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Senor Falcon
09-13-2010, 08:49 AM
Hi all,

I have a 36ft Falcon Bonito. I bought it with two GM 5.7 and Alpha 1 drives. Engines were good apart from one water pump and a starter solenoid. The drives were noisey and needed complete hydraulics.

I have recently bought two 6.5 chevy diesels, set up to peninsular engines spec and with peninsular parts. They have twin turbo´s on each engine and velvet box´s. The drives are TRS 400´s.

My question is. What do you all think, about this engine / drive combination. I don´t want to cut the transom for older drives, if the benefits are not great. I might have to change the engine bay, to take the extra length (with box´s) of the engines also.

I was thinking of swapping the box´s and TRS drives, for a pair of Bravo drives, or something similar. I think this will keep the original mountin possitions and save a lot of work. There are many questions that need to be answered but I guess the most important is, What would be the best setup, for these engines?

The boat will be used for pleasure only but as the owner of a 21ft Phantom, with 200hp on the back, I do like a bit of speed.

Any information or advice would be very helpful.

Thanks in advance.

Pete

txriverrat2001
09-13-2010, 09:58 AM
I would chat with the guys at boatdiesel.com about the Peninsular engines - They would know more about any known issues/performance etc....

My .02 worth

MILD THUNDER
09-13-2010, 08:15 PM
If the boat is rigged with alphas, going to a bravo setup will be easier than going to TRS. You will have more room in the engine compartment with the bravos.

Senor Falcon
09-14-2010, 03:36 PM
Hi,

Thanks for the tip, re boatdiesel.com, I´ll check them out.

Regarding the Bravos, this was my thought exactly. I do have just enough roon for the existing setup but as you say, I would have more room with the Bravos. The only problem being, the TRS drives and the Velvet box´s came with the engines ( a job lot) so would have to find a reasonable priced pair of Bravos.

Any other ideas are very welcome.

Thanks.

Pete

Senor Falcon
09-14-2010, 04:31 PM
Hi again, I have put some photos and video on here http://s751.photobucket.com/home/FalconBonito/index

If this helps with any advice.

Thanks

Pete

Ratickle
09-14-2010, 07:36 PM
Wow, what a project that would be.

mh1031
09-14-2010, 08:35 PM
Would a Bravo hold up to the torque of the diesels? Very interesting project though. Good luck and keep us up to date.

MILD THUNDER
09-14-2010, 11:23 PM
Would a Bravo hold up to the torque of the diesels? Very interesting project though. Good luck and keep us up to date.

I dont think the 6.5 diesels will make that much torque. Most bravo's hold up behind 450-500FT lbs on a HP gasser motor. I dont see those diesels making more than that, but it will be at a much lower RPM. I am pretty sure merc put bravos behind some small diesels.

Ratickle
09-15-2010, 02:02 PM
I dont think the 6.5 diesels will make that much torque. Most bravo's hold up behind 450-500FT lbs on a HP gasser motor. I dont see those diesels making more than that, but it will be at a much lower RPM. I am pretty sure merc put bravos behind some small diesels.

Specifications
Engine RPO Codes: L49, L56, L57, L65, LQM, and LQN.
Displacement: 6.5L / 397 cu in
Bore x Stroke: 4.06 x 3.82 (in.)
Block / Head: Cast iron / Cast iron
Aspiration: Turbocharged (Borg-Warner GM-X series) Also available naturally aspirated.
Valvetrain: OHV 2-V
Compression: GM Early 21.3:1, GM Late 20.3:1, AMG/GEP Marine 18:1
Injection: Indirect
Power / Torque (lowest): 180 hp (134 kW) @ 3,400 rpm / 360 lb·ft (488 N·m) @ 1,700 rpm
Power / Torque (highest): 215 hp (160 kW) @ 3,200 rpm / 440 lb·ft (597 N·m) @ 1,800 rpm
Max RPMs: 3,400

Senor Falcon
09-17-2010, 09:32 AM
So, with the twin turbo´s raising the HP to 330, they should be pushing more than the 440 quoted? I believe the "X" Bravos are the diesel drives, just not sure if I am better with the older and proven TRS drives?

