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Engine Specific Info and Questions => IDI Engine => Topic started by: addautomotive on May 26, 2005, 06:31:58 am
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Hey folks, I just did some horse trading and scored a '94 1.9 TD engine. It's kind of a sad tale... the guy had the standard 1.9 crank pulley issue, lost the timing and had the head rebuilt. To save $$, he decided to reassemble everthing himself. He cheaped out, and used silicone instead of valvecover & oil pan gaskets. Before he even got it out of the driveway the engine sucked up a blob of silicone, plugging an oil passageway. 2 cylinders are badly scored and from what I'm told the 2 pistons are probably shot too. I haven't even seen the engine... I'm getting it on Sunday. I traded a 1.6 NA and a complete front suspension for it.
I'm pretty happy with the swap. I figure it shouldn't be too hard to get my mitts on a lower end, as most of the 'junked" 1.9s are crapped out with bad heads.
Anyhoo, any ideas on how I should proceed? Get a new(used) bottom end? Have the offending cylinders sleeved? How much oversized can I go without getting oversized pistons? Or, Is it possible to bore the block and fit larger pistons? Or should I just sell all my car junk and lease a new Cavalier with an automatic transmission?
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cavalier!! quality engineering. :o
pistons can be bored over depending on how bad the damage is and if they've been bored over already.
you in the states? might be hard to find a block down there but in canada should be easier. see what a good used block would run you. probably cheaper than shop time for overbore and new pistons.
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I'm in New Brunswick, and make regular trips to Montreal, so finding a block wouldn't be a problem.
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Bore 'em and oversize pistons. The block material is hearty. When I was in college (read no money) and working at a VW/Porsche shop, I built a motor for my Rabbit Truck from free used parts. Yes, free.
The bloc kwas from an Audi 4000 1.8 that had lost a headgasket on one cylinder - so there was a visible and very feelable gouge, about 1/4" wide most of the bore. Cleaned all the parts, used pistons from a Fox, noew rings, honed, etc etc, and ported and rebuilt the head from the Audi.
Even with a Weber 2 barrel carb I could beat up on Stockish GTI Rabbits.
Point is, if you over bore & remove the gouges/scores (which I didn't) it will be good as new.
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Anyone know how much I can bore before getting oversized pistons?
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None. You can hone a very slight amount, but you can't bore to make the hole bigger without a bigger slug to fit the hole.
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Well, after much waiting I finally have this engine in my garage. but sure enough the #2 & #3 cylinders are badly scored, and the pistons are in bad shape too.Luckily, the recently rebuilt head looks great.
The gauges are far too deep to get away with honing... looks like I'll need to either rebore or get a new bottom end. Anyone know a good source of oversized pistons? Or good bottom ends?
Another question... the guy who I got the engine from thought the crank may have been replaced with a TDI crank, instead of simply having teh keyway machined. How can I tell for sure?
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Another question... the guy who I got the engine from thought the crank may have been replaced with a TDI crank, instead of simply having teh keyway machined. How can I tell for sure?
The TDI crank will have a machined area, 3 tapped holes and a dowel pin on the rearmost bobweight that were used to mount the crank position sensor wheel. If the previous "mechanic" was really lazy the crank position sensor wheel may actually still be bolted on. The AAZ has no crank sensor wheel and the crank is not machined to accept one.
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Where do I find the engine code? I looked around but couldn't see it anywhere.
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The engine code is located on the front of the block, just above the oil filter bracket. The number is stamped into the same machined area that the oil filter bracket mounts on. The numbers can be difficult to see, you may need to wire brush the area. The engine number will begin with "AAZ" followed by a 6 digit code.
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man, quick td, is there anything you DONT know about these engines?
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hmmm... had a closer look today. There is an indentation & small crack between the intake & exhaust valves for each cylinder. Is that common?
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Yes.. that is nothing to worry about, the closest oil of coolant is more than a cm away.
All IDI heads have the same cracks.
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SWEET. So then I will probably just have to find a new bottom end, or some oversized pistons.
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I dare you to pull that head. I'll wager a case of your favorite brew that it's cracked now. Fix 'em all you want, they'll be back.... :D
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ok.. but thats a new/refurbished head... ;) Or did you do something special with the crack area?
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So, I've got this engine torn down, the #2 & 3 pistons are beat up pretty bad. Those cylinders are pretty rough too. If I get my mitts on some used pistons, can I bore 30 over and use 30 over rings?