VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => IDI Engine => Topic started by: 8v-of-fury on March 02, 2009, 07:52:09 pm
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Ok so this past weekend I met up with Tyler (Burn) and he gave me an AAZ head. It's got some minor pitting and gunk built up around the valves, which to me doesn't even seem that big a deal. I will post up a few pics of everything to see what you guys think..
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092133.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092133a.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092133b.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092133c.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092133d.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092135a.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092134a.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092134b.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092134c.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0302092134.jpg)
I think if i were to clean it up a bit, and in the end run a metal HG with some studs... I wouldn't have to get it machined.. lol Which is what im aiming for here.. :P Cheap as physically possible..
So after cleaning it, even if it is a little rough, it will still be a step or two above the stock 1.6 head. Hopefully this plus the Superpump I wish to get in the near future, will really wake the N/a up :)
What do you all think? any good words of advice how to clean it up? and so on? Everything is welcome!
Jeremy
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hmm maybe scotchbrite on the sealing surfaces, and then use a dremel to port & polish 8)
the 1.9 MLS won't mean a perfect seal if its warped though...
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hmm maybe scotchbrite on the sealing surfaces, and then use a dremel to port & polish 8)
the 1.9 MLS won't mean a perfect seal if its warped though...
This is true. I don't think it is warped.. :P I will have it tested for it's trueness I suppose :P and then if it does need it, see what it will cost.. :)
Port and polish baby! WOOT WOOT lol thanks Jon
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I was just curious, does anybody know about welding the cracks between the valves. Is that the correct solution? Before a person was going to take it to the machine shop?
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If the cracks are really huge, then they should be welded shut.
If the cracks are small, just let them be.
No matter how well you weld them up, they will always crack again within minutes. That's just how VW IDI heads are, they will always, but always, have cracks between the valves.
Luckily the cracks need to be big indeed before they have any real effect on how the engine runs.
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Progress! It cleaned up fairly well! Or so I think, I've never done this before lol.
(http://i299.photobucket.com/albums/mm307/J_holubek/0303091554.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0303091526b.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0303091526a.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0303091525a.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0303091525b.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0303091525c.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0303091526.jpg)
(http://i299.photobucket.com/albums/mm307/J_holubek/0303091525.jpg)
As you can see the pitting is only on the first two cylinders, and the second two are in good shape. I was told as long as the pitting is not where the gasket needs to seal, it should be somewhat ok? lol Also the cracks between the two with the pitting are somewhat larger, but don't seem to be that bad... what do you think?
I'm not done cleanin it up yet, just wanted to get the main parts done to get some pics up. :P Tell me what you think!!
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i think those cracks look pretty bad i wouldn't personally use that head, i know you wanna be cheap, but if you were given that head u could always buy a new one off ebay and swap the valve train over, yeah thats 300 dollars but that head looks like hell and a new one will surely bring less headaches. i don't think the pitting would keep it from running fine but the cracks could i definitely get that head pressure tested if i had planned to use it. honestly i've never seen cracks as bad as cylinders one and two. looks like someone needed new injectors or had a ***ty pump tho.
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i think those cracks look pretty bad i wouldn't personally use that head, i know you wanna be cheap, but if you were given that head u could always buy a new one off eBay and swap the valve train over, yeah that's 300 dollars but that head looks like hell and a new one will surely bring less headaches. i don't think the pitting would keep it from running fine but the cracks could i definitely get that head pressure tested if i had planned to use it. honestly I've never seen cracks as bad as cylinders one and two. looks like someone needed new injectors or had a ***ty pump tho.
I don't want to be cheap, I want to be inexpensive. :lol:
I don't plan on running boost or anywhere near high horsepower. Pressure Testing, what is this? How is it accomplished? If it checks out from being pressure tested will it be okay? The cracks are nowhere near as bad as the pictures make them.. The are no bigger then 3&4. They don't even extend in to the valves at all, it just looks bad because the area has been eroded. Is the pitting tell-tale damage of bad injectors and bad pumps?
X2 on having it pressure tested. Also tip it up so the ports are facing up and pour some form of solvent in the ports. WD-40 would work even. Then check to see if it leaks out onto the combustion faces. I'm most curious whether or not the exhaust valves on the first two cylinders are leaking. I have a theory bounding around in my head that leaking exhaust valves on a boosted engine can cause engine melting temps without registering high EGTs on a gauge and could cause that type of erosion without any damage to the other two cylinders.
Andrew
It leaked out of 2 of the 8 ports. 2 that are slightly open. One of the badly worn cylinders is open.. but the other three of those cylinders didn't leak. So you think that maybe the two badly worn cylinders exhaust ports leaked causing the heat to stay in the combustion chamber longer than desired on every stroke? causing premature failure? H mm sounds intriguing :)
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I wouldn't even consider putting an old head on an engine withot pressure testing it, making sure it's flat and at least hand lapping the valves and putting new valve seals on it assuming the guides are good also. VW heads are usualy not on an engine for a reason so don't put yourself through a lot of agravation by not getting it checked and by all means do use the studs like you said.
