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Repower Options
I posted yesterday about my issue with water in the oil. I haven't given up hope just yet but I am considering that its very possible I have a cracked cylinder. In the tradition of bench racing and considering it's winter time so I have a few months to figure out where to go I'll open this topic? If my 96 GenVI 7.4L Mag is toast what are my 'reasonable' cost options?
A) Replace the block and rebuild. Stay 4" stroke or go 4.25". Keep the original heads (assuming they aren't the problem). B) Replace the shortblock entirely. There are quite a few brand new Dart 540 shortblocks on the market for just over $4k. Will the stock rect port heads and MPI support a 540? What cam? C) There are a couple of brand new GM NOS Marine 502 Mag long blocks out there for about $7k. D) My mechanic wants to jump right to the brand new fully dressed 8.1L Vortec. That might bust the budget. Any other ideas for E), F) and G)? The boat is a 96 Formula 252LS. Its a heavy boat and I'm not looking for absolute maximum speed but fast cruising and occasional wake boarding are typical. The 7.4L was adequate but why not add HP when the checkbook is on the table? |
Not sure I'd let your mechanic do anything. He put 15 gallons of antifreeze into the engine before he noticed a problem.
Engine blocks don't just crack for no reason. Did it freeze hard before you took it in to be winterized???? or did the engine overheat recently???? I would just buy the fresh 502mpi in the swap shop or a low hour stock takeout engine. |
Originally Posted by mausc
(Post 3257913)
I posted yesterday about my issue with water in the oil. I haven't given up hope just yet but I am considering that its very possible I have a cracked cylinder. In the tradition of bench racing and considering it's winter time so I have a few months to figure out where to go I'll open this topic? If my 96 GenVI 7.4L Mag is toast what are my 'reasonable' cost options?
A) Replace the block and rebuild. Stay 4" stroke or go 4.25". Keep the original heads (assuming they aren't the problem). B) Replace the shortblock entirely. There are quite a few brand new Dart 540 shortblocks on the market for just over $4k. Will the stock rect port heads and MPI support a 540? What cam? C) There are a couple of brand new GM NOS Marine 502 Mag long blocks out there for about $7k. D) My mechanic wants to jump right to the brand new fully dressed 8.1L Vortec. That might bust the budget. Any other ideas for E), F) and G)? The boat is a 96 Formula 252LS. Its a heavy boat and I'm not looking for absolute maximum speed but fast cruising and occasional wake boarding are typical. The 7.4L was adequate but why not add HP when the checkbook is on the table? |
Originally Posted by ShadBurke
(Post 3258102)
There is some nice Ilmor 625hp gently used product out there in the marketplace right now that can be had for the $12-$15k range. Most of the product has around 100 hours freshwater use. Not sure how that fits into the budget or blows it......
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Originally Posted by Baja_man
(Post 3258112)
Any links to these?
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Originally Posted by Baja_man
(Post 3258112)
Any links to these?
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Originally Posted by mausc
(Post 3257913)
I posted yesterday about my issue with water in the oil. I haven't given up hope just yet but I am considering that its very possible I have a cracked cylinder. In the tradition of bench racing and considering it's winter time so I have a few months to figure out where to go I'll open this topic? If my 96 GenVI 7.4L Mag is toast what are my 'reasonable' cost options?
A) Replace the block and rebuild. Stay 4" stroke or go 4.25". Keep the original heads (assuming they aren't the problem). B) Replace the shortblock entirely. There are quite a few brand new Dart 540 shortblocks on the market for just over $4k. Will the stock rect port heads and MPI support a 540? What cam? C) There are a couple of brand new GM NOS Marine 502 Mag long blocks out there for about $7k. D) My mechanic wants to jump right to the brand new fully dressed 8.1L Vortec. That might bust the budget. Any other ideas for E), F) and G)? The boat is a 96 Formula 252LS. Its a heavy boat and I'm not looking for absolute maximum speed but fast cruising and occasional wake boarding are typical. The 7.4L was adequate but why not add HP when the checkbook is on the table? http://www.offshoreonly.com/forums/s...96-mag-ho.html |
i have a basically drop in stock 7.4 mpi 225 hours out of a 1998 Ed 419-721-1778
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Originally Posted by Griff
(Post 3258071)
Not sure I'd let your mechanic do anything. He put 15 gallons of antifreeze into the engine before he noticed a problem.
Engine blocks don't just crack for no reason. Did it freeze hard before you took it in to be winterized???? or did the engine overheat recently???? I would just buy the fresh 502mpi in the swap shop or a low hour stock takeout engine. |
Originally Posted by 4bus
(Post 3258244)
What? I would suggest running from this guy.
What engine do you have? 3 gallons of water and you did not notcie it running funny? 15 gallons of antifreeze? Your system holds 5 gallons tops! How was he testing for freeze in a closed system? I agree with the last poster, make sure it is good for winter....I would pull the block plugs and exhaust plugs or have it winterized some where else. Check it out int he spring. Water in oil does not always mean bad block. Could be oil cooler, head gasket, cracked head, intake manifold, exhaust leak. Either you are having trouble relaying what was said from the mechanic to you or the mechanic full of BS. |
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