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I'm putting things together after I changed my head gasket... everything is going great then bam, I cracked this part while tightening these screws. I pulled the valve train to do work on the head. So I had a couple questions. Any ideas why this happened? And can I JB weld where it cracked? I googled this question and got mixed results. I've looked for just the part I cracked, but it seems like I have to buy the entire assembly.
Car is a 1996 Honda Civic Coupe EX. The crack is towards the bottom of the pic... can't miss it.
You need another complete head. You cannot just replace the end cap where the dizzy mounts. The cam journals are unique and line bored in each head specifically.
You need another complete head. You cannot just replace the end cap where the dizzy mounts. The cam journals are unique and line bored in each head specifically.
Is it possible to put a new valve train on and get it line bored?
I know it's not worth it, I just know it should be possible to line bore it true.
...I cracked this part while tightening these screws... Any ideas why this happened? And can I JB weld where it cracked?
best guess, the tightening sequence wasn't followed. can you confirm?
since it's trash anyway you could try JB Weld or an aluminum specific casting repair epoxy. Devcon is one of them but it's hard to find in small quantities. due to the location of the break, most of the stresses will be taken by the fasteners anyway. on top of that, older non-vtec engines had this as a separate piece. see...
if you do attempt it, everything needs to be very clean and oil-free. follow package instructions and bolt down and torque to spec (and per the sequence) to let it cure in place. it may not work, but this will likely give the best chance of success.
I would try putting it together as two pieces, which as @hondamark said, is how the non-VTECs are made. The part at the very end really just provides a place to mount the distributor, it isn't under much stress. Worst case you'll need a new head, which is where you are now.
It's important to make sure the dowel pins are going into their holes properly as you turn the large bolts to bring down the cam caps.
best guess, the tightening sequence wasn't followed. can you confirm?
since it's trash anyway you could try JB Weld or an aluminum specific casting repair epoxy. Devcon is one of them but it's hard to find in small quantities. due to the location of the break, most of the stresses will be taken by the fasteners anyway. on top of that, older non-vtec engines had this as a separate piece. see...
if you do attempt it, everything needs to be very clean and oil-free. follow package instructions and bolt down and torque to spec (and per the sequence) to let it cure in place. it may not work, but this will likely give the best chance of success.
otherwise... new or good used head.
I’ll give the Devcon a shot. This is more of an extra car so I can experiment a bit. I’ll post how it ends up... thanks
If I do try to epoxy this and run it, is there anything else I can cause more damage to if the repair doesn't work? I don't want to cause more harm when I can just buy this for $80...
Is it possible to put a new valve train on and get it line bored?
I know it's not worth it, I just know it should be possible to line bore it true.
But a new used head should be no more than $100.
Yes, it is possible to repair this head, but you would have to be emotionally attached to it because the fix would likely be more expensive than a good used core. Re-line honing the cam journals would require a replacement part for the damaged one, cutting a few thousandths off all of the caps in the cam bridge, re-installing the cam caps and torquing them down, line honing the cam journals to factory spec, re-assembling the head completely and then re-installing the head on the block. Since the centerline of the camshaft will now be closer to the crankshaft, one would have to either install an adjustable cam gear to advance the cam slightly for proper operation (and potentially create a fix to increase the tension on the timing belt since there will be additional slack in the whole system), or to increase the head gasket thickness to counter the cam centerline change... although this may drop the compression ever so slightly.
Again, a LOT of work and expense just to fix it... did I mention "replace the head" ?!?
Maybe you fix it IF the head has had a ton of money already dumped into it... CNC port work... a 5-angle racing valve job... replacement valve seats that sit proud to reduce valve shrouding... something well beyond stock. It just doesn't make sense to do this to a factory stock head.
Last question guys.. for this project. This bolt marked with the red arrow. It just keeps turning and doesn't seem to tighten. I'm all nervous now after I screwed up. All the other bolts are torqued. Just keep turning it? What is this bolt for?
Run it, that is not a critical dimension. The cam cams are all doweled and still connected. That broken off piece ONLY supports the distributor and o-ring seal. NBD. Bolt it all down including the broken off piece just remove any loose pieces.
Edit: Oh wait, that is the oil supply galley broken off just under that bolt with the green colored head. She is junk.
The threaded hole for that is likely reamed out. You can get thread inserts for it but I would replace the head if I were you. You can find a good reman head on eBay for under $300.
02-13-2019, 03:32 PM
Cracked my valve train.. can I JB weld?
