I am finally in the later stages of replacing my cylinder head gasket and was told by a friend that i am supose to sand the engine block. Is this true? or do you just clean off all the old gasket and oil and just place the new gasket on?

thanks in advance

1. you have to clean the bolt holes.... most important..
get all water out... i actually use q tips....then i bought a tap of the right
size at autozone 9 buck and it pulled a lot of garbage out...

2. use a razor blade long handle scraper to remove old gasket stuff..

3. then you will need to do something else and this is the debate... some say sand... others say no...

i used fine wet sand paper then cleaned with alchol after wards and mine is working great...

the most difficult part is the stupid timing chain guide on the drivers side... and on my 300e we had to torque and pull 90deg and then another 90 deg and that caused my heart to be in my mouth...

Ideally you want to clean/blow out all the head bolt holes. Lots of Q-tips and carb clean followed by high pressure air. As for the gasket material I soak it a few times a/ carb clean and use a razor blade to get it off. To finish things up I pull the blade (with the blade angeld away from me) to get the last bits of material.

Just in case, you need to have new head bolts when re-installing the head...I've come across a number of people who were unaware of this.

Jonathan

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Blue Ridge Mercedes
Jonathan Hodgman
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Enthusiast Service, Restoration & Tuning.
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Specializing in all pre and post merger AMG's including Hammers and DOHC M117 engines.
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I have the head off and am sanding the block. I have a new question. I am using a 220 grit wet dry paper and there are certain areas (in between the coolant passages) that still have a dark coating on them. most of the block is smooth and has a shiny finish. I am scared to keep sanding the dark areas so they match the metallic areas. how important is the overall finish of the block? a little more sanding has me seeing or feeling slight depressions in the dark areas. I should probably stop sanding now. blue ranger, how even was the finish on your block after sanding down? I have to put this together by tonight so your thoughts will be appreciated. thank you.

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88 300e
92 mr2

my block had all the red stuff gone from my razor scraping...

and my block had silvery spots and dark spots... i wanted it to be pretty but
i figured i had better be careful....

i have done a lot of reading in preperation for this... and it is possible for you not to send your head out... in the old days there was a paste that they would put on the valve and rotate it to seat it into the head... and there are also copper head gaskets... so even if you messed this up you could still get a gasket to sill.... so a lot of what we are doing is over kill.... the books say take a straight edge and lay it corner to corner and look to ensure level... and if its not level or if there is a gap and it gives the measurements something like .005 or something then send for resurfacing.....

i remember when i use to always have my brake rotors turned and ever couple of years i had to buy rotors... and now that i stopped turning them i never seem to buy rotors anymore... its the same thing....i did not have to spend all the money having mine polished, and surfaced, and preasure tested and all that... but i did it anyway....so dont get to freaky about the block... i think the most important thing is the old head gasket stuff and the grit and ensure the bolt holes are clean....

the next time i buy a car needing a head gasket i am going to take a straight edge to it and i am going to do the head myself and put it back together in a day.... and i bet it works just as well...

you are right. the gasket is completely off and there are shiny areas and dark areas. I will just clean it out with acetone and rechase the threads, vacuum and reassemble. luckily I ordered new head studs(parts guy convinced me). its clean enough. cleaner I am sure than if I took it to a local shop for repair. thanks for spraying me with cold water while I was running in circles frantically. I needed that.

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88 300e
92 mr2

i used the old studs and they worked just fine...

but i did buy a nut of the right size and it would not go down the
stud all the way cause of the strech... so the jury is still out on that..


larry said we could use them a second time so i trust his judgement...

now remember when you torq... follow the pattern,,,, go to 54 pds..
and then go 90 deg (1/4 turn) then go another 90 deg (1/4)
the second 90 is heart testing....

so you torq all 16 then 90deg all 16 then 90deg all 16 again...


i let mine idle about 10 or 15 min with the cap off the water.... so there would be no preasure... if i were doing it aqain i would take out the thermostat and leave the air vent bolt open.... i also left the gas cap off... I read all this some where.... then i put the caps back on and went for about a 30 minute drive... right on the interstate.....i came back and there was oil in the water.. but that was my orig problem so i figure it was from the org prob... i flushed and flushed and i think its fine now... although i will check this weekend and let you know...