Author Topic: AAZ head rebuilding questions  (Read 2457 times)

July 03, 2010, 09:51:42 am

burn_your_money

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AAZ head rebuilding questions
« on: July 03, 2010, 09:51:42 am »
I'm in the process of P&Ping my head and figured I may as well check for valve guide wear. Bentley specs max play at 1.30mm. I have (in order from 1 to 8):
1.00
0.60
1.05
0.45
0.50
1.00
0.50
0.90

Should I be concerned? I will be installing a cam with more lift if that makes any difference. What is the play with new guides?
Tyler

Reply #1July 03, 2010, 10:22:46 am

Vincent Waldon

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Re: AAZ head rebuilding questions
« Reply #1 on: July 03, 2010, 10:22:46 am »
Most machinists I know think the Bentley spec is nuts...given how much even 1mm wobbles they might be right.

As usual its a judgement call...on heads I am planning to keep around for a while I usually invest the money and get em done over 0.6 mm

Vince

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Reply #2July 03, 2010, 11:09:23 am

BAM

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Re: AAZ head rebuilding questions
« Reply #2 on: July 03, 2010, 11:09:23 am »
Brand new guides and valves have almost 0 play once the guides have been sized.  The specs you listed are all within spec I personally would not worry about it.  I have seen old 1.6l NA running between 2-3mm and that was about 70000km ago.  If you were a client, I would recommend new guides and valves reseated especially if you intend build something a little more high performance than factory.  Your new cam may create issues with your guides and the wear pattern from the previous cam not sure.  I agree with Vincent if you are keeping the head for awhile and you do not like the way the guides taste and smell put new ones in they are cheap.  You will require the correct size of reemer to size them once installed in the casting. 

Reply #3July 03, 2010, 08:45:33 pm

burn_your_money

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Re: AAZ head rebuilding questions
« Reply #3 on: July 03, 2010, 08:45:33 pm »
Thanks guys. I think I'm going to leave well enough alone and hope for the best. It ran fine before I pulled the head...
Tyler

Reply #4July 03, 2010, 09:25:38 pm

Vincent Waldon

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Re: AAZ head rebuilding questions
« Reply #4 on: July 03, 2010, 09:25:38 pm »
Yup... I think you will be fine... Do new seals if you can.
Vince

Edmonton, Alberta, Canada
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Gone but not forgotten: 1969/1971 Beetles, 1969/1974 Westies, 1979 Rabbit, 1986 TD Jetta, 1992 gas Jetta, 1994 TD Jetta

Reply #5July 04, 2010, 02:28:56 am

Smokey Eddy

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Re: AAZ head rebuilding questions
« Reply #5 on: July 04, 2010, 02:28:56 am »
new seals are easy peasy :) needle nose pliers make quick work of them and a deep socket the right size works great for pressing the new ones in.
valve stem seals are cheap cheap cheap

my valves wiggle a little too. i was thinking about it but it honestly can't be that much to matter. with a film of oil on them i can't see them damaging anything
knock on wood....
watch my new AAZ drop a valve in the first 10,000km now that i've said that...
Ed
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Reply #6July 04, 2010, 06:15:39 am

burn_your_money

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Re: AAZ head rebuilding questions
« Reply #6 on: July 04, 2010, 06:15:39 am »
Yep old seals have already been pulled out.

Here's a question, let's say I already lapped my valves and then decide to throw in new guides. Will I need to re-lap them?
Tyler

Reply #7July 04, 2010, 10:48:30 am

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Re: AAZ head rebuilding questions
« Reply #7 on: July 04, 2010, 10:48:30 am »
At least re-lap after new guides.  Should really check and make sure valve & seat are sealing correctly.  If you do not check and there is a problem it will show when you lap then in.  95% of the time a quick re-lap and it is all good.   :) :)