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Engine Specific Info and Questions => IDI Engine => Topic started by: paolomarks on March 24, 2011, 06:23:43 am

Title: aaz valves and srings
Post by: paolomarks on March 24, 2011, 06:23:43 am

Hello, I've got an AAZ out of a 96 golf(Canada)  is it true that the AAZ only had outer valve springs? Mine have no inners.  If needed can I replace them with inners from a 1.6 NA  mechanical head?  Thanks in advance, Paolo.

Title: Re: aaz valves and srings
Post by: Thezorn on March 24, 2011, 11:08:20 am

Mines a 93 AAZ and it has 2 valve springs per valve.

Title: Re: aaz valves and srings
Post by: Mark(The Miser)UK on March 24, 2011, 03:22:35 pm

2 springs and identical to the 1.6td ones & n/a ;D

Title: Re: aaz valves and srings
Post by: paolomarks on March 25, 2011, 09:01:45 pm

thanks, for the replies.  Wonder why the PO removed the inner springs?  Any advantage to doing so?  Paolo

Title: Re: aaz valves and srings
Post by: Vincent Waldon on March 25, 2011, 09:42:24 pm

Both my AAZ heads only have single springs.

Title: Re: aaz valves and srings
Post by: rabbitman on March 25, 2011, 09:53:37 pm

Don't some AAZs have 7mm valves and some 8mm? If that's right maybe the lighter 7mm ones don't need as much spring strength to return it.

Title: Re: aaz valves and srings
Post by: rallydiesel on March 25, 2011, 10:03:36 pm

I have a head with 8mm stems and single springs.

Title: Re: aaz valves and srings
Post by: Mark(The Miser)UK on March 26, 2011, 08:14:19 am

Reading up; AAZ had inner and outer springs, up to 1997ish, then had only one spring, whilst the 1Z and AHU began/carried on the dual spring setup. Code was 028 109 623 A, outer, and 028 109 633A inner, later the single spring was 028 109 623B
Interestingly it seems the AAZ continued to be issued with the dual spring 'carrier'
Finally ABA,and AAC came along with the 028 109 623 'C' outer, no inner

Title: Re: aaz valves and srings
Post by: paolomarks on March 26, 2011, 06:22:36 pm

Hey, you guys with the newer AAZ's with only one spring, I'm wondering if your springs have the lower "Carrier" to center and support the spring, like the 1.6's have. My '96 just has the top "carrier", which by the way is the exact same part as the 2 spring models. Why did VW switch to the one spring.?  Don't 2 dissimiler springs reduce vibration because their differing vibrational frequencies tend to cancel out unwanted vibration?.  What do you guys think.?  Paolo

Title: Re: aaz valves and srings
Post by: rallydiesel on March 26, 2011, 06:46:01 pm

Mine has a top and bottom spring plate. Wouldn't the spring wear into the aluminum head if there was no lower plate?

Title: Re: aaz valves and srings
Post by: paolomarks on March 27, 2011, 07:37:56 am

Has anyone ever seen a single spring set up without a lower "carrier"?  This is how I found mine, but I have no idea what the PO did.  Thanks, Paolo

Title: Re: aaz valves and srings
Post by: Vincent Waldon on March 27, 2011, 10:26:14 am

Yup... that's how my single-spring heads are.

Title: Re: aaz valves and srings
Post by: paolomarks on March 27, 2011, 04:45:24 pm

Great!, Thanks for the help.  Question still remains, though , why would VW switch from  a 2 spring set up to the single.?  Cheaper?  Less reciprocating mass?.