Mercruiser 3.0LX valve cover gasket

[dlogvine]

I noticed that the valve cover gasket on 1994 Mercruiser 3.0LX was leaking oil and I bought a replacement rubber gasket on ebay. Put it on the valve cover, used gasket adhesive, tightened up the cover up to spec torque. Took the boat to the lake today and noticed another valve cover leak, similar to the old one but in different location. Tightened up the cover a bit more, leak did not disappear, remained the same or just a little smaller. Did not want to break the bolts, so I took the boat home took of the valve cover and found out the new gasket is in even worse condition than the old one, also split in half where the block was pushing on it, almost chewed up in the other places. It could be because I tried to tighten up the valve cover on the lake, but does not explain an original leak. The gasket is Mercury-Mercruiser Valve cover Gasket 27-806452 it is rubber gasket not cork one. It could have been old and deteriorated a bit, the glue on the bottom was kind of dry and did not stick, but it was in a new sealed bag and ebay seller said it was not this old. Im going to buy a new gasket in the marine store, but it might take a while since they dont have it in stock. The question is, should I buy a rubber or cork gasket (seems like cork would be a better choice, considering the outcomes with two rubber gaskets, original and replacement one. And second question is can I buy an automotive valve cover gasket at the autostore. This will be much faster and I can finish it tonight. And if they are similar, is Mercruiser 3.0 4 cyl engine also using Chevy block, or it is different?
Thank you
Will post the photos of the gaskets in next post.

 

[dlogvine]

[No message]

 

[Bt Doctur]

The 153-cubic-inch (2.5 L) 153 was an inline-four engine which was designed for use in the entry-level Chevy II/Nova. It is a four-cylinder version of the Chevrolet 230 inline-six. Usage of the 153 lasted through 1970 because of low demand (the motor was used as standard equipment with the Kaiser Jeep DJ-5A which was used by the United States Postal Service until 1971 where the 153 was replaced with the AMC inline six after Kaiser Jeep was purchased by American Motors), after which the inline-six was made the base powerplant with the Chevy II/Nova. Currently, descendants of the 153 are used with industrial (forklifts or generators) or marine applications.

 

[dlogvine]

So, I still can't understand if I should use a rubberized cork gasket or there is something wrong with the rubber gaskets that I used? Autozone found the gasket in crossreferense and i can order it from them or try to find one in any of the marine stores

 

[GA_Boater]

When they split like that, it's usually because of over tightening. The gasket sits on an edge on the head that acts as a knife.

Is the valve cover flange flat? You may have to reform it until it is flat and don't crank the bolts down as hard.

 

[dlogvine]

When they split like that, it's usually because of over tightening. The gasket sits on an edge on the head that acts as a knife.

Is the valve cover flange flat? You may have to reform it until it is flat and don't crank the bolts down as hard.

Im an idiot, when I looked at the torque specs, I saw 40 and assumed the torque is 40 ft. lbs, while it is only 40 inch lbs.... Dammit, i feel retarded!!!The cover flange is flat, I'll check it tomorrow and before putting a new gasket.

 

[achris]

40 lb-ft.... I'm surprise you didn't snap the bolts. ...

 

[dlogvine]

40 lb-ft.... I'm surprise you didn't snap the bolts. ...

I am suprized too, but what saved the bolts was a bad torque wrench, it is old and I realized is broken, it stops torking anything at about 25 ft. lbs. But I put a new gasket and tighten it up up to correct specs, the engine runs, no leaks. Also it was a good occasion to change the old oil and filter.

 

[achris]

.... But I put a new gasket and tighten it up up to correct specs, the engine runs, no leaks. ....

Proving that more tight is not necessarily more good.

 

[GA_Boater]

I never misread any instruction and when I do, it's blamed on greasy fingerprints.