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Gunsbuns

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I'm a newb so go easy on my lack of knowledge :)

I have a 2005 Monterey 194fs with the 5.0 GXI VP engine. About 200hrs and used in salt water but flushed regularly. It was running fine when last used but wouldn't start after a 6month hiatus (trailered). Mechanic found corrosion in some cylinders and suspects salt water has got in through the exhaust manifolds (?) when last used which has resulted in the rings rusting and locking up the engine. Couldn't even turn it by hand with spark plugs out using a socket and pole.

So choices are rebuild the existing 5.0 - he says $6-8k (we're in Australia) or repower with something else. As I use it exclusively in salt water, I'd like to go fresh water cooling to improve longevity.

A bit more power would be nice so was thinking a 5.7??

obvious options are the VP 5.7 or a mercruiser 5.7. - but can you mate a mercruiser to a VP leg?

If yes, which would be a better option ?

any ideas on potential US importing options as they seem prohibitively expensive here (eg, a 'new' Vp 5.7 is being sold on eBay here for $14999 starting bid!)

many thanks
 
Could be wrong but.
I believe all GM based 5.7 are the same and i would think most if not all the necessary parts like flywheel, exhaust, oil pan and such would transfer over from your 5.0 but i would also research it further.
You could go as far as finding a car 5.7 that needs rebuilt for cheap.
Then have a reputable Automotive machine shop rebuild it to MARINE standards with the proper Camshaft, Freeze plugs, Gaskets and what ever else it needs.
In the US this is easy stuff and under 2K if you do a lot of the work your self but i have no idea about Australia and assuming all your 5.0 stuff interchanges.
 
First and foremost..... find out where the water is coming from that caused rust at the cylinders/piston rings.

Also..... when laying up for the winter, find a safe method for doing a quick dry start as to blow the exhaust system dry.
Volvo Penta has NEVER used a drive located seawater pump, so usually the seawater pump lends itself to being disabled easily.
8 to 10 second low speed dry start without water can be done safely.

I've been doing this for longer than I can remember.
It does work.


As for over-hauling, if you can find a shop who is willing, avoid going back together with the GM full dished piston.
http://www.marineengine.com/boat-forum/showthread.php?394668-V6-to-V8-engine-swap (start at post #7)
 

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Your 5.0 GXI VP is an MPI engine. You are better to replace it with a 5.0 ltr engine. It's only a 19 foot boat. The fuel curve will be too lean if you go to a 5.7LTR. The flywheel and balancer are different between the 5.0 and the 5.7.


You can purchase a 5.0 Mercruiser long block and dress it with all the VP parts. I would purchase my engine from Mercruiser and not have one built. The warranty is excellent.

In the Mercruiser world, if I convert a raw water MPI engine to a FWC engine, I send the PCM back for a reflash for the higher running temps, not sure about the VP's.
 
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Gunsbuns said:
So choices are rebuild the existing 5.0 - he says $6-8k (we're in Australia)
I can understand that parts may be more expensive in Australia..... let's say 200% more expensive.
Minus the additional parts cost, what then explains the $6-8k when here in the states we can over-haul this same engine for approx $2.2K.... and perhaps $2.4K with the correct pistons?
I'm just curious!

As I use it exclusively in salt water, I'd like to go fresh water cooling to improve longevity.
Going with a Closed Cooling System will definitely be a benefit.

A bit more power would be nice so was thinking a 5.7??
Chris makes a good point about the fuel metering.

obvious options are the VP 5.7 or a mercruiser 5.7. - but can you mate a mercruiser to a VP leg?
If yes, which would be a better option ?
These are basically the same SBC based engine.
Click to expand...

BTW, if you do go with a Closed Cooling System, you could use a cooler thermostat to circumvent sending the PCM back for a reflash for the higher running temps.... although the engine will prefer the higher temperature.

BTW #2..... I would not over-haul a previously raw water cooled engine that has routinely seen salt water.
Salt water rust/corrosion follows no prescribed path..... the degree of corrosion damage is unpredictable.



.
 
RicardoMarine said:
BTW, if you do go with a Closed Cooling System, you could use a cooler thermostat to circumvent sending the PCM back for a reflash for the higher running temps.... although the engine will prefer the higher temperature.

BTW #2..... I would not over-haul a previously raw water cooled engine that has routinely seen salt water.
Salt water rust/corrosion follows no prescribed path..... the degree of corrosion damage is unpredictable.



