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Cracked engine block


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Well, I've done it. I managed to screw up my winterization and now I have a cracked block.

I have a 1990 Sunsetter with a 5.7 Mercruiser. The block is cracked and my motor will have to be rebuilt with a new block. I don't think the heads or exhaust manifolds were damaged, but I'm going to double check.

My question is: I've found a 350 vortec block for $150. I know my exhisting heads, intake manifold, and carb can be bolted on to that block. I know I'll have to find a new timing chain cover. My question is will I have to replace the fuel pump from the current mechanical pump to an electric one. If so, do I have to replace the whole pump assembly in the tank? If so, how much do they typically cost?

I'm hoping there's a way to use the existing fuel pump.

Any thoughts?

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Well, I've done it. I managed to screw up my winterization and now I have a cracked block.

I have a 1990 Sunsetter with a 5.7 Mercruiser. The block is cracked and my motor will have to be rebuilt with a new block. I don't think the heads or exhaust manifolds were damaged, but I'm going to double check.

My question is: I've found a 350 vortec block for $150. I know my exhisting heads, intake manifold, and carb can be bolted on to that block. I know I'll have to find a new timing chain cover. My question is will I have to replace the fuel pump from the current mechanical pump to an electric one. If so, do I have to replace the whole pump assembly in the tank? If so, how much do they typically cost?

I'm hoping there's a way to use the existing fuel pump.

Any thoughts?

Sorry to hear the bad news, I can't answer your fuel pump questions.

Can you tell us more about how you winterized and what you think went wrong? What area of the block cracked? Any pictures?

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Sorry to hear the bad news, I can't answer your fuel pump questions.

Can you tell us more about how you winterized and what you think went wrong? What area of the block cracked? Any pictures?

Long story and very, very stupid on my part.

I don't typically have to a complete winterization because of our warm climate. Normally, I connect my connect my boat up to my hose, crank it up, and pour anifreeze in the motor unitl it runs out of the exhaust. That particular day I started the process, but got interrupted by an emergency and wasn't able to get back to it for a couple of weeks. I couldn't remember how far into the process but apparently I didn't get as far as I originally thought. The winter was a LOT colder that what we are used to and now I've got a boat without a working motor.

I'll post some pictures, but the crack starts above the freeze plug, moves diagonally up and horse-shoes back around. About a six inch crack in total.

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Bummer. I'm wondering if there would have been any difference had you gone the "drain everything" route rather than using anti-freeze. :unsure:

Wish you well on the new engine install.

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Bummer. I'm wondering if there would have been any difference had you gone the "drain everything" route rather than using anti-freeze. :unsure:

Wish you well on the new engine install.

I think there would have been a difference. Like I said; it wasy my screw up. That will never happen again.

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I think I know what you are asking, and I think there is still a place on the vortec block to mount a mechanical fuel pump and it's just covered with a block-off plate. But I'm not 100% on that and my boat is still in storage. It's been a while since I've paid attention to that and maybe the casting is there but it's not punched out. Someone here can take a quick peak.

A head that's cracked by freeze will usually be pretty obvious by visual inspection like the block. But I have seen exhaust manifolds that look fine to the eye but don't pass the pressure test. You can make a simple block off plate and bolt it to the manifold where the riser would normally attach; then put a schrader valve in one of the threaded ports and a pressure guage in the other one. Put 20-30 psi of air in it and spray it with soapy water.

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There are many variations of the Vortec engine, if the one you have located is an L31 which is the 5700cc (350 cid) cast iron version it will have the mechanical fuel pump boss. Make sure you are getting what you think you are purchasing as there are many variations of the Vortec engine configuration. The term Vortec really described the cylinder head flow. You will also need to check the intake manifold bolt pattern as that changed from perpendicular to the head face to a vertical to earth configuration. Sorry to hear about your dilema.

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Call your insurance company. That should classify as an accident. Pay the deductable and get a new engine installed at the dealer or a shop of your choice.

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Call your insurance company. That should classify as an accident. Pay the deductable and get a new engine installed at the dealer or a shop of your choice.

Freeze damage is almost never covered by insurance.

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Bummer man, sorry to hear this. I also live in the Jackson area, (Brandon). It was very cold here this winter. I plan on pulling mine out this weekend and giving it a good look over. It's getting time to get on the water. I hope all goes well with your replacement.

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Sorry for your problems. There should be a engine block ID number, you need to make sure your new block matches GM makes changes from year to year they match so that everything will bolt on. if you have a number of what you have and what you are looking at I can check and see if they match.

CB

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Bummer man, sorry to hear this. I also live in the Jackson area, (Brandon). It was very cold here this winter. I plan on pulling mine out this weekend and giving it a good look over. It's getting time to get on the water. I hope all goes well with your replacement.

It is getting to be that time. You live near the Rez (39047) or the Brandon proper (39042). I grew up in Brandon proper.

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Sorry for your problems. There should be a engine block ID number, you need to make sure your new block matches GM makes changes from year to year they match so that everything will bolt on. if you have a number of what you have and what you are looking at I can check and see if they match.

CB

I just sent an email to the guy I'm thinking of buying it from. I'll let you know what he tells me

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It is getting to be that time. You live near the Rez (39047) or the Brandon proper (39042). I grew up in Brandon proper.

HaHa I guess you would say proper is where I live, right off HWY 471.

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I'm going to back up what everyone else here said, and offer a few more insights. I put a rebuilt Vortec longblock on my 96 Sunsetter due to a freeze crack.

-I doubt that a Vortec block will accept your intake manifold if the engine is original from 1990. The Vortec wasn't available then, and it has a different bolt pattern and angulation than non-Vortec blocks. The Vortec has 8 bolts that drop into the intake manifold from directly above. The earlier, non-Vortec blocks have 12 bolts (I think??) and they go in at an angle. Check the casting number of your block as mentioned before, and there are plenty of internet resources that will interpret it for you.

-My Vortec block has the housing for a mechanical fuel pump, but no holes drilled where they needed to go to get the pushrods hooked up. This was not a problem for me, since mine is an electric fuel pump, but it will be a problem if you plan on installing a manual fuel pump. So, my casting was ready to accept it, but it wasn't machined for one. Check this carefully as there may be variations on Vortec blocks.

-I'd also recommend putting a longblock in rather than a short block, based on my conversations with 3 shops that rebuild marine engines. 100% of my limited sample size recommended the long block over the short block due to the problem of warped heads that look visually just fine.

-Does the block you're looking at have the correct bearings and freeze plugs? Is it a marine block? There's no magic to marine 350s, but it should have the right parts on it to do the job.

-If you decide to get a rebuilt marine block, I'd recommend Rapid-O marine in Florida. They have reasonable prices and only rebuild engines to marine specs. They were able to match my casting number exactly. Certainly more than $150, but you get a rebuilt engine that should last you a lot of years with minimal headache.

Good luck, the engine swap on mine was actually pretty fun!

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