New to me 50, Steel full displacement, engine questions

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
As long as it runs - do not tinker!

Would like to add: reliable, it has to run reliable.
And here we're at the question of preventive maintenance. But which maintenance job is really necessary immediately and which one could wait another year? It depends. But no compromise on reliability - it's a question of safety.

Obie, great looking vessel, congrats!
Regarding your engine:
As long as it runs (reliable) - I wouldn't tinker, regardless the noise. So I'm with RTF.

Might be another story if you're planning a bigger refit project anyway and if you have the money handy.
 
The first step with any 2 stroke Detroit Diesel is ALWAYS an oil change.

The engine requires 40wt CFII spec oil.

Too many folks dont bother to read "da Book" and will dump what is cheap at Wallmart in.

IF you keep it I would be happy to recommend a maint/rebuild DD book to get you up to speed.

BEFORE starting any 2 stroke that may have been out of service for 1/2 a year or more it is imperative that you pull the valve cover First , and be sure all the injectors move with the rack.

Otherwise it may start , scream at high RPM till the fuel or air is shut off.
 
Last edited:
Very good advice thank you. My plan was to do that, have block of wood ready to killl air supply, start and run with garden hose for about 10 minutes then do the oil change. If my memory serves me. The fuel flow through the injectors is like 60 gph, with most all going back to the tank. Would I use a lift pump? Do I have to have a very large filter to handle that volume, even just to fire it off?
Obie
 
I've bench run a bunch of these. I use a outboard motor fuel line with squeeze bulb and a six gal jug. There is a gear pump that pumps fuel into secondary filter, then into fuel supply rail. There is a second return rail that takes fuel back to the tank. Disconnect that and route it back to your jug.

Gear pump is mounted on one end of the blower.

The secondary filter takes care of any filtering you need, provided it is in good shape.

When priming with the squeeze bulb with engine off, you are pushing through the machined clearances in the pump and fuel barely moves through. SLLLLOOOOOW, but do-able.

If you need to prime up the secondary filter, take drain plug off bottom of can and pump fuel in there, bypassing gear pump. Don't start with hose on unless you want a diesel shower.

And definitely make sure injector rails are free to move and have some provision to choke off air. Most old ones came from the factory with a trip type damper, make sure it works and you know how to trip it.
 
Very good advice thank you. My plan was to do that, have block of wood ready to killl air supply, start and run with garden hose for about 10 minutes then do the oil change. If my memory serves me. The fuel flow through the injectors is like 60 gph, with most all going back to the tank. Would I use a lift pump? Do I have to have a very large filter to handle that volume, even just to fire it off?
Obie

I can't ever recommend running with a garden hose.
 
I have a 40hp engine and take off the hose from the seacock and put it into a 5 gal bucket sitting on the trans. Then get a garden hose to maintain the water level in the bucket. Easy to do (flow wise) w a 40hp engine but will probably be able to keep up on a bigger engine. A DD may require a lot of water though.
 
Yes I agree, but DD has a huge metal mas, and it would not work under any load at all, but it should be enough at idle, and of course I will be monitoring the temp, with a gauge and a inferred gauge.
Obie

If anyone thinks this is a horrible idea please chime in. Boat is on the hard, before it gets dropped in I have to know it can run.
 
I think it sounds like fun. As long as you have a bung for the air intake and you are not startled by the noise, which is considerable. We have a Tolly with two 6-71s in our marina and when he goes cruising you can hear him for three days until he rounds the corner by Chatham Point. What could possibly go wrong?
 
Yes I agree, but DD has a huge metal mas, and it would not work under any load at all, but it should be enough at idle, and of course I will be monitoring the temp, with a gauge and a inferred gauge.
Obie

If anyone thinks this is a horrible idea please chime in. Boat is on the hard, before it gets dropped in I have to know it can run.

I already dropped in. I know others will be less conservative than me. Even just for convenience I'd rather have it in a slip so you could keep checking and trying different things and not worry about the hose. I do realize that it's possible all you'd get out of it would be a launch and haul fee.
 
Startled by the noise. I hear that! One time I was working in my engine room on another boat. There was a batterie combiner I was trying to trace out. It had an idiot light hooked to it, so you would know when the solenoid was ingaged. Some how I kicked the motor over and she fired off. Wow did I fly out of there.
 
I had an old (1965) Islander 32 ft sailboat in my back yard that I was reworking. It had a westerbeke in it . I used to crank it up once a week for 7 years . I didn't know any better and I would wedge a garden hose in the thru hull and turn on the faucet . It's a wonder I never hydro locked it .
 
You can run a dd 671 on the hill on a garden hose. At idle and no load, it makes very litttle heat. All you need is a garden hose feeding the sea water pump to lube the impeller and cool the wet exhaust if you have such. You could run it probably a half hour and it will still not get up to temp.

If keel cooled with dry exhaust, you need no garden hose at all.
 
I forgot he is keel cooled .
 
No it's not keel cooled, that is if I ditch the 6-71 and re power. No this setup runs right out the transom. But interesting I did find 3, 3 feet long toobs welded to the inside of the hull. When I trased them out I realized they were origanly the evaporator for the 32 volt refrigeration. Wait I mean condenser, I think?
 
Was your islander 32 a flush deck. I have had 2 of them. The first one I purchased in Port Moody BC. Put a few miles on her. I am probably the only person who ever owned two of them.
 
Do you have dry stack? I had a salt water cooled dry stack and when I left her on the hard for an extended time I removed the impeller and just had someone run the engine until it came up to operating temp. and then shut her down. At one time it was on the hard for a year. Came back put her in the water an went off with no problems. It was a DD 6-53. So with a dry stack you can run the engine for a short time as long as the impeller is out.
 
