Why My evinrude RACE at Idel

I got 1998 Evinrude 200Hp 90 degree laitly it got my attention to few things that not sure about so I need some thoughts and Help , first of all the Eng start right up great and idle using the hose @ 1200-1300 RPMS but never slow down to like 1000-1100 after it gets warm compare it to another Eng which my friend got, However it slow it self down once but it spike right back up .. Can't re-call the functions were it suppose to slow it self down after it reach a certain operating temp...? And stay at that Rpm.


So here is my 2 issues...My last trip I trolled plenty of time at low speed my trolling was just in gear , I noticed by the end of the trip that the idle wasn't smooth, it idle sluggish then some sneezing or hiccup .then she dies, she start right up, idle smooth for little then all over again , but when am ready to hit the gas she picks up an go smooth, I looked at the plugs and they seems wet so I cleaned them and went out today but didn't troll but ran low speed and crossed around , in the way back heading to the dock we slowed down then I did I del to get ready , Boat started to idle sluggish then died but started back up and we docked with no trouble, I watched at I del and noticed when she get that sneeze /hiccup an extra puff of smoke shot out ..Is this sound like I fouled the plugs Since it never did it before tell I got back from my long trolling trip??

My 2nd issue is the idle?? when I got back today to flush the Eng , I connect the hose it start right up but the RPM shoot up to 1500 , It attempted to droop the Rpm?s and slow it self but it never it stayed that way , instead it went back to 1500 and never slowed down tell I turned it off ?considering at this point eng was running all day ?.Any thought , ideas ?

Re: Why My evinrude RACE at Idel

I think you might have an air leak in your fuel system some where which is causing the motor to race while idling. Have you notcied any fuel leaks, even a tiny one? B/c if you have fuel leaks, then you have air leaks, which means your starting and idle will get wacky quick. Just a guess.

Re: Why My evinrude RACE at Idel

air leak and fuel leak are two completely different things, and air leak will cause high idle for sure, fuel leak may cause a fire, and excess fuel use, but usually not fast idle!

Re: Why My evinrude RACE at Idel

No fuel leak noticed at the Tanks, I got 2 tanks built in the boat , I got one serviced a few weeks ago & am ready to do the 2nd , this issue been going on for a While now I just decided to take it farther this time than just listen to it...If it's an air leak should I start from the Motor ...?

Quick Start option that function where the Eng lower the rpms after it warms up and get to the proper operating Temp ... ?

Reading the CDI doc ..Found that i could possibly have a faulty temp sensor that won?t register the temp of the block at any point therefore it will not send the signal to the Power pack to lower the RPMS when it reach the correct temp...testing the lead will rule out this. ...Is this sound possible

What about the 1st idling issue ....?

Re: Why My evinrude RACE at Idel

you need to check the very basics first, do you have a genuine manual for the motor? if not, get one, it could be as simple as adjustments, do not start pulling things to bits just yet! or you may have another fault to find. Forget the electrics just yet.

Re: Why My evinrude RACE at Idel

Running on a hose, with no backpressure against the exhaust, makes the motor run leaner and thus faster. It is normal to idle about 1100-1500 with your motor on a flusher. In the water, the carb idle circuits are calibrated for the backpressure and the motor should idle close to 900-1000 in neutral and 650-750 in fwd. gear. Most tachometers are not that accurate at low rpms and that is why a shop tach is recommeded for setting the idle rpm.

Re: Why My evinrude RACE at Idel

Eng idle around 900-1000 with backpressure ( in the water) you can't even hear it running, The issue am after or trying to understand when it is on the flusher, I had a 130hp prior to this with quick start that after running it ,You can tell that rpms drooped and the quick start got disabled ..!!

I got a friend with 150HP 97 60 Degree that got quick start that function well..

Re: Why My evinrude RACE at Idel

QuickStart does not work above 1100 rpm, so your high idle on a hose does not allow QuickStart to do its thing. If it works fine in the water as the motor warms up, then you are OK.

Re: Why My evinrude RACE at Idel

seahorse5... Thank you for the info, I noticed the RPMS are much lower when I start it cold than when I come back from a trip... For example if I don't go out for almost a week, I like to run it on the hose for a few minute prior going out to make sure am good with no surprises at the dock ..So the Rpms seems lower but steady no fluctuation or at least not that much compare to when I get back it?s immediately up to 1400-1500 RPMS .....

I got to do some homework by looking under the cowl to see if I even got quick start on this Eng or not

What you think of the 1st issue is tackling with the Idle....?

Re: Why My evinrude RACE at Idel

The big V6's have had QuickStart since 1988.

Your sneeze at idle is due to being lean. It may need a carb adjustment, a sync and link adjustment, carb cleaning, stuck rings, and/or thermostats so the motor warms up enough - or all of the above.

Re: Why My evinrude RACE at Idel

FOUND 2 temp sensor one each side port /S-port. I pulled plugs they all burning about the same little wet but brown like they should no sign of any plugs running lean at all

Am going to check the thermostats as they prob never changed at all ...Maybe i got one stuck open

Re: Why My evinrude RACE at Idel

One of our local Mechanic advice me to Use the Evinrude Oil as it burn much cleaner and leave the plugs less wet than Pennzoil Marine XLF Synthetic blend which I have been using. It's about $11 difference per gallon ..I don't want to sacrifice any of the performance and hurt the Eng for few $$'s

could that be another factor contributing to it idle kind of sluggish
What's the input on that

Re: Why My evinrude RACE at Idel

I think that the oil you are using is fine.

Re: Why My evinrude RACE at Idel

Pulled thermostat out and tested them hot and cold ...Result One gets open and expand farther & faster than the other however the cooling test show one get half way close vs. the other ...Time to replace.

2nd I was working to check my 'check circulation valves' to check for carbon clogs and noticed the Aluminum plait mounted on the intake where the carb bolt right on I can see the lower outside bolt about ready to come off, Which could explain the high RPMS or the hiccups as it might be sucking extra air than it should..So i made it tight..No clogs by my circulation valve s-port side..Will check the port side and install new thermostats

There one q ..Is that finding of the non tight bolt leaving that gap between the alum plait & intake enough to cause this hiccup /sneeze

Re: Why My evinrude RACE at Idel

Yes!

Re: Why My evinrude RACE at Idel

noelm said:

Yes!

Click to expand...

After discovering that thermostat remain half stuck open on one bank the reason for it to run at high rpms bypassing the quickstart for the simple fact the temp sensor at this bank reading low temp and keep signaling the pack to rev high ...???? Or this just my guess

Re: Why My evinrude RACE at Idel

Only the port bank engine temperature controls the QuickStart below 1100 rpm.

Re: Why My evinrude RACE at Idel

seahorse5 said:

Only the port bank engine temperature controls the QuickStart below 1100 rpm.

Click to expand...

The thermostat associated with the port bank test show stuck open and will not close

Re: Why My evinrude RACE at Idel

Update...

Installed the new thermostat...I started the eng * Quickstart engaged and ran little high as it should, After few seconds could be little over a minute noticed the Quickstart got disabled & RPMS drooped to 1100 and am all

At the mean time Eng been winterized and hibernating for the winter,will find out the result of the little idle hiccup, glitch comes sprint time ...thanks for all your help