Crashtd420 Posted May 29 Author Report Share Posted May 29 8 hours ago, ggzilla said: stainless valves? Are they from Nismo? I believe so but not 100% sure... Quote Link to comment
Crashtd420 Posted June 2 Author Report Share Posted June 2 So in an attempt to save myself what I can where I can, I'm disassembling the head to get it ready to go to the machine shop.... I have gotten to this point and I'm questioning the removal of the inserts that the rocker adjuster thread into... They seem really tight.. I assume they are suppose to come out, but i can't find any information about them or the torque spec they have been tightened too.... Quote Link to comment
ggzilla Posted June 3 Report Share Posted June 3 I cannot see why the rocker pivots would need to removed. Did the machine shop ask for bare aluminum? Quote Link to comment
banzai510(hainz) Posted June 3 Report Share Posted June 3 19 minutes ago, ggzilla said: cannot see why the rocker pivots would need to removed. A machine shop I went to did the same thing, I had a warped head as the cam would not go in straight and when towers torq down cam was tight with NO rocker arms. So they machine the top and bottom.I too didnt want to take the top stuff off. He put it back I did the rockers and cam towers and cam, I place cam in with loose towers and bolted to like 10-13 punds what ever spec is. Just be CAREFUL ,the threads pull ez on the towers. the ones that go in the aluminum. Silver Seal or maybe Partsgeek had cam tower shims. I think you can stack 3 high if remember right. Quote Link to comment
ggzilla Posted June 3 Report Share Posted June 3 So in your case, the shop wanted to mill the cam towers, but you had them skip that step and it was OK? Do the pivots need to come out to mill the top? 6 minutes ago, banzai510(hainz) said: A machine shop I went to did the same thing, I had a warped head as the cam would not go in straight and when towers torq down cam was tight with NO rocker arms. So they machine the top and bottom.I too didnt want to take the top stuff off. He put it back I did the rockers and cam towers and cam, I place cam in with loose towers and bolted to like 10-13 punds what ever spec is. Just be CAREFUL ,the threads pull ez on the towers. the ones that go in the aluminum. Silver Seal or maybe Partsgeek had cam tower shims. I think you can stack 3 high if remember right. Quote Link to comment
banzai510(hainz) Posted June 3 Report Share Posted June 3 (edited) 28 minutes ago, ggzilla said: Do the pivots need to come out to mill the top? good call I cant remember if the pivots were removed or not I was crying not to pull the towers off he said it will be fine and best to do.GGZilla It was that machine shop in down town Renton by the post office. Long since closed. Its a hair place or tatoo shop now. By Old Whistle Stop. He did my first set of kingpins also. Edited June 3 by banzai510(hainz) Quote Link to comment
Crashtd420 Posted June 3 Author Report Share Posted June 3 1 hour ago, ggzilla said: I cannot see why the rocker pivots would need to removed. Did the machine shop ask for bare aluminum? Yes and no.... He said to remove the remaining components, i didn't think to ask about the pivot piece that remains because i didn't think it would be an issue to remove... I assume they need to be removed to set the head flat because the other side will have to be milled to remove the damage... I'm not sure his actual setup. I don't believe the top needs any machining since this issue wasn't due to over heating. Quote Link to comment
Crashtd420 Posted June 3 Author Report Share Posted June 3 I'll probably do the rest of the work needed to to get it to the machine shop and then see what he says.... I also have an old 210 head I might see what it actually take to remove one of those pivot bases from that before I mess up my w53 head... Quote Link to comment
ggzilla Posted June 3 Report Share Posted June 3 20 hours ago, Crashtd420 said: the inserts that the rocker adjuster thread into... ...i can't find any information about them or the torque spec they have been tightened to I don't see that spec either The 1977 620 FSM says: Rocker pivot lock nuts 5.0 to 6.0 kg-m (36 to 43 ft-lb) I expect the rocker pivots themselves would have to be put in tighter or they could accidently turn out with the nuts 1 Quote Link to comment
datzenmike Posted June 3 Report Share Posted June 3 The cam towers and the valve cover gasket surface are the same. It would be hard to mill the towers and not the valve cover gasket surface. Usually the cutter skims the entire surface and those pivot inserts are in the way. 1 Quote Link to comment
ggzilla Posted June 3 Report Share Posted June 3 2 hours ago, Crashtd420 said: I also have an old 210 head I might see what it actually take to remove one of those pivot bases Good idea. Remove the nut first, then use a torque wrench to undue the pivot. Then you got your torque spec Quote Link to comment