Pete

MOBILEMERCMAN
09-17-2010, 10:15 AM
You should look into what diesel gear ratios bravos offer..

Senor Falcon
09-22-2010, 02:32 PM
Hi again,

Well, from what I can find out, the following specs should be very similar to mine, the main difference being that mine are standard bores, at 397 and that the electronic version of the injector pump with a brain which will let you have up to 15 psi boost early in the rev range then tail off to 10 psi at higher revs, mine will boost up slower and then I will have full boost from about 2200 all the way up to max revs. So, I guess they get the extra 20HP from the bored cylinders and the boost from the electronic pump. Specs below.

Model: 400TAI-340
Engine Type: Four Cycle
Number of Cylinders: Eight
Bore and Stroke: 4.06″ x 3.82″
Displacement: 400cu.in. (6.554cc)
Fuel Pump: Stanadyne-Mechanical (DB4)
Brake Horsepower: 340BHP at 3600 rpm
Peak Torque: 495ft.lbs. at 2200 rpm

Pete

Senor Falcon
09-27-2010, 07:29 AM
Hi All. Well, it looks like I will be keeping the TRS drives. To be honest, to pay out another 10 to 20 K for drives, was not accounted for. Also, by putting the engines further back in the engine bay, I would have to modify the deck area around the front of the engines. The Turbo´s stick up a lot higher than the sides of the boat, when in the possition of a Bravo setup. So, less $$$$$ and a lot less cutting out, is the way forward, I think?

Would the weight of the engines, further forward, effect the boat in any way?

PS, In front of the engines I have 2 fuel tanks and I have just found out that they are 50 Gallon (imp) each.

Any ideas are more than welcome. Anyone with experience of this situation, and knowing the end result, please share your experiences.

Thanks to all

Pete

old377guy
09-27-2010, 11:44 AM
Mercury made a "diesel" gearset for TRS drives back in the day.Who know that there might not be some of these still around; perhaps Riggs or Mark at BAM could give you a lead.

DollerDriveGuy
10-01-2010, 11:12 AM
No you won't find gears for TRS diesel. But Bravo one X gears will do just fine. So use a Bravo One X.

Senor Falcon
11-26-2010, 01:29 PM
At last I have found time to get back on the boat. Stripped most of the engine bay and removed the (Alpha 1) drives and gimbles.

I made a template for the TRS gimbles and checked the difference, with the Alpha holes, in the transom. They are about the same, wide, but the TRS are quite a bit longer.

Is there a recommended height, for the gimble, from the bottom of the hull, on the TRS drives? Or is the height of the gimble, decided by what height you want the prop shaft? If yes, what is the best height for the prop shaft?

Thanks in advance.

Pete

rschap1
11-26-2010, 03:03 PM
I am a bit jaded after watching my neighbor throw over 6 figures (no kidding) at a 6.5 turbo in his 2500 Suburban...I got say, I would go with a different motor.
There are a very few select castings for blocks, cranks, and bottom ends that are worth a $hi+. Rest are prone to failure. I would not think of a 6.5 myself.

Senor Falcon
11-29-2010, 01:22 PM
Peninsular diesel seem to make a good living out of producing these engines (government contracts and all). It´s too late now, I bought them and at the price I paid, they will go in.

What is a good drive height, for a twin setup, with TRS drives. Also, I need to fit through hull water pickups. I was thinking of putting them through the hull, close to the transom, so that I can fit the valves directly to the pickups and support them on the transom. Is there any problem with this???

Thanks guys

Pete

Senor Falcon
12-03-2010, 11:13 AM
Hi All.

I am preparing the engine bay, for the engines and drives. I will have to do everything from the start, as the old drives were Alpha 1´s

I have pulled out the old mounting crossmember and most of the other things. I will check where the drives were set before, as I have been told that I should stick to this drive height, as the original makers would have set it up as per it´s design. I have also been told that the TRS will move the prop further away from the transom, so I will have to consider this, when fixing the height.

What would be fantastic is; if I could find blueprints for the Alpha 1 and the TRS drives, so I can compare the positions exactly. I would also like the blueprint for the Velvet drive box and the GM 6.5 diesel (I can allow for the added turbos etc)

So, the question is, where can I find these blueprints? Any help with this would be great.

