boat motor gone bad!!!
06-16-2010, 10:27 PM
#21
Registered
Join Date: Jul 2009
Location: Grosse Pointe Farms, MI
Posts: 1,570
Likes: 0
Received 2 Likes
on
2 Posts
You could be getting water into your block through a leaky exhaust manifold, which is why I suggested doing everything you can to make sure it is a cracked block before you go and buy a new one and swap everything over.
06-16-2010, 10:34 PM
#22
Registered
Thread Starter
Join Date: Jun 2010
Location: Kansas City, MO
Posts: 53
Likes: 0
Received 0 Likes
on
0 Posts
Gonna go out on a limb here, and say I have to disagree. He spent $18,500 on the boat...and still owes $16,000. That means he FINANCED it. There is no way he should take a chance on another $12,000 in motors. What happens if he spends the money on these "low hour motors", then something mysteriously happens to one or both of those ? I say pull the motors yourself. DO ONE MOTOR AT A TIME. Have a friend or two help you. Get good advice from numerous people (dont just tear something off cause uncle bill told you to). Ask 5,6,8 people about what you run into, then take a general consensus. Get info from the internet on what your working on that day. Work SLOWLY and mark everything. Put parts in zip lock bags and mark where they came from. Mark wires and hoses. Take pics with your phone. Keep a computer diary.Then find a reputable engine shop in your area, and ask questions. They want to help so you'll tell others about them. You should be able to rebuild both motors for less than one of the used ones. In the end, you'll have two new motors that YOU built, you'll know whats in them as far as parts and machine work, and you'll have learned something new. There is no feeling in the world like building a motor yourself, and firing it up for the first time. Remember I said this when you and your wife are cruising and listening to the sound of those big blocks that YOU built. Take your time...and get good solid info. I think you can handle this. I really do. 
Do you feel that the engine shop needs to specialize in marine engines? or would any "reputable" engine shop be capable of assisting me in a rebuild. I would love to build my engines myself and if I get one done and be back on the water for the late season I would definitely have the modding bug by the time its too cold outside to be on the water.... and wind up getting subpoenaed by my wives' attorney while holding a wrench hovering over another new top end kit in the garage all while feeling "this is totally worth it!" haha! But, your right! I do as much of the work on our vehicles as I can convince my wife I'm capable of doing.... and after doing that I always feel that the cramping back is just a reminder that I'm awesome! haha! I love the feeling of accomplishment I get after spending an afternoon turning a wrench!
Thank you so much for your advice!
06-16-2010, 10:39 PM
#23
Registered
Thread Starter
Join Date: Jun 2010
Location: Kansas City, MO
Posts: 53
Likes: 0
Received 0 Likes
on
0 Posts
I would rebuild as well. Since this unfortunatly happened in the summer you have pleanty of time until next summer to rebuild. I rebuilt 2 small blocks in the matter of 3 months only working on the weekends and some nights. It's really not rocket science to rebuild
either. A couple of good books and some local advice from the machine shop helped out big time. In also got the video from boxwrench.net and it helped great for those steps you can't visualize from
a book.
Tinman is right, the satisfaction from building your own motors is great. And if anything goes wrong you know the motors inside and out.
either. A couple of good books and some local advice from the machine shop helped out big time. In also got the video from boxwrench.net and it helped great for those steps you can't visualize from
a book.
Tinman is right, the satisfaction from building your own motors is great. And if anything goes wrong you know the motors inside and out.
Thank you very much for your advice!
06-16-2010, 10:52 PM
#24
Registered
Thread Starter
Join Date: Jun 2010
Location: Kansas City, MO
Posts: 53
Likes: 0
Received 0 Likes
on
0 Posts
At this point I would pick up the motor myself from the marina. You don't seem to have good results with them anyhow, and it doesn't sound like they're all that competent.
I would try to pressurize what you can of the cooling system and see if you can get water to leak into the block from somewhere. I guess you could have a crack somewhere that only opens when the motor gets hot, or when it's under power, but to assume that the block is junk just because water is ending up in the cyls or oil to me seems irresponsible. I would want to make sure I needed a block before I went out and did a ton of work swapping everything out.
If you can't get water to leak into the block with hose pressure or otherwise, I would rig the motor to run on a cradle in the garage with a garden hose supplying water to the motor. I would do everything that I could to make sure that it WAS a cracked block before I did all that work swapping blocks.
