dieselfume
Member
Started tearing down the 14,000+houred 404 in our 76 4630.
Figured I'd take the head off first to get it sent out to the machine shop while I did the front cover and cleaned things up and re-assembled.
The valvetrain looked good, when I went to remove the head I had a broken head bolt that's been busted for awhile. it's broke off flush with the block deck and looks pretty rusty. I soaked it down with penetrating oil but I'm not sure how this will work out.
The cyl walls have no crosshatch left, but no visable scoring and a healthy ridge. pistons are all intact and have no cracks.
so far I don't see any cracks on the head except for at the hole where each nozzle protrudes there's about a 1/8-1/4 inch crack running back... no cracks anywhere else that I see right now. I'll know more when I get it completely buffed off.
I'm short the correct deep 15/16 socket to remove the nozzles, so I'll have to get that later, or have the machine shop do it.
I haven't got the radiator pulled or front cover off yet, but I'll try to get at that tomorrow.
My questions are-
How should I best go at this broken head bolt?
my instinct tells me to try and weld a nut on it, but I've never had one break off on the block deck before.
How do I "pin" this engine on TDC for valve adjustment purposes, and how do I correctly re-time the crank/cam/IP once the front cover is apart?
What are the specs for head bolt torque, and should the head bolts be replaced? what about valve lash specs?
Anything else I should be looking at before I order more parts?
I'll pull the lifters tomorrow to make sure the cam and lifters are good. didn't have time today.
Thanks!
DF
Figured I'd take the head off first to get it sent out to the machine shop while I did the front cover and cleaned things up and re-assembled.
The valvetrain looked good, when I went to remove the head I had a broken head bolt that's been busted for awhile. it's broke off flush with the block deck and looks pretty rusty. I soaked it down with penetrating oil but I'm not sure how this will work out.
The cyl walls have no crosshatch left, but no visable scoring and a healthy ridge. pistons are all intact and have no cracks.
so far I don't see any cracks on the head except for at the hole where each nozzle protrudes there's about a 1/8-1/4 inch crack running back... no cracks anywhere else that I see right now. I'll know more when I get it completely buffed off.
I'm short the correct deep 15/16 socket to remove the nozzles, so I'll have to get that later, or have the machine shop do it.
I haven't got the radiator pulled or front cover off yet, but I'll try to get at that tomorrow.
My questions are-
How should I best go at this broken head bolt?
my instinct tells me to try and weld a nut on it, but I've never had one break off on the block deck before.
How do I "pin" this engine on TDC for valve adjustment purposes, and how do I correctly re-time the crank/cam/IP once the front cover is apart?
What are the specs for head bolt torque, and should the head bolts be replaced? what about valve lash specs?
Anything else I should be looking at before I order more parts?
I'll pull the lifters tomorrow to make sure the cam and lifters are good. didn't have time today.
Thanks!
DF