Vortec 350 5.7 Mercruiser Build

Nextelbuddy

Petty Officer 2nd Class
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Very excited to be close to getting my the new engine finished and into the boat.

Brief recap is that my 1996 Sea Ray 210 blew the mercruiser 350 5.7 on cylinders two and four. (Lovely holes in the block trashed everything)

Coincidentally those are the same two cylinders that were crossed at the distributor cap from the previous owner that I found when doing maintenance and swap the distributor spark plug wires back to the proper locations but unfortunately I guess at that point it was too late and the damage had been done engine go boom.

Fond a 1997 k1500 in South Carolina went and pulled the vortec engine out of that brought it home, stored in my garage for a few months and when I was getting ready at a friend's house I dropped it off the cherry picker onto the concrete pad bending the snout on the crank.

Dropped the engine off at the engine builder check the tolerances confirm that the cranks now was out of round and out of spec but even if it wasn't bent there was some hidden surprises that the previous owner of that engine didn't tell me and that was that they froze the block by running water in the winter time and there were four cracks in the water jackets on that engine that were hidden by rust and debris.

So ended up just salvaging the vortex heads off of that engine and sourcing a third 350 5.7 short block


So with all that out of the way, lots of money spent sourcing parts... This is what we have now...my humpty Dumpty 350 5.7 😂

Bare Block and heads were hot tanked 6 times at request of engine builder..(I guess he likes his blocks and heads squeaky clean), Block was honed and decked

Excited that the gentleman building the engine is one of the lead mechanic/engineers for a panos race team

Don't pay any attention to the picture with the serpentine crank pulley it has the incorrect one he just used it as a placeholder until I gave him the proper V belt mercruiser crank pulley today.

Engine upgrades
- Vortec block and heads
- new brass freeze plugs
- COMP Cams Xtreme Marine 08-416-8 Camshaft
- comp cam springs with new stock retainers and locks
- new roller lifters
- all 8 pistons had oil relief holes machined near oil ring seat area (builder says it's a common oil/heat failure point on these engines in regards to proper oiling)
- new piston ring set cut and filed to engine builder specs
- new oil pump
- new rod bearings and main bearings
- polished crank shaft
- balanced rotating assembly (crank, rods, pistons)
- summit racing dual plane intake manifold
- Edelbrock 1409 marine carb
- Quicksilver distributor cap/rotor/plug wires
- AC MR43LTS spark plugs
- felpro marine head gaskets
- felpro oil pan gasket and rear main seal
- Felpro valve cover gaskets
- mercruiser thermostat
- Carter electric fuel pump conversion with oil switch and starter safety system
- Edelbrock bronze distributor gear for vortec roller cam
- new mercruiser engine coupler
- all new mercruiser nuts and bolts for engine mounts, bellhousing and transom plate
- new exhaust manifold gaskets and riser gaskets

Out drive upgrades
- water impeller kit
- input shaft seal carrier assembly
- shift shaft carrier assembly
- pressure tested outdrive 12psi for 20 min no pressure loss (mercruiser tech states 10psi for 10 min is acceptable)
Boat upgrade
- new airmar b19 thru Hull transducer and lowrance 3800 depth sounder system
- reinstalled new mercruiser alarm system for low oil pressure/over heat/drive oil (previous owner cut alarm out 🤬)


I hope this boat runs well when it's done.


PXL_20210701_221708135.jpgPXL_20210701_220158411.jpgPXL_20210701_220212445.jpgPXL_20210701_220148716.jpg
PXL_20210701_221658706-01.jpeg
 

Nextelbuddy

Petty Officer 2nd Class
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May 4, 2020
Messages
156
thanks guys!, yea my engine never had a remote oil filter setup, i've changed oil twice while in the boat and learned quickly not to over tighten the oil filter so that "future me" doesn't cuss out "past me" its not terrible but not the greatest to change.
 

Alumarine

Captain
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Feb 22, 2005
Messages
3,695
thanks guys!, yea my engine never had a remote oil filter setup, i've changed oil twice while in the boat and learned quickly not to over tighten the oil filter so that "future me" doesn't cuss out "past me" its not terrible but not the greatest to change.
I always put grip tape on my boat and car oil filters as often there isn't enough room to get a wrench on them.
Stole that idea from Fram.
 

