Idaho Hillbilly Posted February 28, 2014 Report Share Posted February 28, 2014 Hello, long time lurker, first real contribution to the forum. So, a couple of years ago, I purchased a 521 that I had planned to do a long term restoration on. I drove it for a few months and it developed a rod knock. I ended up parking it and a few months later it was vandalized by some yahoos to the point that it was not salvageable (or at last not cost effective). I ended up hauling it to the scrap yard. Fast forward another year and I was in the market for another Datsun. This time I decided that a King Cab was in order for my 6'2" frame. Seeing how I live in the middle of no where and I had little money to spend, my options were going to be limited. I finally came across one almost 3 hours away, listed with a blown head gasket for $500. The pics looked decent, body looked straight with not much rust. The poster confirmed most of this through emails, going so far as to say the bed was "straight as an arrow". Anyways, after a 3 hour drive in nasty slushy roads I arrived to see my prize. It turned out to be pretty heavily rusted in the rockers and door bottoms (floors are solid though!) and the paint is bubbling in quite a few areas around the rest of the body and bed. The interior was pretty shot and the tires are beat. It is rocking a sweet body lift though :D So, I ended up paying $350 for it and dragging it home. It wouldn't start at all, so I figured I'd start with a compression test. Cylinders 1 and 4 both had about 160psi. Cylinders 2 and 3 both had 0 psi. That was a little discouraging, but I had hopes for a drastic head gasket failure.This, coupled with spark plugs in 1 and 2 that had about .000001 gap all contributed to the no start I'm sure! haha, The tear down began and as it turns out, there was a pretty good failure between 2 and 3! So, now that I've blabbed through that, on with the important stuff: OICS! IMG_20140227_101809_939 by jmbecker25, on Flickr IMG_20140227_101756_144 by jmbecker25, on Flickr IMG_20140227_101824_251 by jmbecker25, on Flickr Just a slight failure... IMG_20140227_161144_414 by jmbecker25, on Flickr IMG_20140227_161227_991 by jmbecker25, on Flickr IMG_20140227_161336_855 by jmbecker25, on Flickr And does anybody have even the slightest idea what this key slot would be for?!?!?!?! IMG_20140227_161702_461 by jmbecker25, on Flickr 2 Quote Link to comment
ggzilla Posted February 28, 2014 Report Share Posted February 28, 2014 Good deal for $500! Put a straight edge on the head, and if you can slip a 0.004 feeler in get the head milled. Otherwise just put a new gasket on. 1 Quote Link to comment
darrel Posted February 28, 2014 Report Share Posted February 28, 2014 key slot most likely for some kind of alarm. Check for extra wires. 1 Quote Link to comment
Jester Posted February 28, 2014 Report Share Posted February 28, 2014 Not surprised to see the center of the head gasket missing with 0 psi in 1&2. Overall it looks like a decent truck for the price. 1 Quote Link to comment
Idaho Hillbilly Posted February 28, 2014 Author Report Share Posted February 28, 2014 Yeah, I'll be checking the head tomorrow. I've done everything but pull the interior panel behind that key cylinder and can't see anything so far. Definitely a good pick at $350. I'll be needing doors and rocker panels though and lots of interior work! 1 Quote Link to comment
abbylind Posted March 1, 2014 Report Share Posted March 1, 2014 Thats definitely an alarm key..I used to have one on my 74 620 4X4 1 Quote Link to comment
Idaho Hillbilly Posted March 1, 2014 Author Report Share Posted March 1, 2014 Good to know about the alarm. That'll disappear at some point then. Rebuilt the carb yesterday. Every single adjustment was WAY off. I can't believe this thing was even running before the head gasket issue between the carb, two plugs with no gap and several backed out intake bolts. Going to try and get the head back on today, but its only suppose to be 16° and I'm working outside, so maybe not! Haha 1 Quote Link to comment
Idaho Hillbilly Posted March 3, 2014 Author Report Share Posted March 3, 2014 Anybody know how much you can machine off the head? Its open chamber if it matters. 1 Quote Link to comment
]2eDeYe Posted March 3, 2014 Report Share Posted March 3, 2014 I've seen them halfway through the casting numbers :lol: Nice looking truck, should clean up real well. 2 Quote Link to comment
Jester Posted March 3, 2014 Report Share Posted March 3, 2014 Just keep in mind that whatever you machine off the head surface needs to be added under the cam towers. 1 Quote Link to comment
Idaho Hillbilly Posted March 3, 2014 Author Report Share Posted March 3, 2014 Just keep in mind that whatever you machine off the head surface needs to be added under the cam towers. That's an interesting thought. A few thousandths will really affect chain tension or is there something else I'm missing? Where would one find these "shims"? 1 Quote Link to comment
