88 merc 100

[joeb]

i have a mercury 100 i took to the dealer to see if i could change props to get more mph. After 2 lake runs and 2 mouth later he's calls me saying i have a engine knocking at full throtle, but can't hear it in the tank. is this motor worth putting a rebuilt powerhead on?. 2300.00 or is there a cheaper alternative.

 

[joeb]

Re: 88 merc 100

bump

 

[12Footer]

Re: 88 merc 100

I'm leary of this. If you can't hear it, what is this wrench hearing? 2 months to see if you can run more prop? Outrageous.<br />I would run,get my motor from him,and find another wrench for a second opinion...Have them run a compression test.Besides, how do we know if it isn't just stale fuel (2months old)??<br />And it could literally be 5 other causes besides internal. <br />1,loose bolt or plate somewhere.<br />2.lower unit gear play, or notched trust bearing.<br /><br />3,wasp nest under the flywheel<br />4,insulator blanket falling out(hitting the engine).<br />5.one cylinder not firing<br />Or other simple problems. Before tearing-into a job like that,he should be able to pinpoint what the noise is, no ifs, N's, or butts.<br />I hope it's not a rod or wrist pin.

 

[Trent]

Re: 88 merc 100

I concurr with Mr.12footer

 

[joeb]

Re: 88 merc 100

thanks guys for the post.. the dealer (Sea ray) has rebuilt the carbs twice . two lake runs 1754.00 . then hits me with this news about the powerhead. someone told me that if i ran a stainless prop on that motor it could make a knocking sound . hear any thing like that before.

 

[joeb]

Re: 88 merc 100

12 footer now that you mentioned it i had the lower unit rebuit before i took to sea ray. (rec. usa) but that another story. point is ,greenville south carolina is in need for a good boat mech. nobody rebuilds motors. they just want to sell new ones. or spend plenty repairing them.