Thanks

Pete

old377guy
12-03-2010, 01:42 PM
Hi All.

I am preparing the engine bay, for the engines and drives. I will have to do everything from the start, as the old drives were Alpha 1´s

I have pulled out the old mounting crossmember and most of the other things. I will check where the drives were set before, as I have been told that I should stick to this drive height, as the original makers would have set it up as per it´s design. I have also been told that the TRS will move the prop further away from the transom, so I will have to consider this, when fixing the height.

What would be fantastic is; if I could find blueprints for the Alpha 1 and the TRS drives, so I can compare the positions exactly. I would also like the blueprint for the Velvet drive box and the GM 6.5 diesel (I can allow for the added turbos etc)

So, the question is, where can I find these blueprints? Any help with this would be great.

Thanks

Pete

Talk to Marc at BAM in Miami

Senor Falcon
12-04-2010, 01:00 AM
Any contact email address?

old377guy
12-04-2010, 11:27 AM
Any contact email address?


www.go-fast.com

Senor Falcon
12-06-2010, 07:00 PM
Have sent email and waiting fo an answer.

Anyone got any idea for mounting these engines, in the engine bay below.

Pete

Senor Falcon
12-10-2010, 12:48 PM
Talk to Marc at BAM in Miami

Emailed Mark on the 4th, no reply as yet. Any other ideas?

Pete

old377guy
12-10-2010, 03:59 PM
Emailed Mark on the 4th, no reply as yet. Any other ideas?

Pete

Have you tried calling; they seemed pretty good in the past returning calls - good luck - Jeff

bajabob 718
12-11-2010, 07:30 PM
well the way i look at it? the back of the motors bolt on to the inter plate.two bolts i would set the motor on the frist . then take cardboard and make a templet and get metal ,cut it like the templet and weld it to fit.

Senor Falcon
12-12-2010, 03:25 PM
Thanks Jeff, I´ll give that a try tomorrow.

Pete

Senor Falcon
12-12-2010, 03:33 PM
Thanks for that Bob. The main problem is, first the transom plate (inner and outer) have to be fitted, to bolt both V8 engines, complete with Velvet box´s, onto them. Not being 100% sure where the transom plates will be, makes this a little harder.

Also, 2 x 564 KG, hanging around, while I make cardboard templates, does worry me a little.

Thanks for your suggestion anyway.

Pete

Senor Falcon
12-14-2010, 04:00 PM
Hi All, My original Alpha 1 drive centre´s were about 33". I have taken many measurements from the new engines and the centre´s should be about 37 3/4", allowing 4" between the engines. The TRS transom plates are bigger than the Alpha 1 plates but mostly vertically, the width is not much different. So, I need to move the drive holes about 2 1/2" outboard. Does this mean that I must replace the entire transom or can I build up the inner edge of the existing holes and open out the outer edge of the existing holes?

Either way, what´s the best way to do the job.

Pete

MOBILEMERCMAN
12-14-2010, 04:10 PM
You have your hands full.. I would think adding a center stringer is in order.. Have you measured the length required for TRS? It looks tight length wise to me. Have you considered Bravo's?

Any way my 10 Meter has 502's, Gil exhaust, TRS and 33" centers.

68123

MOBILEMERCMAN
12-14-2010, 04:26 PM
How wide are your engines with exhaust? That is the pressing question for choosing centers.

Senor Falcon
12-14-2010, 05:30 PM
Hi,

Manifolds are 33 3/4" wide and then the turbo over hangs nearly 1", but, the other engine, with the turbo facing the same way, is 1" inside the edge of the manifold. So, I have 33 3/4" wide. How close are those engines? Do you have anything to stop them hitting each other?

See photos

Pete

MOBILEMERCMAN
12-14-2010, 07:20 PM
Take the time to figure it out exactly.. It may be worth the time to set them next to each other on the pallets and square them up to see where they meet. If you select a rubber type mount you will need to allow clearance for the engine to move in the mounts.. If you are going with a plate type solid mount you can position them tighter. Once you confirm those dimensions you can lay out your transom.

