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OM617 Valve Adjustment Changes as Valve Rotates
Hello Everyone! Thank you all for the great info and help on this site!
I readjusted the valves on my 617 today. I noticed that when the adjusting nuts are jammed and the adjustment is set, if I twist the whole valve assembly (using the adjusting nuts) the adjustment changes slightly. I.e. as I rotate the valve with a feeler gauge inserted, sometimes it is loose, sometimes tight on the feeler gauge. Could this be due to the valve height changing as it rotates on the seat? Is it something to worry about? Also I can hear a squeaking/grinding sound as I rotate the valves on a few cylinders, probably from the valve or spring rotating on the seat or head respectively. Background on the car: 130k miles Recent Work: New injectors, pump timing set, new fuel and air filters, cleaned fuel tank Symptoms: White smoke at startup, some smoke under heavy accel. (not sure what color). Cylinder three is knocking, low on power (hoping it's not low comp.) Thanks! Ben
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http://badges.fuelly.com/images/smallsig-us/353045.png- '80 300D naturally aspirated, 147k
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#2
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Valve and seat are worn oval. I've heard of in situ valve grinds, but I think it's usually done w/ the head off.
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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? |
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One of our Member said that depending on the position of the Valve Rotators the Valve Clearence can be different.
I forget the other detailse He mentioned and I did not save his Thread to My notes. I suppose it is also possible some Valve Rotators are damaged but I have not read any symptoms on that. White smoke is either Coolant or unburned atomized Fuel. You can tell by the smell or if you have evidence of a Head Gasket Leak. Was there any change to the good after the Injectors, Valve adjustment and IP Timing? Or is it the same? You could line up the Camshaft Timing Mark on the back of the Camshaft Gear with the one on the Camshaft Bearing Tower and take a look at the degree marks on the Crankshaft Damper. Alothoug at 130k miles you would not expect that to be off very much.
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84 300D, 82 Volvo 244Gl Diesel |
#4
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Quote:
moon161- does this happen often? Should I do a leak-down test first? Thanks!
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http://badges.fuelly.com/images/smallsig-us/353045.png- '80 300D naturally aspirated, 147k
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#5
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If you take off the head you'll probably find that the valve guides are worn and that amount of wiggle is allowing the valve to float about its seat.
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1992 W201 190E 1.8 171,000 km - Daily driver 1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone 1965 Land Rover Series 2a Station Wagon CIS recovery therapy! 1961 Volvo PV544 Bare metal rat rod-ish thing I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior Don't leave that there - I'll take it to bits! |
#6
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Quote:
DITTO! this is what leads to uneven wear of the valve seats and the valves. As you turn the valve, the thick spots on the valve meet with the high spots on the valve seat due to uneven wear. Adjust the valves at the tightest setting you can find. |
#7
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If all was normal the clearance wouldn't change. I believe these have some sort of device that rotates the valves as the move doesn't it? To promote even wear?
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2004 F150 4.6L -My Daily 2007 Volvo XC70 -Wife's Daily 1998 Ford F150 -Rear ended 1989 J-spec 420SEL -passed onto its new keeper 1982 BMW 733i -fixed and traded for the 420SEL 2003 Volvo V70 5 Speed -scrapped 1997 E290 Turbo Diesel Wagon -traded for above 1992 BMW 525i -traded in 1990 Silver 300TE -hated the M103 1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one 1979 Silver 300D "The Silver Slug" -Sold |
#8
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Quote:
In a perfect world, they should prevent uneven wear. But nothing will stop the wear on the valves and seats which leads to the tighter clearances. The valve rotators (rotocaps) at the bottom of the spring align the spring forces to parallel with the valve stem and are designed to spin so the wear is even. Valve guides wear regardless of this. Over time, it seems that particles settle in the recess where the rotator rests and prevent the balls from rolling freely. Once the valve guides are worn, the rotocaps are less effective. |
#9
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Coolant smells sweetish, fuel smells nasty, is that correct? I have what seems like one cylinder missing a little after a cold start, problem goes away as son as the car warms up. Glow plugs recently done, not losing coolant or anything. Wondering if it is time for new injectors
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#10
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Quote:
Got done adjusting them as you recommended. I also recorded how much the valve height changed as I rotated it: The only valve that was way out of spec was the intake on cylinder 1. Cannot tell a major difference in performance. Cylinder three still knocks. Talked to a Benz mechanic friend who suggested Redline and driving at 70MPH for a while. He said there might be carbon in the cylinders or algae buildup in the IP (the car was sitting for a while). Possibly the valve before the injection line is sticking.
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http://badges.fuelly.com/images/smallsig-us/353045.png- '80 300D naturally aspirated, 147k
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#11
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Quote:
It turned out I timed the Fuel Injection Pump extremely late/retarded. You might try scribing a line arcossed the front Fuel Injection Pump flange and the Engine Block where the Fuel Injection Pump mounts into the Block. That allows you to return the Fuel Injection Pump to where it was origionally. Loosen 3 Nuts on the Front Fuel Injection Pump Flange and the one that is on the rear bottom of the Fuel Injection Pump and rotate the top of the Fuel Injection Pump towards the Block just a bit (and tighten the Flange Nuts); start the Engine and see if that improves your white smoke issue. If it improves the smoke issue then rotate it untill the White Smoke is gone and tighten all the Nuts and see if it drives well like that. If the above does not help rotate the Fuel Injection Pump back and line up your scribed marks to return it to where you started.
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84 300D, 82 Volvo 244Gl Diesel |
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