Accidentally bought a trawler ;)

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Gwilliams

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Never really occurred to me, what I had done until describing the boat to a friend that is huge fan of trawlers.

Had been (probably accurately) describing it as a semi-displacement hull but once running it realizing how slow the damn thing is (;)), a light bulb went off and it all made sense :eek:

Boat is an '87 36' DC w/twin 270 HP, 350 cu in Crusaders and 6.5 KW Kohler generator.

Have owned it 2 months now and had it away from dock last weekend for the first time since the sea trial.
Loved it!

We were shopping at the bottom end of the budget for aft cabins and most we found in that range stopped being boats 3-4 yrs ago and became cottages.
As did this one.

As in, interior was gorgeous but nothing mechanical functioned :thumb:
Luckily, I've done this all my life and am able to do most of the chores myself.

Sold an '86 Marinette 32' sedan/bridge (2nd 32', third Marinette) that was perfect to buy this project, knowing we'd spend most of the end of this season at dock (as in, a cottage) while I sorted it.

Top of list is motors. Starboard was recently rebuilt but port is orig.
On sea trial both motors ran warmer than I like so I replaced t.stats (160*) and topped off antifreeze (closed cooling) before going out last weekend.
At idle in neutral I saw approx 180* (new gauges) which is where it stayed under load up to approx 2800 - 3000 RPM.
Anything above that they climbed to 200* (which I don't like) and stayed there.
Based on feel and spray off the hull, I suspect the difference between 2800 - 3200 will only be felt at the fuel dock.

Overall I will say though, I am way impressed with this boat. The fit and finish, attention to detail, glass work is equal w/almost anything I've seen.
And i used to build vacuum infused 28' sport fish boats for the most anal guy I've ever met.

I am particularly impressed (as a glass guy) w/the glass piece that surrounds the ceiling of the main salon. Has built in wire chases, cavities for curtain tracks (full length of cabin!) and the gauge/dash panel for the lower helm and finished in gel coat.
This is all one piece w/not a single straight line anywhere. Would have taken hundreds of hours to get the mold right.

The picture is while anchored off the campground at Kellies Island in Lake Erie Ohio and the short video is coming around the west side of the island and passing the West Bay Inn. Has free dockage to enjoy lunch and a beverage and to see some of the best sun sets in the world.
Our wives were nice enough to give my brother (boat shopping again for first time in 20 yrs) and I hall passes for the weekend to play on the boat.

Anyhow, thanks for letting me play and I thought you guys might like to follow along w/the project.

Gary
 

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Nice looking boat. You have lots of fun times ahead, congrats.

Cheers, Bill
 
I'd be happy with the performance as is, in luding the 200 degrees over 3000. Nice vessel. Welcome to TF.
 
Nice boat, welcome!

There's been some talk around here about cleaning out heat exchangers with an acid-based solution like Barnacle Buster, Rydlyme or just plan phosphoric acid (diluted). Several folks reported running 10 degrees cooler after.

Sounds like a very good thing to do with a recently-purchased used boat, I'm going to give it a try.
 
Thx for all the compliments guys.

Just reread the Mainship 36 thread and its great info as well.

Couple more weekends of fun and then it goes on the hard and the real work begins.

If weather cooperates we plan to put some miles on it this weekend and this time w/my GPS and note book so we'll get a base line.

Next season should be big fun.
 
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Welcome Gary, great to see you bringing "that ol' girl" back to the dance! You will grow to love her. I love that aft enclosure set up. Looks like a hardtop? is that canvas on the fly bridge or hardtop there?
We have the 40 DC with the big block engines. The suggestion by CaptTom brings the point to mind that you may want to find WHY you are seeming to run a little hot. prior to assuming you need rebuilds for the engine. Lots of things could cause high heat. Poor water flow, clogged heat exchangers ETC. Gauges do lie. sometimes. You seem to have the experience to sort all of that out, ENJOY. :dance:
Dave.
 
Ok...so...just to confirm, as it has not been stated as such, and someone has to ask...is it a Mainship 40..? It looks like one, as as the old saying goes, if it looks like a duck, quacks like a duck...
 
Peter, stated in post #1, it is a 36.
I think the hard top makes it look bigger.

Dave, hard top aft, canvas bridge enclosure.
Sea trial and closing was delayed as we debated motors "actual" condition.
Port (orig) motor showed low to no oil pressure at idle. Oh, and neither would even start for sea trial.
I like to gamble though, so.....

I replaced all gauges on bridge and oil pressure sending units.
And thermostats.

We now have 20 lbs of oil @ idle but doesn't rise w/rpm which is very odd.
Stbd idles @ 20 but goes to 60 @ speed so we know that one got a high pressure pump @ rebuild.

On elevated operating temps above 2800, I haven't been through pumps or strainers yet.
At first glance, it appears that objective is to establish health/power of both motors then go from their.
Have been considering power options but don't think I'm willing to go beyond small blocks due to necessity in changing manifolds, plumbing etc.
One option I do like is addition of Vortex heads to existing motors.
Approx +30 hp's per side.