MOBILEMERCMAN
12-14-2010, 07:59 PM
I have a TRS installation manual I scanned a few pages from.. I am having trouble uploading them for you..I will post as soon as I figure out the problem.

MOBILEMERCMAN
12-15-2010, 12:38 AM
I hope you find this helpful.

68130

68131

68132

I had to resize them to get them to load. If you double click on the image it will allow you to zoom some.

Senor Falcon
12-15-2010, 06:44 AM
Thanks Jim, everything you say makes sense. I agree with getting both engines side by side and will be working on that this week. When you say "plate" mountings, what are the "for and against" for using these mountings?

Those pictures are very helpful and if you could email them to me, they will probably be clearer when printed, if you don´t mind. Peter1961@hotmail.co.uk

If they are still wider than the existing, is it possible to move the drive holes an inch or two, by filling in one side (keyed into existing wood and fibreglass) or will I need to replace the entire transom?

Thanks again

Pete

MOBILEMERCMAN
12-15-2010, 10:11 AM
I have no experience with diesels and have no idea if they use the conventional mounting bolt patterns. If they are the same as the gas BBC or SBC these will work. 72514 is the port side and 72515 is stb. They work well and are widely used. They do however need stringers to accommodate them. Typically they bolt to the stringers with 1/2 aluminum angle. Once set up they become care free. The down side is they take much more time and effort to initially install them and properly align the engines. { in this case with the tight engine compartment it may be near impossible without an engine jig or dummy block }The stock type pedestal rubber mounted type{ that you appear to have already} allow the engine to be adjusted and aligned much easier. They do however allow the engine to move so more clearance is necessary. It will be much easier to use the latter.. The mounting provision you will need to fabricate wont need to be as exact since the mounts allow adjustment. The angle plates get installed to the stringers with the engine { or dummy block } hanging in position.

I checked the paper templates are still available.. Buy a pair of them and mock up the lay out and see how they overlap the existing holes.. My feeling is you will be filling the transom and adding a center stringer. Determine the centerline you are going to use. Layout the transom measure for mount placements and clearances.. It is going to be tight.

68134

HIGH LIFE
12-15-2010, 07:23 PM
Senor Falcon, I have a pair of front engine plates ( same of above specs ) if you need them . I live in Mass. Zip 02043 "HIGH LIFE"

MOBILEMERCMAN
12-15-2010, 08:32 PM
Pete, Take a look at http://www.seriousoffshore.com/forums/showthread.php?t=5054. Frank shared much info during his project which is similar to yours.

Below are some pix to show the different mounting configurations I was talking about.

http://www.seriousoffshore.com/forums/showthread.php?t=5054&page=7 post #125 to see what stringers for plate mounts looks like and page 3 post #52 for pedestal mounts.

Senor Falcon
12-16-2010, 07:07 AM
Thanks Jim,

I read the entire thread and was very interested. After reading many threads and many of them saying that the entire transom should be replaced. I feel sure that the only reason to replace all of it, would be if there was any bad wood or glass. In my mind, I was thinking to overlap 1/2 ply x 3 but it looks like 3/4 x 2 is sufficient. Is there a "correct" amount to overlap the joints? and would I need to fill the entire hole or just the inner edge, that´s too close to the centre line? I have also heard that soaking the ply with resin, without catalyst, before the full resin "with catalyst" is used to join them. Is this good practice? It also appears that I need to find a TRS jig, if this is such an impossible task, with a basic template?

By moving the drives outboard, I guess that I can keep the engines far enough apart and not need the offshore mounts? Maybe I should be looking at a centre stringer and the "pedestal mounts"? Making the engines more stable with the hull and not needing that huge "RSJ" style mounting beam?

Thanks for all your help Jim.

Pete

MOBILEMERCMAN
12-16-2010, 10:12 AM
I have used paper templates numerous times. They work just fine. The only thing the jig does the paper doesn't is it holds the drill at the correct angle.. You can do this your self if you pay attention and/or a friend assists. Lay out the transom before you make your final call as to how much needs to be filled..The holes will not only be moving out they will also be moving up. Make no assumptions as to where the holes will be .. Verify by laying it out in advance! The work is in the process. whether you add 4 inches or 8 doesn't change much.. Yes, I agree if the entire transom is sound just modify as needed. Never heard of soaking the wood. I would not suggest that. Use at least a 3" overlap. I think I would lean strongly toward removing the false floor and adding the center stringer. Either way take a good look at the outside stringers to ensure they are in good shape.

