[newbee]

New guy here with a project.

The boat is a 1972 wood hull Youngquist 36' flybridge cruiser. Hey, hey stop laughing thats not nice!!
I'm told that the builder, Con Youngquist from the Seattle area was a highly respected fish boat builder and she is sturdy and purty. The story I've been told is that when his order book went quiet in the early 70s he tried to keep his best shipwrights working by trying their hand at some pleasure boats. I heard he's gone now, but sounds like a was a good character so I'd like to be a good steward of his handiwork. If I can ever figure out how do do it I'll post a picture of her. I bought her knowing the propulsion was on its last legs so now I'm dealing with that.

She is/was powered with twin Perkins T6.354 165HP. They still run but they are pretty smoky and I don't want to re-name her the Exon Valdez so I was/am leaning towards re-powering.

Gears are Borg Warner 72C Velvet Drives 1:1 direct to Walter V-drives RV30D ratio 2.09:1.
Shafts are 1 1/4" and props are Michigan 4-bade 22/21.
Displacemet is 21,000 lbs and LOWL is 34. Hull is modified V semi-planing.

I cruise the Pacific Northwest with my wife and kids so I like to run at a not too frenetic 1,600-1,800 RPM. With the old Perk 165s she could hit >16 kts north of 2,000 RPM and 12 is at 1,600PM. I like the option of mid teens if we need to get somewhere but I'm going to do 80% of my 100 hours per year at 1,700 RPM.

Perkins/Cat have 135HP and 185HP but nothing that matches my old HP. I'm told the higher HP will necessitate changing my V-drives to RV40 (one with idler to deliver clockwise shaft rotation)

Now I'm not sure if my shats or props are even right. I'm finding it hard to locate prop and shaft formulas. I understand some refer to it as a black art, but surely there are some guidelines etc.

HELP!!!

Thought I'd throw it out here for discussion if anyone is up for it.

Thanks in advance for any and all thoughts.

If there is any interest, I'd be happy to chronicle my tale of woe on the forum from start to finish.

Fairwinds everyone,

Grant

[Loren Schweizer]

Repowering will be costly.
Have you considered a rebuild?
Check with the 'PerkaPillar' folks in your area and see if they offer an oversize piston/ringset kit which you can drop into the newly line-bored holes.

[tri - star]

To newbe:

A key word in your post is: SEMI-PLANING.
When you hang out in this zone - fuel economy can drop
like a stone. - Over a certain mph.

We all, would like to belive that: the original builder, did
a careful job - of making a fully INTREGATED design.
All the way; from the dihedral aft - to the projected
weight - to the RPM/hp and anticipated prop speed.
A VERY NARROW band of RPM and cruising speed was
established, as a bench mark.
- Right at the beginning.
- Well before pencil was put to paper.
- Or saw was set to wood.

It's way to late, in the game, to look for any significant
gains in speed. - With more horses. - Or magic gears.
(With the hull..maybe. - Will save that for later....)

Even if she does go a bit faster. The fuel rate will quickly
escalate to a point where it will be like throwing handfulls
$ 50 bills over the stern.
{ Yeah... I know guys. That's not unknown to happen in
the world of yachting......As I know well, myself.}

Anyheew... it serves to establish the most economical
fuel, flow rate - tied to RPM. At the PRESENT, best
cruising speed. - And live with it.
By the way - an accurate "fuel flow to RPM/mph meter"
is one of the most cost effective gizmoes - one can
have on board. In my opinion.

In summation:
I will be quite suprised - if careful TESTING, will indicate
that any real jump in power is advisable - or useful.
Also; the slower, older diesels - often have amazingly
long life spans. So sometimes; re-building is a better
choice, over re-powering.
(As also suggested above by, Loren Schweiser.)

So I suggest that the most productive procedure is:
- Find the most TRUSTED diesel mechanic and/or
dealer for engines, in your realistic hp range.
Close to where you dock.
15 mins. with them, will answer a lot of your concerns.
i.e.
A lot of water has gone by - since Perkins started
making diesels - so if you do decide to re-power, be
open to considering - on their advice:
- Maybe.........going with a different manufacturer.

Good Luck and Cheers !

[TSI AV]

Hi,

Newbee, just few questions / suggestions:

1. Do You want her to be faster ?
Very doubtful... Especially, if calculations of propulsion transmission are lost... but, of course, everything can be recalculated. But would not recommend.


2. Is that possible to trace running hrs of her engines ? Please, try to find out.
If she made 100 rhrs / year since 1972, then, may be even not necessary to rebuild...

If You find out, that total rhrs since last overhaul (if any) appx 15 000 hr,
dismantle the engine, take all measurements.
Only then it's possible to make a decision. (overhaul or replace).
P.S. Sometimes I have to deal with engines of same size what have 60 000 - 80 000 rhrs ... and one even 120 500 rhrs...

3. I find, that Your boat is great, special. If I understand correctly, not so many people have the same boat...
So if You keep original engine, that will be very respected (my opinion).

Best regards,

Andrei

[newbee]

Originally Posted by TSI AV

Hi,

Newbee, just few questions / suggestions:

1. Do You want her to be faster ?

No, her speed capabilities are perfectly fine. I will rarely use the speed she already has, but I'm glad there is an extra 3-5 kts in her if we need it from time to time. We will spend most of our time running at 1,600-1,700 RPM which gives me 12 kts.

Originally Posted by TSI AV

2. Is that possible to trace running hrs of her engines ? Please, try to find out.
If she made 100 rhrs / year since 1972, then, may be even not necessary to rebuild...

Neither engine is original, but the serial numbers reveal the manufacturing dates as 1976 (S) and 1979 (P).