Nextelbuddy

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May 4, 2020
Messages
156
Looks good
Assume you can get to the oil filter easy when installed
Curious on something in regards to max rpms with this new setup.

i usually follow this guide for specific type of engine and max RPMs.


i tried to replicate a Mercruiser type build with this engine, what Max RPMs would you feel comfortable with this engine? 4800? 5000? 5500? or just take it out and see what it does?


my engine builder is going to come out when I have the engine ready to go and hes going to set the Timing for me with a timing light, should I follow the recommended base timing of 10 degress BTDC as indicated on the flame arrestor? or should i let my engine builder set the timing to what he feels is adequate to his liking?
 

alldodge

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Max rpms is dependent on internals used, and how those are balanced. Your cam list 1000-5000 rpms and I haven't seen where the pistons, rods, crank is anymore then stock. I would set it to 10*BTDC and see how it does.

That said, your build may be an expert or just a good builder. See what he says

Maybe @Scott Danforth can add some
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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What did your builder balance the assembly to? Zero?

What are the bearing clearances for rods and mains? Did you go with coated bearings?

Stock pistons, or hypers or forged? Flat tops? D-dish?

Cast or forged crank? Cast rods, or H-beams? Cast or billet flywheel? Stock damper or sfi 1.1 damper?

Compression ratio?

Stock oil pump, melling? Stock PRV spring?

That is what determines the RPM you run at.

If you are running a good oil pump, cast pistons, rods and crank, zero balance, and .002 clearance with coated bearings you can spin to 5500 RPM without concern (also the limit of the drive)

If you are running forged internals, high volume oil pump, zero balance and sfi rated flywheel and damper, you can spin it until you get valve float
 

Nextelbuddy

Petty Officer 2nd Class
Joined
May 4, 2020
Messages
156
What did your builder balance the assembly to? Zero?

What are the bearing clearances for rods and mains? Did you go with coated bearings?

Stock pistons, or hypers or forged? Flat tops? D-dish?

Cast or forged crank? Cast rods, or H-beams? Cast or billet flywheel? Stock damper or sfi 1.1 damper?

Compression ratio?

Stock oil pump, melling? Stock PRV spring?

That is what determines the RPM you run at.

If you are running a good oil pump, cast pistons, rods and crank, zero balance, and .002 clearance with coated bearings you can spin to 5500 RPM without concern (also the limit of the drive)

If you are running forged internals, high volume oil pump, zero balance and sfi rated flywheel and damper, you can spin it until you get valve float
great info thank you very much.



what about spark plug gap?

using AC MR43LTS

the pistons are stock pistons as the block pistons and rods are from a non vortec engine with vortec cylinder heads.

would i still go with the .035 gap from my olf non vortec engine or with the newer .045 on the mag/mpi engines?

my ignition system is still thunderbolt V i believe but maybe you can judge based on this picture?

looks like this is an ICM module but dont see a knock module anywhere.

PXL_20210712_002344753.jpg
 

Nextelbuddy

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That is a t bolt 4 module.

Run a .045 gap on the plugs
so doing some more research so i can better educate myself on ignition identification. i still dont quite understand hw looking at this easily identifies it as thunderbolt IV.

i have yet to find a good picture showing a thunderbolt 5...

all i can find are diagrams drawings that show thunderbolt 5 with a knock module attached to it but then other places indicate that not ALL thunderbolt V have knock detection modules.. so i can not find a pic of what thunderbolt V looks like in real life.

when i search for my part# 807264-2 or by my engine serial 0F760044 , i find this page


which shows module 26 but several iterations. none of them are exact match to 807264-2 and the closest one i find is 807264A01 but there are 2 iterations of it as well and even then its been superseded by a newer module with an adapter harness.....

the main reason why i want to e absolutely sure is that i see on thunderbolt IV you dont set base timing mode by grounding the purple/white wire but on thunderbolt V you DO ground the purple/white wire.

i have a purple/white wire with a rubber plug in it but if i have thunderbolt IV then what is that wire for if we are not supposed to ground it to set base timing?

why is it so difficult to get concrete ignition identification in online reference materials these days? even parts diagrams dont tell you thunderbolt IV or V they just give you part#s only. why wouldnt they? thats a mercruiser term so its not like its a slang term people made up so theres no reason not to reference it in their service material and parts diagrams.
 