Crashtd420 Posted June 4 Author Report Share Posted June 4 57 minutes ago, ggzilla said: Good idea. Remove the nut first, then use a torque wrench to undue the pivot. Then you got your torque spec This almost worked out, didn't seem to take too much to remove them from the 210 head... but i feel like I was missing the click or something to figure out the torque amount.... I tried retightening it to match how much it took to loosen... by that method i torqued it to 40 ft lbs and it felt about the same to release..... The ones in my w53 head were definitely more than that so I might just use 40 for the installation and be good with it.... I ended up using heat on the outside of the head and was able extract all of the pivot bases. Quote Link to comment
mainer311 Posted June 4 Report Share Posted June 4 2 hours ago, ggzilla said: Good idea. Remove the nut first, then use a torque wrench to undue the pivot. Then you got your torque spec It doesn’t work that way. Especially if they’ve been installed for a long time. I removed the pivots from my W58 head, no issues. Used a 6 point socket that I machined flat in the end (no internal chamfer left) and a breaker bar. 2 Quote Link to comment
Crashtd420 Posted June 4 Author Report Share Posted June 4 Next up is determining my course of action with the head... I have to get it milled no matter what but I'm concerned with the quench area of cylinder 4.. its so banged up I'm wondering if I should have that welded first instead of just trying to grind the edge and mill it to clean... Vs the bad one Quote Link to comment
ggzilla Posted June 4 Report Share Posted June 4 1 hour ago, Crashtd420 said: The ones in my w53 head were definitely more than that so I might just use 40 for the installation Well, the torque spec for the nuts is up to 43 lb-ft, so the pivots need to be torqued tighter than 43 Yes, the method won't tell us the actual torque specification, but it's better than nothing since we don't know what the actual torque spec is ... 1 hour ago, mainer311 said: t doesn’t work that way. Especially if they’ve been installed for a long time. 4 hours ago, ggzilla said: Good idea. Remove the nut first, then use a torque wrench to undue the pivot. Then you got your torque spec 1 Quote Link to comment
ggzilla Posted June 4 Report Share Posted June 4 1 hour ago, Crashtd420 said: I'm concerned with the quench area of cylinder 4.. its so banged up I'm wondering if I should have that welded first instead of just trying to grind the edge and mill it to clean... It is unusual ... my first thought is yes, grind the edge smooth. I would check for cracks in the valve seat as well Quote Link to comment
bananahamuck Posted June 4 Report Share Posted June 4 Little late but yeah, they are weird tight,, like the treads are galling, it's unnerving but somewhat normal --ish I think no matter what the actual "spec" they aint loosing up . 1 Quote Link to comment
ggzilla Posted June 4 Report Share Posted June 4 7 hours ago, ggzilla said: The 1977 620 FSM says: Rocker pivot lock nuts 5.0 to 6.0 kg-m (36 to 43 ft-lb) I expect the rocker pivots themselves would have to be put in tighter or they could accidently turn out with the nuts Found this web page: Rocker arm pivot lock nut - 40-44 ft-lbs (5.5-6.0 kg-m) Rocker pivot Bushing - 58-87 ft-lbs Dunno what the bushing is ... searching ... found it in the parts catalog: * 13215-A8600 ROCKER PIVOT BUSHING * 13255-A8600 ROCKER PIVOT RETAINER from the diagram it looks like Datsun calls the pivot the "bushing" 1 Quote Link to comment
Crashtd420 Posted June 4 Author Report Share Posted June 4 3 hours ago, ggzilla said: It is unusual ... my first thought is yes, grind the edge smooth. I would check for cracks in the valve seat as well Just a reminder this was from an external piece of metal that found its way in getting hammered in the quench area.... The picture doesn't show the damage properly.... The intake seat might have a mark but it should be ok, intake is getting an oversize valve so its getting cut regardless. If there is an issue the machine shop can deal with that.. And that torque spec of 58 to 87 is more inline with how tight the w53 head felt... I'll probably shoot for 60 for reinstall then.... Quote Link to comment
iceman510 Posted June 4 Report Share Posted June 4 10 hours ago, ggzilla said: Found this web page: Rocker arm pivot lock nut - 40-44 ft-lbs (5.5-6.0 kg-m) Rocker pivot Bushing - 58-87 ft-lbs Dunno what the bushing is ... searching ... found it in the parts catalog: * 13215-A8600 ROCKER PIVOT BUSHING * 13255-A8600 ROCKER PIVOT RETAINER from the diagram it looks like Datsun calls the pivot the "bushing" The pivot is actually the "ball" part with it's threaded stud, which should not have a torque value, just the nut that holds it. The pivot screws into the bush or bushing. Just like a plumbing bushing that has external and internal threads. Quote Link to comment
