Date: Sat, 27 Oct 2018 18:20:13 -0700
Reply-To: Neil N <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Neil N <musomuso@GMAIL.COM>
Subject: Re: The value of instrumentation
In-Reply-To: <BN6PR2001MB1042130B934F091949973092A0F20@BN6PR2001MB1042.namprd20.prod.outlook.com>
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Thanks Dennis.
I used a good quality carpenters straight edge and feeler gauges to
check for warpage and found nothing. The machine shop confirmed same.
Yes for sure, the head was disassembled while shop checked it. Tech
showed me that there was a little play between valves and guides but
felt that only replacing the seals was ok. In hindsight i should've
gotten new guides and possibly valve work done at that time. Ain't
hindsight grand?
Interesting point regarding warpage and cam bearing journals. I can
see that for sure.
Initially I had thought the Fram "Extra Guard" or whatever oil filter
had a bum check valve so swapped in a Mann. No change. The only real
positive change was after I reduced oil pump gear axial play. After
that, engine cold first start, oil pressure appeared instantly.
When the oil pressure issue happens i can hear a subtle noise at the
head. As soon as pressure appears, the noise abates.
This engine has been run literally not even 30 minutes. At times i
wonder if there's still assembly lube floating around in the oil
system but not sure if it is and how that might affect oiling. (cause
oil light to stay on after engine not used for 4 or 5 days).
Hopefully I'm not dealing with a valve train issue. This is an
interference engine.
Neil.
On 10/27/18, Dennis Haynes <d23haynes57@hotmail.com> wrote:
> To check for valve guide wear the head had to be disassembled. As for
> checking for warpage, on these heads warpage means garbage. It is not just
> the sealing surface. If the head is warped than the cam bearing journals are
> also out of line. So the correct fix is to twist the head back in shape, cut
> the bearing caps and bases and align bore it. Milling these heads can also
> effect the camshaft timing. Anything more than a light cut to clean the
> surface of gasket stuff and scratches has to be done carefully. A common
> head gasket failure is between the cylinder bores and I have seen where this
> breach also damaged the block.
>
> Anyway, for the engine or head "oiling system" there is absolutely nothing
> that maintains any residual oil pressure after shut down. The check in the
> oil filter only helps to keep gravity from draining everything above. Yes,
> that helps to give much faster oil flow-pressure after start up. But think
> about this, at oil change time the lifter do not go noisy for long after
> start up with an empty filter and all the passages above it. Noisey lifters
> that take a long time to fill have a problem. The problem can also be a
> valve hanging up in the guide and staying slightly open until the engine
> warms up enough for the guide to expand releasing the valve. This often
> happens after an overheating event but I have also seen it on higher lile
> engine due to glazing or carbon build up on the valve stems. I've taken out
> enough bent push rods to know that valves go get stuck.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Neil N
> Sent: Saturday, October 27, 2018 5:34 PM
--
Neil n
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