'77 Luhrs 28 ft. diesel repower SPLASHED!

[Luhrs28]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Yes the weather has been nice and warm still, so I'm trying to keep forging ahead with anything involving adhesives or coatings.

Yesterday I finally got my thru-hulls/seacocks permanently installed with 5200. I used backing plates of 1/2" thick fiberglass instead of wood. I think that 1/2" fiberglass plate would stop a round from a .44 Magnum. It took quite awhile to get through them with a hole saw.

I'm also going to fair in all around the outer pickup with epoxy.

I sanded, stained and put 3 coats of clear spar urethane on the "dashboard" inside the cabin:

Gettin' ready to install the waste tank for the head:

When I bought the boat it had an electrical treatment unit and no connection to pump it out. It only had a hose going to a thru-hull in the bottom with a valve. Maybe that was legal in 1977 but it sure isn't now so I'm setting it up so the only way the tank can be emptied is to pump it out. That should make the Coast Guard happy if they stop me for an inspection.

I'm going to head over to the boatyard and see what I can do today. One thing I've been putting off is messing with the twin 65-gal fuel tanks. I was trying to just leave them in place but I might have to yank them to add a return line fitting. (the diesel injection system has to be able to return fuel to the tank)

 

[sasto]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Hi Mr. Luhrs...The holding tank you removed may be an approved Marine Sanitation Device. Send it my way! While your at it I would recommend another fitting on your tank with a plug. I have used one to pump out any water or growth from the bottom of the tank. Your project looks great and enjoy seeing you put her back to "better than new". Great going!

 

[Blue Crabber]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Well, looking good! Keep up the good work. Looking forward to todays update

 

[Luhrs28]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Hi Blue Crabber and other interested waterheads. Sorry to disappoint you but I didn't get much done on the boat today. I was only there about an hour when my daughter called and wanted to ride bikes. So I threw down my tools and headed home.

I'm about to order some more parts from iboats right now, so I have some stuff to install next weekend.

Thanks again for the encouraging messages.

Bert

 

[coastalcruiser]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

just subscribed to this thread.
Nice work so far!
keep up the good work.

 

[Luhrs28]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

I've found AutoCAD is very useful for a project like this. I use it at work (I design industrial machines), so I made a complete model of my project:

The space between the prop shaft flange and V-drive output flange is for a flex coupling I plan to install.

What's interesting is that the prop shaft is on a 15 degree angle but the V-drive is 20 degrees. That sits the engine on a 5 degree angle. I think that must've been intentional on the part of Paragon (the transmission manufacturer), to replicate how a V8 normally sits in a car or truck. That angle helps the oil return to the deepest part of the pan, so you don't get oil pickup starvation when the "vehicle" leans at an angle in any plane.

You can see I'm really tight on space for the air cleaner under the hatch. I think I might have to go with a K&N kit that ducts the air into the engine and has a big cone air filter that sits alongside the engine.

Other than that it looks like it's going to fit like a glove.

 

[sasto]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

We have gone as far as 11 degrees on a diesel on boats of simular size with straight drive. 15 degree shaft angle seems high.....I'm not an engineer...just a builder following directions....Good luck..

 

[Luhrs28]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Sasto: Thanks for the info on the permissable engine angle.

I have no idea what angle most inboard prop-shafts are set at. All I know is the one in my boat is at 15 degrees. It seems like if it were less than that the top of the propeller would be too close to the hull. Also heck its worked for this boat since 1977 so I'm sure not changing it.

 

[sasto]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Sasto: Thanks for the info on the permissable engine angle.

I have no idea what angle most inboard prop-shafts are set at. All I know is the one in my boat is at 15 degrees. It seems like if it were less than that the top of the propeller would be too close to the hull. Also heck its worked for this boat since 1977 so I'm sure not changing it.

Good......the engineers at Luhrs know more about your boat than me... Great job your doing!

 

[Blue Crabber]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Good......the engineers at Luhrs know more about your boat than me... Great job your doing!

I second that and always look forward to your updates!

 

[Luhrs28]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Thanks guys! The weather looks pretty good for this weekend so I plan to be messin' around with a couple of things on my boat. I'll post some new pics to show what I'm up to.

Thanks again for the interest in my project.

 

[Tiwaz]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Looking great so far, love seeing another big boat project.

