death via Scotchbrite pads

[levis531]

Is it true that the scotchbrite pads that many people recommend for gasket removal are death to an engine?

www.cadillacforums.com/forums/showthread.php?t=27507

(this topic may have come up B4 but I found no way to search the formums??)

I have just finished taking off my headgasket (80's toyota, bimetal engine, obviously) using a (red) scotchbrite abrasive pad on the drill (I am re-building the head)

3. Questions.

1. After the rebuild, to get these "40 micron particles" out of my system why can't I just change the oil and filter (or even use an oil/turpentine mix as a cleaner) a few times over the first few 100 miles (keeping low revs, temps etc)

2. What can I do before re-fitting the head to get these "40 micron particles" out of my system. The block is still on the car (I'm doing just head rebuild). I pretty well stuffed rags in all the coolant and oil holes/chambers in the block. Can't I just use a "oil cloth" or something to wipe the scotchbrite residue off. On the head, can I just clean the whole thing with compressed air?

3.
Currently, instead of the head mating surface shining brightly there are tiny swirling scratches left behind by the abrasive rotating pad. Is this serious?

thanks for all the help

David

[boosted ls1]

You could contact a few oil filter companies and see if their filters will catch smaller particles.

Boosted.

[lanciachris]

Note that they dont actually present any form of proof on that thread.

[nel]

Have never used scotchbrite when doing a head job personally, but in any case always try to clean up well before before putting in clean charges of oil/filter and coolant and running the engine. This includes:

- putting a bit of oil around the piston rings, then moving the pistons up and down wiping the bores repeatedly with kitchen roll until it's coming up spotless.
- drain the oil then rinse down the oil drain galleries with white spirits followed by clean engine oil, all the time keeping the sump plug out so that it keeps draining through. I HOPE that the upcoming oil feed drilling was kept well plugged, as this one is post-filter - a bit more delicate if you've put abrasive grit down this as it'll go straight to the cam bearings on start up!

The head should be easy to clean given that it's on the bench - compressed air, white spirits, etc.

The "scratched" surface post clean up should be OK, as long as it's absolutely flat and not scored. The gasket coating should accommodate the swirls and key into them. Any doubts or an uncoated gasket I'd use a thin layer of blue hylomar, but the rcommendations vary from engine to engine. BTW - I discovered recently the this product is carcinogenic so careful with it - when I was a keen student I used lots of it without being aware..

Best of luck

[levis531]

People

I appreciate your inputs...

boosted ls1:
Good call! I looked at a few under google
e.g.
http://minimopar.knizefamily.net/oilfilterstudy.html

although is written for US market, it talks sensibly about SAE (Society of Automotive Engineers) standard tests. Apparently 97% success for filtering 40 micron sized particles for paper filters.
Its quite interesting to read about some of the shoddy design (return flow of dirty oil and bits of paper! and glue! from Fram, for example)

lanciachris:
I agree that no form of proof is a little fishy, especially now that I read that 40 microns is standard partcile size for any oil filter. But time will tell.


nel:
very much appreciate the input (especially putting my mind to rest re: the light scratches. At this point I don't know which is the flow and which is the upcoming oil feed drilling but I guess a closer look at the Haynes man. will show me. But a very, very good point about this going straight to the cam bearings!

cheers

David

[nighthawk]

The oil galery up to the head will be a small bore drilling, if you look at the new head gasket, it usually has a little more of the sealant material round it.

the oil return to the sump will look not to disimilar to the water jackets.