#41  
Old 09-26-2020, 05:14 AM
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dataway dataway is offline
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Forget about the compression and drive it It will let you know if anything else is wrong. Glad it turned out ok.

  #42  
Old 09-26-2020, 10:18 AM
supersport#69 supersport#69 is offline
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Agreed but curiosity might get the best of me .i just want to know if any compression came back after the cylinder started working correctly.
On the other hand maybe I shouldn’t know.

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Old 09-26-2020, 11:31 AM
supersport#69 supersport#69 is offline
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I took a short video of starting it yesterday but I can’t get it to upload.

  #44  
Old 09-26-2020, 12:28 PM
"QUICK-SILVER" "QUICK-SILVER" is online now
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Quote:
Originally Posted by supersport#69 View Post
I took a short video of starting it yesterday but I can’t get it to upload.
Need to put it on something like youtube and post a link.

Clay

  #45  
Old 10-17-2020, 09:29 PM
supersport#69 supersport#69 is offline
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I bought some Octane Supreme and have driven it a few times. So far no smoking and not missing.

Even though it is running ok I feel like I want to go ahead and have the valve job for my peace of mind. A local shop wants $260 for both heads plus $40 each to resurface them, plus extra for parts needed.

Im just going to have them done as original with no 3 angle or modifying.

Any advice? With the motor never being rebuilt I’m semi nervous that freshly rebuilt heads might put pressure on bottom end.

With 68k original do I need to worry about only rebuilding heads? Any head gasket advice?

  #46  
Old 10-20-2020, 12:25 PM
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Those big engines have enough torque that they can hide all kinds of internal issues. I had a 69 Judge decades ago, more or less stock car but the original engine had been replaced with a 74 bone stock 455 4 bbl. The car had a 4 speed and 3.23 (it had AC) and it drove and idled fine. The engine wasn't particularly strong but I just blamed that at the time on it being a smogger low compression engine. It had obviously never been opened.

I came across a nice set of 71 GTO 400 heads (96) and intake so I figured I'd pull the 455, refresh it and and add those heads and intake which would give me a nice mid 9's compression ratio and better ports than the stock 1974 heads. To my surprise that still nice running 455 had broken rings in all 8 cylinders, a few broken valve springs, a nearly stripped clean nylon timing gear and 4 nearly flat lobes and several more worn lobes. And yet it had started, idled and ran fine for years.

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  #47  
Old 10-20-2020, 12:47 PM
supersport#69 supersport#69 is offline
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I sure hope that’s not my case!

In that case I’d be towing it home with heads off and saving money I guess.

I’m banking on it being an exhaust valve that’s burnt. Can you tell anything else about internals with heads off or gamble?

  #48  
Old 10-20-2020, 12:51 PM
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With the heads off (engine in the car I assume) you can visually inspect the cam lobes, lifters etc.

Also at this point you’d be wise to check the timing gears and chain since you’ve already drained the antifreeze.

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1969 LeMans (2dr & 4dr Hardtop and a Cvt)
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1969 Ventura 2 Seat Wagon
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  #49  
Old 10-20-2020, 01:41 PM
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Timing gear has been replaced. We saw the replacement when we did a new rear main seal and pan gasket.

  #50  
Old 10-21-2020, 08:33 AM
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Greg Reid Greg Reid is offline
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Prepare yourself for mission creep if you pull the heads. Not saying you shouldn't or that it would be a bad thing but just be prepared...You will wind up doing much more I bet.

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  #51  
Old 10-21-2020, 10:28 AM
supersport#69 supersport#69 is offline
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I am very nervous about that outcome. However I don’t know how else to attack the situation. If I don’t do it now it might run fine for x amount of time but it’s basically disabled right now.
Depending on the compression tester I’ve seen between 95-110 on the cylinder in question and never tested the other side of the motor (afraid to really)
Plus it’s not painted black yet so better now with primer to avoid another issue.
I’d like to think the I’m lucky and it’s a piece of carbon blocking the valve from seating all the way but nothing has gone that way yet.

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