The 6-71 may pump a high volume of fuel , but its RPM that gets the big volume , I doubt if you will be above idle , not at 2100 RPM.

It is 1000% easier to check the injectors first rather than use an emergency shut down flap as found on motor vehicles or a block of wood.

At higher RPM a forced shut down can suck the oil seals out of the blower , a huge PIA to have replaced.
 
Was your islander 32 a flush deck. I have had 2 of them. The first one I purchased in Port Moody BC. Put a few miles on her. I am probably the only person who ever owned two of them.
No mine was a Wayfarer. It came with an atomic 4 but was upgraded to a diesel.
 
I have a 50 ft marine trader with two sp135's and doo just fine. Bigger is not always better.
 
Here are some numbers for my Krogen 54 in calm water.

LWL 48'
Displ 80,000 lb half load
Engine JD 6068T - 225HP
Transmission 2.93:1
Prop 34x21 (3 blade)

RPM | Speed (kt) | GPH (US)
1000 | 5.0 | 1.2
1200 | 5.8 | 1.8
1400 | 6.8 | 2.5
1600 | 7.6 | 3.4
1800 | 8.3 | 5.7
2000 | 9.0 | 7.3
2200 | 9.4 | 10.7

As you can see the boat can reach hull speed with this setup (not that I'd want to!). I hope this is of use.

Richard
 
That is awesome info Richard, thank you. I do not mind cruising at 7 to 8 kts, as long as my autopilot is working.
 
It's a slick boat - congratulations - and welcome to the steel boat world.

Have you thought about paint, rust prevention, and general hull maintenance? I'm curious what paints for steel boats are used in the PNW area.
 
It's a slick boat - congratulations - and welcome to the steel boat world.

Have you thought about paint, rust prevention, and general hull maintenance? I'm curious what paints for steel boats are used in the PNW area.

I have an aluminum boat now, so this should be a bit different. I plan on putting in a isolation transformer. Lots of zincs, not sure what else to do. There is no room on the shaft for a anoid, so I think I will have to make a grounding divine that rides on shaft inside of the hull.
Pain I am also not sure about. I know there is a realy good undercoating but I am note sure what that is, and then this Vesel is not really yachty, so I don't think I need to worried about a supper high gloss gourgus Finnish. I know rustolium makes some good paints. Not sure that thought out hers will have for me but I do want to here.
Obie
 
I have an aluminum boat now, so this should be a bit different.

I think it will be different. Rust protection and paint will be incredibly important.


There is no room on the shaft for a anoid, so I think I will have to make a grounding divine that rides on shaft inside of the hull.

There's nothing unusual about that. The resistance between the engine and the shaft brush inside the engine room should be around 1 ohm. We have two brushes like that - one on each engine.


I know rustolium makes some good paints. Not sure that thought out hers will have for me but I do want to here.
Obie

We're keeping a "workboat" finish ourselves.

Rustoleum, I believe, isn't appropriate for outside the boat. I do use it on inside hull areas because it's much less obnoxious with fumes, etc, since we liveaboard. On the outside, you pretty much have to use an epoxy paint. It will be two part - selecting the primer and topcoat is religion with steel boats. You'll need to talk to a bunch of people to figure out what's best. I'd be very interested in your findings.

We use PPG Amercoat 235 for priming and 229T for topcoat. There's a lot that I don't like about 229T and I'm probably going to switch that.
 
Greetings,
Mr. O. While there's not much wrong with Rustoleum, POR15 is a far superior coating for steel IMO. No UV protection so inside only.
 
Greetings,
Mr. O. While there's not much wrong with Rustoleum, POR15 is a far superior coating for steel IMO. No UV protection so inside only.

Firefly! I didn't know you had a steel boat. Glad to know you have some direct experience with this to share.

Rustoleum is significantly less expensive and for inside hull areas, they're more protected so as long as they are rust free, they don't need much. Rustoleum is also easily obtained online or in Home Depot and even Walmart. I think it's about 1/3rd the cost.

I like the Rusty Metal Primer and Gloss White topcoat. They're oil based but clean up pretty easily. I use Corroseal for rust treating although you'll likely want a couple of needle guns.
 
I am on a plane headed back to Oregon. So starting Tuesday I will be working on the girl full time trying to get her back in the water ASP.
Great forum, thank you all for your encouragements and help. I tend to kinda avoid the forums, just because of the responses you get back on so many of them. But this forum feels a bit different. There seams to be a lot of like minded people trying to help each other with real advice and intelligent toughts. Thank you all for allowing me to be part. With a bit of luck most things will go pretty smooth and she will be back in the water inside of 30 day. I will keep all posted.
Obie
 
Jeffrey,
I thought POR-15 just required that the loose stuff be brushed of prior to application. And where exposed they have a coating called (I belive) Chassy Coat frequently used on car frames. Fairly user friendly and a very high performing product.
 
Jeffrey,
I thought POR-15 just required that the loose stuff be brushed of prior to application. And where exposed they have a coating called (I belive) Chassy Coat frequently used on car frames. Fairly user friendly and a very high performing product.

POR-15 is good stuff. I've used it. The real problem is that if you get any of the material on the can lid edge, it'll seal the can.

I think for the price, Corroseal + Rustoleam primer/topcoat does as good a job for interior hull surfaces. Neither POR-15 nor Rustoleum are strong enough for a full outside, salt-water environment, IMO.

Using Corroseal is easy and binds the rust immediately giving you a week or more to cover with primer. That works really well in a do-it-yourself mode.
 

Latest posts

Back
Top Bottom