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Mercruiser 502 VS ZZ502

hemetdragracer

hemetdragracer

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Anyone ran a ZZ502 "car" engine in their boat? Heres my deal, My Mercruiser MPI 502 with a Whipple in my 26' DCB Mach 26' is hurt. At this point Im not sure if I should just fix/rebuild, or just replace it... What are my options? Can I buy a ZZ502 and bolt on the MPI stuff and my Whipple? Any suggestions or ideas? Looking for quickest, cheapest solution to get on the water...
 
BUSTI

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hemetdragracer said:
Anyone ran a ZZ502 "car" engine in their boat? Heres my deal, My Mercruiser MPI 502 with a Whipple in my 26' DCB Mach 26' is hurt. At this point Im not sure if I should just fix/rebuild, or just replace it... What are my options? Can I buy a ZZ502 and bolt on the MPI stuff and my Whipple? Any suggestions or ideas? Looking for quickest, cheapest solution to get on the water...
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This is the biggest problem you are going to have. If you try to put a cheap patch on it you will not be satisfied. If you are not looking for any major performance changes I would pull the motor and drop it off to a Teague, Pfaff, B&D and Obnoxious for a rebuild. Change the hurt parts and upgrade the parts that need some added strength so it doesn't get hurt again.

The ZZ502 is not marine ready. Boat engines have certain critical clearances that are ery specific for the high RPM and load boats see.
 
SBMech

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Engines built for marine use are quite different than engines built for automobiles.

Get your 502 fixed, you'll just break the ZZ trying to use it in your boat.
 
rivrrts429

rivrrts429

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I've seen crate motors that are less than pleasant to the eye when opened up.

I think there's a misconception that crate motors are sprinkled with pixie dust, they're not. Not to mention you won't find one from GM built for marine use. They all have a disclaimer saying otherwise.

It would live a little bit better in a closed cooling scenario with consistent water temps but it's likely you're going to have issues.

Have the motor built to the boats spec rather than making a car motor live in a marine environment.
 
Jmp

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You will end up spending more in the long run if you do not go with a marine engine. Pay now or pay a lot more later.
 
AzGeo

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IF you hook up with a reputable engine shop, it will be more cost effective to rebuild your old 502 with an Eagle stroker kit, than to purchase the crate motor .

The Eagle kit will make the motor bigger, and use much better parts along the way .

Consult a local engine expert, or ask Obnoxious (Barry) on here . PM him with what you have and what you want to end up with .

Boat motors see a much longer and more heavy load at higher RPMs . This is not a job for an 'engine re builder' ....
 
obnoxious001

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BUSTI said:
This is the biggest problem you are going to have. If you try to put a cheap patch on it you will not be satisfied. If you are not looking for any major performance changes I would pull the motor and drop it off to a Teague, Pfaff, B&D and Obnoxious for a rebuild. Change the hurt parts and upgrade the parts that need some added strength so it doesn't get hurt again.

The ZZ502 is not marine ready. Boat engines have certain critical clearances that are ery specific for the high RPM and load boats see.
Click to expand...

AzGeo said:
IF you hook up with a reputable engine shop, it will be more cost effective to rebuild your old 502 with an Eagle stroker kit, than to purchase the crate motor .

The Eagle kit will make the motor bigger, and use much better parts along the way .

Consult a local engine expert, or ask Obnoxious (Barry) on here . PM him with what you have and what you want to end up with .

Boat motors see a much longer and more heavy load at higher RPMs . This is not a job for an 'engine re builder' ....
Click to expand...

Thanks guys,, it probably does make the most sense to rebuild what you have versus the crate engine. It's possible the crate engine would run normally aspirated, but it probably should be opened up and clearances checked and changed if necessary. If I am not wrong, GM puts a disclaimer on their crate engines stating "not for marine use"

The Pfaff engine in CL is perhaps the quickest way to get back on the water at about the same cost as the crate engine?
 
hemetdragracer

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Thanks all, I know you guys are right... I just keep looking at Mercruiser remans, than see the ZZ with more HP, new, for the same money... I haven't tore it down yet, It had a cylinder hydrolock for unknown reasons, we put a camera in the cylinder and its pretty scored, Bad part is it was a Mercruiser reman, first time out. It has a 3 year warranty, however the whipple voids it. (even though it doesn't look like the whipple caused it) Im thinking it had problems from the get go...
 
