Buying a PDQ Trawler Cat

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NDM
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Buying a PDQ Trawler Cat

Post by NDM »

Hello,

Just joined the forum as I am going tomorrow to inspect a 2003 Pdq mv34 hull#22. It has been on the hard for the last two years. I would appreciate some wisdom from the group here. First of all, does anybody have recommendations for a surveyor near Plattsburg, NY area? And a engine surveyor also. I was planning on doing an engine survey myself. My thinking was to just launch the boat and do a sea trial checking for things like engine temperature, speed, rpm, smoke, noise and vibration for a few speeds like idle, 7 knots, 14 knots, and wide open. Is there anything else that a surveyor can do besides monitoring those parameters? Towards that end, does the group have some table that I can use to check the performance of this engine. It has a pair of 75 hp and 3 blade props that have been removed and still in a box after tuning. Don't know the dia and pitch yet. Snowdog has a lot of info for 100 hp engines, but is there something for the 75hp?

Have anybody measured the noise level at different point of the boat at say 13 to 14 knots? I have an app in my iphone that is pretty accurate for measuring the sound level when compared to the expensive sound meters. Just wondering what should be the db level in the inside helm when cruising at 7 and 14 knots. Can you carry on a conversation without shouting? Can you watch TV?

Looking through the postings I noticed that most people have 2005 or 2006 boats. Are there members here who owns the earlier hulls like the one I am buying: 2003 hull#22? I am sure I will have lots more questions next question, but it would help me decide on putting a deposit on this baby if I could get some of my concerns answered. Thanks.
deising
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Re: Buying a PDQ Trawler Cat

Post by deising »

Hi, NDM.

I can't give you anywhere near all the answers to your questions, but I can offer this:

I wrongly assumed that the 1500 hour 75HP engines in our candidate boat would be in good shape. Unfortunately, the port engine had a few semi-serious issues that required several thousand dollars to correct. Fortunately, Stuart Yachts stood behind their work and made good on a major portion of it with the failed turbocharger. I will not buy another cruising boat without an engine survey because of that.

Our engines vibrate pretty heavily at idle, but smooth out about 1,000 RPM. We never measured noise levels, but we do most of our running at 2200 RPM and with the cabin doors closed, we are not bothered by the sound level. Conversation is easy; not sure about watching TV. We have enough trouble understanding TV dialog in a quiet room at home. ;-)

The rubber gaskets that seal the engine access lid can age and distort. If they are missing or otherwise not sealing, you can get a lot higher noise levels from the engines. Otherwise they do a great job. Just remove the lid with the engine running at speed to hear the difference.

Make sure you monitor the temperature of both engines at WOT. If you see the port engine overheating, that is apparently very common. Read up in this forum about that phenomenon.

Good luck!
Duane Ising
m/v Diva Di
Punta Gorda, FL
2006 PDQ MV 34 - hull 91, 75HP, 3-blade
NDM
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Re: Buying a PDQ Trawler Cat

Post by NDM »

Thanks Deising,
So you did not have an engine survey done before purchase? Did you even have a sea trial, if so how detailed? Does anyone have a recommendation for a good engine mechanic in the Plattsburg area in upstate NY? That is the part that concerns me the most, especially because the boat has been on the hard for the last two years.

So for a 75 hp engines with 3 blade props (unfortunately don't have the dia x pitch yet), what is the WOT rpm, speed, and temps?

Also how do the turbos fail? Is there any signs I should be looking for during sea trial?

NDM
duetto
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Re: Buying a PDQ Trawler Cat

Post by duetto »

hi ndm,

we have had hull #23 for 12 years. we also have 75hp w/3 blade props (15x13). you can search my posts for a lot of things we dealt with over the years.

i'll try and do a quick answer to some of your questions:

we have 3300 hrs on the engines. 2 things we did that transformed the boat: 1) had stuart yachts add the mid-shaft cutlass bearing. completely solved dripless seal problem 2) had heat exchanger core pulled and completely remove "black goo" inside the bundle. unlike most, our starboard engine runs approx 5 degrees warmer (185 degrees @ 3350 rpm). we run hours on end at 3350 which usually is around 13.5-14 knots, fully loaded.

we drive inside at lot of time in rough conditions. noise level isn't unbearable but i'm not sure i'd watch tv.

if you have the entec genset, i'd recommend switching to a 110V AC pump for raw water pump.

get rid of the macerator and switch to a sealand diaphragm pump.
john & diane cummings
duetto mv34 #23
deising
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Re: Buying a PDQ Trawler Cat

Post by deising »

NDM,

No engine survey, just a vessel survey and sea trial. I don't have access to the specs right now, but I believe 4200 RPM in neutral WOT and 3,800 under load WOT.

