Gasket Surface Prep

[C-flo]

Hey guys,
I'm getting back to working on my 89 supra again and I'm picking up where I left off a couple of months ago. Last thing I did was pulled the valve covers off because I had oil on some of my spark plugs and for some reason was thinking the valve cover gaskets needed to be changed. After talking with people come to find out it's either a head gasket problem or just the simple fact that my motor has 110,000 miles on it and the valves probably aren't seating right anymore. Anyway, I'm putting the valve covers back on and have started scrapping the sealing surface. Should I just scrap it clean or is there a liquid I can wipe it down with also to ensure all impurities are off of it? I've got one side completely scrapped and it feels nice and smooth but it doesn't have that shine like it would if it had just got milled. It has some shine but there is still a little bit of discoloration. Also I'm noticing some tiny pits in the metal in some areas around the surface and when I scrap it sometimes it leaves some scrap marks in the metal which I'm hoping wont affect the sealing capability of the gasket. Any advice would be much appreciated, and I'm sorry if this post went around the block just to get across the street.

 

[mkiii222]

Valve cover gasket surfaces do not need to be as perfect as head gasket surfaces. You can get away with just using a gasket scraper and making sure they're clean. Slight pitting won't make a difference.

Also, is the oil in the plug galley between the valve covers? This will leak onto the plugs as you pull them out. If so it can be valve cover gaskets or the '3rd valve cover' gasket (14mm hex plugs).

Just get new valve cover gaskets, a tube of FIPG (form in place gasket, used at the front), and 4 of Napa part # 704-1076 (for the 3rd valve cover) and call it a day.

 

[C-flo]

Yeah oil was down in the plug valley on the spark plugs when I pulled them out. 4 out of the 6 had oil on them. Everything is cleaned up and ready to go back together now I'm just having trouble getting that hose next to the oil cap back on the valve cover. I put a little vasoline on the fitting but it isn't wanting to budge. I bought new hex head bolts for the valve covers also instead of having the phillips head cap screws in there. Will this present a problem or does it really matter?

 

[mkiii222]

Just be sure to use the stock 'washers'. The rubber is to allow a small amount of flex so the 'tabs' don't break (learned my lesson the hard way... twice).

And if the oil drain hose is that hard you may want to consider a new one in the near future. # 12263-42010 : ~$30 from Champion/Elmhurst or $40 from a local dealer.

 

[Nghty89]

Just be sure to use the stock 'washers'. The rubber is to allow a small amount of flex so the 'tabs' don't break (learned my lesson the hard way... twice).

And if the oil drain hose is that hard you may want to consider a new one in the near future. # 12263-42010 : ~$30 from Champion/Elmhurst or $40 from a local dealer.

I had one break even with the rubber washer. Shattered the valve cover into several pieces. Must have been something weak in the material, because I did not tighten it much at all. Lol

Sent from my DROIDX using Tapatalk

 

[hvyman]

Razor blade or scrapper and brake cleaner.

 

[mecevans]

If your breaking a valve cover you overtightened it. It needs some give for when the metal heats up and expands.

 

[Nghty89]

The metal was already weak somehow. Trust me, I didn't over tighten it. ; p

Sent from my DROIDX using Tapatalk

 

[hvyman]

Someone over tightened it somewhere down the line for a valve cover to break.

Factory torque spec is 22 inch lbs. Which basically snug is over tightening.

 

[grimreaper]

damn, never seen the valve covers break, I could see the tabs on the outside of the head breaking though. 3 years and 30K just normal washers and bolts= no issues. i didnt even know they had a rubber washer originally! Know I am on the hunt for some..

I have seen the valve covers warped and the head mating surface warped. Pain to get a good seal then as it teeter toters over the middle.

 

[Nghty89]

Yeah, it was definitely a first and a shock for me. I did get them from someone who had abused the head/car pretty badly so I wasn't too terribly surprised. Ill see if I can find some pics or pieces left over...

In retrospect - ill be installing valves covers with the engine OUT of the car... it was a pain cleaning up the shards of aluminum.

Sent from my DROIDX using Tapatalk