In the past I have gotten around this limitation by using a "gun drill". A gun drill will run more true than a twist drill and is used for high depth to diameter ratios. These bolts are five inches long, and hardened according to one DD source. So was thinking better safe than sorry.
More on the fascinating gun drill can be learned here: https://en.m.wikipedia.org/wiki/Gun_drill
and here: http://www.unisig.com/information-an...-gun-drilling/
The worst part is that you have no idea the twist drill has wandered until it pops out somewhere. It might run true, but my luck has more often resulted in it going way off center.
I have been trying to by a used one for some time but all these magnetic drills hold their value very well and a classic like bux has almost a cult following. You have to keep an eye out for them and move fast when a good one is up for sale and be prepared to pay top dollar.
Ah yes, but it's a long drive from Sydney to Southern California, eh Shaun? Might be a tad more than $80 AUS for that job!Most of the time is in driving and setup.
One more try with the hole saw idea. It is obviously a good idea on account of I thought of it. At least as good as drinking the booze before peeing on the engine. I found a thinner wall and smaller diameter (well, it looks thin in the picture). If you can drill through the mess between the bolt and the housing without removing too much housing, you might be able to guide the drill bit if still needed without really tearing up the hole.
Now if you could just sneak a gun drill down the center of the diamond drill... What, go find a stiff drink and stop typing at you? Oh. OK. well, right. Bye.
Management is the art of counting beans. Leadership is the art of making every being count. --Joe Finch
So I went up to the boat this last weekend and took to this bolt. I tried the Alum and it was doing something but was too slow for the limited time I had, and I didn't feel comfortable just leaving it to work while not being there for the week. Same with the acid.
I applied a lot of heat but the blower is a huge heat sink and I am not sure if much of it got to the bolt.
One thing that occured to me is that the bolt might protrude into the air box. I have to pull the cylinder liners to free some stuck pistons and when I do that I should be able to get a torch into the air box from the non-blower side and heat the bolt directly on its "back side" aka the threaded end. This may also be the best place to drill it out from since the threads are right there, not five inches away.
The only catch is that I would have to drop the oil pan and unbolt the connecting rods from below. I think there is room to do that. What there may not be room for is a few hammer blows to the rods in order to get the rod, piston, and liner to move up, and out of the block. Perhaps a crow bar through the inspection holes to the air box could be used to "motivate" the liners out??
Am I being overly concerned about having to cut a hole in the cabin roof to get the engines out? Is it no big deal? The roof is fiberglass over plywood. It is arch shaped, but I don't see any ribs so I have no idea how they got that arch shape into it. My main fear is the cutout will spring flat and that I'll then have a heck of a time getting it back in and arched correctly.
My weakness in this adventure is woodworking. That's why i tend to be conservative about that aspect of repair. I guess a wooden boat may not have been the best option for me LOL
Hmmm. Yeah, that does change things a bit. Sorry Leo. I'm all out of suggestions now. I think you gotta go ahead with the plan you are comfortable with.
I wish there were more old timer shipwrights around. I would gladly pay them to come and explain to me how that plywood was arched with no ribs. Mind you it's from 1948 so I don't think it's laminated but there must be a way to find out what happens if you cut a hole in it.
For the love of God, why do people do these things? Why would you let the boat sink in the first place. And when you raised it would it have been that hard to pickle the engines? I have never seen shoddy workmanship as that I have seen in boats. What is it about boats that causes people to do their worst work? It's not just my boat - a lot of boats I looked at buying had been real nice until about 10-15 years into their life. At that point the workmanship goes way down to the point of being dangerous. Gas fired home water heaters!!! speaker wire with 115V on it???? stuck open through hulls with wooden plugs driven in AS A PERMANENT FIX?
I noticed you also have a 4-53 engine your boat. Are you happy with it (i have never heard one run) and does it make much noise?
The blower is seized,isn't it?
How much is good /rebuilt one?
I'd be tempted to put the sawzall through it and get at the bolts from the clean dry side,instead of pissing with the wet dirty innards.
R(who hasn't touched a Detroit since the mid 80s
Last edited by Ron Williamson; 02-15-2017 at 08:35 PM.
Sleep with one eye open.
A reman blower is $500-$1000 on eBay so not something you want to casually cut up, but I agree - not out of the question. Certainly might be worth doing that before a full in-frame rebuild on a motor that doesn't necessarily need one.
Leo, I have a 3-53 in Petrel. Pretty similar to your 4-53s though. It's very noisy but I do like it a lot. My loyalty to the DD was secured when it started right up after sitting for over a year - and that after being half-submerged for who knows how long. And I have high hopes of taming the noise with better soundproofing. With the size of the engine room you must have, given that your boat was originally powered with 671s, I have to think you can get enough sound barrier in there so noise won't be a problem. And I assume your motors are wet exhaust, which will help. I have a friend with twin 4-71s in a boat of similar size to yours and I think they are plenty quiet enough.
Yes, the blower is seized but most places said they would accept it as a core so long as the case and rotors do not look overly pitted. My plan was to rebuild the blower, and if too much Alu is missing from the rotors and case I would send them out for and extra thick anodizing.
Yes the engine room is fairly big and the 3-53's look pretty diminutive in there. There should be plenty of room for sound insulation.
Half submerged does explain all the rust. As I recall you also had a pair of 6-71's in your speed boat and them as well right?
At my wife's request I did a lot of work trying to quiet down the 6-71's before I decided to try and make these 4-53's run so if your interested in that let me know and I'll put together a quick thread. I have assumed the same things that worked on the the 6-71's will work on the 4-53's and a 3-53.
Yes the blower is seized and the core. However it's still good as a core and the core charge on them is around $450 around these parts.
If I didn't have to pull liners and pistons I agree with you, It would be saw time. But since I do I was thinking that coming in from the air box might allow me to save the blower.
Thanks Leo. I think I went down the same road. My list of links probably looks a lot like yours Although I also have a ton of stuff on dry stack setups as well since that's what I have on Petrel. And if you haven't signed up for a membership on boatdiesel.com yet then I HIGHLY recommend that site. Membership is not free, but it's cheap and the site is a tremendous source of info. In fact, not sure why I didn't think of this before, but that would be a great place to look for advice on getting the blower off.At my wife's request I did a lot of work trying to quiet down the 6-71's before I decided to try and make these 4-53's run so if your interested in that let me know and I'll put together a quick thread. I have assumed the same things that worked on the the 6-71's will work on the 4-53's and a 3-53.
Re: intake noise. Yes, definitely on my list. Tentative plan is to build a baffled duct for the intake but I'm going to deal with everything else first and see how bad it is.
She sure is cute. Reminds me of the little TUG that could. I like work boats for the same reasons I like old Dodge power wagons. Form following function is visually stimulating. Maybe because you see so little of that these days.