Really enjoying Tony B's fuel use graphs and in looking at them, it appears to me that there is a sweet spot @ 3K RPM.
Bellow and above that rpm, the boat needs more rpm to gain 1 mph than it does @ 2980 rpm and 15.8 mph and .9 mpg.
If I'm doing my math right, that equals 14.23 gph @ cruise which I'm OK with.

What I really like though is that tells me the 270's have enough power and w/existing props I only need them to be happy @ 3k which I think I can do.
Clear as mud?

Dave, PS, we like the additional living space of all the canvas but I like the looks of the boat w/o any of it.
If I was single, the hard top and all canvas but bridge Bimini would be for sale ��

In picture, left are new gauges, rt is new.
Drastic, affordable improvement.
 

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Gary, Yes that is odd with 20 lbs oil pressure at idle and no change with change of RPM? Odd indeed. I like the side enclosures off as well. Not much cold weather around here to hide from. Keeps things less dirty in winter when all zipped up!
We do other stuff when it's freezing out. New gauges look nifty, appear easier to read at a glance. The hard top for the aft area is the best. Wish ours had been optioned that way. Too much trouble for me to change it now.
Great looking ship you have there. Cheers
Dave
 
I too love the look of this boat can't wait to see what you do with her from here on. Please post pics as you do improvements
 
Welcome Gary. I started to read your post thinking "There better be pictures!" Not only pictures, but a video! Well done. I did not know we could post videos!!! Thanks. Great looking boat.
 
Welcome aboard!

Have you changed the oil and filters? That might affect the readings?
 
I did clean my cooling system with Barnacle Buster. Put it in and let it sit for about 7 hours. Port engine dropped 5 degrees and the starboard engine dropped 10 degrees. We just bought the boat about a year ago. I have not had the heat exchangers apart yet, but the temperature readings were based on 200 hours run time last summer so I am confident that it did make a difference.
 
I recommend a portable IR temp meter. About $50 or so. There is so much that make dash gauges inaccurate. Sensors, grounding, dual stations, etc. 160 deg stats are correct. 180 deg at idle is not; but right now the gauges are not believable.
Take a IR shot of the thermostat housing, at idle, and then during a cruise run after at least 20 minutes. It shouldn't exceed 180 deg at the housing. Remember after this point, that same water has to cool the exh manifolds. You don't want that to exceed 200 or so at EM exit. As you get the remote gauges sorted out, then it becomes a good reference to see early trouble. Right now though, I recommend at least a temporary run into a mechanical oil pressure and the portable IR temperature trick. At one point, I really got into the various temperature readings on my GM motors; engine output temp. heat exchanger input and output temp, and raw water output temperatures. Knowing a base line (normal) set of numbers helps in debug.
To oil pressure. A fixed 20psi reading over rpm is hopefully not correct. Hopefully a stuck sender. Check with a mech gauge.
 
Oil pressure gauge: With the engine running, turn the key off then back on. Does the pressure drop to zero?
Swap the oil pressure sender to the other engine. Does the problem move. If no, try the same with the gauges.
Good luck with the boat. If you are getting 0.93 mpg at 3000 rpm with a 36' gas boat your doing good.
 
I did clean my cooling system with Barnacle Buster. Put it in and let it sit for about 7 hours. Port engine dropped 5 degrees and the starboard engine dropped 10 degrees. We just bought the boat about a year ago. I have not had the heat exchangers apart yet, but the temperature readings were based on 200 hours run time last summer so I am confident that it did make a difference.

I had a heating issue after my purchase some 10+ years ago (my--- time does seem to fly!) that I cured with new oil coolers, risers & elbows. But the thing that really made a difference was removing the heat exchangers along with their covers. Now with the tubes exposed, it took less than five minutes to rod them. THAT REALLY MADE A DIFFERENCE.
 
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May I ask what kind/brand of gauges you have installed? I may be changing out mine in the near future, Thanks.

Kevin
 
Diver Dave's suggestion for an IR (or laser from HF) to get better temperature accuracy is on the mark. Because I went through a similar experience after purchasing my Silverton, I think your problem is real and most of it in the heat exchangers.

But I want to caution you about risers and elbows. The recommended change period for risers is 10 years with some extremist claiming 5 years. If a $200 riser fails............it will take the engine with it. And having changed risers along with exhaust hose, I found removing the hose from the muffler first made things a great deal easier.

I changed my risers/elbows back in the summer of 1996. I plan to replace them after the upcoming season.
 
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In my Southern Latitudes, where the ocean has more salt, GM risers and RW cooled elbows are on 4 year schedules for replacement. Anything over 4 years is very risky. I had a OEM elbow clog on a passage one time; the exhaust hose started burning, smoke out the exhaust. Luckily, with a V engine and one still good side pumping water, the fiberglass muffler did not burn down below deck. That Crusader elbow was 4 years old. Been through 4 replacement cycles and at 4 years, the cast iron passages are very small, lots of scaling rust.
As a side note, I did a FW flush after most every use for a full 4 years. Still a shocking amount of scaling free rust at 4 years.
 
