'77 Luhrs 28 ft. diesel repower SPLASHED!

[CIVPAC6]

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

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

Ahoy Bert!
Concerning the 6.2L:

An outfit called "Covington" was marinizing them in the '80's.

I had a 1986 version in a Tollycraft 26' for about 10 years ... it worked fine.

When I bought the boat in 1997, I called Covington and talked with one of the "old dudes" and got some info on the "marinization":

The word was that it was an "out of the box" truck version of the engine ... the Higher Horsepower "J-Code" model. If I remember right, the engine serial number will end in a "J". (The "C-Code" versions were lower HP.) Obviously marine Manifolds, Raw water pump, Heat Exchanger etc were added.

As you seem to know, both OSCO and Barr have made Manifolds for the 6.2L engine, MARINEMANIFOLD.COM still lists the OSCO under "Conversion Manifolds: Diesel engines"

Your earlier comment about the manual glow plug controller sounds good. Mine had a controller that would cycle the plugs on until the engine was warm, unfortunately the system sometimes held them on too long and the plugs failed prematurely.

It sounds like you know what you are doing .... I just wanted to confirm that the professionals have done EXACTLY the same thing with the 6.2 (J), and at least for me, it worked well.

FYI, mine had a "Twin Disc 502" (bulletproof) marine gear, but I recall that the Velvet Drive was also offered.

Good Luck!
Sam

 

[QC]

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

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

Sam,

Do you have any more performance data? Top speed, WOT RPM, gear ratio, and propeller specs would help with predicting Bert's performance.

 

[Luhrs28]

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

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

Sam: Thanks for the good input. Yes mine's a J-code engine.

Another company that was doing a lot of marinization (marinating?) with GM 6.2's is Peninsular. They're still in business but now they use the 6.5 turbo.

A lot of people are real negative about using a truck engine, but my viewpoint is still that it's a big advantage that I can buy about 5 complete GM engines for the price of 1 Yanmar. Plus I can get parts for it just about anywhere. You can't beat mass production. Yanmars are probably hand-assembled one at a time.

 

[QC]

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

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

Don't worry about the truck negativity, that is probably from those who think you're using unsafe ignition and electrical stuff and somehow think truck engines are not suitable for a marine application. They are failing to understand that those regs are primarily gasoline driven and that steady state (marine use) is easy with a truck fuel map. Truck engines are driven under much more severe load and speed changes than any marine engine ever is. The exception being the heavy steady state load of marine which I will get back to . . .

The only other real difference would be that a truck fuel map may be less fuel efficient than it's marine counterpart (if there was one). Generally speaking a truck engine will run with more retarded ignition timing for lower on-highway NOx requirements.

Now to the load factor thing . . . a naturally aspirated diesel is not going to be hard worked no matter how you use it. They just aren't stressed. Without excess air (turbo) there is no real way to get cylinder pressures up to the point of an issue. She'll blow billowing black smoke if you try and "turn the wick up" and you will stop doing it. As long as you keep it cool, and don't blow any injector tips which might lead to one cylinder being seriously overfueld and then washed down, I don't think you can hurt it . . .

 

[proshadetree]

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

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

I put a 96 GMC truck engine in my Bayliner It is a 305. If that is how automotive style engines run in boats I am going to auto retrofit my century Might just get 40MPH out of her Killer project dude

 

[CIVPAC6]

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

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

RE: Propeller spec's etc on a similar installation (see posts #121 and 122)

Sadly, my notes went with the boat when I sold it (dumb move), but "from memory":

Boat: Tollycraft 26 1973, straight shaft version, Length 26'8", Beam 10', Disp 10,000lbs
Engine: "GM" 6.2L J-code (180HP...Berts should be the same)
Trans: 1.51/1 reduction Twin Disc
Props:
The previous owner had a 16x13 non cupped screw. He said it was "not enough".
I replaced the prop with a 16x15. This may have been a bit "too much" as I was never able to quite get the proper WOT RPM after that.

With the 16x15 (and 1.51/1 reduction):
Max speed was about 14.5kts at about 3200 Engine RPM.
"Cruise" was 10kts at 2500 +/-

 

[Luhrs28]

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

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

CIVPAC thanks very much for that information. That's the first real-world data I've been given regarding the prop, and it makes sense. I'd been thinking I need a little less prop than the 16 X 17 that was in use with the original Chrysler 360 gasser. I'd rather start out a little underpropped than over.

I have to study up on cupped vs. non-cupped. I have no idea what that means.

Thanks again for the data from your 6.2 diesel boat. It's very encouraging to find out that my top speed should be more than 7 knots.

Bert

 

[proshadetree]

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

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

Luhrs Is this boat going to be a slip boat? Do you have a way to pull it if need be? If you can get it out of the water I would stay with what I have until rpm is known. Now I need updates and pics

 

[Luhrs28]

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

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

Proshadetree:

1) I have to change the prop anyway because it's R.H. and I need a L.H. (my original transmission was shot. It couldn't be rebuilt and the only one I could find in decent shape is a port tranny out of a twin-engine boat, which rotates CCW when standing at the transom looking at the prop)

2) I can usually only get over to the boatyard on weekends, so sorry no new pics until Sat/Sunday.

And yes it's going to be kept in a slip. The marina has a standard fee for hauling it up for 1 hour to change props. I don't think it's too expensive.

Thanks!

