Crankcase dowel pins

[Steveng]

I have found out the hard way that the dowel pins that center the main bearings have been pushed down into the block. I can get new ones from a local parts house, but what is the best way to remove the old ones. Do I drill them out, can I heat the surrounding metal and somehow pull them out? Also while reading the manual about the connecting rods, it calls for a special fixture to install the rod caps. Is this just recommended or is it a must.

91 70hp. johnson outboard

 

[oldcatamount]

Re: Crankcase dowel pins

You will need to drill the pins out. I'm actually surprised that they could be pushed down into the block. Are you sure they are pushed down or are they broken off?

 

[JasonAych]

Re: Crankcase dowel pins

Drill down center of pin, thread something in tight, then pull it out?? Haven't had to do that yet but that is what i would think to do.

 

[JasonAych]

Re: Crankcase dowel pins

When I say drill i mean smaller than the dowl so you don't hurt anything.

 

[boobie]

Re: Crankcase dowel pins

If you have an OEM manual they show you how to make a special tool to remove them. They are removed from the cyl side towards the intake manifold. I've always been lazy and didn't make the tool. I just drove the pins out in the correct direction with a "long" punch being careful not to damage the block. I'd rather do this than to try and drill them.

 

[Steveng]

Re: Crankcase dowel pins

Thats what I thought, but do to the luck I have drilling out broken bolts, I decided to take it to the machine shop and have them do it.
Thanks, Steve

 

[Dhadley]

Re: Crankcase dowel pins

Boobie is talking about the pins that locate the front crankcase half. I beleive you are talking about the pins that locate the center main bearings for the crank. If so, they are very easy to remove. Just drill a small ole in them and start a sheet metal screw into one. Now you have something to grab. They'll come out using a pair of pliers. No big deal at all.

 

[boobie]

Re: Crankcase dowel pins

My mistake. Next time I'll read the post a little closer. Sorry.

 

[Dhadley]

Re: Crankcase dowel pins

No problem, you bring up a real good point. We've seen some good blocks ruined because someone did not understand those are tapered pins and need to come out toward the intake.

 

[i57chevy]

do we know how the main bearing dowel was eventually removed and/or pulled out?

 

[Newbie@boats]

do we know how the main bearing dowel was eventually removed and/or pulled out?

No. And since you restarted a post from 10 years ago it’s fixing to get closed.

 

[GA_Boater]

No. And since you restarted a post from 10 years ago it’s fixing to get closed.

Right on!