27 H&H QSB 5.9 Engine Install, engine mounts, isolaters and aluminum stringer brackets.

BillD

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25 Terry Jason with Cummins 370 power
Slow and steady I'm close to permanently bolting in the QSB 5.9 480 into the 27 H&H.
Engine was hoisted into place once with the transmission attached and aligned to the shaft to measure the distances width and depth for the front engine mounts and
front aluminum stringer brackets.

Some here have followed the new shaft, stern bearing redo and machining of the inside of the beefy bronze stuffing box and maching smooth the threads
that were on the outside to accept a new PSS shaft seal.

Here's are pictures of where I am in the project.

Custom engine mounts up front to accept the bigger SMX Blue isolators used for the 6CTA, QSC and QSB 6.7s
Cummins OEM front engine mount pic taken side by side to new custom mounts I had welded up.

I made the decison to use the bigger isolaters up front in addition to this size isolator in the back supporting the ZF280A gear and the back end of
the QSB 5.9.

All four aluminum stringer brackets were floated into epoxy beds and leveled side to side. Front to back brackets oare on same plane.

More to follow

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ARC

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Looks great so far. That’s a lot of HP for a 27’. I have QSB 380 in a 31’ and can’t use it. My boat gets squirrelly over 2,400 . I’m never over 2,000. Maybe the H will handle it better.
 

BillD

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I do know the 27 H&H hull is stable at 28-30 knots.

There's about a $1,000 -$1500 price difference between the 380-480.

If the prop calcs are correct and I have the weight of the finished boat close to what was used in the formula

I hope to cruise 22 knots at 2700-2800 rpms with a reasonably light load for the 480.

Yes the extra hp is a waste....but I don't want to go slow when I don't have to !

And at 67 yrs old I'm at risk for the china virus. :eek:
 

ARC

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You will get 22kn for sure. I can get that with my 380 but it will do a ‘crazy Ivan‘ usually to port but you never really know.
 

cb34

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I do know the 27 H&H hull is stable at 28-30 knots.

There's about a $1,000 -$1500 price difference between the 380-480.

If the prop calcs are correct and I have the weight of the finished boat close to what was used in the formula

I hope to cruise 22 knots at 2700-2800 rpms with a reasonably light load for the 480.

Yes the extra hp is a waste....but I don't want to go slow when I don't have to !

And at 67 yrs old I'm at risk for the china virus. :eek:
China virus racist LOL awesome job on the mounts.........
 

BillD

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Is that gell coat? I have to do my engine room.
Yes two coats of gel coat.
I wrestled with gel coat or BilgeKote "paint". The paint being easier to prep for.
But any use of "paint" products on this boat is a no go .

Call me crazy but when I assessed this 27 H&H for a purchase and a refit/repower there were three critical criteria at the top of the list that would either clinch or kill the deal.

1. The hull had to handle safely at speeds 22 knots or better without any "crazy Ivans"
2. the boat had to have fiberglass fuel tanks.
3. That the boat had NO paint on her anywhere, had to be all gel coat!

For the members here who followed the purchase and seatrails late last summer...I ran the boat for 30 hrs. with the 6BT 210 in the boat. Ran her in all types of seas.

Ya, call me crazy but paint and gel coat never mix !
 
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Keelboater

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Looking good Captain. Why did you use 4 short pieces of aluminum for the motor brackets instead of 2 longer pieces? Clearance issues for hoses and such?
 

BillD

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Looking good Captain. Why did you use 4 short pieces of aluminum for the motor brackets instead of 2 longer pieces? Clearance issues for hoses and such?
I don't understand your question ?
The 1/2" aluminum 6081 T brackets are 12" long each. Plenty of room and support for the bigger C isolators

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Keelboater

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I'm sure they are plenty big enough for the mounts. It's just easier to work with 1 long piece on each side because front to back remains on the same plane. It also makes for a stiffer stringer in that area.
 

BillD

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I'm sure they are plenty big enough for the mounts. It's just easier to work with 1 long piece on each side because front to back remains on the same plane. It also makes for a stiffer stringer in that area.
Keel,
The one "long piece" is the hull stringer itself.
In many many marine engine installations the front to back mounts are rarely on the same plane. Higher or lower front to back or back to front.
Side to side the brackets are on the same plane.
That's the reason for removing the engine to float in the brackets with a clamped straight edge across the two opposing side brackets.
 

Keelboater

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Sure, I understand. More than one way to skin a cat and it varies from motor to motor & boat to boat. I've seen quite a few installations with one continuous piece of aluminum and just thought I'd ask. Mine will not have any aluminum angles with the QSB installation because of the motor bed spacing. Instead it appears that I will have to build up the motor bed to suit and the motor sits on top, just like it did with the CAT 3208.
 

BillD

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Sure, I understand. More than one way to skin a cat and it varies from motor to motor & boat to boat. I've seen quite a few installations with one continuous piece of aluminum and just thought I'd ask. Mine will not have any aluminum angles with the QSB installation because of the motor bed spacing. Instead it appears that I will have to build up the motor bed to suit and the motor sits on top, just like it did with the CAT 3208.
What do you have for exact width in inches between engine bed stringers ?
32" is a good width for a QSB using 6" 6081T 1/2" aluminum angle plate.
 

Tuna Pursuit

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Bill, let me hijack your thread

My Duffy has an old school packing glad shaft seal. One option is to install a tube and cutless bearing one each end and a dripless. Is that the way to go? Haven't had packing glad since my old Hatteras
 

BillD

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Bill, let me hijack your thread

My Duffy has an old school packing glad shaft seal. One option is to install a tube and cutless bearing one each end and a dripless. Is that the way to go? Haven't had packing glad since my old Hatteras
what will be the length of the shaft from the stuffing box to the transmission coupler ?
odds are you'll need a front bearing for support like an RE Thomas self aligning bearing
 

Keelboater

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"What do you have for exact width in inches between engine bed stringers ?
32" is a good width for a QSB using 6" 6081T 1/2" aluminum angle plate."

This is not a typical installation between stringers Bill. My motor must be mounted to the top of the narrowly placed motor beds. I will fabricate some stainless interface brackets to suit when the time comes. It's actually easier to do than it is to describe.
 
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