Hi all,

im working on Head gasket job on my 2004 D2, im a noob, it’s my first one. I bought this D2 with clean carfax and 60k miles, is in pretty good condition. I drove it for around 2000 miles and never overheated but noticed small coolant leak in the front side of the engine right where the block and heads meet, and a valve cover gasket leak so I decided to adventure into a full HG job.

When I pulled the Cylinder heads I noticed that had handwritten marks on them with what seems to be a number 8 in one and number 22 in the other (see pics). Does anyone knows what these numbers mean?

 

maybe the nuber of the head when it was stored on a shelf in a breakers yard

 

It looks as though you might be working on cleaning those heads up yourself. Don't bother.

The general (strong) consensus is that whenever you do a HG job, heads should be professionally worked to insure a perfectly flat mating surface. A valve job is generally part of the job as well. A machine shop will dip them removing all carbon and they will be like new.

 

For both my P38 and D2 I had the heads machined at a shop, but I didn’t have the valves done (both engines only around 150,000 km). If I do another one and have the time, I want to try to resurface it myself. I think I could do as good a job. I don’t regret not having the valves done on these relatively low mileage engines.

 

I'd check the heads out myself before I went them off to a machine shop. Good metal straight edge and a feeler gauge to check the flatness. Pour some gas in each combustion chamber and see if it leaks past the valves to check valve seal.

 

Harv... when you say you would tackle the re-surfacing of your heads, how would you go about that? Do you have access to a milling machine? (Maybe there is a potential cottage industry here for you!)

 

I hand lap heads on a glass table to .001 of an inch. Sandpaper on a leveled surface is as good as any machine shop. I cut 3 angles into the seat by hand with a Neway kit. Have been doing it for 24 years that way. I'm better than any machine shop.

 

As RMT says, a good thick glass plate with sandpaper. I’m interested in how you do the 3 angle valve seats without a machine. Many years ago I worked at a light aircraft engine overhaul shop where we did very good 3 angle grinds, but we had all the equipment. I also have no trouble believing you do a better job than any automotive machine shop.

 

Just like this.

 

Thanks for the video. I’m sure I’ll get set up to do that myself in the next few years.