That takes great pictures.way better than mine.do you have a link?
4.6 stroker engine rebuild nightmare story (Cylinder 2 at 35 psi)
- Thread starter Carve
- Start date
That takes great pictures.way better than mine.do you have a link?
You can get a tool called a valve holder. It's basically a hose that connects an air compressor to the spark plug hole. If you put each piston at TDC and use that tool you can determine where the air is escaping. That tool is much cheaper than a leakdown tool. The scoring doesn't look that bad to me. It looks like marks left by the ring ends. You sometimes see that in freshly honed cylinders.
OP
Oh it looks like it was actually more like $40. Pretty good value. However, it has limited angles it can do in a cylinder. I wish the front could be steared around, or if it had a sidways or rearward facing camera to inspect the valves. Can't complain for $40 though! https://www.amazon.com/dp/B07MV6X4M4/?tag=wranglerorg-20
OP
That's a good idea! I mean...I already know it's not holding pressure. The question is more "where" than "how bad".
Basically does it come out of the valve cover with the cap off,the intake or the exhaust pipe.compare cylinders and you'll find out in a hurry. Tdc compression for each cylinder. Be careful with breaker bars on the crank bolt. The air will want to send the piston to the bottom
If the OP is using a screw in compression tested he can pull the shader out of the hose and use it to put air in the cyl.
OP
Thanks. Is there any way you recommend I prevent the engine from turning over while doing this?
Also...my dry vs wet numbers are still 11 to 31% apart. However, the engine only has about 40 miles on it so maybe that'll improve with break in.
One more thing...after burning my oil off from my wet test, since I had all my tools out, I pulled everything apart again and did a 2nd dry test. Most of the numbers were up quite a bit! Maybe it's because I did it so much faster and the engine was warmer?
Cyl Dry1 Dry 2
1) 95 112
2) 35 50 (Major improvement, but since this one misfires so bad maybe it was still a little wet)
3) 89 89
4) 97 93 (weird- this one went down)
5) 101 117
6) 94 112
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#5 cylinder is 180 degrees from #2 this could be the cause of the pcm picking up this other misfire. The scoring marks may be a little concerning depending on how deep they are. I would be more concerned about the little balls on the piston. Those could be valve material due to detonation. I would put some air in each cylinder with it at TDC and see if it is coming out intake or exhaust.Can rotate you camera to look at the valves? In the end the head needs to come off.
Jezza makes a great point to follow up with.checking timing chain alignment would be next for me.
If the head hasn't had a valve job I'd pull it and have it done regardless of findings.
If the head hasn't had a valve job I'd pull it and have it done regardless of findings.
You do not have enough compression to run the motor. Break in will not help. You may want to check the cam timing on this, if this is how it ran when you got it back after the engine install.
OP
All right guys...just blew air into cylinders 2 and 5 (the worst and best compression, respectively...but both are reporting a misfire). Cyl 2 is blowing air out the throttle body. Cyl 5 is blowing air out of the breather tube on the valve cover. This guy royally screwed me.
Just to verify, as long as all the oil is circulated, holding the engine at around 2k rpm until it warms up would never, under any scenerio, "fry the rings", right?
Any tips on how to take this guy to small claims and actually collect? Have you ever heard of collecting extra due to a mechanic dragging their feet and, ultimately, costing you the use of your vehicle for almost a year? I mean...insurance and tire degradation alone is probably $1000, not to mention the intangibles (no Jeep trips, no extra vehicle when I have visitors, forcing them to rent a car, massive depreciation over the last year, death threats, etc.)
Just to verify, as long as all the oil is circulated, holding the engine at around 2k rpm until it warms up would never, under any scenerio, "fry the rings", right?
Any tips on how to take this guy to small claims and actually collect? Have you ever heard of collecting extra due to a mechanic dragging their feet and, ultimately, costing you the use of your vehicle for almost a year? I mean...insurance and tire degradation alone is probably $1000, not to mention the intangibles (no Jeep trips, no extra vehicle when I have visitors, forcing them to rent a car, massive depreciation over the last year, death threats, etc.)
You need to follow the cam break in procedure first. Usually around 2k for 20 min. You didn't hurt the rings doing normal break in.
Hopefully its salvagable.but it probably does need to come out and go back on a stand
Hopefully its salvagable.but it probably does need to come out and go back on a stand
OP
With what your describing it does not seem good.... Built hundreds of engines for Toyota over the last 40 years. I would do complete tear down if it was mine. JMO
Just to verify, you are cycling the mill to close both intake and exhaust when you test each cylinder, correct?
100 percent this..even if for some reason the compression numbers came up on the 2 cylinders are you going to be comfortable with the work done? I wouldn't and would accept this as a lesson learned. Sorry you got taken it sucks
OP
Yeah- I was verifying with the borerscope. I watched the piston move up with both valves closed. You can see the line where it needs to stop. The valves are a little blurry but I watched the intake close before the piston moved up. I even took a video in case I need to show in court that I was doing it properly
OP
OP
Any ideas what might've happened to make brand new rings seal so poorly? Maybe it was machined .030" over instead of .020"? Rings damaged due to shoddy installation procedure? Other?