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Engine Specific Info and Questions => IDI Engine => Topic started by: Caddy-Daddy on August 12, 2004, 09:45:42 am
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Hi Guys.. will this fit? I think it will. Are these heads the same or are there differences.. extra coolant passages etc..???
And I mean the hydro heads.. Just wondering what the differences are and if there are any.. as N/A heads are easier to find over here..
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there are differences... oil squirters etc but i'm no expert.
yes, it should bolt up.
a TD head is definitely prefered.
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You mean these squirters under the piston?
(http://www.vwcaddyforum.nl/plaatjes/turbo/pistoncooling.jpg)
Yeah I know about that..
Just wanna know why a TD head is preferrable... I also know it bolts on.. I have compared headgaskets of both and could not find anything different aswell...
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if you're only changing the head the oil squirters shouldn't be an issue, but i know for sure that there are some differences between NA and TD heads.. just don't know offhand what they are.
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The part number for replacement head castings (that is, assembled with valve seats) of a 12mm head-bolt 1.6 NA head is the same as a 1.6lTD head.
If you look at the heads that actually came off 1.6lTDs and 12mm 1.6lNAs, the casting numbers actually cast into the heads (which don't correlate to any part number it ETKA :? ) are different. So, there is a possibility I suppose the metal content is different. Although there is also strong evidence (replacement part numbers being same in ETKA) that VW already incoporated the changes for turbo into the 12mm-head bolt 1.6lNA heads.
If you get a 1.6lNA head intending to put it on a 1.6lTD and have a chance to rebuild it, I'd recommend replacing the valves with turbo parts during the rebuild. Specifically, I think it's just the intake valves that ETKA lists are different vs the NA vs Turbo 1.6l heads.
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Thnx for the info Guys...
Wonder what the difference would be than with the intake valves.. Natrium filled valves?
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Thnx for the info Guys...
Wonder what the difference would be than with the intake valves.. Natrium filled valves?
None of the VW Diesel valves that I am aware of are sodium (element "Na") filled. The 1.6l naturally aspirated diesel intake valve is part number 068 109 601 D, while the 1.6lTD intake valve is 068 109 601 C. Maybe buy one of each, take a close look and let us know!
Exhaust valve has part number 068 109 601 D for both the solid lifter 1.6lNA and 1.6lTD motors.
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hey,
im running a N/A head on my TD and have had no problems with it.
isnt the whole head made differently? i cant think right now of whats different but im sure there is a major difference between the two, but it seems to work fine.
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The only visual difference I have ever found is the little mark on the prechamber. The TD prechambers have a triangle shaped mark and the NA prechambers have a round dimple. Other than that one cannot tell the difference by looking.
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I have read reputable industry sources that say material and heat-treatment of the heads are different between NA and TD.
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As I've said before, there is no dispute that when the TD was first engineered back in the early 80's, vs the early, 11mm head bolt, 1.6l NA motor of the time, there were indeed many differences NA to TD. These are well documented in multiple reliable sources, however the best, most thorough, and most original source is VWoA's "Introductory Service Training Information, 1982 Quantum Turbo-Diesel" Pamphlet. This seems to be the only source of information that was used for the TD-specific pages in the Bentley manual. Another good source is the 1.6lTD SAE Paper but it's not as complete as the Introductory Service Training pamphlet.
However, it is also clear that at least some of these changes were carried over to 1.6lNA production in the mid-'81 model year. With this update of the 1.6lNA motor, it's crankshaft changed to the TD-style snout, and it's head bolts were upgraded to the TD-spec 12mm versions. It is not conclusive but it wouldn't surprise me if other TD-spec changes were migrated over at that time, for example changes to valve materials, head casting materials, etc. And in fact information from ETKA on replacement parts seems to imply this.
There isn't a complete list of differences from a reputable source, comparing a late model solid lifter, say '83 or '84 1.6lNA motor to a solid lifter 1.6lTD.
To assume that all these changes between NA and TD exist in the '83 and '84 1.6lNA vs TD motors exist simply isn't true, as it it taking the only 2 original sources of information regarding changes between 1.6lNA and 1.6lTD: the 1.6lTD SAE Paper, and the 1982 Quantum Turbo Diesel Introductory Service Training Information manual out of context. The Normally aspurated engines being compared in both of those sources are early, pre-TD development motors. Not the later, 12mm-head bolt, updated crankshaft iterations that is more common to us now.
Although I can't rule out the possibility that ETKA changed part numbers over time, it's also pretty hard to refute when ETKA says 1.6lNA and 1.6lTD gets the same part number, that it's not true.
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jake... sometimes a part becomes NLA ...and instead of making it NLA, EKTA is changed to specify another part that is still actually available. doesn't mean it was original equipment... just the only part available that will fit.
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Still not conclusive either way.
The only official data on changes between NA and TD I've ever seen are comparing the 12mm head-bolt TD to the 11-mm head bolt NA. If you have anything else, I'd be interested in seeing it.
It is also undisputed that VW put the 12mm head bolt head, which was an upgrade specifically designed for TD application, into their NAs in the '81 production model year. It is also undisputed that VW also updated the crankshaft to the style of snout design for TD application (harmonic balancer compatible) also at this same time. These changes can be readily observed by disassembling original VW engines and observing the parts.
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jake 99
me 1
you're the man jake... just pointing out something about EKTA i picked up working at the dealership.
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I recently read somewhere that the types of metal are different and that the valve seats are harder. Then again, I know people who have put significant mileage on N/A motors with turbos bolted on. Not even a TD pump!!
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ifound na and turbo prechambers different sizes,,turbo is bigger chamber,,i think somewhere it mentions something like na is 30mm turbo is 32mm,and thats the part you see when its in the head,,i did a comparo side by side,they are different,,, once tried cutting a exhaust valve from a td,and it didnt bubble in water,not sodium filled like theysay,,,,,ive ran na's as turbo setups,,gotten a few years out of them too,depends on how much fuel you put to it,,,,and i cant find new "turbo" prechambers either,,i thought someone modded some gm 6.5 prechambers or something,,anyone know a source for new prechambers?
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Do you remember which types of heads you measured, as I don't believe that solid lifter heads have the same prechambers as hydraulic lifter heads. (Mark Malone has documented different size prechambers comparing a 1.6lNA solid lifter head versus a 1.6lTD hydraulic lifter head here: http://www.vwdiesel.net/phpBB/viewtopic.php?t=2329&start=35 )
I just remember that I have a 1.6lTD solid lifter head in my garage off the engine, and was going to measure the OD of one of the prechamber faces. I'll do that and will report back here.
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how do you get the prechambers out?
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The Diesel Head shop that did my TD Head installed Cast Iron Valve Guides. Work better for the heat.
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how do you get the prechambers out?
Stick a stout wooden dowel in where the injector goes and hammer them out.
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I measured the prechamber face diameter on the 1.6lTD solid lifter head today, and it matched the 32mm of the 1.6lNA solid lifter prechamber reported by Mark Malone.