I'm rebuilding my first engine ever. My 928GT engine seems like a good one to start with. I want to say thanks to Stan for spending a couple of hours on the phone with me the other night. I wrote things down as quickly as I could. I expect I will have a series of relatively unintelligent questions as I get into things further.

Quick update where I am at.
1. Engine is out.
2. Heads rebuilt by Greg Brown.
3. Intake/valve covers/water bridge re-powder coated. (Thanks for the instructions posted on the forum).
4. Oil pan cleaned and burnished.
5. Currently making the parts list to order and scrubbing parts.

Monday is my night to work on the car when I am in town. The progress moves slowly.

Newby question of the night. Should I scrub all of the gasket material off of the head mating surface? I started to with a brillo pad but then became concerned I might scar the surface. Should this surface be perfectly clean? My inclination is to do so but thought I would ask the experts.

Thanks for the help. I would not have taken on this project without this forum.

 

Yes, needs to be scraped off. Go get a pack of 4 to 6" long single edge razor blades, the ones that fit into those plastic scraper handles. Hold it absolutely perpendicular to the block face and scrape all the junk off. Use adjacent deck surfaces to make sure the blade is flat and square on the surface.

 

Perpendicular? I see how that avoids galling the surface but won't the blade be likely to catch and snap?

 

if the blade is held at a 90 angle to the surface being scraped it will neatly remove any debris on the surface and level it .
With the blade at 90 it cant dig into the surface like it would if it was held at 45 degrees

 

Do I need to get the 4-6" blades or will the smaller 1.25" blades I have work. I could see the advantage of a longer blade for holding onto. Are we trying to bridge across a couple of surfaces to keep the blade level?

 

Completely remove the old gasket and make it smooth but do not get gung ho about making it look perfect and shiny. Somtimes it is a fine line between finished and starting to make the surface uneven or scarring the surface.

 

I just use normal razor blades. They work great! Good luck.

 

Yeah, I was thinking about the long blades for 'bridging' but if you're careful the standard single-edge 1.25's are fine.

I need to take a pic of the 12" razor blades we use- in the morgue....

 

Got it. Using a regular razor blade at 90 degrees. I see it is scraping the gasket material off. It looks like there is still some discoloration of the surface but it does not feel like there is any material left on the surface.

Thanks.

 

Use high quality razors, don't buy those cheap ones. The chip ones have a crappy sharp edge that leaves small scratches on the surface. They are so weak that their edge gets damaged easily, once the edge gets damaged, it scratches the surface.

I like these, you can get them at Lows, IRWIN blades,




I also would soak the surface with break cleaner using a tooth brush, and wipe off with a towel, I use microfiber towels sold for car waxing, like the blue, green, yellow ones they sell at wal mart.
Soaking the surface with WD40 may also help in softening the old gasket material. I would try to wipe off as much of the old gasket material off before going at it with a razor.


You don't have to necessarily hold the razor perpendicular. Going perpendicular on a hard old gasket surface will damage the blade and scratch the surface.
After I finish wiping the surface as clean as I can, I soak the surface with break cleaner again and go in an angle, as low as I can. This will remove the high spots. Once you are done doing this then you can go trough it again holding the razor perpendicular.

Make sure you check the blade, every time you scrape it against the surface, for damages. Replace the razor often.

Do not use things like scotchbrite or very fine sand paper.

The surface will never become perfectly clean and all shiny like a freshly machined aluminum surface. You will still see some discolored spots on the surface after your done. Don't go crazy with some kind of abrasive to clean those spots, leave it alone. As long as you don't feel a rough surface with the tip of your finger, your fine.

Make sure both surfaces (block and cylinder head) are perfectly dry of any kind of oil before you put the new gasket on.

 

I thought most coroners used large kitchen knives?

Knife shop I used to visit out in Riverside did the sharpening work and I saw some during one visit.

Seems like the larger razor would be much harder to control. Something like these surgical dissection blades or trimming blades?

 

Close, same-page of the Ted Pella catalog.

Disposable is better for infection control/ good universal precautions practice.

You could do an entire block deck in a few passes. The 12" blades are about $8 a pop.


Sorry, OP, back to your regularly scheduled razor thread.

 

Is that what I'm supposed to do with that thing you brought me? Scrape?

Everytime I take it out to use it for something, it scares me and I put it away.

I can see big chunks of my body coming off, with no pain for several seconds.

 

I thought it might be those, but they looked too creepy. They look super sharp, but so unergonomic, part of me is very curious about how they are used, and a much wiser part of me is very sure I don't want to know.

OTOH I genuinely don't think they would work well as gasket scrapers.

 

They're for 'bread-loafing' organs. And they probably account for more job-related injuries in Pathology than anything else we do. The blades are very high quality Japanese steel, and F'ing sharp. And yes, they'd be a little too flexible for scraping, though maybe not given a stiffer backbone to hold them.

Sorry, now we're really OT.