Piston Slap noise in marine 8.1L

[6MISFITZ]

There has been allot of discussion about GM cold start piston slap in the 8.1L truck engines.<br />I have not been able to find this complaint about the 8.1L marine engine which comes in at 375 HP and 425 HO HP ratings.<br /><br />Is the noise of the marine exhuast masking this problem?<br />Do the mairne pistons have a longer skirt design VS the truck piston?<br />For the higher HP marine engines, are the pistons are forged vs cast.<br /><br />The marine 8.1L seems to be the engine of choice to repower with lots of customer recommendations and rave reviews from magazines articles.<br />Any comments or concerns?<br /><br />Thanks <br />Mike.

 

[a.d.mobile]

Re: Piston Slap noise in marine 8.1L

this is a big one with the trucks and your marine engine is the same execpt exaust manifolds the rest is the same crank,rods,pistons,cam. the good thing yes they make noise as anything does with a short skirt. the short skirt makes H/P and noise in return that motor will last forever. it only makes the noise on cold start when the temp comes up the piston expands and she will quiet down. the only way a forged piston got in there is if someone other than g/m put them in. just keep good oil in engine and have fun!

 

[chris in va]

Re: Piston Slap noise in marine 8.1L

Not that it's a boat, but my 94 Jeep Cherokee makes some serious piston slap when cold. Guess what, these engines tend to last over 250k miles. Thicker oil quiets it down a bit, but I wouldn't worry too much about it.

 

[6MISFITZ]

Re: Piston Slap noise in marine 8.1L

Thanks for the replys gentlemen.<br />Mike.