What are you thinking Mr Hunter? Do these heads have valve seat inserts? I have been wondering how he went from basically wide open to normal compression during the initial testing.. I cannot see an application of a light oil sealing that valve up that well. Bunker C maybe. Although I am old enough to know that everything is not always logical progression. I even remember opening up some piece of equipment and the defective part had developed a basic face in the failure mode. . Not only that it was just sitting there and smilling at me.

I am expecting:
* Massive carbon on seat and valve.
* Damage on the valve seat and/or face.
* Damaged valve guide canting valve against seat.

Note:
The OM617 INTAKE and EXHAUST valve guide ID specification is 10.000 - 10.015 MM.
I have found many valve guides with 0.75 slop.

Ok. I pulled the head today and there looks to be lots of carbon on the #3 Piston and on the intake valve.

Please look at the photos here.

https://profiles.google.com/u/0/113096178938701157989

https://plus.google.com/u/0/photos/113096178938701157989/albums/5529549010362573505

I can take more photos if you think that would help.

I'd also like to upload the photos to this site so they are stored on the peachparts server.

I now have the following questions:
How bad does this look?

Can I scrape the carbon off the intake valve and piston and put the motor back together?

Do I need to replace the piston and valve?

What should be my next step?

Thanks for all the replies.

Pete

I need this data.

OM617 INTAKE and EXHAUST valve guide ID specification

Was the engine run on WVO? Could this problem have been fixed by dripping some water into the intake while it was running?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I don't think it was run on WVO. I did attempt to mist some water into the intake. Not sure if that helped or hurt. I never did get any compression in the cylinder during a compression test.

whunter,

Do I need to pull the valve guides out in order to measure them? You want me to measure the inside diameter of the stem?

If I have to pull out the valve guide, what tool would I use to do this?

Thanks again.

Pete

Never any compression? I thought you got compression with oil in it?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

kerry,

Sorry, you are correct. When I squirted oil in the injector port, I did get a compression reading over 300 psi. If I waited 30 minuted and did it again, I got no compression.

Do NOT disturb the valve guide !!

Use a telescopic bore gauge to measure the inside diameter of the valve GUIDE 5 mm from the bottom.




Using telescopic bore gauges - The Home Shop Machinist & Machinist's Workshop Magazine's BBS

Repeatability of telescoping gauges for an experienced hand? - Practical Machinist - Largest Manufacturing Technology Forum on the Web

Telescopic Bore Gauge Set - YouTube

whunter,

I will need to track down a small hole bore gauge tomorrow. I'm hoping Advance Auto has them as loaner tools. I can buy them online but I'd rather not wait a week for them to arrive.

After watching the video, the telescopic bore gauge to measure the cylinder bore looks fairly easy to use but measuring the valve guide is definitely going to be more challenging.

Pete

Is there any solvent you would recommend for cleaning the top of the piston and valve? Should I attempts to scrape it off?

The cylinder head and block surface needs to be cleaned in stages:
#1. Mechanic gasket scraper.
#2. Drill mounted wire wheel.
#3. Razor scraper, with a good supply of blades.
#4. Wipe the surfaces with brake or carburetor cleaner, and repeat step #3 and #4 until you are convinced there is no trace of old gasket remaining.
#5. Wipe a light coat of engine oil on the clean surface to prevent rust while you are working, and you are done.


The nasty piston and all valves need to be cleaned = carbon removed, before any reliable answer on condition is possible.

Here are some suggestions for carbon removal chemicals.

removing carbon from pistons - Google Search

removing carbon from pistons - Google Search

chem-dip parts cleaner - Google Search

You have E-mail.

Enjoy.

.

That caked on gunk looks like there has been oil leaking into the combustion chambers - or perhaps this is how an engine looks after running WVO? I don't know...

Here are some pictures of my engine with a busted valve stem that caused a bit of problem!







So OK these picture show a much wetter combustion chamber but I hope they demonstrate my feelings of built up oil shown in your pictures

Attached Thumbnails

     

__________________
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!