Duncan Posted August 2, 2020 Report Share Posted August 2, 2020 (edited) I've been scratching my head on this one. Short back story: Didn't properly block my chain tensioner when I pulled the head of my L20b. I *did* mark the chain and cam gear gear when I removed it. Sent head to machine shop for valve job and they requested I leave the gear on it. I asked them (very implicitly) NOT to hot tank the gear due to the mark to line up the chain. Of course they hot tanked the gear and my mark was gone. I didn't think I needed to take a photo, so I didn't know what number to use to put it back on. So now, the whole thing is apart and I have new guides, tensioner, and a new chain is on it way. I should also mention the old chain has ZERO markings or brite links on it. After reading for hours and watching videos, I have a fairly good idea the new chain needs to go on number 2 being an L20 and all. Here's the problem.. At TDC, it's my understanding this dimple should be around 3-4 o'clock-ish and not at it's current position. I absolutely have it on TDC and the pulley is lined up to the pointer on the front cover, and in addition, number 1 and 4 pistons are up. The front pulley is keyed to only go on one way, so it really can't be off by 180 degrees..Is it possible to get that bottom gear on the motor wrong? Based on previous work done to this wagon, nothing surprises me anymore. This car even had iron-on denim patches for floor drain stoppers. I realize I should have been more careful taking this apart. My neighbor and I just did his BMW 2002, so I (mistakenly) assumed the Datsun would be the same procedure. That's really bitten me in the ass 🙂 My new chain will be here possibly tomorrow, but I'm sure the brite links won't line up. Thanks in advance for any insight or advice. Edited August 2, 2020 by Duncan Quote Link to comment
banzai510(hainz) Posted August 2, 2020 Report Share Posted August 2, 2020 That’s weird I think the key dowl would be up (12 o clock)and the timmimg dimple in the 3.30 position if you rotated the key dowl up the lower sprocket simple would be in the 330 positionAs what I remember weird. unless some thing is sheared I don’t see why yours is doing this . Maybe this was made wrong? I seen shears key wedges or pins whatever they call them broke once before on Ratsun. Is the timmimg mark on the crack and timmimg plate or pointer match up on front cover at TDC?? If yes then I don’t know why to say. L16/18 is 42 Links L20 44 you can put marks on them or if jap chain will have the marks i would bolt the head one then put the chain and guides then loosely put the front cover on and check the timmimg mark on front cover and the cam if off move it in the correct direction. Quote Link to comment
Duncan Posted August 2, 2020 Author Report Share Posted August 2, 2020 (edited) I can put the pulley on the crank and the timing mark is very very close to TDC. (Save a degree or two) I have the "Keep your Datsun Alive manual" and here's what they say about the crank gears: "The gear will only fit on the crankshaft when inside the gear lines up with the keys in the shaft. The small punch mark (dimple) should be visible on the left side of the gear. (Driver's side)" Then it goes on to say a paragraph later: "Match the position of the crankshaft with the position of the camshaft. The punch mark on the crank gear should be to close to the 3 o'clock position" Does that mean I should rotate the crankshaft 180 degrees off of TDC so the dimple meets the lower brite link? I have to say this is really baffling. In one paragraph, it says the dimple should be where it is now, the next paragraph, it says to rotate the crank to have the dimple meet the brite mark on the chain. That makes no sense to me to move it off of TDC.. If worse comes to worse, I can always pull the head off easily enough, I can double check that cylinders 1 and 4 are up, but I'm 99.9% sure it's right on TDC. I'm not sure what else to do at this point. Edited August 2, 2020 by Duncan Quote Link to comment
banzai510(hainz) Posted August 2, 2020 Report Share Posted August 2, 2020 (edited) I just looked at my book and it shows the woodruft key should be straight up when at TDC. I also looked at a spare motor and it shows up at TDC i would pull the sprocket off and see it that key is sheared compare the distributor drive worm gear there will be 2 or 3 keys on the crank just review my vid again and go by that. Number 1 piston up the key slot should be straight up and the dimple on sprocket will be about 3.15-3.30 posistion That’s the bottom end head the dowl will be up.pick dowl hole number 2 for L20 and the cam will be in the 10 and 2 position Edited August 2, 2020 by banzai510(hainz) Quote Link to comment
banzai510(hainz) Posted August 2, 2020 Report Share Posted August 2, 2020 Unless you turned the crank the key slot should be up at Tdc Quote Link to comment
Duncan Posted August 2, 2020 Author Report Share Posted August 2, 2020 36 minutes ago, banzai510(hainz) said: Unless you turned the crank the key slot should be up at Tdc You really can't see it, but like I said, the pulley notch is right where it should be, and the pistons were in the right position as well. Cam lobes are at 10 and 2, cam sprocket on number 2 and notches all line up there. I wish I understood what Messer says about the dimple being on the left (driver's side) and then lining up the crank with the cam so the dimple is on the right side. That makes NO sense to me whatsoever.. Quote Link to comment