In my Southern Latitudes, where the ocean has more salt, GM risers and RW cooled elbows are on 4 year schedules for replacement. Anything over 4 years is very risky. I had a OEM elbow clog on a passage one time; the exhaust hose started burning, smoke out the exhaust. Luckily, with a V engine and one still good side pumping water, the fiberglass muffler did not burn down below deck. That Crusader elbow was 4 years old. Been through 4 replacement cycles and at 4 years, the cast iron passages are very small, lots of scaling rust.
As a side note, I did a FW flush after most every use for a full 4 years. Still a shocking amount of scaling free rust at 4 years.


Sure..... a fresh water flush is the way to go! You pointed out a problem where the water passages plug which is serious! Bu t a rust hole allowing raw salt water to enter the exhaust system is an engine killer.

Here in Massachusetts, guys just seem to overlook, not care about their risers to my astonishment. One guy I know had a rust hole in an elbow that allowed wet exhaust to escape. His fix.......epoxy! The same guy has another boat with 454's (1989) whose risers/elbows are originals.

My risers remain cool with the engines running but I have no intention of going beyond this season without changing them. Much less expensive than changing an engine AND I will try to implement provisions needed for flushing!
 
My experiences were on a Gen IV 454. My point on the FW flush is that it did not prolong the life of the cast iron. It might help the coolers, but not even positive about that. Salt % in MA is certainly lower than FL. Plus the boating season south is all year.
 
Dave-- so from your experience, the only benefits provided by doing a flush is the purging of salt? But if that is a benefit, why would not the life of the cast iron be extended? Salt is the corrosive agent that results in rapid rusting compared to freshwater.

I gave thoughts to adding a flush some years ago, just never got around to making it happen. Later I thought that after 5 years or so, why bother. You're mention of it just reminded me that after I do change my risers, introducing a fresh water flush should also be incorporated.
 
I was surprised at the data. Since I did this, someone else mentioned that chloride attack is at its worse when warm and when in motion. That seems reasonable, but I have not done more research. The iron is pretty stressed with hot exhaust temperature at one side of the wall and fairly cold, fast moving raw water on the other side. The salt beating up the scaling iron surface.
Maybe the next experiment would be simply hang a new riser in salt water for 4 years? dunno. Note that most of the water drains out of risers when engine is stopped.
 
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Also, here is some of the data from the NASA Aquarius satellite.. It measures surface salt content of the world's oceans. A huge diff from MA and FL.
 
Wow, you guys have been busy ;)

I wasnt getting new post alerts.

On engine temps, I replaced sending units too w/no change.
I have an IR temp gun but based on above, wouldnt expect to see anything.

If weather permits, Im going to start going up on weekends and doing chores.
I will pull heat exchangers and have them boiled out and change pump impellers which I no no history on.

Will change oil/filters too.

On cosmetics, I am having all new stripes and graphics made, in blue to match canvas.
Should really pop and make it look 10 yrs newer.

Got our new carpet installed last fall and that was a huge improvement to interior.
Now I have 3 TV's to hang and see if theres a way to make all 3 work off of one antenna.

Also need to do final install for my dinghy davits.
Ran a 10' inflatable (w/inflatable keel and wood floor) w/a 25 hp motor last yr and was disapointed in how it ran w/that much power.
So I decided over the winter, the answer is to build one.

Bought a set of plans for the 10' skiff "Squirt" from Glen L and am underway.
I measured the transom on the Mainship though it is only 11' so to prevent the dinghy or motor from sticking past hull sides, I modified the design to inset the motor a foot.
Am restoring a '1981 35 hp Evinrude for it.
I really like the dinghy design and has the '40's era lines to it w/a semi barrel back after section.
 

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I think you will be wasting both time and money "boiling out" a heat exchanger. Mine soaked for 4 days at a radiator shop and the only change was the exterior paint peeled off.

The fastest, least expensive approach to "cleaning" heat exchangers is to rod them yourself. Just my humble opinion.
 
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Greetings,
Well, I think I consider myself fortunate in that the water injection for my exhaust is about 7'-9' downstream from the exhaust elbows. That section from the exhaust elbow rises ~3' vertically upwards then traverses about 3'-4' horizontally then vertically downwards and into the water lift "can". Cooling water injection is in the first 1' of the 4' downward run to the can. There is a SS bellows adjacent to the engine and the SS exhaust pipe is jacketed with insulation. I don't expect there is any significant amount of rust inside. I'll have to inspect that some day.
 
I think you will be wasting both time and money "boiling out" a heat exchanger. Mine soaked for 4 days at a radiator shop and the only change was the exterior paint peeled off.

The fastest, least expensive approach to "cleaning" heat exchangers is to rod them yourself. Just my humble opinion.

10-4

I'll look at them.
I'll have to sweat the end of the housing off to get to the tubes correct?
 
I am not sure about that, you will need to look. Those on my Silverton were held with simple bolts, one on each end. I cleaned mine in less than 5 minutes each. I do know that the oil coolers are sweated on so cleaning those things would be both difficult and messy.

EDIT:

I used a SS welding rod for the job but anything will work. A 22 caliber cleaning rod might fit.
 
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