Scott06

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so doing some more research so i can better educate myself on ignition identification. i still dont quite understand hw looking at this easily identifies it as thunderbolt IV.

i have yet to find a good picture showing a thunderbolt 5...

all i can find are diagrams drawings that show thunderbolt 5 with a knock module attached to it but then other places indicate that not ALL thunderbolt V have knock detection modules.. so i can not find a pic of what thunderbolt V looks like in real life.

when i search for my part# 807264-2 or by my engine serial 0F760044 , i find this page


which shows module 26 but several iterations. none of them are exact match to 807264-2 and the closest one i find is 807264A01 but there are 2 iterations of it as well and even then its been superseded by a newer module with an adapter harness.....

the main reason why i want to e absolutely sure is that i see on thunderbolt IV you dont set base timing mode by grounding the purple/white wire but on thunderbolt V you DO ground the purple/white wire.

i have a purple/white wire with a rubber plug in it but if i have thunderbolt IV then what is that wire for if we are not supposed to ground it to set base timing?

why is it so difficult to get concrete ignition identification in online reference materials these days? even parts diagrams dont tell you thunderbolt IV or V they just give you part#s only. why wouldnt they? thats a mercruiser term so its not like its a slang term people made up so theres no reason not to reference it in their service material and parts diagrams.
I was under the impression that all TB Vs looked liek this


If you have a white and purple wire you may have a TBV then , try grounding it start the engine and see what happens to timing with a timing light. SHould be locked when grounded and be moving around a little when not in base mode.

Not all TB Vs have knock sensors. I think most base 2 bbl engines like the 4.3 and 5.0s Ive had do not have knock control
 

Nextelbuddy

Petty Officer 2nd Class
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In the stickys there is a TB thread showing both. But for easy reference see like and note the TB4 (item 7) is not square and its skinny

https://www.mercruiserparts.com/bam/subassembly/31835/1014/90
yes ive seen that before


you actually linked that thread when i asked this questions in a specific topic last year. you said I had a thunderbolt IV just looking at my pic i posted

photo338964.jpg

then i asked how you knew that was thunderbolt V just looking at it and you said "Without looking up the part numbers, I saw the knock module."

in that pic i dont see a knock module. I see the ICM or ignition module right below the bare plug stud on the dizzy.

that's module 26 when i look at the diagram for my engine based on serial

which is this module i took a pic of last night that has part# 807264-2 which has been supersceded by part# 807264A01 which looks very similar to a thunderbolt V module i have seen online.


PXL_20210712_002344753.jpg

but i dont see a knock module anywhere.

so i just want to make sure i stop confusing myself even further, many apologies if it seems i'm going around in circles.

i dont want to make assumptions and i want to tell myself that the simple fact that I have a purple/white wire with a rubber plug means that i use that to set base timing and its a thunderbolt V.. unless someone else tells me yes they have seen thunderbolt IV with the purple/white wire despite not using it to set base timing.
 

alldodge

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Part number 807264 is a TB5, and as Scott said not all have the knock module

807264A01 old 806975T4 5.7LX
 

Nextelbuddy

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May 4, 2020
Messages
156
I was under the impression that all TB Vs looked liek this


If you have a white and purple wire you may have a TBV then , try grounding it start the engine and see what happens to timing with a timing light. SHould be locked when grounded and be moving around a little when not in base mode.

Not all TB Vs have knock sensors. I think most base 2 bbl engines like the 4.3 and 5.0s Ive had do not have knock control
I do indeed have a purple wire with white stripe that has a rubber plug in it and my engine is a mercruiser 5.7LX that originally came with a 2BBL carb. carb was changed to rochester 4 BBL Manual choke carb. I blew engine and replaced with a vortec 5.7 and marine 1409 electric choke carb and just want to make sure i know which ignition system i have so i can set base timing or timing in general for my first start up. Its not currently in the boat yet but getting all my ducks in a row
 

Nextelbuddy

Petty Officer 2nd Class
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Messages
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Part number 807264 is a TB5, and as Scott said not all have the knock module

807264A01 old 806975T4 5.7LX
thanks Dodge and Scott, its just hard for my brain to comprehend sometimes why you can have situations where older engines like mine which is 1996 will have thunderbolt V which is newer but then have newer boats from 1998 o 2000 or even 2004 i've seen that have thunderbolt IV still.

so since i have thunderbolt V that means i will have to use the purple/white wire grounded to set base timing mode first and then after that have an understanding that the thunderbolt V has a RPM limit vs IV which has no RPM limit.
 
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