Crashtd420 Posted June 10 Author Report Share Posted June 10 Been working on the engine, I got all the pistons out... just need to remove the rings and rods.... I need to weigh the pistons so I can match the weight when I prep the damaged one.... Unfortunately life has other plans, wife's subaru started acting up again... I have a bad feeling its the head gasket again...there has to be a low spot that I could not find or feel with a straight edge and feeler gauges.... so if I do the head gaskets again I'll send the heads to the machine shop regardless... Then as I left the house with the datsun this morning I lost all power... thankfully I wasn't far from home so I walked back for some tool and my nissan and headed back to figure it out . I found a blow fuse that feeds power to the switches and relays in my truck... I was able to get it started and drove about 20 ft before it ran out of gas but I got into a parking lot this time atleast.. No power to my fuel pump.... hum... (Remember not a factory wiring job) Unable to find the cause, since I really needed to get to work, i rigged up an old dirt bike gas tank in the engine bay and gravity feed the carburetor enough to get home.... So my other engine is back on the back burner... Hopefully the datsun is something stupid and easy.... So I can get going on the subaru..... Choices are: Rebuild again for 500 to 1000. Replacement used 1800 to 3000, Remanufactured for about 4000.... Quote Link to comment
ggzilla Posted June 12 Report Share Posted June 12 On 6/10/2025 at 6:00 AM, Crashtd420 said: So I can get going on the subaru..... Choices are: Rebuild again for 500 to 1000. Replacement used 1800 to 3000, Remanufactured for about 4000.... Start with diagnosing the problem. For a suspected head gasket problem, do a compression check, a cooling system pressure check and a leakdown test. Best case scenario, it will prove it's not a head gasket. Another scenario: only one head gasket has a problem, that cuts your expense in half Quote Link to comment
Crashtd420 Posted June 12 Author Report Share Posted June 12 (edited) 6 hours ago, ggzilla said: Start with diagnosing the problem. For a suspected head gasket problem, do a compression check, a cooling system pressure check and a leakdown test. Best case scenario, it will prove it's not a head gasket. Another scenario: only one head gasket has a problem, that cuts your expense in half I went through all of that diagnostic about 8 months ago.... this is the exact same way it started the last time.... Which is what leads me to believe i missed something.... Since it has been good for the last 8 months i can only assume its the head gasket sealing surface... If it was a crack or something else like that it would have failed right away after i replaced the head gaskets last time... I should have had the heads cut but feeler gauges and straight edge said I was good....When it happens It has always been low coolant and thankfylly she has never truly over heated the engine... Edited June 12 by Crashtd420 Quote Link to comment
Crashtd420 Posted June 13 Author Report Share Posted June 13 Atleast I figured out what happened to the datsun .. The wiper arms under the dash decided grab the trigger wire from my dash switch that controls the fuel pump relay. It grabbed a couple others but they didn't get cut, I had to remove the wiper arm in order to get the wires free... Now the truck will run but my fuel pump only works off the switch. I have an oil pressure switch that controls the fuel pump normally, need to see what's up with that connection now, possibly another blown fuse... TBD..... If this isn't enough to drive me crazy my wife said the VW bus was acting like it had no power... 1st gear can be a little finicky and I think she is accidentally grabbing 3rd.... So I took it for a ride, needed to get something anyways, everything seemed fine, power seemed good, even tried a couple hills, and the next thing I know the engine is running too hot... I bought a dipstick that monitors the oil temp, If it get too hot it makes the oil light flicker, and eventually go on.. this is also connected to the fuel pump relay so if oil is getting hot the bus will stall out from lack of gas before the heat becomes a major issue.... Seems hot days and puttering around town in stop and go traffic doesn't cool an air cooled engine too good.... Luckily upgraded parts can be added.. We ordered and oil cooler with all 8an lines and fittings... New high flow oil pump with in and out fittings to go to the cooler... I'm also adding a remote oil filter since the bus only has a screen. Last item is a thermostat block... It recirculates 90% of the oil with only 10% going through the cooler. This keeps all the oil at the same temp, once the temp reaches 180 then it opens and runs 100% through the cooler and the fan will turn on.... Quote Link to comment
Crashtd420 Posted Friday at 11:56 PM Author Report Share Posted Friday at 11:56 PM Found the other connection that was broken.... now i just need to secure the wires and extra relays and stuff I have crammed into the glove box area.... This has been something I have needed to redo for a long time... I'll still need to deal with it more in the future.... Also bus seemed better for the wife.. took it out tonight and temperature was fine... i think on hotter days we need to drive it a little different.... seems more rpm equals cooler temps because it spins the fan faster, which blows across the engine and factory oil cooler.... So the idea is more rpm at slower speeds vs putting around... still doing the added oil cooler for traffic reasons either way... Quote Link to comment
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