 

[proshadetree]

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

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

No pics If you have to buy one have you looked for used? Might be cheaper if you make the wrong choice. I have changed a few outdrive props in the water but I dont think I would do yours.

 

[Luhrs28]

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

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

Since you guys have been very helpful with the comments and info lately I've decided to reward you with some new photos.

There comes a time in any project when you must let the credit card fly and just figure you'll pay it off later. Much later in some cases. I've been buying all sorts of stuff so I can keep making progress.

Here are the Racor fuel filters I just got. Why 2? The optimum setup for a diesel is to have a 30-micron pre-filter between the tank and fuel pump, and a 2-micron between the fuel pump and injection pump. These Racors are real nice. Each one is also a water separator (the clear bowl on the bottom) which you can drain, and they have a built-in hand primer pump.

I also bought a dual remote oil filter kit, made by Trans-Dapt. I'm going to use different hoses than what came in the kit but otherwise it should work out nice. And yes before the purists blast me it's an automotive part, not marine. Does it matter?

Here are some electrical parts to help straighten out the rat's nest of wiring:

3-way fuel valves. Why 2? Because with a diesel you have to have a return line to the tank, and you should return the fuel to the same tank you're drawing it from.

Here are a couple of homemade parts. Remember back in Episode 11 (I'm making that up) I told you my boat originally had no fuel gauges, only some kind of mechanical float gizmo with a dial on top of each tank. With these 1.5" pipe adapters I can now use any standard $24 float sending unit.

Well that's about it. I plan to head over to the boatyard to do some electrical work but it's 29 degrees right now in New Jersey and the high is only going up to about 42. Ugh! But I'm sure some of you live in colder places than NJ so I should shut up and get to work.

Bert

 

[hinric1]

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

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

Whats your plan with the engine wiring?
If you've got a schematic your working with? could you post it?

I've got x2 6.5's that have been extremely badly wired, I'm thinking of starting again from scratch... and making a new dash like yours

loving the thread

 

[Luhrs28]

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

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

Hinric: I haven't made a schematic but I can describe what I'm doing. But I think the 6.5 might have a couple more devices than the 6.2.

- Ground: #2 AWG cable to the block

- Starter motor: #2 AWG cable to the big post on the starter solenoid. The little (coil) post will be wired to a momentary pushbutton at the helm, getting battery + from my + bus bar. A #14 wire can be used for the coil. On the way from the switch to the starter coil it should be wired through the neutral safety switch in the transmission, if your boat has one.

- Glow plugs: I'm going to have the standard GM glow-plug solenoid (looks like a Ford starter solenoid) mounted to a bulkhead. I'll have a fairly big wire (#8 AWG?) going from the battery + to the solenoid post that's powered all the time. Also a #8 AWG from the switched post to all 8 glow plugs. Then to energize the solenoid I'll have a #14 wire from battery + thru a momentary pushbutton at the helm (with red pilot light), then down to the solenoid coil terminal. In summer temps a 4-5 second glow should be enough to get it started.

- Fuel shutoff solenoid on injection pump (usually pink wire in a truck): I'm going to have this go to a key switch so it acts just like the ignition switch in a car. I also have a pilot light to show that it's energized.

- Cold advance solenoid on injection pump: In a truck this is wired through a temperature switch in one of the cyl. heads, but I'm going to make mine simpler. I'm just wiring it to a rocker switch with a pilot light. It should only have to be on for the first minute or so of running.

- Fast idle solenoid on injection pump throttle linkage: Same as the cold advance, wired to a rocker switch with a pilot light. After a minute or so after being started cold it can be shut off, as most diesels don't tend to stall after running for a minute.

- I also have a Teleflex tach pickup I'm mounting in the bellhousing. You just have to drill and tap a 3/4"-16 hole for it, aligned with the flywheel teeth. If you don't want to do it this way you can also get a tach signal out of the alternator, but it has to be a certain type of alternator. My alt is a 1-wire so it doesn't have that signal output.

I believe that's everything on my engine.

 

[archbuilder]

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

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

I have to say this is a interesting thread...I love learning about the ins and outs of a diesel in a boat. Nice work, keep us posted!

 

[sqbtr]

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

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

I just picked up a '69 Ulrichsen allure 25 flybridge. It needs a repower.

Can't wait to see your finished project

 

[Luhrs28]

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

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

I'll be doing some more stuff down at the boatyard tomorrow. Although I have to check the weather. I think Sunday is going to be nasty freezing rain.

I envy you guys with a 14-footer in a heated garage.

 

[archbuilder]

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

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

Build a tent

 

[Triton II]

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

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

Build a tent

With a BIG arch!

TII

 

[Luhrs28]

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

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

Here's what I was doing today: wiring

I know the picture doesn't tell you much (aside from the fact that I make a big mess when I'm working), but I actually got a lot done today. I now have about 95% of the wiring straightened out and everything working as it should.

The previous owner liked to use lamp cord, believe it or not. He(or she?) also paid no attention to the wire gauge being sized for the amps. So I ripped it all out and ran new wire in flexible liquid-tight conduits under the cabin.

Here's a question for you guys: Do any of you periodically spray all your terminal connections at busbars with some anti-corrosion stuff? I'm thinking that would be a good idea. At work we have spray cosmoline which I think would be good for wiring terminations. What do you think about that?

 

[sprintst]

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

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

I was going to do my electrical bus connectors with dielectric greae internally and any exposed screws connectors, etc with liquid electrical tape.