I would try to borrow some car headers and mufflers to run the motor in the garage. It will eliminate the possibility that a cracked exh. manifold is giving you problems, and help to isolate the block as the problem, if you end up finding a problem.
Regardless of the outcome of your water investigation plan on sending the heads off to a local machine shop to have them rebuilt. Have the valves ground, new guides put in place, and new seals installed. It shouldn't cost all that much to have this done, and at 500 hours you're ready for some valve work.
Don't count your boating season over yet! There's still a few warm months. There really isn't any reason that you shouldn't be able to get this thing back together reasonably quickly.
I would try to pressurize what you can of the cooling system and see if you can get water to leak into the block from somewhere. I guess you could have a crack somewhere that only opens when the motor gets hot, or when it's under power, but to assume that the block is junk just because water is ending up in the cyls or oil to me seems irresponsible. I would want to make sure I needed a block before I went out and did a ton of work swapping everything out.
If you can't get water to leak into the block with hose pressure or otherwise, I would rig the motor to run on a cradle in the garage with a garden hose supplying water to the motor. I would do everything that I could to make sure that it WAS a cracked block before I did all that work swapping blocks.
I would try to borrow some car headers and mufflers to run the motor in the garage. It will eliminate the possibility that a cracked exh. manifold is giving you problems, and help to isolate the block as the problem, if you end up finding a problem.
Regardless of the outcome of your water investigation plan on sending the heads off to a local machine shop to have them rebuilt. Have the valves ground, new guides put in place, and new seals installed. It shouldn't cost all that much to have this done, and at 500 hours you're ready for some valve work.
Don't count your boating season over yet! There's still a few warm months. There really isn't any reason that you shouldn't be able to get this thing back together reasonably quickly.
Thanks for your advice!
06-16-2010, 11:06 PM
#25
Registered
Thread Starter
Join Date: Jun 2010
Location: Kansas City, MO
Posts: 53
Likes: 0
Received 0 Likes
on
0 Posts
Thanks again!
06-16-2010, 11:14 PM
#26
Registered
Thread Starter
Join Date: Jun 2010
Location: Kansas City, MO
Posts: 53
Likes: 0
Received 0 Likes
on
0 Posts
I'd scrap the whole boat, save up for a year and buy something with lower hours next year. Though I know it would suck to do that, it doesn't make sense investing $12,000 that you don't have into a boat that is only equally worth that amount. You'll be $24,000 deep into a boat that's only worth $12,000-$15,000 (guesstimate).
Thanks again for your advice!
06-16-2010, 11:24 PM
#27
Registered
Thread Starter
Join Date: Jun 2010
Location: Kansas City, MO
Posts: 53
Likes: 0
Received 0 Likes
on
0 Posts
Marine exhaust manifolds have water jackets that allow water to flow through the manifold. At the head the water and exhaust are kept separate, after the riser the water mixes with the exhaust and heads out of the tail pipe together.
You could be getting water into your block through a leaky exhaust manifold, which is why I suggested doing everything you can to make sure it is a cracked block before you go and buy a new one and swap everything over.
You could be getting water into your block through a leaky exhaust manifold, which is why I suggested doing everything you can to make sure it is a cracked block before you go and buy a new one and swap everything over.
thanks for the explanation on dry pipes... I am definitely going to take the motor somewhere else for a second opinion.. although with the previously described pogo stick sounding start ups, I think there is definitely something wrong... or maybe not quite right... somewhere.... I have an auto mechanic that I trust with anything auto related (if I were a car I would trust him with my life) as do 40 or so other people I work with.... do you think that it would be ill advised to ask him to take a look at the motor and see what he thinks? or are marine engines similar enough to automotive engines that he should be able to tell me the thick n thin of it?Thanks again for the advice!
06-17-2010, 12:53 AM
#28
Charter Member # 55
Charter Member
I really do not know of any good shops in the KC area. To my knowledge there really are none. Your best bet would be to haul the boat to LOTO. I would call Brett at Performance Boat Brokerage. The problem is your limited budget. They will give you straight answers on what is wrong and you can go from there.
If you were only turning 4250 rpms, then boat was propped wrong to start with. 454 mags should be propped to turn 5000rpms. The props were 2-4" in pitch to big.
