Bolts holding on a '78 merc

[silverbullet02]

Gonna be pullin the motor off the boat soon here, and I can only see 4 bolts across the top holding my motor on. It's a '78 merc v6. Don't see any bottom bolts at all. Are they under the trim rams? Kinda confused here. I can't imagine there not being any bottom bolts, but I could be wrong. Thanks for the help. Here is a pic of the 4 bolts I know are there.

Brian

[Raceman]

It's been a long time, but I believe the '78's still had the lower bolts as the through transom route for the power trim. If you look in the bottom of the transom brackets on both sides they'd have hoses through the middle. I KNOW FOR SURE that the '76 & '77 engines were in this configuration and I'm about 99.9% sure the '78's were still that way also. Back then I usta buy a new one every year as soon as the local dealer got one in.

[silverbullet02]

Ok, so where the hydraulic line goes in on each side, there's a bigger looking nut and that is essentially a bolt head and the bolt goes thru to the inside and a nut holding it on there? If so, that makes sense now. The way the head is on the outside, it appears to be locked in by the bracket where it sets in there. That makes sense now. Thanks!

[Raceman]

Yep, that's it in the picture. You'll have to take the nuts off on the inside and tap the bolts out. Only trick is, you can't tap on the ends of the bolts because you'll damage the hydraulic fitting. I think we usta' screw the nuts almost to the end and then use a socket with a bottom in it to tap on it. The earliest ones had stainless nuts too (the hollow bolts are stainless) and there were issues with people running the nuts on and off with impact wrenches and getting em too hot and gauling em, so later Merc changed to brass nuts (not to be confused with the brass balls used for parts pricing:D ). If yours are stainless screw em off slowly, only with hand tools, so they don't get hot and stick. A little lubricant in the threads won't hurt. I always put mine on with some anti-seize and never had a problem. Also, when you go back in with it, the two bolts may be different sizes for different sized hydraulic fittings if I remember right.

The two inner bolts at the top hold the bracket that doubles as the tilt lock, in addition to the hanger for the engine before it's bolted. They don't have to be removed for the engine to come off, but should be loosened some.