SBMech

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You should try and warranty it, as long as there are no signs of it leaning out due to boost, you probably got one that was not "sprinkled with pixie dust".

Let them tear it down and look, never hurts to try. :D Take plenty of photos of what you can see, just to make sure it jives with what they say.
 
robby dmax

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hemetdragracer said:
Anyone ran a ZZ502 "car" engine in their boat? Heres my deal, My Mercruiser MPI 502 with a Whipple in my 26' DCB Mach 26' is hurt. At this point Im not sure if I should just fix/rebuild, or just replace it... What are my options? Can I buy a ZZ502 and bolt on the MPI stuff and my Whipple? Any suggestions or ideas? Looking for quickest, cheapest solution to get on the water...
Click to expand...
I have to say my buddy has had his zz502 in his boat for 6 or 7 years no problems. I believe all he changed was the cam went marine style and mls head gaskets.
On the mpi 502 all cast crank rods pistons.. I'm pretty sure the zz502 comes with all the forged stuff.
 
hemetdragracer

hemetdragracer

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SBMech said:
You should try and warranty it, as long as there are no signs of it leaning out due to boost, you probably got one that was not "sprinkled with pixie dust".

Let them tear it down and look, never hurts to try. :D Take plenty of photos of what you can see, just to make sure it jives with what they say.
Click to expand...

Know of any Mercruiser dealers that will take it??? The shop that installed it (Anglers Marine SD) says they no longer do Performance boats. Shit, I'd pay the labor if I could find a dealer to do it!
 
SBMech

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I don't actually, all my stuff I do myself. Maybe someone who knows of a good one near you can chime in.
 
Gelcoater

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obnoxious001 said:
If I am not wrong, GM puts a disclaimer on their crate engines stating "not for marine use"

?
Click to expand...
You're not wrong.

image.jpg
 
Runs2rch

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GM does not warranty for marine use as you guys stated. It does not mean that certain engines they build are not suitable. I know guys with zz383's, and zz4's in boats that have performed for many years without issue.
 
hemetdragracer

hemetdragracer

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Runs2rch said:
GM does not warranty for marine use as you guys stated. It does not mean that certain engines they build are not suitable. I know guys with zz383's, and zz4's in boats that have performed for many years without issue.
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Which is part of why I ask... I'm being told my warranty on my Mercruiser is void because of the Whipple too... So really warranty isn't a factor for me...
 
rivrrts429

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hemetdragracer said:
Which is part of why I ask... I'm being told my warranty on my Mercruiser is void because of the Whipple too... So really warranty isn't a factor for me...
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It's a beautiful boat. A DCB isn't a bayliner.

It's not my money so I'm out of place giving you my opinion but if you asked for advice I'd offer this...

That boat deserves to have a motor which equals it's brand. If for some crazy reason you needed to get out from underneath it most people are going to pass on the ZZ package.

I'd yank the current motor apart and figure out what you're working with first. Until then you just don't know. Factory power is desired and if you can equal it or improve it I would go that route. At the very least build a motor that will match and handle the whipple package.

You're boat is beautiful BTW. I'm sure whatever you choose will work out. Just spit balling ideas for you at this point.
 
Runs2rch

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hemetdragracer said:
Which is part of why I ask... I'm being told my warranty on my Mercruiser is void because of the Whipple too... So really warranty isn't a factor for me...
Click to expand...

I agree. Build a longblock that will compliment the BOOST!!!!
 
hemetdragracer

hemetdragracer

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rivrrts429 said:
It's a beautiful boat. A DCB isn't a bayliner.

It's not my money so I'm out of place giving you my opinion but if you asked for advice I'd offer this...

That boat deserves to have a motor which equals it's brand. If for some crazy reason you needed to get out from underneath it most people are going to pass on the ZZ package.

I'd yank the current motor apart and figure out what you're working with first. Until then you just don't know. Factory power is desired and if you can equal it or improve it I would go that route. At the very least build a motor that will match and handle the whipple package.

You're boat is beautiful BTW. I'm sure whatever you choose will work out. Just spit balling ideas for you at this point.
Click to expand...

Thanks... Just a Update... Its at Paul Pfaff Racing getting the engine rebuilt, along with a few upgrades to hopefully make it last with the Whipple... So far the customer service has been great, If all goes as planned I should have it out in a few weeks!!! Thanks everyone for the input!
 
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