 

[zach103]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Thanks guys! The weather looks pretty good for this weekend so I plan to be messin' around with a couple of things on my boat. I'll post some new pics to show what I'm up to.

Thanks again for the interest in my project.

Love the work so far. its cold here so now my project is slowing down im glad the weathers still good for you

 

[scipper77]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

You can see I'm really tight on space for the air cleaner under the hatch. I think I might have to go with a K&N kit that ducts the air into the engine and has a big cone air filter that sits alongside the engine.

Other than that it looks like it's going to fit like a glove.

If this diesel marine is anything like the gas engine in my little open bow you don't really need an air filter, just a flame arrester. There isn't any dust on the water. Of course I know nothing about diesel fuel systems so feel free to disregard this post if I am off base.

 

[Luhrs28]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

I had to finally come to grips with the fuel tanks this weekend. Believe it or not my boat had no fuel gauge at the control station. All it had was a mechanical float gauge on top of each tank. So to see how much fuel was on board you had to come down from the flybridge, open the engine hatch and stick your head under there and look with a flashlight:

Well I decided that sux. I want to put sending units in so I can have real gauges up on the flybridge. But as you can see in the photo there's no way to get the sending unit in without removing the fuel tanks. And to remove each tank would require cutting out a partial fiberglass bulkhead.

So I took a shortcut:

8" hatch kit:

Finished:

I know you purists are going to say I should've removed the tanks instead of cutting into my deck, but I just couldn't see spending an extra 20 hours on that. Plus this way if I have a problem with a sending unit at any time in the future I can have it out in 5 minutes.

I did some other shiznitz which I'll show you in the following post.

 

[Luhrs28]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Also I found out from my CAD drawing that the motor mounts were going to hang off the outer edge of the main stringers by 3/4". So I decided to add a 2" x 4" alongside each stringer. I wasn't real sure what the textbook method is for this so I came up with my own. I just put an epoxied layer of biax between the original stringer and the 2" x 4" and clamped it.

The holes in the 2" x 4" are to fit around bolts sticking out from the original main stringers.

To distribute the weight of the engine over more of the stringers, instead of just bolting the engine mounts down to the wood I'm going to use a piece of steel 3" x 4" X 1/4" wall angle about 16" long on each side.

 

[fat fanny]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Luhrs been following your thread from the start I like the hatch idea easy breezy and functional. Watching to see the next step you seem to be working @ no scheduled pace which makes planning more comfortable and the results look good to me.

 

[Luhrs28]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Back to my transmission. I got a rebuilt one that I think is good from a local guy, but I want to test it first. So I made this handy drill-driver tool:

I just cut the center hub out of an old drive damper and welded it to a 1/2" dia. shank I made on the lathe at work. (don't look too close at my welding job........it's awful but for this it's good enough)

So I can drive my tranny with a 1/2" drill just like the engine will:

By the way, if anyone is interested in how the bi-directional Paragon and Velvet Drive hydraulic inboard tranny's work, I'll give you a little explanation. (photos below from my 2nd junk Paragon)

Both Paragon and Velvet drive use a very clever design that allows the tranny to be configured in the field for the engine rotation direction being used. This is done simply by repositioning the input flange by 180 degrees.

Here's the gear pump inside the front flange:

The fluid gets drawn into one of the sort of pie-shaped open areas of the gears, travels around the stator piece that's shaped like a moon crescent, and is forced out the other pie-shaped open area. This gear pump mates up with channels cast into the backside of the front flange:

Which mates up with the fluid pickup hole at the 6 o'clock position in the housing, and the pressure output port at the 9:30 o'clock position:

I'm really impressed with how ingenious this design is. If you have a RIGHT rotating engine you assemble the front flange/pump onto the case one way. If you have a LEFT rotating engine you assemble it shifted 180 degrees. That's all you have to do to make it work with any engine. That's a huge advantage for marine shops.

I read on the 'Net that these transmissions were designed in the early 1950's.

 

[coastalcruiser]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

my dad has an older 57' chris craft
he checks fuel with a long stick so i would believe it

 

[Blue Crabber]

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Re: '77 Luhrs 28 ft. diesel repower - just beginning

Looking great. Can't blame you for putting in the 8" hatch. I would have done the same thing most likely. I have got 2 in my boat, 1 at the fuel hose connections and 1 at the sending unit. (But it is just a small little bowrider compared to yours )

Keep up the good work!