I think 1 1/2" minimum clearance between the engines would be good.. The turbo housings will not like bumping into each other under way

Senor Falcon
12-17-2010, 04:34 PM
Thanks Jim,

I´ll cover the holes with paper, get some work done on the measurements and then post pictures, to see what you think. Got work next week so not sure when I´ll get it done. If I don´t get back on before christmas, Happy Christmas to you all.:party:

Thanks again.

Pete

Senor Falcon
12-24-2010, 11:07 AM
Hi All, I got the rough template done today. It´s not mm perfect but when I transfer it to a stiffer card I will trim exact. I think it will help a lot, having the transom in the lounge (not what the other half said though)

Ok, a couple of questions;

1, Should the transom be exactly symmetrical?
2, If not, where should measurements be taken from?

I have taken a centre measurement, from the outside edges of the boat (close to top of transom), down to the centre of the lowest part of the hull. I think that the original drives were put in Pis*ed, as you can see. I am hoping that this is nothing like the "offset" for some outboard installations.

Next step is to make card template and cut exact, then plan new drive holes, based on cavitation plate (gear box) 1 to 2 inches above hull bottom.

Anyone have any ideas or observations?

Thanks

Pete

Senor Falcon
12-24-2010, 11:08 AM
2 more photos

MOBILEMERCMAN
12-24-2010, 01:20 PM
Ok, a couple of questions;

1, Should the transom be exactly symmetrical?
2, If not, where should measurements be taken from?


Anyone have any ideas or observations?

Thanks

Pete

1. It should be but, many are not.
2 Level the boat side to side. Measure from the corners and chines. Mark a high and low spot. You may need to adjust for inconsistencies. Once the boat is leveled side to side you can use a level to verify the vertical center line. Once you establish the vertical centerline that's what you will use for all measurements. You may find it is like finding the centerline of an egg. This can be nerve racking but, it is the most important step.

Have you determined what engine centerline you will use? The engines determine that.. Next with the template of the units you will be using lay them out using the centerlines you verified and adjust to the height needed. At that point you find what needs to be filled. When the time comes to actually drill you should mark the transom and measure directly on the boat IMO.

I think once I have determined for sure everything will fit inside I would fill fill every hole on the transom then prepare and paint it.

Happy Holidays,

Senor Falcon
12-27-2010, 06:07 AM
Thanks Jim,

Points 1, and 2, taken and I agree with what you say.

The centres are not fully decided as yet. Mainly because I am realising that the further outboard the drives are, the higher the engines will be, in the boat. I have also noticed that the TRS, drive shaft to prop shaft, is about 1"1/2 longer, lifting the engine that much higher also. Then, if that wasn't enough, I see that the TRS also stands back from the transom about 5"1/4 more than the Alpha 1. Is there a way to work out how much higher the drive shaft should be because of this setback?

I have found a setup sheet for the Apla / Bravo installation. This includes measurements for a right angle (90 degree tool) here http://www.boatfix.com/merc/Install/gas/86017211.pdf , it´s lined up with the drive centre line and level with the hull, at that point, then the top of the upright is the correct (cav plate level with hull) position for the horizontal centre line. Is there any measurements for this type of tool, for the TRS drives?

I´m going to spend some time getting the exact measurements but I think I have the general idea. It does look like I might have to raise the engine cover, although it might look a little strange with a 2 story aft end :-)

Pete

MOBILEMERCMAN
12-27-2010, 11:19 PM
Is there any measurements for this type of tool, for the TRS drives?



I provided you those dimensions on post # 35

Senor Falcon
12-28-2010, 05:02 AM
Hi Jim, I had forgotten that, sorry. Would it be possible to email them to me? Also, can you tell me where I can buy the templates from.

Thanks again.

Pete

MOBILEMERCMAN
12-28-2010, 09:56 AM
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