The Lowest compression the 3VZE can run on?
#1
The Lowest compression the 3VZE can run on?
I did compression tests and I guess my cylinders or rings are bad - Around 120 - 130 psi each cylinder.
Im also having misfire problems after a HG rebuild. bad enough that it wont idle and sounds like a lawnmower. I really have checked the timing again and again.. and yes dist.rotor position as well.
I know Im not getting ignition cause the spark plugs and inside of my valve cover smell like gasoline.
Tomorrow Im gonna inspect my distributor and ignitor and cords resistance. But these were never causing a problem before I melted my HG's. (frozen coolant overheat). Its been sitting for the last 2 yrs
Please help guys
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3VZE 92 pickup 4x4 3.0
Im also having misfire problems after a HG rebuild. bad enough that it wont idle and sounds like a lawnmower. I really have checked the timing again and again.. and yes dist.rotor position as well.
I know Im not getting ignition cause the spark plugs and inside of my valve cover smell like gasoline.
Tomorrow Im gonna inspect my distributor and ignitor and cords resistance. But these were never causing a problem before I melted my HG's. (frozen coolant overheat). Its been sitting for the last 2 yrs
Please help guys
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3VZE 92 pickup 4x4 3.0
#4
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Absolutely. You pull less air into the cylinders, so there's less to compress. I've never measured above about 135psi on any engine here at 5000 feet. No way you'll see the 150-170 that the service manual talks about. I don't know why they don't point that out in the FSM. I'm sure plenty of people have torn their engine down for no good reason because of this.
There's a formula for expected psi reduction on a compression test based on altitude, but I don't have it at hand right now. I'll post it if I can find it.
There's a formula for expected psi reduction on a compression test based on altitude, but I don't have it at hand right now. I'll post it if I can find it.
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TK93Runner (12-11-2020)
#5
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Atmospheric pressure at 5,000 ft above MSL is about 83% of what we rich people breathe. https://www.avs.org/AVS/files/c7/c7e...de54f87b9e.pdf Taking 83% of the Toyota-specified minimum (141psi http://web.archive.org/web/200611160.../6compress.pdf ) leaves us with about 118psi as a "minimum" compression result in Denver. (83% of 171 gives about 142psi as "standard," matching RJR's number).
This isn't exact; the 9.0:1 compression is probably adiabatic, and the whole thing is empirical anyway. But this calculation is well within the accuracy of any compression gauge setup.
This isn't exact; the 9.0:1 compression is probably adiabatic, and the whole thing is empirical anyway. But this calculation is well within the accuracy of any compression gauge setup.
Last edited by scope103; 11-03-2016 at 07:44 PM.