Port was a Perkins certified factory re-manufacture out of Pacific Detroit Diesel in Kent Washington (they don't re-man anymore unfortunately) . It was instaled by North Harbour Diesel in Anacortes Washington, and has 1,600 hours since re-man. I think the turbo is shot on it and it could use some TLC but it is probably fine for now.

Starboard had about 3,500 hours. We knew it had a bad #1 cylinder so it has already been taken apart by a very experienced and trusted diesel mechanic. He thought it had already been remanfactured once and questioned whether it was good value to go further.

I've talked with Trans Atlantic Diesel on the east coast and I get a good vibe about their core exchange re-build program. The shipping is an issue bt I have not ruled it out.

Originally Posted by TSI AV

3. I find, that Your boat is great, special. If I understand correctly, not so many people have the same boat...
So if You keep original engine, that will be very respected (my opinion).

Best regards,

Andrei

Thanks

[newbee]

Originally Posted by Loren Schweizer

Repowering will be costly.
Have you considered a rebuild?
Check with the 'PerkaPillar' folks in your area and see if they offer an oversize piston/ringset kit which you can drop into the newly line-bored holes.

Thanks for your thoughts.

Yes I am still considering re-build. At first id did not seem to make sense because the price dfi between a new and re-build was too small, but now I'm starting to see that the cost of all tha other changes that re-power would force may make re-power not viable.

[newbee]

Originally Posted by tri - star

To newbe:

It's way to late, in the game, to look for any significant
gains in speed. - With more horses. - Or magic gears.
(With the hull..maybe. - Will save that for later....)

Not looking to go faster, so I agree.

Originally Posted by tri - star

Anyheew... it serves to establish the most economical
fuel, flow rate - tied to RPM. At the PRESENT, best
cruising speed. - And live with it.
By the way - an accurate "fuel flow to RPM/mph meter"
is one of the most cost effective gizmoes - one can
have on board. In my opinion.

I'd love one of these gizmos. Any specific recommendation?

Originally Posted by tri - star

So I suggest that the most productive procedure is:
- Find the most TRUSTED diesel mechanic and/or
dealer for engines, in your realistic hp range.
Close to where you dock.
15 mins. with them, will answer a lot of your concerns.
i.e.
A lot of water has gone by - since Perkins started
making diesels - so if you do decide to re-power, be
open to considering - on their advice:
- Maybe.........going with a different manufacturer.

Good Luck and Cheers !

Thanks for sharing your thoughts.

[newbee]

Let's see if I can figure out how to post a picture of the old girl.

Well what do you know....it worked

[newbee]

Here's a web album of her out of the water at survey.

http://picasaweb.google.com/gcscccolby/Youngquist

[Garry Hartshorn]

Have a look at a Lugger L1066T it's a pretty close match I also believe that it is the same short block as the John Deere 6068

[K1W1]

Hi,

If you can rebuild the old ones you wil not look back.

The block, Pistons, Rods and Cranks are very very robust and long and hard wearing items in those engines

They were not known as "Perkins perpertuities" for nothing in their non Turbo versions.

Every one I have ever seen was a bit of a smoker when first getting going.

These guys look like pretty well established reman engine boys, it might be worth getting a comparitive quote from them.

http://www.foleyengines.com/home.html

Good luck and please keep us posted on what the outcome of your rebuild/repower dilema is.

[tri - star]

To newbee:
Nice looking boat....worth fussing over.
As far as a " fuel flow to RPM/ mph meter " goes - I don't have a specific
unit to reccomend.
Although; there are several directions I will be going for myself, in search
of such instramentation - soon.
i.e.
Many HYBRID cars have devices like this. To let the driver know when
they are in the most economical gear. Or when to shift up or down.
However, hooking such a device up to an " old school " engine may be
an issue.

So my first stop will be a lab or dyno. shop where they do this type
of testing all the time.

Cheers !

[Loren Schweizer]

Originally Posted by newbee

Thanks for your thoughts.

Yes I am still considering re-build. At first id did not seem to make sense because the price dfi between a new and re-build was too small, but now I'm starting to see that the cost of all tha other changes that re-power would force may make re-power not viable.

Read K1W1's post and pay heed.
The old rule of thumb was that an engine transplant, including labor and ancillaries, cost roughly double the price of the replacement motor.

May be even more today w/increased labor rates.

[TSI AV]

Hi,

If rhrs are true (3500 / 1600), then go for dismantling / only checking first.

If You have trustable workshop, ask them to dismantle and measure everything, especially:

1. Liners dia. / ovality. If it's ok, then just do some honing.
2. Crankpin dia. / cone of crankpins and their bearings.
3. Main journals dia.
4. Check 1 or 2 main bearings. How they look like ?
5. Eliminate "watermarks" (if any) on crankshaft.

If all a/m ok, You will have to do only minor overhaul.

Normally, with such rhrs, it's only necessary to check injectors, belts, valve clearance, filters...

But, considering situation "low rhrs but overhaul long time ago", I would replace piston rings, injector springs, valve springs for sure.
Just becuse they are "tired" to be compressed for long period, .

As K1W1 mentioned, older engines blocks, crankshafts, pistons are robust.
So, I hope, that Your engine is one of those...

Please keep us posted bout Your project.

Best regards,

Andrei

[K1W1]

Hi,

I have bee thinking aboutn these engines a lot since replying to this e mail yesterday.

I was involved in a number of Truck repowers replacing a BMC 5.7LT Diesel with the 6-354 in the early 80's. I still can remember that the CAV Injector Crack off pressure was 175 Atm and the Fuel Filters PART No. was CAV 7111-296.

For anyone interested in reading about these old dinasours I found an interesting history of the engine family here:

http://images.google.co.uk/imgres?im...%3Den%26sa%3DN