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I wouldn't even consider putting an old head on an engine without pressure testing it, making sure it's flat and at least hand lapping the valves and putting new valve seals on it assuming the guides are good also. VW heads are usually not on an engine for a reason so don't put yourself through a lot of aggravation by not getting it checked and by all means do use the studs like you said.
hand lapping the valves, how is this accomplished? If this gets done, and it is pressure tested, checked for its flatness and new valve seals. It should be good to go.. right?
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Send it to the diesel head magic man: Franko6. That guy needs to be a registered vendor over here. His head work is Mag-fn-nificant!
Either way, rebuild or buy new, it's gonna cost you some coin to do it right. Your time is free, but nothing sucks more then dumping hours and hours plus an ample amount of knuckle skin into a rebuild just to have something that was marginal fail and take something else out in the process.
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I askde Franko6 to join about a year ago. He said no one wants IDI heads... :roll:
You can check the flatness yourself fairly easily to save some coins
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Hand lapping is accomplished by placing a small amount of valve grinding compound between the valve and seat and using a suction cup tool to rotate the valve in the compound. It basically works similar to sandpaper and helps the valves to seal completely.
Andrew
Its implied that you remove the cam, lifters, and springs prior to lapping. And, yes, lapping is a very very good idea. I would also be a little concerned about the erosion next to the precombustion cup on that first cylinder - looks like it might affect it, maybe not.
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I would also be a little concerned about the erosion next to the precombustion cup on that first cylinder - looks like it might affect it, maybe not.
What are your views on this, what do you think it will cause to happen? Not askin to be a smart ass, just because i simply don't know :)
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it might cause it to be loosened and fall out.
if you do use the head I would aggressively peen around the prechambers to keep that from happening.
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The obvious wear around 3 and 4 seats is troubling. The ugliness near the pre-chambers is a whole different story.
I'd guess you could get a head in nicer shape for the half the money you'd have in trying to fix that. Even Frank would charge you in the 700 dollar range (based on his TDI head work, which is easier to do) to tear down, weld, cut, reseat, resurface, and do a complete valve job on a head like that IF it's not beyond repair.
And in my opinion, the reason nobody wants frank to fix IDI heads is because they don't want to pay what he would ask to do it.
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it might cause it to be loosened and fall out.
That would also be my primary concern, someone got that head VERY hot with stuck open / leaky injectors in 3 and 4
You'd have to remove the PC, weld, recut , clean, glue and peen the PC's back in to be sure they didnt come loose. :(
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doh, sorry I obviously haven't had enough caffeine today
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what do the insides of the pre cups look like? probably look like *** considering how the heads surface looks
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what do the insides of the pre cups look like? probably look like *** considering how the heads surface looks
There nice and smooth like the surface of the pre-cups.
Check for flatness. peen the cups in, pressure test it. Good to go. You gotta understand something here, I'm not going to run a turbo, and I'm not gonna be pumping a crazy amount of fuel in either.. I just want this head because it breathes so much better then the stock 1.6 head :P I want economy not performance
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Hand lapping is accomplished by placing a small amount of valve grinding compound between the valve and seat and using a suction cup tool to rotate the valve in the compound. It basically works similar to sandpaper and helps the valves to seal completely.
Andrew
Its implied that you remove the cam, lifters, and springs prior to lapping. And, yes, lapping is a very very good idea. I would also be a little concerned about the erosion next to the precombustion cup on that first cylinder - looks like it might affect it, maybe not.
Yes you have to tear it completely down but you have to do that anyway if you want to put new seals on it, I know I would. If you don't have the tools and aren't sure about it just have the machine shop do it when it's pressure checked, seals aren't that expensive to put on while the head is off. Just don't put a questionable head on and then start suspecting other things that are wrong when you aren't sure about the head first.
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Just don't put a questionable head on and then start suspecting other things that are wrong when you aren't sure about the head first.
Hey man, this is my first diesel. Its all learning experience the first time around, PITA second time around right? lol So if this head will make the engine run marginally better then I would love to have experience swapping a head! Gotta learn somewhere right? I understand though, the head will never be perfect with the amount of wear it has. If it checks out in every way and i get new seals, and peen the pre-cups in.. It should be fine. When your 19, you do things for the hell of it, something to do. A learning experience like I said. Now if i were 42, full time job, had a wife and three kids and diner to cook... than I wouldn't be doing this for the hell of it. Also if my car goes out of commission for a while, no biggy, i don't rely on it. This won't be for a while anyway.. I want to swap in the N/a in stock form before i do any mods so i can really enjoy them as Tyler says :P
Thnaks for all your guys help! :P Oh, I think you should know, my ENTIRE car is a learning experience :lol:
Jeremy