this can't be possible

[projectgotsi]

ok, this does not seem possible to me. I have a 93 tsi 5sp with a 90 engine, timing belt went so I bought a remanned head from National Cylinder Head. Bolted the head on and the car has not ran right sence. After spending a ton of time under the hood and even taking it to the dealer....i took it to a "specialist" with interfearence engines. They checked all the work and told me that I am 1/2 "tooth" off on my timing at the crank. He also said that thier was no way to line it up correct, everything is lined up and correct, but the crank will be 1/2 tooth off either way. They are trying to tell me that the head I got may have been "over milled" and is now too short and is throwing the timing off. I cant belive it. I called Natl. cylinder head and they told me that they have sold over 1 million heads and have never had this problem and all the heads are machined under factory specs. Are we missing somehing? Please help! Andy

 

[projectgotsi]

oh yeah, when I took the orignal head off...we took it to the shop to get a price on getting it rebuilt, they lost my cam gears and gave me new ones, could they be the wrong size...?

 

[cootees]

They could, it's always a possibility. If I were you I would get some good adjustable cam gears. That should fix your problem.

 

[BUCK]

My bet is incorrect Timing Belt Tensioner setting - I don't know how else you could get 1/2 a tooth off... As far as the part about the over machined Head - if you did that you'd have pistons bending valves - which WOULD cause it to run poorly... Another set of stock Cam gears should work IMO. I take it National has the right cams in the right saddle in the right Head - every MILLION or so they COULD make a mistake...

Here's my favorite recent Thread on this...

http://www.dsmtuners.com/forums/showthread.php?s=&threadid=87171

 

[DSM007]

I remember when I did my timing belt two years age my exhaust cam would like "go out of time" when the belt was ran around everything and the tentioner was installed tightening everything up......so in effect I had to redo the timing belt over again but the second time I had to move the exhaust cam gear off one tooth so when the tentioner tightened everything back up the cam gears would line back up poperly.....anyone ran into this before and maybe better expain this for our guy having problems?Cause I thing this is his problem with his car.

 

[projectgotsi]

thanks, well I did re-use the belt and tensioner (they only had about 2k miles on them) I dont see how that could affect the crank, if everything else lines up perfect, and the crank is off 1/2 tooth, I dont see how that could be belt tension

 

[BUCK]

by projectgotsi thanks, well I did re-use the belt and tensioner (they only had about 2k miles on them) I dont see how that could affect the crank, if everything else lines up perfect, and the crank is off 1/2 tooth, I dont see how that could be belt tension

Yes it certainly should be fine with only 2K on it provided it's not oil soaked or damaged - BUT - the VERY post before yours talks about how to explain your phenomena - so please READ the thread I attached & LISTEN to guys like DSM007 who are trying to help - your "experts" suck - they don't care - fact is until YOU become an expert on this area this car won't be fixed - NO ONE cares except you & a few guys on these boards.

by DSM007 : when I did my timing belt two years age my exhaust cam would like "go out of time" when the belt was ran around everything and the tentioner was installed tightening everything up......so in effect I had to redo the timing belt over again but the second time I had to move the exhaust cam gear off one tooth so when the tentioner tightened everything back up the cam gears would line back up poperly.....

You have a choice when you lay the belt up initially on the sprockets with no tension - either bias the Exhaust Cam one tooth off - OR - line the Cams & Crank & Oil Pump up perfectly & watch the Exhaust Cam & the Crank roll out of time AS YOU TENSION IT - The "SLACK AREA" of the belt is that forward run where the tensioner is (by design of course) - You can watch the Intake cam & the Oil pump sprocket sit there static while the Tensioner rolls the Exhaust Cam & the CRANK (crank being the easiest to turn of all the sprockets with no spark plugs in) - The tensioner TENSIONS the slack area AND the area at the top between the 2 Cam sprockets which allows for movement that puts it OUT OF TIME.

- UNLESS you biased the initial Belt settings.

THEREFORE - If one were to bias the initial placement of the belt but UNDERTENSION the belt it would NOT FALL BACK INTO TIME via the Tensioning process... (like yours)

OR - you could NOT bias the initial laying on of the belt - UNDERTENSION the Belt & pull the timing marks off just a very little... (like yours).

Use the grenade pin to set Tension.

It's possible that even Overtensioning can get you your scenario but I'm not so sure - you can add to our knowledge regarding that.

Hopefully you can "see that" Projectgotsi.