There are a lot more ways for water to get into an engine than because of a cracked block. I agree with what was said about your current mechanic winterizing it. If the block is cracked after they winterized it in the Spring, then it is their fault. Also, the water mixed with the oil sitting in the engine is no doubt causing more damage. Exactly how did they determine that the block was cracked???? Unless they can see the crack, then its a guess.
Water can get in through bad exhaust riser gaskets, bad inatke gaskets or bad head gaskets, or cracked exhaust manifolds.
The biggest thing is the original stalling of the engine. Why???? 185* is not that high. It sounds like the original issue was caused by you backing off the throttles too fast and the engine ingested water through the tail pipes. Then the mechanic did not diagnose or correct the problem. This lead to more issues and wasted money.
I would cut your losses now and go pick up your boat and engine. You have plenty of time to figure out a solution. It really does not sound like they know WTF they are doing.
You can always start taking the engine apart yourself, but if you don't know what you are looking for, you probably won't find the problem.
If you were only turning 4250 rpms, then boat was propped wrong to start with. 454 mags should be propped to turn 5000rpms. The props were 2-4" in pitch to big.
There are a lot more ways for water to get into an engine than because of a cracked block. I agree with what was said about your current mechanic winterizing it. If the block is cracked after they winterized it in the Spring, then it is their fault. Also, the water mixed with the oil sitting in the engine is no doubt causing more damage. Exactly how did they determine that the block was cracked???? Unless they can see the crack, then its a guess.
Water can get in through bad exhaust riser gaskets, bad inatke gaskets or bad head gaskets, or cracked exhaust manifolds.
The biggest thing is the original stalling of the engine. Why???? 185* is not that high. It sounds like the original issue was caused by you backing off the throttles too fast and the engine ingested water through the tail pipes. Then the mechanic did not diagnose or correct the problem. This lead to more issues and wasted money.
I would cut your losses now and go pick up your boat and engine. You have plenty of time to figure out a solution. It really does not sound like they know WTF they are doing.
You can always start taking the engine apart yourself, but if you don't know what you are looking for, you probably won't find the problem.
06-17-2010, 06:14 AM
#29
Charter Member #232
Charter Member
You sure it is not just the exhaust manifolds cracked or leaking? Sounds to me like your mechanic may not be tops.....
__________________
Put your best foot forward!
Put your best foot forward!
06-17-2010, 08:39 AM
#30
Registered
Join Date: Jul 2009
Location: Grosse Pointe Farms, MI
Posts: 1,570
Likes: 0
Received 2 Likes
on
2 Posts
Oh, Ok thanks for the explanation on dry pipes... I am definitely going to take the motor somewhere else for a second opinion.. although with the previously described pogo stick sounding start ups, I think there is definitely something wrong... or maybe not quite right... somewhere.... I have an auto mechanic that I trust with anything auto related (if I were a car I would trust him with my life) as do 40 or so other people I work with.... do you think that it would be ill advised to ask him to take a look at the motor and see what he thinks? or are marine engines similar enough to automotive engines that he should be able to tell me the thick n thin of it?
Thanks again for the advice!
thanks for the explanation on dry pipes... I am definitely going to take the motor somewhere else for a second opinion.. although with the previously described pogo stick sounding start ups, I think there is definitely something wrong... or maybe not quite right... somewhere.... I have an auto mechanic that I trust with anything auto related (if I were a car I would trust him with my life) as do 40 or so other people I work with.... do you think that it would be ill advised to ask him to take a look at the motor and see what he thinks? or are marine engines similar enough to automotive engines that he should be able to tell me the thick n thin of it?Thanks again for the advice!
Your auto mechanic should be able to look at your motor for you. It's kind of hard because the issue you're having is most likely a marine issue (it has everything to do with a marine cooling system, rather than an auto cooling system).
I wouldn't worry too much about the "pogo stick" sound. You're going to get funny noises when you have water in your cylinders. Something may well be broken, but cross that bridge when you find out what.
If you drain the oil, borrow a set of auto exh. manifolds, and get it to run in your garage you should be able to tell (a) if your block is cracked, and (b) if there's anything wrong with your block as it stands. At that point your motor will basically be an automotive motor, except for the brass freeze plugs and cam.
I agree with Griff that your issue was likely caused by water entering in through the exhaust, possibly from stopping too fast. Does your exh. have the rubber flaps on the tips (or should it?) and if so, are they in decent shape?
IMO an exh. issue is much more likely than a cracked block, given the series of events (it worked for a while this spring).
