Do-anything LJ build advice
- Thread starter Marklar1983
- Start date
First long (15 minutes) drive today. Developed valve train noise around 10 minutes in. How bad is this, and what do I need to check?
https://share.icloud.com/photos/0e5rsMmnAi4R5lwuHwpifXvHA
https://share.icloud.com/photos/0e5rsMmnAi4R5lwuHwpifXvHA
You'll need to check your oil pressure with a manual gauge.
Pull the valve cover and check for loose pushrods/rockers or other issues. Is oil coming out of all the pushrods as it runs?
Is there glitter in the oil?
Pull the valve cover and check for loose pushrods/rockers or other issues. Is oil coming out of all the pushrods as it runs?
Is there glitter in the oil?
I added a wet oil pressure gauge with this rebuild; pressure is good, 20-60 psi.
No loose parts.
A tiny bit of glitter in the oil, definitely normal for a new engine start.
Noise is a tap/knock at half the crank rpm, so it’s definitely valve train, not pistons. Stethoscope supports a faulty lifter. I’m getting a set of Hy-Lift Johnson lifters from Russ to replace the Comp Cams lifters I put in, hopefully that fixes it.
Sounds like a well reasoned assessment. I concur.
However, your planned fix will not work. The only way to fix that is with a Hemi…
Well, shit. Replaced the lifters, and still have the same noise in the same place. Stethoscope picks it up best on the #3 cam bearing. Best guess, there’s either a lifter sticking, or cam damage.
Any ideas for what I can investigate before tearing down?
Any ideas for what I can investigate before tearing down?
Found the source. #3 cam bearing is fucked. 
Found the source. #3 cam bearing is fucked.
View attachment 605686View attachment 605687View attachment 605688
DAMN that SUCKS.... And I know all about finding out your newly built engine is broke/ruined/FUBAR. Hope the cam isn't wiped out also... Not familiar with the 4.0 heads that much but can it be bored out and a oversized bearing be pressed in?
I am hopeful (but not optimistic) that, given there’s only a couple hours on it, the only damage is the bearing. Won’t know until it’s all apart.
Make sure you check that the cam is straight when it comes out. Jezza went through this in his build recently. You should check his build
Unlucky. All the bearings show damage or contamination. Cam, crank, and rods. Since everything needs cleaning, I’m tempted to have the cylinders honed again and put in fresh rings. Worth it, or no? Anything else I should check or replace?
Hom much run time on the engine? That will determine if you should have the cylinders honed again but also can you still see the hone marks in the cylinders? If they are still visible then NO you don't need to rehone the cylinders.
How did all the bearings get wiped out though. You said you had no coolant in oil and good pressure?
Bits of the cam bearings circulated to the other bearings with the oil.
She’s proper fucked. Need to go to a different machine shop and get bores measured, probably honed, and at least a new #6 piston. Cam and crank journals also need polishing.
DAMN....
Yep, honed for sure at a minimum if the cylinders measure out OK... Hopefully it didn't do any serious damage....
I'm having flashbacks........
I have high hopes for the same, but it seems everything related to machining on this project has gone wrong, so my expectations are pretty low.
Pretty sure I have a root cause. Nominal bore size should be 9.935” (overbored +0.060”). All cylinders measure ~0.0015” UNDERsize, as measured with a calibrated bore mic I borrowed from work. 
Pretty sure I have a root cause. Nominal bore size should be 9.935” (overbored +0.060”). All cylinders measure ~0.0015” UNDERsize, as measured with a calibrated bore mic I borrowed from work.
View attachment 609458
Did friction overheat and warp the block? I'm very curious about the cam bearings woes
The machinist who put my short block together for me was pleasantly surprised my mains were straight. I guess that applies to cam bores too?
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