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CRACKED BLOCK

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"I HAVE A 1981 COBALT RUNABOUT

"I HAVE A 1981 COBALT RUNABOUT W/ A MERCRUISER 260 ENGINE.
THE ENGINE HAS NEW HEADS/ GASKETS & MANIFOLDS.
BOAT RAN FINE THE LAST TIME I HAD IT IN THE WATER. THIS WEEK, I PUT THE BOAT INTO TAHOE & IT IMMEDIATELY WOULDNT RUN. I FOUND MAJOR AMOUNTS OF WATER IN OIL/ CARB/VALVE COVERS ETC.
MY MECHANIC SAYS HE SUSPECTS THERE IS A CRACK IN THE BLOCK SINCE IT IS THE ONLY ITEM ON THE ENGINE THAT IS ORIGINAL ( 500-600 HRS ) HE SAYS HE NEEDS APPROX $4K TO HAVE THE BLOCK REBUILT.
I SEE REMANUFACTURED SHORT BLOCKS ONLINE FOR $ 1200.00 & I'M THINKING $4K SOUNDS HIGH.

MY QUESTIONS ARE:
1. IS THERE ANY OTHER WAY I COULD BE GETTING HUGE AMOUNTS OF WATER IN THE ENGINE FROM SOMETHING OTHER THAN A CRACKED BLOCK?? I MEAN SOMETHING MAJOR MUST HAVE BROKE. WHAT DIAGNOSTIC TESTS CAN BE RUN TO CHECK TO SEE IF ANY OF THE TOP END STUFF COULD BE THE SOURCE OF THE LEAK, WITHOUT HAVING TO TAKE THE ENGINE OUT OF THE BOAT.

2. ARE THERE ANY MECHANICS IN THE SAN FRAN BAY AREA WHO CAN SWAP OUT AN ENGINE BLOCK FOR A REASONABLE PRICE?? WHERE IS THE BEST SOURCE TO GET A SHORT BLOCK??

I LIVE IN REDWOOD CITY, CA.

THANK YOU,
BRIAN"
 
"Brian,
You can find complete

"Brian,
You can find complete rebuilds from $1000. up to $3000. and new from $2800.
All depends on where you are looking.
If your mechanic wants $4000. for a short block he must be thinking of taking a vacation. I wouldn't even go back there.
A few questions. Why did you have the heads done, did this same mechanic do the work, did the engine get hot the last time you used the boat?
There are ways for checking some areas of the block without removing the engine. It depends on what is damaged / cracked."
 
"Maybe his cat needs a hairbal

"Maybe his cat needs a hairball surgically removed.

Brian- Maybe that's the going price where you live, though. It's not Cope & Mc Phetres, is it?"
 
"previously, we overheated the

"previously, we overheated the engine pretty good which resulted in blown head gaskets. mechanic ( "all marine" in stockton, ca. ) replaced the gaskets & installed 1 new head which had a small crack. the other head was ok.
we ran the boat 4-5 times & all was good. temp low, engine ran like a top. mechanic warned me that lower part of engine had 500+ hrs. on it & that bearings were worn, causing low oil pressure ( 25 psi ) i told him i just wanted the boat to run cool & i would replace the bearings /low end once she blew a couple of seasons down the road.

so like i say, the boat ran like a top the last time i took her out.

so now last monday, i am all geared up to go to lake tahoe boat-in campsite. we put the boat in the water & shove off. immediately i can tell that something is wrong. engine would rev up ok in neutral but when i tried to accelerate it in drive it would just bog down & not run. i was able to crawl over to the nearest marina where the mechanic came down & noticed water in carb/ valve covers / oil pan etc. engine temp was cool all the way to marina though.
i am thinking that something the mechanic did to heads didnt take & that is where water is leaking from. he said he will do comp. test & "other" tests to check it out but he thinks block is cracked. i dont see how all of a sudden block could crack, but since crank/ bearings are old, i wouldnt mind replacing anyway but want a good price.
all i really want to do is stop water from entering engine, not rebuild engine.
what do you think???

thank you,
brian"
 
Well the other head could have

Well the other head could have cracked but as far as the block is concerned the worn bearings would have nothing to do with water entering the engine. If it threw a rod then yes it could break the block.
This is just a guess of course but the heads may not have been torqued right or OR the guy used an automotive type head gasket instead of the stainless steel marine gasket.

If all else fails put a ton of stop leak in the lake.
Just kidding. Hope you have a little humor left.
 
$4k for a reman engine install

$4k for a reman engine installed is not a bit high but not huge ly over priced if done at a marina. I do them for $3k with a 2 year warranty from a national chain ( you can get it covered at any repair facility). Try to get your $1000 engine covered. Some tings folks don't understand is the labor required to change the long block. Usually 10 to 15 hours to clean and inspect every part and re-assemble.

Jo JO the shadetree with his $50 box of rusty tools can save you a lot of money. If you had a heart attack would you got to a vet or a heart doc?

The small block chevy in marine use has a problem with the intake rusting thru under the t-stat hsg and at the head mating service check these before dumping a lot money.

Mercruiser manuals state idle oil pressure should be no less 5-10 psi. A common rule of thumb is 10 psi for every 1000 rpm upto 40 psi.

Please tell me where I can get a NEW 260 horse for $2800.
 
"MARINE BASE ENGINE 350 (S

"MARINE BASE ENGINE 350 (Split Rear Seal) 12" FW

Replaces 350 c.i.d. chevy marine engines produced before '85
All new but all old parts fit, like flywheel, coupler, bell
housing, and exaust. In short you just move the external
parts and check timing. No retro-fit problems, anyone can
do it. If your engine isn't split seal, use other engine.
Order Part Number: IMOT350S
Your discounted price: $2,295.00 plus S&H"
 
"$2300 for a rebuilt engine w/

"$2300 for a rebuilt engine w/ warranty is a good price. Most reputable places will start at 3K for a reman 260. The labor to install will probably be another $1000 and a couple hundred for liquids, seals, gaskets and such and your at $3500 easy.

A NEW motor (not rebuilt), is probably going to run well over $3K, more like $5K-6K plus installation.

Yeah you can find long block 5.0 marine remans for $1300, but if something happens kiss the labor to pull out and reinstall goodbye. If you get lucky and it works great, but I have been bitten by those cheaper guys, now I go with Jasper. No question on warranty issues and any Jasper dealer will do the work, because Jasper pays them if there is a problem.

I guess its all about if you are a gambler or not. You better believe Jasper could sell there carb to oil pan motors for $2K, but your paying the extra money for piece of mind on warranty issues."
 
Unless I'm missing somethi

Unless I'm missing something in Charlie's post it does say all new. Doesn't that mean a new not rebuilt engine?
Where is the engine from? More information needed.
 
"Well buddy, water in the oil

"Well buddy, water in the oil is unfortunately not a real good thing, however, all may not be lost. First, I would check the other head that supposedly was good. It that isn't the problem, you may have cracked the block when you had her out and didn't realize it. Do uyou have an aluminum block or cast iron? If you get an aluminum block hot, they will crack faster than cast iron. I would change out all the oil and filter and replace the oil with new. Crank it and if it runs, watch the temp gage. Then check the oil again. If water is in the oil, you probably have a cracked block. I hate to say it but how well do you know the reputation of the mechanic? You know these guys can be unscrupulous some times and repeat business is what pays their bills. I know for a fact that sabotage occurs in the automotive mechanic business, so be careful. I was a victim. Good luck."
 
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