..but it ran 2 weeks ago...

Joined
Oct 17, 2014
Messages
14
I have an 87 Mercury 115 inline 6 and can't seem to get it to run longer than 5 seconds when stone cold, has been setting a few hours,TURN the key to on,hear the click,crank a few seconds and it sputters to about 1100 rpm then dies (yes,I squeezed the primer bulb till hard at beginning )hand throttle out of gear,try again,and it will catch a little like it wants to start,does this a few times usually kicking the starter out,then it will just crank and do nothing,but kill the battery.Tried this with my truck hooked to the battery with jumper cables and same thing.tried squeezing primer bulb in between cranking and bulb has little to no resistance.The thing is that it ran good for about 5 minutes 2 weeks ago on the muffs,(haven't put the boat in the water yet)in fact i started it twice in 10 minutes then and took a video of it on my iphone.the only reason it stopped was cause i shut it off.So,after that i started buying stuff for the boat,like a new tach,the old one was stuck at 5000,and added a fuel/water separator, a new primer bulb,clear fuel line and gear clamps on all connections.If it was sucking air,i think i would be able to see it.All new crossfire plugs (those were on it before) I tested the enricher by removing the hose on the bottom and turning on the key,fuel comes out in a stream.The key says push to choke but cant push it in,took the remote off and saw the ignition had been replaced by PO,but was wired correctly.just no push to choke feature.I will add a push button for this later.
The only thing is i havent changed out the fuel because it ran fine on it a few weeks ago.
If i stick a screwdriver into one of the carb throats to open the venturi plates it started right up but races so i shut it off before i damaged the engine
I have a limited knowledge of these engines and have scoured the forums for this problem to no avail.Im
 

houli

Recruit
Joined
Aug 24, 2015
Messages
1
Did you install the primer bulb in the correct direction? There is an arrow on them and should be pointed toward the engine. Check it and the fuel water separator for proper flow direction. Did you use any elbows when installing the separator or additional lines?

Cheers!
 
Joined
Oct 17, 2014
Messages
14
Did you install the primer bulb in the correct direction? There is an arrow on them and should be pointed toward the engine. Check it and the fuel water separator for proper flow direction. Did you use any elbows when installing the separator or additional lines?

Cheers!

Naw I double checked that filter and primer bulb are heading in the right direction, the bottom carb will drip fuel after a while, but thanks for the advice
 

DavidMoore

Petty Officer 2nd Class
Joined
Jun 2, 2015
Messages
183
Sounds to me like flooding, gas should not be dripping out the bottom carb.
A strip and clean of the carbs would be my way forward.

Interesting that when you just turn the key fuel comes from the enricher, on a push to choke engine this should not happen. How will the "choke" will never come off?.
Are you sure you dont have an auto enricher? In which case you don't need the push to choke on the remote control.
 
Joined
Oct 17, 2014
Messages
14
Sounds to me like flooding, gas should not be dripping out the bottom carb.
A strip and clean of the carbs would be my way forward.

Interesting that when you just turn the key fuel comes from the enricher, on a push to choke engine this should not happen. How will the "choke" will never come off?.
Are you sure you dont have an auto enricher? In which case you don't need the push to choke on the remote control.
The remote itself has the words " push key to choke" but you cannot push the key in in any position.This led me to believe there was something wrong with the key switch.I removed the remote and opened up the key switch,it had been changed recently by the previous owner , I could tell because the wiring was just looped around the screws.I installed spade terminals.and double checked the wiring was correct by looking it up online.
So you are saying The enricher selonoid doesn't need a switch,I left the key on for a few minutes and noticed the thing got warm.I was thinking of installing a push button for it but if it's automatic then I shouldn't need one.
The carb removal looks intimidating as there isn't much real estate in there,I have torn down carbs before,the secret is to do it all in a cloth lined box cause some of those parts can jump.
Can I just get by soaking the carbs in gum out over a few days or is a complete teardown necessary ?
 

DavidMoore

Petty Officer 2nd Class
Joined
Jun 2, 2015
Messages
183
There are 2 types of enricher:
- a manual one where you push in the key to operate, as soon as the engine fires you release the key, if the engine stutters a bit you can just give the key a jab inwards to give a extra squirt of gas and keep the engine running until it stabilses.

- Then there is the automatic that will squirt as soon as you turn the key, the automatic enricher is controlled by a heater powered from the stator windings.

Sounds like your is automatic so you don't need to push anything to choke. You could post a photo

You are moving the throttle into the fast idle position before starting? - On some controls there is a lever that is lifted up (to about 50% of far as it will go). On others, pushing a button located in the hub of the throttle lever allows you to advance the throttle without engaging forward gear.
Always cold start with some fast idle and bring the revs down using the apropriate lever.

Unfortunately you can't properly clean a carb without stripping it down, for your suspected flooding you will need to check your float levels and that the inlet needle is seating properly.
 

FMan

Cadet
Joined
Aug 11, 2015
Messages
11
Sounds like my engine is having a similar problem. The difference is that I'm getting the gas running out of the middle carb instead of the bottom. Looks like I'll be tearing down and cleaning the carburetors. My biggest trepidation is adjusting them after reassembling them.
 
Joined
Oct 17, 2014
Messages
14
Sounds like my engine is having a similar problem. The difference is that I'm getting the gas running out of the middle carb instead of the bottom. Looks like I'll be tearing down and cleaning the carburetors. My biggest trepidation is adjusting them after reassembling them.
Amen to that.
 

DavidMoore

Petty Officer 2nd Class
Joined
Jun 2, 2015
Messages
183
I was too until I did it for the first time, I found out it's not as difficult as you might think.
A service manual will take you through step by step.

I can't help with specific's because my engine has different carb's than yours, but you could make another post and ask for advise.
 

FMan

Cadet
Joined
Aug 11, 2015
Messages
11
Do you have a particular sevice manual you would recommend? I've heard both good and bad (more bad) about the Seloc manuals. However, I've never had opportunity to look at one myself.
 

DavidMoore

Petty Officer 2nd Class
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Jun 2, 2015
Messages
183
I have the Merc manual because it came with the boat, I would definately recommend it even at the extra money.
Just be sure to get the one specific to your serial number.
 
Joined
Oct 17, 2014
Messages
14
Just wondering if it's the new tachometer I installed as it ran fine before I put it in,I didn't try starting it immediately after installing , it was a few days later,and haven't had time to tinker on it lately as my new job has me gone 14 hours a day,hardly time for dinner and sleep but I will unhook the send wire on the tach and try it.
What would that tell me if it runs with that wire removed? I wired it up just like the old one ( which was stuck at 4600)
 

FMan

Cadet
Joined
Aug 11, 2015
Messages
11
I wouldn't imagine that the tachometer would leave you with fuel running out of the carbs. If your engine does run with the new one removed, it might tell you that the old one was wired wrong (possibly why it was stuck at 4600 rpms?) It's worth taking a shot, though I don't think the tach would be the cause of the motor deciding not to run. However, you may prove me wrong. It could be shorting something out.
 

jsalz

Petty Officer 2nd Class
Joined
Jun 12, 2008
Messages
103
I'm no expert but if it were me, I'd be sure I was getting a good spark. Not familiar with your motor but I'd be checking electrical. There's a how to on this site I used to check spark on my old motor. Turned out two of the 3 coils were bad. Just some ideas. Good luck
 
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