72' 85 hp idles awesome, but dies when I relly open the throttle.

[INDYCAVER1]

Hey, I just took my boat out for the first time today. I did alot of work to the hull, but not much to the motor since i have had it. The motor runs fine when hooked to the hose. It will rev up in gear and run fine all through the rpm range in gear, but in the water under load, it stalls after I get it past about 2200 rpms. It runs great from idle to 2200 though. when i got it home i noticed one of the nuts holding one side of the carb on was really loose. Does anyone think that could have been my problem? I thought it could have been sucking in too much air since the carb was loose and starving for fuel when i really got into the throttle.

 

[kenmyfam]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

Could well be your problem and it is an easy one to try. Carb could well need a service though. Did you put fuel stabilizer in and run it through the motor before you winterized ?? if not the carb is probably gummed up. Give the carb a service and if still no luck give it a basic health check.
Compression
Spark
Fuel delivery
Spark plug condition.
Post results.
Welcome to iboats.

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

yes, i put stabilizer in before i parked it and completly ran it out of gas in the carbs. I also checked and cleaned up the plugs today also. they looked a little dirty, but not horrible. Is there a way to check it under load out of the water? Id hate to haul it 45 mins. to the lake just to have it in the water for another 20 mins. like today. I wish i lived closer so i could run it back and forth easily.

 

[SparkieBoat]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

if carbs are clean sounds like bad fuel pump. or bad fuel line/connection/tank vent/pickup

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

Is there usually a screen or filter on the pick up down in the tank too? I checked the screen before the fuel pump and it was clean, but i never though about inside the gas tank. I have a tank something like this http://www.overtons.com/modperl/pro...eller_Marine_Fuel_Tank&aID=601R2&merchID=4006 . Also what sould I look for on the tank vent. Just make sure its not plugged up?

 

[R.Johnson]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

Check that the ignition stator is going to full advance.

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

OK =, i GOT SOME things to check next time i go out. im to the point that i have to take it out and try it again. are there any tests i can do with the boat out on the water? also does anyone know if there is a rebuild kit for a 72 85 hp esl v4 motor fuel pump, my manual i have says it will have to be replaced if it is the problem.

 

[SparkieBoat]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

you should be able to rebuild that pump, or replace it with a rebuildable type...try pumping your bulb while running and see if it helps, this would indicate pump or leak/restriction.

 

[emdsapmgr]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

Make sure the carb butterflys are full open at full throttle. When you get to that 2000 rpm range, have someone constantly prime the bulb on the fuel hose. That forces extra fuel around the pump, directly into the fuel bowls. See how it runs.

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

ok, i never thought to pump the bulb. I will try that, and take the gas cap off to ensure the tank is plenty well vented. are there any additive i can put in the fuel to try and clean out the carbs. Id take them apart and clean them myself, but im afraid ill mess them up worse than they are already. Id like to to use the best carb cleaner first if anyone will think it might work.

 

[SparkieBoat]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

Sea Foam is a great additive..you can try using in a super concentrate this will also help de carb your engine .... add 1 can of sea foam to 1 gallon of premixed fuel..use a small portable gas tank..it will probably smoke like a train but will clean fuel system and engine.

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

ok, i heard that was good stuff, but was sure if it was good for this situation. Ill try it. Thanks for the help everyone. Ill keep you posted on results.

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

ok, two more questions is it best to do the seafoam in the water or do it with the motor hooked to the hose? second, i dont have any low speed or high speed needles to adjust. my manual says i should have low speed needles for adjustment. Is this strange? my manual is for a 71 instead of 72 johnson 85 hp, would that make a difference? If so, does anyone hace a 72 manual that could scan a copy of the carb breakdown for me?

 

[relocyo]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

you could inlieu of driving to water pucrchase a lagre rubbermaid trashcan to put the motor in to run tests with... al so big 50 gal plastic drums are available online... dunno if its cost effective for you but would save some time and energy... just an idea...

 

[Challenger84]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

I would love to hear the results to Sea Foaming your OB.
I will be doing it to mine as well!

Here is a link for more info about Sea Foam

http://www.seafoamsales.com/gasoline-engine-faqs.html

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

Ok, here is the status. I took it out today and yesterday. Yesterday it ran great up to 3300 rpm(5500 is recommended wot) then would sputter and stumble. I was told to try and choke it at wot to see if it ran better, so i took it out again today an it would run just over 4000 rpm and it wouldnt die at full throttle, but it would turn anymore rpms, but that was only with the choke on. I got the courage up to take the carbs off and try and clean them up. the high speed orfices were a bit clogged, but not totally plugged. i am hoping this is the reason the motor is not getting enough fuel to run wide open. Seeing as choking the motor helps it, would you say i can rule out a spark problem? Ill post again after i try it with the cleaned carbs.

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

Ok, Carbs were the problem. It runs like a dream now. I thought it was wierd it ran ok low speed, but what do i know. I ran it yesterday and today all over the lake. My motor says 5500 rpms at wot, and I can get just over 6100 with the hammer all the way down. I wont run it like that because
I fear it will eventually hurt the engine. Do you guys think i need a different prop to keep it under 5500, or is it normal to have throttle left at max rpm?

 

[bigpoppakdog]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

When I had WOT issues a few years ago on my 1970 115 evinrude I had a guy tell me why would they make it so you have a WOT setting if they didn't want you to use it? Made sense to me.

 

[SparkieBoat]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

you could go up one size in pitch if you want, but your motor probably performs very well like it is. 6000 RPM is fine for your motor..for long runs I would probably back off to around 5800 just to save gas.

 

[INDYCAVER1]

Re: 72' 85 hp idles awesome, but dies when I relly open the throttle.

Ok, Im glad to hear 6000 wont hurt it. I didnt think it would, you cant be too safe. I might get another prop eventually and keep the one I have now for spare. I would like to get the boat up to 35 mph, but 32 is ok i guess. You always want just a little bit more