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#16
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, on a 4-stroke engine you will go past top dead center twice with one revolution of the crankshaft.you were going to have to be sure that it is on the compression stroke and not the exhaust..ugh.. I'm terrible at explaining things. Look up on the Internet locating top dead center on a 4-stroke.
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#17
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And if you set your cam out of phase during reassembly I would be careful about rolling it over until someone chimes in that knows more about these.
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#18
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Valves are stuck open or not sealing, why? Lord knows...
__________________
1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily 1992 Mercedes 300D 2.5 202,000 - Pure junk 2000 Mercedes E320 Black - 136,000 miles - Needs repair Don't forget to grease the screw and threads on the spring compressor. |
#19
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Quote:
Can't imagine that OP has enough compression leaking to show up as zero on a compression tester, but I would not be surprised to see this engine producing low power due to the valves. Just my 2¢. Something has to be holding the valves open in this case. If you have new rings, new cylinder sleeves, new head gasket, and everything is torqued correctly, there is nowhere for the compression to go but out the valves. I am assuming you have the glow plugs installed. Roverswap, what all have you done for this rebuild?
__________________
Milan Brown 1979 240D, rebuilt OM617.952 turbo diesel, rebuilt 722.315 transmission - engine spun a rod bearing 1979 300SD, ~90k original miles, all stock |
#20
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Start with the basics. Are the accessories on the front of the engine turning? Try cranking with the oil cap off and make sure the cam is actually turning?
Definitely a leak down test next. Interested in seeing the results on this one.
__________________
617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap |
#21
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Zero is a really low number. You should be able to develop SOME pressure by turning the motor over by hand. You should hear some hissing and puffing as the exhaust valve opens, even at a few RPM.
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CC: NSA All things are burning, know this and be released. 82 Benz 240 D, Kuan Yin 12 Ford Escape 4wd You're four times It's hard to more likely to concentrate on have an accident two things when you're on at the same time. a cell phone. www.kiva.org It's not like there's anything wrong with feeling good, is there? |
#22
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Set the harmonic balancer to zero with the cam marks lined up. Remember to concentrate on the cam marks. Then look at the harmonic balancer. Your number one cylinder is then at top dead center. Inject some air into the number one cylinder. You will hear where it is leaving the engine.
I am going to take a wild guess. When you set your valves. You did leave a gap between the valve and the rocker arm? This is not a hydralic system. where there is a preload on the lifter. Whenever I got a head back from a machine shop I inverted it on a bench and added some very light oil around the valves. I expected it to still be there hours later. Or the valves where not tight. I expect what you find with the number one cylinder will be consistent with the other cylinders. |
#23
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Nobody watched the clip the OP posted way back in Post #5? The engine clearly has no compression.
__________________
Current stable: 1995 E320 157K (Nancy) 1983 500SL 125K (SLoL) Gone but not forgotten: 1986 300SDL (RIP) 1991 350SD 1991 560SEL 1990 560SEL 1986 500SEL Euro (Rusted to nothing at 47K!) Gone and wanting to forget: 1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz] |
#24
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Loosen rockers so that the valves are closed, then roll it and see if you have compression.
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#25
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Quote:
5 cylinders that have no compression when you can hear the compression when the engine is turning? I'm thinking he used 3 defective, broken, or incorrectly installed testers. The needle doesn't move at all. You can hear the compression when he cranks it.
__________________
Milan Brown 1979 240D, rebuilt OM617.952 turbo diesel, rebuilt 722.315 transmission - engine spun a rod bearing 1979 300SD, ~90k original miles, all stock |
#26
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Quote:
__________________
Current stable: 1995 E320 157K (Nancy) 1983 500SL 125K (SLoL) Gone but not forgotten: 1986 300SDL (RIP) 1991 350SD 1991 560SEL 1990 560SEL 1986 500SEL Euro (Rusted to nothing at 47K!) Gone and wanting to forget: 1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz] |
#27
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The starter does slow down when it spins over the cylinder with the tester installed.
__________________
Milan Brown 1979 240D, rebuilt OM617.952 turbo diesel, rebuilt 722.315 transmission - engine spun a rod bearing 1979 300SD, ~90k original miles, all stock |
#28
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Barely. With as weak as that starter is, it should have a VERY noticeable change in pitch/cadence. Even on the 140PSI Jeep engines, they have a very distinct tone on each compression stroke. That's clearly missing here on an engine with 2x-3x the compression. Something funky going on.
__________________
Current stable: 1995 E320 157K (Nancy) 1983 500SL 125K (SLoL) Gone but not forgotten: 1986 300SDL (RIP) 1991 350SD 1991 560SEL 1990 560SEL 1986 500SEL Euro (Rusted to nothing at 47K!) Gone and wanting to forget: 1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz] |
#29
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Hah I feel stupid, had I watched the video I'd have seen everything was rotating.
__________________
617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap |
#30
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Place shop towels over the injector holes when you crank it. You should be hearing a "puff" and the towel should move when you crank it if it has any compression at all.
Without knowing what exactly you are considering a "rebuild" people are just shooting in the dark.
__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.” ― Brian P. Cleary, You Oughta Know By Now |
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