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wiltok
08-25-2007, 06:42 PM
It's a 310 Predator - runs fine at idle - but when put under a realtively heavy load can hear a fairly loud knocking. Can't locate the exact source of the knock. It has been REALLY wet here - and although the boat was under the shore station canopy it was not covered and did get wet (water did not fill up the engine compartment - it was just really damp). Any ideas before I pull it out and take it to the dealer? I did open the engine cover the leave it in the sun all day to dry out.

Hoosier Bob
08-25-2007, 07:18 PM
You know never to ask these questions on Saturday! Heck only 6 members and most have been drinking! I know of no knock that is a result of moisture. How many hours? Is this a spark knock or does it sount like it could be a lifter or valve? Most crank or rod bearing knocks actually lessen under load in my experience(unless way gone!) ICBW but the moisture could have effected your ignition or spark/advance monitoring causing a spark knock or ping. Moisture IMO would have the most effect here. Yes dry it out. Does the Predator have dedicated coils or a distributor? If it has a dist pull the cap and allow to dry as well. Long story short define knock and some sober people should be along shortly!;)

I would guess "Spark Knock" and yes it gets worse under load. Ignition.

Farmer Ted
08-25-2007, 08:18 PM
did you check the knock sensor?

does your engine have one?

mine is on the right side of the engine with a single wire connector on it.

pull it in the winter to drain the block.....

might have a loose/fouled connection if it's wet......

JimN
08-25-2007, 09:10 PM
If the wires had moisture on them or if they have been on the motor for more than two or three years with heavy use, it may be a cross-fire issue. If the cap was wet, it could do the same thing. Dry it out and try it again. Don't change or add gas, just run it. You want as few variables as possible and adding gas could change things. If water is the only real thing that changes and the problem goes away, you'll know what caused it. If water on the wires and in the cap caused it, it's time to replace them.

cbryan70
08-25-2007, 10:10 PM
most definatly take the cap off and let it dry

wiltok
08-28-2007, 01:38 PM
Thanks for all the responses. The verdict from the dealer - blown head gasket - need new engine (no compression on 3 and 5). It's $5,000 installed (with 1 year warranty) - engine from Indmar. Not a good day - especially since I want to sell the boat. Life goes on....

TMCNo1
08-28-2007, 01:46 PM
Thanks for all the responses. The verdict from the dealer - blown head gasket - need new engine (no compression on 3 and 5). It's $5,000 installed (with 1 year warranty) - engine from Indmar. Not a good day - especially since I want to sell the boat. Life goes on....



I smell a fox in the henhouse, I could be wrong.
The loss of compression on 3 and 5 is probably due to the blown head gaskets and replacing the head gaskets may restore the compression, I'm just sayin'. Please get a second opinion, even if it is from a non-marine mechanic or dealer.

JimN, am I out of bounds here?

Andyg
08-28-2007, 01:46 PM
Wiltok,
That really sucks! How many hours did you have on that engine? Any idea what caused it to blow a head gasket?

Later

Andy

Maristar210
08-28-2007, 01:55 PM
Sorry to hear it, how many hours?

H20skeefreek
08-28-2007, 02:04 PM
uhh....yeah, a blown headgasket does not require a new engine unless the block also cracked. Oh wait, maybe it does. Get the new engine, then let me know where to pick up the "junk" engine. I'll take care of it!

wiltok
08-28-2007, 02:17 PM
Just approaching 600 hours. From what I understand, the boat ran for a while (it was making the noise but not for that long) and it created a 'groove in the exhaust gas port in the engine' which allowed fuel to be dumped into the engine oil. They checked the oil when I brought it in and it was several quarts high. I have a reputable dealer - I honestly don't think they just trying to sell me a engine (I might be getting the technical description not exactly right - I was in shock when I was talking to them).

Anyone looking for a 2001 X-9 excellent exterior/interior condition with a new block? I was going to sell it anyway, we ski more than we board so we are buying a 197. Comes with a one-year transferable warranty.

wiltok
08-28-2007, 02:18 PM
Andy,

No idea what caused it to blow. I meant to tell you - the IPod hookup works great!!!!

TMCNo1
08-28-2007, 03:06 PM
Just approaching 600 hours. From what I understand, the boat ran for a while (it was making the noise but not for that long) and it created a 'groove in the exhaust gas port in the engine' which allowed fuel to be dumped into the engine oil. They checked the oil when I brought it in and it was several quarts high. I have a reputable dealer - I honestly don't think they just trying to sell me a engine (I might be getting the technical description not exactly right - I was in shock when I was talking to them).

