the engine enough to make it run like that. It sounds like bad valve adjustment or a timing/spark related issue.

Loosening the valves is a good suggestion. I solid lifter engine with slightly too much lifter gap will run and sound just as perfect as a well-tuned perfect engine, but it will sound like a typewriter. I suggest backing all the valves off to 16-18 gap or more to assure that all the valves are closing completely. It sounds like you have a combination of multiple intake and exhaust valves not closing completely. Your timing might also be too advanced.

You can run your engine without the valve cover on. You have to make a sheet metal cover to enclose the timing chain and take a big old sheet and carefully surround the entire head and cover the engine and surrounding parts of the car and windshield to prevent micro-droplets of oil getting all over things. Be careful that the sheet won't get caught on the fan or catch fire touching the exhaust.
 

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No....its not a Buick....
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Timing chain slapping perhaps?
 
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