entire engine and drive swap

[Don S]

Re: entire engine and drive swap

You would be a lot better off than with the 470, that's for sure.
99% of the 305 parts will fit on the 350

 

[Bondo]

Re: entire engine and drive swap

Ayuh,.....

Now you're starting to make Cents.................

 

[Haut Medoc]

Re: entire engine and drive swap

I have decided to start parting out my 470 on ebay and start looking for a marine v8 and outdrive. So there is a big diff between a 305 and a 350. What if i was to buy a compleate 228 marine 305 that runs with a cracked block leaking outwards and move the marine stuff from it onto a good automotive 350 where would i be then? my drive is in really good shape but i guess i need to sell it to get the v8 gear ratio then?

Yes, either you will need to replace the upper gears, (not recomended for someone unfamiliar with the process), or sell yours, get a good buck & get a different one or a new SEI aftermarket for like $1200 off ebay....
Keep in mind that the lower half of your present unit is usable with a new upper as well, as long as you do not have the preload pin......

 

[travis.email]

Re: entire engine and drive swap

I bought a grab bag locked up 2004 5.0 MPI setup with the everything still on it. I am starting to get a little more excited about spending money on this now that its going to be fuel injected and at least look like it was expensive.

Does anyone know what happens if you put 350 inches where there used to be 305 on a mercury MPI setup? Would it make more then the 260 hp or/and would it ended up running lean? I have a spare megasqurt setup but i would rather just stay with the factory mercruser ecm that comes on the motor. I won't see my motor or boat in person for three weeks so its killing me. All i can to do for now is part out my 470. I am not sure if i have a Preload pin or not. If i get the serial number off it can i tell or is it a random thing. I might just sell it whole and buy the upper and lower SEI unit then.

I talked to the mech that pulled the 5.0 MPI he had no real interest in the sale of the motor to me. He said the customer was all for the new unit with a warrenty and had no interest in even letting him take a head off to see what happend. The story was that the motor was fine and then 2 months latter when the customer tired to use it again it would budge. I paid $850, a little over what mercruser was offering to get it back from them. They set it aside for me to pick up when i get my boat. I used to work at a ATV dealership so i know what kind of damage water could have done just sitting there.

 

[krisnowicki]

Re: entire engine and drive swap

travis email are you in jacksonville.. I saw that same engine in the shop I bought my repower from 3 weeks ago. The guy you bought it from if the same is a good guy and he will probably have a couple drives for sale too...

 

[HT32BSX115]

Re: entire engine and drive swap

Travis,

That engine will be a GREAT choice for your boat!

It may be a complete overhaul but it will be worth it! I really wish I could have found an MPI instead of a carb'ed engine!


If it was locked up after a very short time it could be a lot of things from blown head gasket to a leaking riser gasket or cracked riser/manifold.

At the least pull the plugs and see if you can turn the engine over.

A couple of weeks of water in the engine might result in a complete rebuild but you probably won't have lower end damage.

If you cannot find a good deal on a local drive, you can always get the transom "stuff" on ebay and an SE drive for it.

That engine is rated 250-280 hp. It should be pretty nice.

Yes you might be able to go to a 350 block but the cam, and ECM might be different. To get the rated HP out of a 5.7 MPI you would want to do everything Mercruiser does to get it to be a 5.7 MPI. that might be cost prohibitive and might not be worth it.

Don or someone else here can tell you exactly what you need to change it. Again the difference between a 5.0 and a 5.7 MPI in your boat is not going to make a lot of difference in performance.

Just make sure you get the correct ratio drive. Don't exclude yourself from getting a Bravo either if you find a super deal (like I did!) If the engine doesn't have the raw water pump it can be added easily. There's always a couple of surpentine belt raw water pump assy's (pump/bracket/pully) on ebay.

Sounds like a fun project. Don't forget to ensure that the transom wood is dry and sealed up good. I even did a little fiberglass work to clean up my engine compartment and painted the whole area with Bilge Kote to clean it up.

There's an enormous breath of freedom when you pull a Cobra out and put something MUCH newer in I'll bet it's the same when you pull a 470!!!



Cheers,

Rick

 

[travis.email]

Re: entire engine and drive swap

travis email are you in jacksonville.. I saw that same engine in the shop I bought my repower from 3 weeks ago. The guy you bought it from if the same is a good guy and he will probably have a couple drives for sale too...

Yeah I bet its the same guy then. I'm from Missouri but the motor is in jacksonville. I have decided to leave thursday to pick up the motor and boat down in florida. I have my eye on a alpha one leg and a transom assy that someone already blocked off the water pump on for me. I think the prop that comes on it might even work for the time being. It adds up to 48 mph at 4800 with 1.5 ratio?

Since the list of stuff that i was planning on using from my old boat has gone down to almost nothing. I am going to either put the replacement flywheel, cam, and water pump seal in it or selling it whole with the parts for then next person to fix it. Its a 1979 but it looks somewhat newer it had some gel coat added at some point in its life and they replaced the dog box with a newer style bench seat and engine cover with gas struts. I could still start it for someone that buys it to hear it run with the flywheel thats in it only that if it lands in the dead spot I have to turn it past it with a breaker bar. The way they cut off the bad teeth it dosen't even really grind its kind of a off on thing. Last season when i was using it 1 out of 4 starts you had to turn the crank. The starter drive still looks like new. The boat and the trailer both have good titles. Wonder what i might be able to get out of something like this. I was going to feel bad about parting it out just to keep the trim pump, trim cylinders and half the drive.

 

[96lt4c4]

Re: entire engine and drive swap

Ayuh,....

I Doubt a couple 4X8 sheets of Plywood would even be Big enough........

