86 Merc 115 stalls when trying to engage it in gear

[aljero]

My buddy has an 86 115 merc, runs on idle "barely" but completely stalls when u try n shift it in gear! 135psi on all 6, good fuel in the tank, carbs were just cleaned! could it be the timer base trigger??

[flabum1017]

Check the spark, need to check the basics first....... could be a bad spark plug or two, plug wires, coils, switchbox, timer base, stator, mis-adjusted carbs, reeds etc...............

[aljero]

Yes, he put new plugs in, all the electronics are new except the timer base trigger and stator, the switch box was replaced by a tech last summer, I checked for spark as well and all cylinders were hot! Its a strange problem!

[aljero]

It does seem to loose a cylinder on idle, but then it kicks in! my guess is its definitely electrical!

[flabum1017]

check all the grounds and connections

[aljero]

Yea, I'll double check his connections! I really appreciate your help! This things got me goin nuts

[davemvegas]

i had merc 4cly last year and after buying parts to fix non firing cyls i read that it is made to run on two cyls untill 2200 rpms.i know this sounds stupid but that is what manuel states.if one of the 2 cyls it idles on has problem it wont idle on one cly. not sure if your 87 115 is a 4 cly or not but just something to google for info to see if yours has any dumb fuel saving ideas that suck.

[aljero]

No this things n old school 2 stroker Dave, yea I hear a lot of people complain about those smart start systems! Nothin but more electronic parts to fail is what they are

[gregpro50]

If it just barely runs at idle why not just kick up the idle to the specified rpm?

Also make sure the idle mixture screws are adjusted right. It may be running to lean at idle.

You'll also want to check the timing.

[flabum1017]

No this things n old school 2 stroker Dave, yea I hear a lot of people complain about those smart start systems! Nothin but more electronic parts to fail is what they are

He said 4 cylinder, not 4 stroke ,

[flabum1017]

i had merc 4cly last year and after buying parts to fix non firing cyls i read that it is made to run on two cyls untill 2200 rpms.i know this sounds stupid but that is what manuel states.if one of the 2 cyls it idles on has problem it wont idle on one cly. not sure if your 87 115 is a 4 cly or not but just something to google for info to see if yours has any dumb fuel saving ideas that suck.

He said he has good compression on all six

[gregpro50]

The 4 cyl 115's with the 2+2 ignition is an entirely different animal. This one is an inline 6.

[CrayzKirk]

Just FYI... I spent the last three weekends working on an 85 75hp L4 that I was convinced the electronics were faulty on. I had rebuilt the carbs and boy did it idle great on the hose. Put it in the water and it would just die. After much cussing and hours spent testing the electronics, I opened the idle screws another 1/4 turn each and the motor started idling in the water. Idles like crap on the hose. If the motor has the idle stabilizer, try removing it. Now as a rough setting on the hose, I get the motor to idle fairly well and then open each idle screw another 1/4 to 1/2 turn before putting it in the water.

Not an L6 however it is direct charged and has very similar electronics. ESI makes a good DVA adapter for about $40 shipped. ESI-640 works in most standard meters.

Kirk S.

[aljero]

Much appreciation here for all of the input from you guys, I will re adjust the carbs n check all the connections n see what happens!!! Hopefully it is something simple!! Thanks guys

[delawarerick]

When you cleaned the carbs did you clean the idle circuit we had gunk in the bottom carb low speed jet and it would not run idle or go in gear. Check also the fuel pump output just for giggles. When I had a pinhole it wouldn't idle and die with gas. Once right you will love that engine I beat my weeklyRick