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Questions on 1.6 TD
by
96_yota
on 06 Sep, 2015 21:16
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New here and to the VW 1.6, i'm swapping a 1.6 td engine code CY into a 1980 Toyota pickup. I picked up the engine from a guy off of craigslist (miles unknown) after searching for months, only thing missing is the intake manifold so ill need to find one of those. Im going to go ahead and rebuild the engine before we drop it into my truck. I pulled the engine apart and pulled the head off of it to find on the top of three of the pistons markings that say 76.98mm along with a few other numbers, Ive read that stock bore on the 1.6 is 96.5mm so has this engine been over bored in the past? When I pulled the head it was pretty clean on the inside can still see some of the cross hatching in the cylinders but there is a rust ring in at least two of the cylinders, im hoping this can be honed out. I pulled the rod caps and there was minor wear on the bearings crank could probably be polished and run again.
The head has very small cracks between the valves (common ive read), cam had minor wear on it (haven't removed it and checked the followers for any damage yet). My plan is to get the head to a machine shop and get it checked out replace and guides/seals/springs/valves if needed and possibly port the head while its off. Plans so far if the bottom end checks out and just needs bearings/hone/rings, MLS head gasket, ARP studs, ported head, new valve seals, new oil pump/water pump, gaskets throughout, maybe a turbo upgrade, we will put a intercooler on it and fab up the cold side piping.
Now my question is can anyone tell me if these are stock pistons? I don't see why someone would replace only three of the pistons but also don't see why the factory would only mark three of the pistons. Anything you guys would replace along with what ive said? Im going to make an adapter plate to use the factory Toyota 5 speed trans, going to mark TDC while the head is off.
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#1
by
96_yota
on 06 Sep, 2015 21:25
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#2
by
96_yota
on 06 Sep, 2015 22:56
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Answered my own question, looks like three of the cylinders are bored .020" over. I guess its time to strip the block and get some measurements taken on everything and start ordering parts.
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#3
by
billybobf
on 06 Sep, 2015 23:16
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Where you from? I have a Toyota adapter I am putting in my samurai
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#4
by
theman53
on 07 Sep, 2015 06:47
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I recommend not "replacing what looks bad" on these 8v heads. IMHO if there is 1 bad part you probably need to go through the entire thing. Unless you knew that you have a head with 10,000 miles and you just want to freshen it up, I would replace valves, seals, seats ground, guides. It is beneficial and less headaches later. Also, judging by 3 holes with new pistons and one not, whoever did this probably took every short cut possible, so I would replace everything on the head as a principle move.
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#5
by
libbydiesel
on 07 Sep, 2015 07:28
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Polish the pre-chamber inserts to a shine and very closely inspect for the tiny cracks emanating from the opening. If the inserts are cracked, replace them.
If there is any palpable ridge in the top of the cylinder then your bores are out of spec (piston to cyl. clearance wear limit is 0.003). It is *very* rare for the bores to be within spec for honing. You can go to the last oversize (77.48mm). If doing so, make sure the machine shop that does the boring is willing and able to do the 0.0012 piston to cyl spec for new pistons.
It's less likely that someone replaced three pistons and more likely that they had an issue with the one that is different (e.g. dropped valve, broken pre-chamber insert, or foreign debris ingested as indicated by the impressions in the piston). I don't see the matching marks in the head (although there isn't a closeup of each combustion face) so the head might have been replaced.
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#6
by
96_yota
on 07 Sep, 2015 07:56
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Where you from? I have a Toyota adapter I am putting in my samurai
I'm from Mooresville, NC
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#7
by
96_yota
on 07 Sep, 2015 07:58
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I recommend not "replacing what looks bad" on these 8v heads. IMHO if there is 1 bad part you probably need to go through the entire thing. Unless you knew that you have a head with 10,000 miles and you just want to freshen it up, I would replace valves, seals, seats ground, guides. It is beneficial and less headaches later. Also, judging by 3 holes with new pistons and one not, whoever did this probably took every short cut possible, so I would replace everything on the head as a principle move.
I shouldn't of said replace parts as needed, this is what I meant. Probably going to just go through the entire head like you said.
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#8
by
96_yota
on 07 Sep, 2015 08:09
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Polish the pre-chamber inserts to a shine and very closely inspect for the tiny cracks emanating from the opening. If the inserts are cracked, replace them.
If there is any palpable ridge in the top of the cylinder then your bores are out of spec (piston to cyl. clearance wear limit is 0.003). It is *very* rare for the bores to be within spec for honing. You can go to the last oversize (77.48mm). If doing so, make sure the machine shop that does the boring is willing and able to do the 0.0012 piston to cyl spec for new pistons.
It's less likely that someone replaced three pistons and more likely that they had an issue with the one that is different (e.g. dropped valve, broken pre-chamber insert, or foreign debris ingested as indicated by the impressions in the piston). I don't see the matching marks in the head (although there isn't a closeup of each combustion face) so the head might have been replaced.
Polish inside the prechambers or just the face? I looked over the inserts and didn't see any cracks but I'll make sure to give them a closer inspection.