Duncan Posted August 2, 2020 Author Report Share Posted August 2, 2020 (edited) Don't want to be difficult because I appreciate the input, but here's the exact copy from the "Keep your Datsun alive" book. Here's where he says to install the gear, and the dimple will be on the left side. (Where it is now) Please note the last sentence of this paragraph. And then you read this about matching the position of the crank with the cam, the dimple ends up on the other side. Clear as mud, IMHO 🙂 At least right now, I'm good with the top paragraph... I'm not getting where it say to match position of cam with position of crankshaft. Once that's done, the dimple appears to be on the right side at 2 o'clock.. ?? Edited August 2, 2020 by Duncan Quote Link to comment
wayno Posted August 2, 2020 Report Share Posted August 2, 2020 When I look at that photo the key in the crank is at 4 or 5, every photo I just looked at in my book shows the key at 12, it appears that would put the punch mark at around 3:30, now you have to understand that when I use the clock time I am looking at the engine from the front, that book you are reading is talking about everything like your sitting in the drivers seat, but 12 is 12 as that is straight up, so the key is supposed to be straight up, that will put the punch mark on the right when you looking at it from the front of the engine(driver side) like shows in the photos in the book. Quote Link to comment
banzai510(hainz) Posted August 3, 2020 Report Share Posted August 3, 2020 (edited) Going by your 1st photo if your number 1 piston is up all the way then something. As the woodruf key should be straight up stop reinspect i have a feeling you or somebody turned it or the key sheared( I don’t know how) if I Need to redo my vid again let me know but I think it explains everything you need to know daniel and I can see the key slot. It’s in the 4/5 o’clock position and the brute link chain dimple on lower sprocket in the 8 or so position Edited August 3, 2020 by banzai510(hainz) Quote Link to comment
banzai510(hainz) Posted August 3, 2020 Report Share Posted August 3, 2020 (edited) Retake photo from front with the chain on or off and white paint the dimples take photo on head top sprocket at tdc photo of lower sprocket at TDC Edited August 3, 2020 by banzai510(hainz) Quote Link to comment
Duncan Posted August 3, 2020 Author Report Share Posted August 3, 2020 40 minutes ago, wayno said: When I look at that photo the key in the crank is at 4 or 5, every photo I just looked at in my book shows the key at 12, it appears that would put the punch mark at around 3:30, now you have to understand that when I use the clock time I am looking at the engine from the front, that book you are reading is talking about everything like your sitting in the drivers seat, but 12 is 12 as that is straight up, so the key is supposed to be straight up, that will put the punch mark on the right when you looking at it from the front of the engine(driver side) like shows in the photos in the book. Actually, somewhere on that page, he describes sitting in front of the car and looking into the engine bay. I think I'll take the head off and the lower gear stuff and see what I can see. The baffling thing is the pulley and the timing slot. It lines up at TDC, so maybe Heinz is right that possibly the key sheared off. Initially, the head broke a valve spring and was actually running when I pulled it apart... Quote Link to comment
wayno Posted August 3, 2020 Report Share Posted August 3, 2020 (edited) I can see the key in that photo, it is not in the right place in that photo, so if 1 and 4 cylinders pistons are at the top of the deck then the crank is broke. There is no way for that key to be in that position and have the pistons at TDC, not in that photo, I see you said "he describes sitting in front of the car and looking into the engine bay", I am now wondering if the engine is where you are, if it has the head on it I do not think it is at TDC, easy to figure out, remove spark plug and stick long screw driver in there and turn the crank till the screw driver is pushed all the way up as high as it will go, I suspect the key in the crank would be at the top then, might still be 180 out though, do not continue to turn the crank if it jambs as that would likely be a valve hitting the top of a piston. Edited August 3, 2020 by wayno Quote Link to comment
banzai510(hainz) Posted August 3, 2020 Report Share Posted August 3, 2020 Weird how it broke a valve spring. maybe it was just tired. go to Vimeo.com put Hainz Datsun at about 30 mins in you see me install the chain. The woodruf key is up in the 12 o clock position looking straight at it. be honest on most motors the lower sprocket isn’t worn bad and I just leave it.i only have done one and I was lucky it was ez to take out. The other I said fuck it and just replaced everything else as I was having a hard time squeezing it off. Since the sprocket is a small dia they don’t get sharp as fast as the upper. Quote Link to comment
Duncan Posted August 3, 2020 Author Report Share Posted August 3, 2020 Thanks guys. I’ll yank the head off tomorrow and see what’s going on. If rather do that than try to get that lower gear off. Again, there was so much bad work done on this wagon that I am not surprised by anything I find with this vehicle.. Quote Link to comment
banzai510(hainz) Posted August 3, 2020 Report Share Posted August 3, 2020 (edited) I think the crank turned on you as the key and the dimple looks like it’s in the correct position if the whole crank was turned. i hate for you to take the head off and have to get a new head gasket maybe you could slowly rotate the crank counter clock wise where the key is up near 12 o’clock then look thru the spark plug hole to see if you see top of piston. also maybe you could pry the lower sprocket out a CUNT hair and see if the other key is right behind it for the dist worm gear if yes then it’s fine if not the the sprocket rotated cause the key sheared Edited August 3, 2020 by banzai510(hainz) Quote Link to comment