Z-train Posted March 3, 2014 Report Share Posted March 3, 2014 Do not use the shims.They change rocker geometry.For a U-67 casting the following numbers apply: New:4.26 minimum : 4.245 Other heads will be the same or similar. If there is enough "head" left,use the advance holes on the cam gear-that's what they're there for. 1 Quote Link to comment
Idaho Hillbilly Posted March 4, 2014 Author Report Share Posted March 4, 2014 Sorry, guess I'm being dumb. What do the 4.26 and 4.245 #s relate to? I understand that if the head drops, there will be some added "slack" to the chain, but I'm missing why that would need compensated for. It seems like the tensioner would just soak it up? As long as piston/valve clearance stays good, right? 1 Quote Link to comment
ggzilla Posted March 4, 2014 Report Share Posted March 4, 2014 That's why its a bad idea to mill the head "just in case". Only mill it if warped. It can be up to 0.0039 from flat and per Datsun is good. No shims or reindex of cam needed. 1 Quote Link to comment
Idaho Hillbilly Posted March 4, 2014 Author Report Share Posted March 4, 2014 Got that part :) I don't have a quality straight edge to measure with, but in the area of the head gasket failure, there is easily enough roughness to feel with your finger and it is visible. I'll be visiting the machine shop tomorrow. Is there a good source for the material to raise the can towers? 1 Quote Link to comment
Z-train Posted March 4, 2014 Report Share Posted March 4, 2014 Those numbers are from the bottom of the head to the top surface of the head where the rocker cover mates to it.Have the machine shop measure head height and if it is with in spec(they'll have the spec for that head),then take up the chain slack using the advance holes in the cam gear.THe tensioner is NOT designed to take up a lot of slack. 1 Quote Link to comment
Idaho Hillbilly Posted March 4, 2014 Author Report Share Posted March 4, 2014 Well, head was already down to 4.240 when I dropped it off. Did some searching and found Fuel Pro makes a head gasket shim that is .020" thick. The guy at the machine shop said he has used them on Yotas with good results so that's what I'm going to try. The part # is 21178SP for anyone interested. 2 Quote Link to comment
Idaho Hillbilly Posted March 7, 2014 Author Report Share Posted March 7, 2014 Well, here is a picture of the cleaned and resurfaced head. I've got the manifolds and everything back on it now, just waiting for that spacer to show up for reassembly. There are a few rough spots in the block that i'm a little concerned about, but I don't have the time or means to pull this engine right now. Also, I have a 2.3l turbo motor from a ford turbo-coupe I plan to swap in possibly this summer, so its just gonna go back together as-is. Untitled by jmbecker25, on Flickr 1 Quote Link to comment
Idaho Hillbilly Posted March 7, 2014 Author Report Share Posted March 7, 2014 Here's a pic of the turbo motor that will be swapped in. ENGINE by jmbecker25, on Flickr and here's one of the 521 that was vandalized and then crushed. Untitled by jmbecker25, on Flickr 1 Quote Link to comment
Labdork Posted March 8, 2014 Report Share Posted March 8, 2014 There was just a thread about the Ford 2.3 a few weeks ago! Personally I love that motor. Almost bought an XR4Ti back in the day. The SVT Mustang has a bit of a following, too. Would haul ass in a 620. PM me if you're up in Spokane.. 1 Quote Link to comment
Idaho Hillbilly Posted March 9, 2014 Author Report Share Posted March 9, 2014 Huh, missed that thread.... didnt come up in search either. Miss anything good? I've got a pretty thorough Ford background. I was a senior master tech for them. Spend most of my life under the hoods of diesels though. I'll actually be in Spokompton Wednesday, but just to catch a plane. My spacer is in and waiting for me at the post office. I'll pick it up in the busyness that is already tomorrow and hopefully start reassembly! Quote Link to comment
bonvo Posted March 16, 2014 Report Share Posted March 16, 2014 from what im seeing in the pics you shouldnt need any shims or spacers or anything like that you can still see all the numbers on that head doesnt even look like its been surfaced Quote Link to comment
Idaho Hillbilly Posted March 16, 2014 Author Report Share Posted March 16, 2014 I'm not that familiar with these engines. From what I've seen, other people run them without shimming the towers or the head.... I know that you'll end up with some degree of cam retarding by doing that, just not sure how much. The shim arrived at my house right before I left town. I wont be back for another 2 1/2 weeks and then I'll get back to reassembly. I'll be installing the shim "just because". Partly, because I'm curious to see how it works :D 1 Quote Link to comment
Idaho Hillbilly Posted January 2, 2015 Author Report Share Posted January 2, 2015 For follow-up, the shim ended up working excellent. I had zero issues and the truck ran great afterwords. I then sold it soon after and have no idea how its doing now. I just had open ended threads and wanted to finish it up in case someone else looks later. Thanks all. 1 Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.