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914World.com _ 914World Garage _ Valve adjuster squashed
Posted by: nditiz1 Jun 29 2020, 02:45 PM
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.
Posted by: BillC Jun 29 2020, 03:05 PM
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.
Posted by: porschetub Jun 29 2020, 03:26 PM
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.
Posted by: nditiz1 Jun 29 2020, 04:00 PM
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.
Posted by: brant Jun 29 2020, 04:13 PM
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
Posted by: burton73 Jun 29 2020, 04:53 PM
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
Posted by: nditiz1 Jun 29 2020, 05:36 PM
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
Posted by: porschetub Jun 29 2020, 05:46 PM
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.
Posted by: porschetub Jun 29 2020, 05:55 PM
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.
Posted by: RoadGlue Jun 29 2020, 08:07 PM
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.
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.
Posted by: porschetub Jun 30 2020, 01:17 AM
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.
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.
Posted by: Jake Raby Jul 4 2020, 06:26 PM
That valve adjuster was made of Chinadium......
Posted by: nditiz1 Jul 4 2020, 08:36 PM
That valve adjuster was made of Chinadium......
It was just replaced by a Germandium one. Should hold up much better.
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