Manifold Bolts.....

[mapleleaf]

Started pulling my Manifold's today ( one cracked, and valve cover gasket replacement) Got through 14 bolts pretty easily, but have 2 on the port side 2nd cyl. from the back that seem to have had the heads heated to where the allen wrench won't grab. I figured my best option was to drill the heads off, pull the manifold and easyout or something the stud out....
Any gearhead thoughts on this?????

[Supra-in-steamboat]

Possible hack saw, dremmel, file, grind, or etc. a groove in the bolt head that a flat screwdriver would fit in. You could also try a flat screwdriver in the allen head and maybe get lucky with a bite. I have had success with these techniques outside of the marine application. Hope this helps.Good luck.

[purple boat]

I had to cut the heads off mine with a Dremmel and then use a stud extractor. And LOTS of penetrating oil. The flat blade screwdriver probably won't work because in a marine environment the bolt tends to fuse to the manifold and sometimes the head too. I had to PRY my manifold off after cutting the heads off several bolts on one side.

[mapleleaf]

Oh boy...looks like 6 bolts are going to be a problem, and I won't have time to get this done b4 my 2 weeks off at the end of June, Gonna have to live with the valve cover leak a little longer.......

[saltare inverts]

Just order your new 572 and forget about the manifold gasket.

[mapleleaf]

Just order your new 572 and forget about the manifold gasket.

will my boat still float with that in it??? I guess that'd be the end of ballast needs!!

[szarik5]

When I rebuilt my motor I had 4 bolts that were impossible to remove. I tried a stud remover but I ended up drilling the bolts out and using a quality easy out. Problem was with drilling - the bolts over time heat treat themselves and become very hard and the only way I could drill them is to take a masonry bit with a carbide and sharpening that. I bought a special stone for my grinder to sharpen the bit. I also suggest drilling the bolt instead of cutting it off because the allen hole in the bolt will help you with centering the drill.
Takes time but always have been able to eventually take them out. Good luck.

[rludtke]

I purchased a Snap-on set of left-hand drills over 20-some years ago, just for drilling broken bolts. These drills work like a charm. Simply drill the center (in steps- never try to drill to much at once, start small, and lubricate the drill). If the drill doesn't loosen the bolt, then the extractor driven into the hole should. At least the drilling won't have tightened the bolt anymore :o). Use lots of high quality penetrating oil if corrosion is belived to be the culprit.

I have been very succesful in extracting seized and broken bolts using this method.

[mapleleaf]

Thanks guys, at this point I'll have to wait til I'm home after the fourth, it was really a valve cover gasket replacement issue...I was told the starboard side mani is cracked but for the life of me I can't find it, so I'll live with a little smoke have a nice vacation and revisit in July, or the mechanic giving her the once over tomorrow could pull off a miracle and get out the last valve cover bolt that I can't!!! We'll see........