100+hp in a 20' boat is a Major Difference..........

I just had to say, thats funny LOL

 

[travis.email]

Re: entire engine and drive swap

I went down to Florida this past weekend and picked up the celebrity and the 5.0 mpi. The guy that had the motor sold me a y pipe and a trim pump for it. Before i left i won a alpha one transom assy and 1.5 ratio drive unit off ebay for about $550 i still have to go pick it up close to chicago, but i can get it with my 40mpg toyota yaris. I took the heads off the motor last night and got it on the engine stand the manifold was cracked on one side and leaked water in the cylinders but someone must have added something to the water early on because it didn't really rust that bad. I took the pan off too there is no rust to speak of in the lower end just some above the pistons. on the one side. Below the pistons the cylinder walls are like new you can still see the honeing marks. so i don't think it ever actully ran or cranked with water in it just sat, leaked, rusted, and got replaced. I soaked the cylinders down with penatration oil. I am going to remove the crank and try to tap the pistons out tonight. There is a machine shop here that will clean it and check for cracks for $50 and bore for $12 a hole. Unless something goes bad wrong removing the pistons i don't think i would need to go more then .030 over. What should i use for pistons? Autozone has pistons for a 1997 chevy 1500 van with a 305 for $26 each up to .060 over. Would this be too cheap? I can't find any happy middle ground.

 

[travis.email]

Re: How to interrupt a 2004 Bravo MPI 5.0

Re: How to interrupt a 2004 Bravo MPI 5.0

I have just started to worry about how to interupt the 2004 mpi Bravo to use with my Alpha drive. I have a interupt switch plate and everything from a alpha drive but i am wondering whats the best way to cause the mpi to cut out. The only idea i have so far is to use a relay to disconect the coil from the ECU when the interupt switch is closed. I am wondering if this would cause any negative side effects as far as error codes or ecm damage. Is it supposed to cut the whole engine like this would or only make it miss out.

 

[Don S]

Re: How to interrupt a 2004 Bravo MPI 5.0

Re: How to interrupt a 2004 Bravo MPI 5.0

What is the Serial number on the engine. (tag above starter)
You can't just start sticking relays in. The distributor doesn't do anything but distribute spark. There are wiring changes and ECM changes. But without a SN, it's hard to say what all you have to change.

 

[travis.email]

Re: entire engine and drive swap

My Block is at the machine shop being bored but i looked at my ECM its a

5.0 L Bravo
ECM 501
11-05-2004
666191-001

I think i might be on the right track I found a ECM diag manual #36 for a newer model 555 ECM. It showed me how my harness now has an A TO C jumper For Bravo pluged into a interrupt harness. For Alpha It shows using a 10k resistor from B TO C Then A TO C normally closed but Opens only to interrupt. Would my 501 ECU be the same is the BIG question now then i guess?

Would you still need my block number? It should be done soon. This number was on a sticker that said 5.0 l bravo on the
bellhouseing: WQ001FI1 and 4M42027TT

 

[Don S]

Re: entire engine and drive swap

Need the SN, Merc doesn't do anything by year, only SN range.

 

[travis.email]

Re: entire engine and drive swap

My motor is in the 0W316000 range. I also have a new question what is the best way to go about buying and installing a water pick up to feed the belt drive raw water pump? How big does it need to be where is the best place to put it ect... Do i need a shut off on it? Thanks for your help.

 

[travis.email]

Re: entire engine and drive swap

I was able to get the engine interrupt on the 2005 Bravo MPI to work great by using a normally closed relay to OPEN the two control wires that go from the coil driver to the coil when the switch is operated. Both control wires were doing the same thing so i was able to use one relay to open them both.
I found the windshield for it on ebay in NH for $99. But i had to pick it up myself lol.

Other then getting a prop that will work better with this boat I am all set now. I have taken it out 5 times now. It doesn't have a speedo working but i am going to take the gps along next time i take it out. It has a 19 pitch 3 blade alum prop that came with the out drive. That works OK with 2 people in it but with 6 in it this weekend it wouldn't get on plane right away and had trouble turning. Is it possible to have trouble getting on plane from having to low of pitch prop? After its on plane it will keep going faster untill it over revs if you don't let out of it. When it was loaded this weekend the easiest way to get it on plane was to run it up to 2800 or so and just wait for it to come up. If you ran it past 2800 before getting on plane it seem to take longer for it to come up. not sure if this would mean anything to you guys or not but i am open to suggestions. I would be happy to give up top end to get one plane quicker. I was only told the prop that was on it was 19 pitch buy the person on ebay that sold me the drive. Its a little be rough on the edges and had some pitting already when i got it. What all do i need to do with this prop on the boat and the gps to have a good idea of what prop i want to go to next.

Thanks for yout time.

Travis

 

[bruceb58]

Re: entire engine and drive swap

Your statement about not being able to run the engine over 2800 RPMs or it will actually take longer to get on plane suggests that either the prop hub is slipping or you are getting ventilation. I would start with a clean prop before doing anything else.

 

[Gerry1807]

Re: entire engine and drive swap

I have changed the starter gear on the flywheel just a little heat and a little freeze
new gear works better

 

[Gerry1807]

Re: entire engine and drive swap

What do you no about changing the cast iron head on the 470 mercruser
for a ford same series 460 /429 aluminum racing head I can get cheep will it
work and would the weight advantage be worth it I have a pair of 470s
in a 266 sea ray any help appreciated

 

[Don S]

Re: entire engine and drive swap

Gerry1807
Best to start a new thread with your questions, or your post will be at the end of a 2 year old post of someone elses and will never be seen.