.
Click to expand...


Thanks Rick and Chris - good info.
1. Rebuild price: Yeah, I was a bit skeptical as well. Things marine here are quite a bit more expensive than the US but I was taken aback when he suggested this type of cost. He said he'd 'need to rebuild' it but my first thought was that surely I could get a new engine for that - or not much more. He says he's a 'marine engineer' and a VP dealer for 30 years but when he offered to buy my boat for $5k, I thought I was being conned. Who knows.

2. 5.0 Vs 5.7 : I agree that the 5.0 is fine for just running around but most of the work is pulling the kids around a lake on skis, tubes, wakeboards and everyone wants to be in the boat and I found it did struggle a bit to pull a 200lb guy on a single ski up while loaded. Just thought the 5.7 would manage this easier and was interested in how it might slot in and if the VP or Merc was best with the existing VP leg. Merc's seem to be easier to come by here in Aus but if it needs a whole lot of adaptation then maybe the VP is better. What does 'fuel metering' mean?

3. Rebuild: On reflection, I think you're probably right Ric. Who knows what the inside looks like in terms of corrosion. Interestingly it originally came from the US - I'm the second owner and I think the first owner brought it in when the Aus $ was really high compared to the US $.Is there a lake something in California? There's a rego sticker that ha sthat on the side.

Thanks again for sharing your knowledge.
 
Me in blue text.

Gunsbuns said:
Thanks Rick and Chris - good info.
1. Rebuild price: Yeah, I was a bit skeptical as well. Things marine here are quite a bit more expensive than the US but I was taken aback when he suggested this type of cost. He said he'd 'need to rebuild' it but my first thought was that surely I could get a new engine for that - or not much more. He says he's a 'marine engineer' and a VP dealer for 30 years but when he offered to buy my boat for $5k, I thought I was being conned. Who knows.
I'm going to be bold here and say that no one in their right mind would attempt to over-haul a previously Raw Water Cooled Salt Water engine!
I would question his credentials.

2. 5.0 Vs 5.7 : I agree that the 5.0 is fine for just running around but most of the work is pulling the kids around a lake on skis, tubes, wakeboards and everyone wants to be in the boat and I found it did struggle a bit to pull a 200lb guy on a single ski up while loaded. Just thought the 5.7 would manage this easier and was interested in how it might slot in and if the VP or Merc was best with the existing VP leg. Merc's seem to be easier to come by here in Aus but if it needs a whole lot of adaptation then maybe the VP is better.
As said, either is a GM SBC based engine.

What does 'fuel metering' mean?
This has to do with the fuel/air ratio. Your MPI is currently set up for a 5.0L. If you were to make the change from a 5.0L to a 5.7L, as Chris said it may be too lean. If too lean, it would certainly cause an issue.

Chris would be able to suggest what all would be involved to make the change.

3. Rebuild: On reflection, I think you're probably right Rick. Who knows what the inside looks like in terms of corrosion.
It would be a "crap shoot" in my opinion. Not worth it!

Have you looked at what MichiganMotorz has to offer?
Perhaps see if they will ship to Australia.
Click to expand...

http://www.michiganmotorz.com/marine-engines-remanufactured-marine-engines-c-31_51.html

Here's a reman 5.0L Vortec in long block form for $2,300 US.
50L001LG_170_138.jpg



Here's a reman 5.7L Vortec in long block form for the same price.
5_7reman001LG_153_140.gif



.
 
I have to disagree with one thing. A ten year old engine block used in salt water is totally rebuildable. A 19 foot boat that came from California, it's a pretty good bet that it was used on a lake. A salt water block here in New Jersey will last about 25 years. If in doubt, knock out a core plug and take a look.

If you plan on keeping this boat for more than 10-15 years and are going to run it strictly in salt water, by all means FWC the engine. If not, don't waste your money.

Now onto the important stuff. If you have a 5.0 in a 19' boat and you are using it for skiing and tubing, it may be better to leave it as a 5.0(because of the Fuel Injection) and just under prop the boat for this use. If you are going out for a cruise, change the prop back. Easy enough and cheaper.

I have two sets of props for our boat. If I have a lot of people on our boat I lower the pitch by 2 inches and all is good. A little higher rpm for cruise is ok as long ans the engine is not over loaded.
 
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