Anyone looking for a 2001 X-9 excellent exterior/interior condition with a new block? I was going to sell it anyway, we ski more than we board so we are buying a 197. Comes with a one-year transferable warranty.

Before spending $5000 on a new engine, I believe I would get the damage description written down by your reputable dealer on paper and consult someone on here like Jim N or EngineNut (Indmar employee) for a easier fix. Something still just does not sound right and for that kind of money and your selling the boat, you deserve better, IMO.

BrianM
08-28-2007, 03:40 PM
I agree that it doesn't sound like a need for a complete new engine. At most a rebuild which I would imagine should only cost about half of the cost of a new complete engine.

wiltok
08-28-2007, 03:57 PM
I will try to get a better description of the problem - my brother is asking as well (he pretty well versed in enginespeak). The problem is that we still have about 6 weeks of skiing and we are anxious to get back on the water. I don't want to get screwed obviously - but I feel that selling the boat with a new Indmar block would be easier and might (I stress might) get more money (including the warranty). I'm not made of money but if I can pick up another 1000 or so on resale it would probably be worth it going new.

BrianM
08-28-2007, 04:22 PM
If you can do a rebuild for $2500 or a new block for $5000 even of you get $1000 more at resale time you still lose

beatle78
08-28-2007, 05:35 PM
I vote for 2nd opinion or at most try to rebuild the block..... whoever rebuilds it usually puts some sort of warranty on it.... probably not 1 year, but people here rebuilt and they think "wow this engine is brand new"

wiltok
08-28-2007, 06:12 PM
OK - the failed head gasket allowed a groove to form between two cylinders from the gases transfering back and forth (which is why there is no compression on 2 cylinders). This groove is in the actual block - and is thus not repairable. Does that make sense to you guys?

H20skeefreek
08-28-2007, 07:08 PM
I don't know how gases travelling back and forth would cause a groove in the cylinder wall, but I'm not an engine expert, but even if it did, it wouldn't be enough damage that boring or honing the cylinders couldn't fix.

TMCNo1
08-28-2007, 08:13 PM
I don't know how gases travelling back and forth would cause a groove in the cylinder wall, but I'm not an engine expert, but even if it did, it wouldn't be enough damage that boring or honing the cylinders couldn't fix.
Or even sleeving those 2 cylinders or just a replacement block, but I still don't buy it, cause it would take a long time of leaking for the gasses (????) to wear away that much metal and you didn't run it forever ticking did you?

boxman3
08-28-2007, 09:00 PM
I would look in to rebuilding the motor with bore and sleeve repairs to the cylinders in question. Or bore the motor out to .030 with oversized pistons. MORE HP!!!!!

You could have dropped a ring and caused this level of damage. The money is always the question. Did anybody say anything about a repalcement Jasper Engine??

TMCNo1
08-28-2007, 09:20 PM
I would look in to rebuilding the motor with bore and sleeve repairs to the cylinders in question. Or bore the motor out to .030 with oversized pistons. MORE HP!!!!!

You could have dropped a ring and caused this level of damage. The money is always the question. Did anybody say anything about a repalcement Jasper Engine??
Check out this thread and advance search under the word, "jasper", cause there are other threads concerning replacement marine engines by other manufacturers there too, http://www.tmcowners.com/teamtalk/showthread.php?t=18409&highlight=jasper

JimN
08-29-2007, 03:16 PM
Wiltok- If the gasket was bad and it's a FORD, 3 and 5 aren't on the same bank- 1-4 on the passenger side and 5-8 on the driver's side. Between 3 and 4, I would believe. The lack of gasket material will cause loss of vacuum, too. This means that little gas should have gotten in, and while some would, how long the motor ran that way will determine how much damage was done. Take some photos and post them, if you can. I can't see how the gases could have removed that much material since the combustion wouldn't be complete and therefore, not as hot as normal. OTOH, the deck can be shaved a bit and if a cylinder is cracked, it can be bored and sleeved. Another way to go it the re-manufactured motor. Jasper comes with at least 18 month warranty, unlimited hours. Personally, I would call around- $5K is high.

wiltok
08-29-2007, 03:33 PM
Thanks everyone. My wife is actually working out of an office near the dealer today and she is going to stop by to check it out (hopefully with a camera). I'll report back when I know more...