Our turbo failed because the yard had it rebuilt and an oil seal failed so that it let engine oil pour into the air side of the turbo, pumping oil into the intake manifold and the cylinders. Didn't really harm anything except for the 1 quart per engine hour oil loss. Glad I found that one right away.

My gauges read 175F on the stbd engine unless at high cruise power, then it jumps to 185 or so. The port engine will quickly go past 200F at that same high power setting, so I have to run it slower and let the stbd engine carry more load. One owner with the same configuration needed to reduce the prop pitch in order to solve that and that is on my list.
Duane Ising
m/v Diva Di
Punta Gorda, FL
2006 PDQ MV 34 - hull 91, 75HP, 3-blade
NDM
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Re: Buying a PDQ Trawler Cat

Post by NDM »

Thanks Duetto and Dising, good data points and recommendations. Yes, it does have the Entec genset and switching the rw pump will on the checklist.
I am hopeful that I can get 14 knots at 3350 rpm and only 185 degrees. That is my baseline. I will drive up there now and take a look, but the sea trial will probably be another month.
NDM
deising
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Re: Buying a PDQ Trawler Cat

Post by deising »

You are welcome, NDM.

Keep in mind that all cats are weight sensitive. For our sea trials, we had minimal water (saving 600 lbs) and fuel (saving about 700 lbs), no provisions, and not much gear on board (saving lots more weight). We did have 4 people and a light dinghy/engine, and saw 16 kts at WOT with a clean bottom and running gear.

Once we loaded her down for a long cruise, we were lucky to get 14 kts at WOT, and usually had to be happy with 12 kts to keep the engines from overheating. We don't mind doing 80% or more of our cruising at a very economical 7.5-8 kts, so that is OK for us. We hope once we get the port prop pitched a bit less, we will see the overheating go away and we can use the high speed regime more confidently.

One more thing to check is the condition of the drain pans on both AC units. Our fwd unit was still working, but the bottom of the compressor was so rusted, we wound up replacing the whole thing. Surveyor and I never caught that one, either.
Duane Ising
m/v Diva Di
Punta Gorda, FL
2006 PDQ MV 34 - hull 91, 75HP, 3-blade
duetto
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Re: Buying a PDQ Trawler Cat

Post by duetto »

ndm,

remember one thing, 2003 was the last of the "early" boats. they are significantly lighter (chnges to fly bridge /head , galley 2005). we made 18+ knots on our sea trial (low fuel, no water, 4 aboard). as i stated, no wind we'll do 13.5-14 all day long. on the early boats i think that the engine overheating comes back to heat exchangers that have "crap" in the centers between the tubes. yanmar/pdq issued a bulletin by engine number but i BELIEVE it went much further than the numbers given. i'm not saying not to buy based on engine temp, but i'd be prepared to pull and thoroughly clean the the bundle. we had it done after 6 years and it was like a miracle.

good luck, it's a great boat.
john & diane cummings
duetto mv34 #23
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Re: Buying a PDQ Trawler Cat

Post by rhumbline2 »

Yes, It is a great cruising boat. All of the comforts of home. Great fuel economy. Very easy to dock. We use our boat a lot for day trips while other cruisers (mostly single screw sailboats) sit and sit at the dock.

I too had engine overheating problems soon after I bought my PDQ in 2009. I had a mechanic do a LimeRid treatment on the engines and it helped considerably. A couple of seasons ago, I had a stuck thermostat that was giving me overheating problems.
I have that black gunk showing up in my port engine AGAIN and it is wanting to run hot - but not overheating. I flushed and flushed the port cooling system a couple of years back and it made a big difference. When I get to a dock for a few days, I'll be doing it again - perhaps with an off the shelf radiator flush. I also turned the clam intakes to point forward.

My boat is loaded down pretty well with cruising gear and twin 30 gallon deck mounted saddle tanks. I usually cruise at 13kts plus or minus at about 3300 rpm.

One of the best modifications I've done to the boat was to replace the Entec with a Northern Lights 5KW generator with a hush box. I measured and measured and remeasured to make sure it would fit thru the hatch. I think the installers had about an eighth inch clearance getting it in.

Four 80 watt solar panels mounted on the back porch shade area was a great addition to the boat too.

James Mills
Rhumbline
Hull 27
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