Duncan Posted August 3, 2020 Author Report Share Posted August 3, 2020 I'm going to go grab a gear puller to remove the crank gear, AND take the head off. I really need to see what the 'eff is going on here. I have a real old school parts store near me. I think I paid $11 last time for the gasket, and this guy usually gets stuff in 4 hours or less. I've run into CHip Foose and the Wheeler Dealers guy in there, as well. Fortunately, I have no time pressure... Chances are highly likely I've done something wrong since the wagon has always run. I'm now viewing it as a personal challenge 🙂 Quote Link to comment
banzai510(hainz) Posted August 3, 2020 Report Share Posted August 3, 2020 well have your wagon done up by chip an have it on TV Bam your done Quote Link to comment
datzenmike Posted August 3, 2020 Report Share Posted August 3, 2020 You are all looking at the oil finger and it may not even be on the woodruff key. Don't assume. With head off you should be able to set #1 piston to TDC pretty close. Pull the oil slinger and worm gear off and see if the gear in on the keyway, I'm sure it is but check. Dimple should be 4-5 o'clock, Quote Link to comment
Duncan Posted August 3, 2020 Author Report Share Posted August 3, 2020 (edited) The Overhaulin' and Wheeler Dealer shops are about 1/2 mile from my house. I'll go to Home Depot and regularly see some of the Overhaulin crew there in their T-Shirts. Anyway, glad I took the head off 'cause it was not on TDC, now it is.. Motor on TDC now.. Dimple as it is now.. I had the pulley on facing the wrong way, here's where it is facing the correct way 🙂 Anyway, I had a few people here working on it here with me, and somehow it got rotated. I know I could have put a screwdriver or similar into #1 plug hole, but I like to be absolutely sure about stuff like this, especially since you have to put so much back on before you see if it runs. Oh well, I chalk it up to a good learning experience. If there's a next time, it'll be a breeze 🙂 Edited August 3, 2020 by Duncan Quote Link to comment
Stoffregen Motorsports Posted August 3, 2020 Report Share Posted August 3, 2020 Take this opportunity to set your TDC pointer. Slip the timing cover back on, with the TDC pointer and pulley. Bring the piston to TDC and verify it against the pointer. They are notorious for being slightly off. 1 Quote Link to comment
wayno Posted August 3, 2020 Report Share Posted August 3, 2020 I am confused again, that last photo of the front pulley has the timing notch/mark on the driver side, is that photo of where the notch was with the crank not at TDC? Quote Link to comment
banzai510(hainz) Posted August 3, 2020 Report Share Posted August 3, 2020 (edited) wayno Later L20s motor had the timming notch(only 1) on the right side using a sawtooth timming plate.(I cant open the photos but assume that what your talking about. I seen left sided one also and the early 510 with just a pointer and the 5 notches on the crank pulley if that all is is I then say just leave it somehow it got rotated.?????????????????????????????????? like I said!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! get a good headgasket Edited August 3, 2020 by banzai510(hainz) 1 Quote Link to comment
Duncan Posted August 3, 2020 Author Report Share Posted August 3, 2020 (edited) BTW, thanks to all for the help. I really appreciate it. All you guys posting in this thread are always very helpful to everyone. Wayno, Hainz is right on the L20 timing notch and pointer being on the right side. (Looking at the engine from the front of the car) I don't know if they are all like that, but mine is. 14 minutes ago, banzai510(hainz) said: somehow it got rotated.?????????????????????????????????? like I said!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! get a good headgasket Yep, it was a screwup. User induced FUBAR. I've always used the Felpro head gaskets. This is my first Datsun, but did a LOT of small and big block Chevys back in the day with good success. Edited August 3, 2020 by Duncan Quote Link to comment
wayno Posted August 3, 2020 Report Share Posted August 3, 2020 (edited) 25 minutes ago, banzai510(hainz) said: wayno Later L20s motor had the timming notch(only 1) on the right side using a sawtooth timming plate.(I cant open the photos but assume that what your talking about. I seen left sided one also and the early 510 with just a pointer and the 5 notches on the crank pulley if that all is is I then say just leave it somehow it got rotated.?????????????????????????????????? like I said!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! get a good headgasket The right side is the passenger side and all my l20b and LZ23 engines have that, but that photo has the notch on the pulley on the distributor side of the block(driver side), I have never seen a sawtooth timing plate under the distributor before on an L20b. Edited August 3, 2020 by wayno Quote Link to comment
banzai510(hainz) Posted August 3, 2020 Report Share Posted August 3, 2020 17 minutes ago, wayno said: I have never seen a sawtooth timing plate under the distributor before on an L20b. I have seen one !!!!!!!!!!!!!! under the dist. then theyre are 2 different pulleys one can install and confuse people even more when I say left and right its always looking to the front of the motor ,as when they say otherwise I get confused as the right side is passenger side 1 Quote Link to comment
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