overheating at idle

[dhdremodel]

i have an 03 24v with a pcm 330 temp alarm went of a couple of weeks ago at the lake so we brought it to the dealer they said it needs new impeller and circulation pump so we did that took it to the lake the next weekend and alarm went of 10 minutes after we got it of the trailer so took it back to the dealer now they say we need a t stat and a temp sending unit and the trans cooler needs cleaning so we pay them for that (about a grand so far)we get it back and take it to the lake and does the same thing exept now my temp gauge does not work so i am feeling the tops of the manifolds and if you bring it up to about 1300-1500 rpm they cool right of so we cruies around the lake at about 20 mph and manifolds are ice cold but when you stop they heat right up i need to fix the temp gauge first to confurm the temp fluxuation but i am at a loss and am begining to think my dealer canot fix this i have read some were of a problem like this that the shaft seal on the raw water pump was sucking air could that be it we have been though everything els any help would be great Thanks

[bobbysky]

No idea on your problem, but you might want to punctuate your sentences because it's hard to read.

[dhdremodel]

yea sorry just started typing.dont know how to edit

[chpthril]

1st - are you sure it's engine temp setting off the alarm? What was the engine temp normally running before the alarm started to sound a few weeks ago and what is it running now (before the dealer broke the gauge)?

Based on what you are experiencing - hot at idle, cool at cruising speed, i'd say that it's a water flow problem somewhere between the scoop and the engine. At idle, there's not enough water flow to keep the engine within normal range, but with the boat under way, the forced water volume is there and the engine temp normalizes. I would first look at the condition of the impeller housing, then check the trans cooler, v-drive cooler, the scoop and all the hoses from the scoop to the engine.

[dhdremodel]

no blockage. dealer went though everything. i think they are stumped. and i dont want to take it back to them becouse they are chargeing me 109 an hour to do trial and error and nothing is working and have been though the hole system. exept for replacing the whole raw water pump.
boat has 120 hrs would the water pump be worn out all ready?

[chpthril]

no blockage. dealer went though everything. i think they are stumped. and i dont want to take it back to them becouse they are chargeing me 109 an hour to do trial and error and nothing is working and have been though the hole system. exept for replacing the whole raw water pump.
boat has 120 hrs would the water pump be worn out all ready?

My fear is that your dealer has missed something, sounds like they are tossing darts at it instead of actually diagnosing the symptoms. Although 120 hrs is low, one smoked impeller could score the housing and heat it to the point of being out of round.

[dhdremodel]

yes that is why i am nervous about taking it back to them becouse they are just replacing stuff and charging me for it without knowing if that is the couse of the problem and then giving me it back and saying its fixed. can they mic it out to see if it is out of round?

[dhdremodel]

problem solved. dealer took apart the exhuast manifolds and they had blockage. cleaned them out and is running fine now thanks for your imput

[chpthril]

Good news, what did the blockage comprise of?

[dhdremodel]

looked like impeller and sand will be installing a filter on pickup line next week any ideas on what one i should use had an imppeller come apart but i thought i found all the peices does not take much to couse a problem