Valve adjuster squashed |
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Valve adjuster squashed |
nditiz1 |
Jun 29 2020, 02:45 PM
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#1
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Senior Member Group: Members Posts: 1,165 Joined: 26-May 15 From: Mount Airy, Maryland Member No.: 18,763 Region Association: MidAtlantic Region |
So doing a valve adjustment i found #3 intake to be very loose. I started to adjust and then found this. Why/how did this happen?
Also, why are my leakdown tests consistently 20% leaking through the case? Rings? I did it cold and the engine looks to be rebuilt from how clean the inside of the heads were. |
BillC |
Jun 29 2020, 03:05 PM
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#2
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Senior Member Group: Members Posts: 532 Joined: 24-April 15 From: Silver Spring, MD Member No.: 18,667 Region Association: MidAtlantic Region |
My guess is that you got a defective adjuster screw that wasn't heat-treated properly. It's unusual for one of those to peen over like that, especially if there's no other damage in the valve train. Maybe it got beaten up when the valve lash opened up a bit.
If the leakdown is through the case, then it probably is the rings. Could be that they haven't seated properly, or maybe they're cracked. I have a borescope for checking the cylinders, if you'd like to drive down and borrow it -- you could check for scoring on the cylinder walls. |
porschetub |
Jun 29 2020, 03:26 PM
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#3
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Advanced Member Group: Members Posts: 4,695 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
So doing a valve adjustment i found #3 intake to be very loose. I started to adjust and then found this. Why/how did this happen? Also, why are my leakdown tests consistently 20% leaking through the case? Rings? I did it cold and the engine looks to be rebuilt from how clean the inside of the heads were. The adjusters do wear,once the hardening has broken away you get your problem,this is often compounded by too much clearance. I never refit adjustment screws that are too worn,its just not worth it,you will need to check the end (tip) of the inlet valve isn't damaged which I fear might be the case. Try a compression test with the engine up to temp ,a cold air cooled engine takes up a fair amount with expansion,if your leakdown test is even 20% it will improve when hot so you should be fine. Good luck. |
nditiz1 |
Jun 29 2020, 04:00 PM
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#4
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Senior Member Group: Members Posts: 1,165 Joined: 26-May 15 From: Mount Airy, Maryland Member No.: 18,763 Region Association: MidAtlantic Region |
Thanks!
The valve had a slight knick on the edge, looks to be outside of the adjuster impact zone so I think we are ok. |
brant |
Jun 29 2020, 04:13 PM
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#5
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914 Wizard Group: Members Posts: 11,584 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
as an unknown (to you) motor
it might be worth doing the leak down test that can verify your valve seat is still making a good seal brant |
burton73 |
Jun 29 2020, 04:53 PM
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#6
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burton73 Group: Members Posts: 3,462 Joined: 2-January 07 From: Los Angeles Member No.: 7,414 Region Association: Southern California |
My guess is that you got a defective adjuster screw that wasn't heat-treated properly. It's unusual for one of those to peen over like that, especially if there's no other damage in the valve train. Maybe it got beaten up when the valve lash opened up a bit. If the leakdown is through the case, then it probably is the rings. Could be that they haven't seated properly, or maybe they're cracked. I have a borescope for checking the cylinders, if you'd like to drive down and borrow it -- you could check for scoring on the cylinder walls. I had a set of lifters that kept mushrooming because they where not heat treated. Sad story for me. They made good on new lifters but I had to split the case and rebuild on a 3,000-mile engine. Vales would go out of adjustment all the time. This was in 1978 Bob B |
nditiz1 |
Jun 29 2020, 05:36 PM
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#7
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Senior Member Group: Members Posts: 1,165 Joined: 26-May 15 From: Mount Airy, Maryland Member No.: 18,763 Region Association: MidAtlantic Region |
That stinks Bob.
So I put a good used one in its place. Torqued it back up and move o to cylinder 4. Im hoping what I found here was a rocker shaft nut and nothing more. The nuts on shaft 3 are copper, not the stock ones. I believe the PO said he had to fix a rocker on number 3 lets hope this is the only hardware that got left behind |
porschetub |
Jun 29 2020, 05:46 PM
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#8
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Advanced Member Group: Members Posts: 4,695 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
Thanks! The valve had a slight knick on the edge, looks to be outside of the adjuster impact zone so I think we are ok. Should be ok then...you dodged a bullet there,I would check the rest carefully if chipped or really worn you should replace them all ,they aren't very expensive. EMW sell them as far as I know. It's obviously not good the have hardened steel particles (ferrous metal ) in your oil...I would remove and check the oil strainer as a "just in case" and look for wear and damage to the rocker arm and pushrod of that cylinder. Good luck. |
porschetub |
Jun 29 2020, 05:55 PM
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#9
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Advanced Member Group: Members Posts: 4,695 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
That stinks Bob. So I put a good used one in its place. Torqued it back up and move o to cylinder 4. Im hoping what I found here was a rocker shaft nut and nothing more. The nuts on shaft 3 are copper, not the stock ones. I believe the PO said he had to fix a rocker on number 3 lets hope this is the only hardware that got left behind Shit that's not good,looks like the pushrod retainer spring hasn't been fitted properly and has chewed up your pushrods. I would tear down rocker gear on both side and do a full R&R with everything done right. |
RoadGlue |
Jun 29 2020, 08:07 PM
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#10
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Sonoma County Gear Head Group: Admin Posts: 2,033 Joined: 8-January 03 From: Santa Rosa, CA Member No.: 108 Region Association: Northern California |
Shit that's not good,looks like the pushrod retainer spring hasn't been fitted properly and has chewed up your pushrods. I would tear down rocker gear on both side and do a full R&R with everything done right. (IMG:style_emoticons/default/agree.gif) The pushrod wall material is pretty thick, but I'd always have a little voice in the back of my head questioning their integrity. It's just one of those parts that if it were to fail it would rain a lot of debris into the heart of your motor. |
porschetub |
Jun 30 2020, 01:17 AM
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#11
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Advanced Member Group: Members Posts: 4,695 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
Shit that's not good,looks like the pushrod retainer spring hasn't been fitted properly and has chewed up your pushrods. I would tear down rocker gear on both side and do a full R&R with everything done right. (IMG:style_emoticons/default/agree.gif) The pushrod wall material is pretty thick, but I'd always have a little voice in the back of my head questioning their integrity. It's just one of those parts that if it were to fail it would rain a lot of debris into the heart of your motor. The fitment of the spring retainer has to be right,they frequently get bent out of shape when removed or put on wrong,this needs to be sorted. Yes these pushrods are heavy wall but not there to get chewed by the retainer spring. I see from the pic the heads they have had the heavy duty rocker studs fitted...that's a bonus,the ''copper nuts" mentioned aren't made of copper,just plated steel nuts. |
Jake Raby |
Jul 4 2020, 06:26 PM
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#12
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
That valve adjuster was made of Chinadium......
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nditiz1 |
Jul 4 2020, 08:36 PM
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#13
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Senior Member Group: Members Posts: 1,165 Joined: 26-May 15 From: Mount Airy, Maryland Member No.: 18,763 Region Association: MidAtlantic Region |
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