I have #1 420 psi
#2 435
#3 400
#4 380
#5 455
#6 380


Not the best, fair.

I glowed 3 times and it started up normally.

__________________
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.

If only mine started as smoothly...




That's a big undertaking for me. I would do it, but i'll hold off.

__________________
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.

Not really a "smooth" start, had he glowed a bit longer it probably wouldn't have chugged and coughed as much. With the early style glow plug relay, you don't get afterglow, so on cold days it's a good idea to glow longer once the light goes out.

My SDL needed new valve guides. The original were cast iron and had worn a good amount of slop in them. The replacement are phosphor bronze and should last longer. Don't bother refurbing a head until you know it's crack-free, warp-free and worth rebuilding. If it's cracked, warped, eroded, or just worn out, consider a #17 or later head.

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

You sure about that? I don't think these engines had 455PSI brand new... Much less at 300K+

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

the peak psi on a new engine is 418psi according to the service manual IIRC.

Giants, I don't think you're doing the compression test correctly. you have to hold the pedal WOT for two compression hits or 5 seconds and quit. that's why you're seeing such high cylinder pressures.

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Only diesels in this driveway.
2005 E320 CDI 243k Black/Black
2008 Chevy 3500HD Duramax 340k
2004 Chevy 2500HD Duramax 220k

a valve job you wouldn't do yourself. you would have to take it to a machine shop. But the removal and install of the head would be your job. which isn't difficult. For a first timer set aside 8 hours if you were to do it.

__________________
Only diesels in this driveway.
2005 E320 CDI 243k Black/Black
2008 Chevy 3500HD Duramax 340k
2004 Chevy 2500HD Duramax 220k

speeling error


It was 435PSI.


I went back and forth between the harbour fright gauge and an older U.S. made gauge and got the same numbers.

__________________
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.

Oh, I didn't know that, that explains everything, i'm prepared for some horrible numbers in the future.

__________________
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.

Why WOT on the throttle? Does that engine have a throttle butterfly like a gasser?

Also, why only two compression strokes? The max it'll reach is the max it'll reach, right?

Not doubting you or busting your chops, just looking to fill a gap in my own knowledge.

I've read about carbon buildup closing off the open area in a head, effectively increasing the compression ratio and increasing PSI on a compression test.

__________________
617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap

New battery?

Sometimes speed of rotation when cranking is what's needed in cold weather starting.....

The maximum rated PSI I've seen quoted is 30bar, which is around 450PSI. That's assuming a NEW engine with perfect valve seating and no cylinder wear. I'd expect a 300K engine to be somewhere in the mid 300's.

WOT means nothing on these diesels, there's no throttle plate. The injectors or glow plugs should be removed, so there's no compression on the untested cylinders either.

As a rule of thumb, the first compression hit should get you somewhere around 50% of your max reading, and you should have the max reading after 3-4 hits. You can crank all you want after that and it should make no difference at all. A low first hit, or a slow buildup to max reading is a sign of low compression, even if the final compression number is acceptable.

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)