There isn't really any ridge at the top of the cylinders, just some build up of diesel gunk that comes off with a rag and brake cleaner. I work at a mustang performance shop and have a engine builder I trust so I'm going to talk with him to see if he has ever messed with one of these before.
If something was dropped into the cylinders needing a rebuild it looks like another head was used after the "rebuild" as there aren't any matching marks in the head. I just don't understand why only replace 3 pistons.
Anone have any leads on good machine shops that are known for this kind of work in the Charlotte NC area just incase my guy doesn't want to take on the build?
Edit: I couldn't figure out how to multi quote on my phone
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#9
by
libbydiesel
on 07 Sep, 2015 09:01
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The cracks on the inserts will be on the face, typically radiating from the thinner lip of the opening. You often will not be able to see them until ALL carbon/buildup has been removed and the insert shines.
As I said, I doubt that three pistons were replaced, but rather one was replaced as the one that was replaced was more significantly damaged than the other three.
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#10
by
Dakotakid
on 07 Sep, 2015 11:40
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If you have not removed the pistons and rods yet, I would clean the tops of the existing pistons (very clean) and measure piston protrusion PRIOR to disassembly. Why? Because I would be trying to see if those rods appear to be matched on length.
Are you simply sure that the previous owner did not sand the top of one piston in an effort to remove craters?
I'm a bit confused as I thought all "CY" code engines were solid lifter engines......whatever. Hmmm...............
You are going to have to look around to find 4th oversize pistons. "Quality....(whatever name he uses)" in Montclair, Calif. may still have KS large pistons. If you can find an additional full set of rings to fit those big pistons (even though his KS would come with them), I would buy them now (for later ring wear). And, I say that because finding 4th-over rings (when you need them) is NOT an easy task.
If fitting a hydro head, you need new lifters as well. Hey.....hydro head rebuilding is NOT cheap (as you are soon to see).
Also, inspect the hydro cam for lobe flaking PRIOR to rebuilding. Many hydro cams had very poor hardened surfacing and they literally fall apart. Don't rebuild that hydro head until you can locate a good camshaft (if it needs it). Those cams are getting hard to locate.
I prefer to avoid the hydro head problems and expenses and run solid heads on hydro blocks......whatever.
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#11
by
96_yota
on 07 Sep, 2015 13:40
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If you have not removed the pistons and rods yet, I would clean the tops of the existing pistons (very clean) and measure piston protrusion PRIOR to disassembly. Why? Because I would be trying to see if those rods appear to be matched on length.
Are you simply sure that the previous owner did not sand the top of one piston in an effort to remove craters?
I'm a bit confused as I thought all "CY" code engines were solid lifter engines......whatever. Hmmm...............
You are going to have to look around to find 4th oversize pistons. "Quality....(whatever name he uses)" in Montclair, Calif. may still have KS large pistons. If you can find an additional full set of rings to fit those big pistons (even though his KS would come with them), I would buy them now (for later ring wear). And, I say that because finding 4th-over rings (when you need them) is NOT an easy task.
If fitting a hydro head, you need new lifters as well. Hey.....hydro head rebuilding is NOT cheap (as you are soon to see).
Also, inspect the hydro cam for lobe flaking PRIOR to rebuilding. Many hydro cams had very poor hardened surfacing and they literally fall apart. Don't rebuild that hydro head until you can locate a good camshaft (if it needs it). Those cams are getting hard to locate.
I prefer to avoid the hydro head problems and expenses and run solid heads on hydro blocks......whatever.
I haven't taken the short block apart just yet, so I'll measure protrusion first. The only reason I don't think all four pistons were replaced is because three (1,2, and 4) all have the same numbers on the 76.98mm and a few other numbers stamped into the tops where piston number 3 is completely flat with no numbers in it.
Sorry for the confusion the head I have is a solid lifter head.
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#12
by
Dakotakid
on 07 Sep, 2015 13:44
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Oh, is that head an AMC or China head?
It's got the 2nd oil return hole. Just wondering.
Did I miss something in the translation?
Does your engine block deck have BOTH oil return holes?
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#13
by
libbydiesel
on 07 Sep, 2015 14:20
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The only reason I don't think all four pistons were replaced is because three (1,2, and 4) all have the same numbers on the 76.98mm and a few other numbers stamped into the tops where piston number 3 is completely flat with no numbers in it.
Are you suggesting that the previous owner over-bored and replaced the pistons on only three of the four cylinders. I've never heard of such a thing. Yes, the three that are marked are oversize and so obviously not original. The one that does not have any markings is ALSO not original and I would be astounded to find that it was not the same diameter as the other three.
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#14
by
96_yota
on 07 Sep, 2015 14:22
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Oh, is that head an AMC or China head?
It's got the 2nd oil return hole. Just wondering.
Did I miss something in the translation?
Does your engine block deck have BOTH oil return holes?
The head says made in Germany on the injector side and has both drain holes. The block also has both drain holes. Looks like all the pistons stick out of the deck by a small amount.
