5.7 wont idle - Maxum Boat Owners Club

Watered down · 10-05-2009, 04:21 PM

I could use a little advice here, I have a 97 2100 SR2 with the 5.7 2brl carb. I wasnt aware of the effects of E10 last year before I winterized. I always use Sta-bil, but it was not the improved ethanol formula. This year, after de-winterization, it ran and fine idled smooth. First time out to the lake it ran great at first, but then wouldnt idle, only stall. I did some fiddling around and discovered I had a bad intake manifold gasket, so I replaced those, thinking that might be why. Well, it still wont idle, just stalls. With the throttle in the first position just past neutral, it will idle but is very rough, it does rev freely, however. At about 1800 rpms, I can feel a cylinder kick in and out, so I am not quite sure If I have a carb problem, a ignition problem or maybe some bad gas. I hope its not the gas, my tank is full and thats a lot of gas to siphon. I plan on a tune up, sure it needs new plugs and wires, but I still dont think that is the problem with the idle. Like I said, it will run at higher rpms and will hit WOT with no problem. Keeping my fingers crossed it is something small and inexpensive. On a side note, I couldn't believe how clean it was under the intake, the block almost looked new. I have plenty of experience tearing down auto engines and they are not usually that clean.

seapuppy · 10-05-2009, 08:17 PM

welcome to the zoo....I'm not sure that what your experiencing is solely just a gas problem...I'd replace these items and go from there....distr. cap/rotor..plugs...wires...points if you have them and ensure that they are dwelled properly....check total advanced timing....

and as for clean inside the block..boat engines don't have the heat build up that usually comes with a car engine ..that's what usually causes the oil to coke up and stick to everything...I once tore down a corvette engine a guy swore by quaker state....the heads had the oil all coked up where the rocker rods came thru...everything had this ugly layer of coke except where the rods came up thru the head....only cuz they had enough spillage to keep it from sticking....when i got done rebuilding the engine..you could eat of the engine...then I scolded him for using quaker state oil....I think that stuff still has parts of the dyno that didn't decay!!...

SP :hello:

rs1lollie · 11-08-2009, 01:53 PM

It could be a clogged fuel filter, (rough idle= less fuel suction, WOT= more fuel suction)

Watered down · 11-09-2009, 01:55 PM

I really haven't had time to do anything about it yet, I have changed the filter/seperator. The more I research it, the more I think I might have a carb problem due to bad fuel. I have seen several posts on the internet with similar issues and thats what their problem was. Luckily I have all winter to deal with it now. what a lousy year, I only made it on the water once and then this came up! I plan on draining the tank and do a carb rebuild, and a tune up. If that doesn't fix it, then I have no idea where to turn next.

ed & inge · 11-10-2009, 03:32 PM

hai,

i had the same problems some years ago.... boating slowly there was no problem, but above 1800/2000 rpm there was a problem. at one moment i took the petrol filter off, turned it up side down in a big glass vase, and after a few minutes i saw the problem........there was too many water in filter, so the carbs sucked petrol and water at the same moment. i made my tank empty, filtered the petrol and installed an extra filter with a little glass in wich i could look and my problem was over.

i hope you understand what i wrote down (i am from the netherlands so don't speak english like you all do)

good luck with finding the problem, ed

seapuppy · 11-10-2009, 04:31 PM

Ed...I got it and I'm italian!! :mrgreen:

SP :hello:

Watered down · 11-10-2009, 07:17 PM

I got it! but I think boaters speak some kind of universal language!

ed & inge · 11-10-2009, 08:51 PM

as long as you all understand what this cheese head from holland means it's oke to me.... :mrgreen: :mrgreen:..... i'll hope mr watered down that what i wrote down is your problem, good luck with finding it.

and for sea puppy.....ciao ciao..... :P :P

greatz from a wet wet wet and cold holland at the other side of the world (WISHING IT WAS APRIL 2010)