3.0lx no start after base timing

[fngboater]

I just finished rebuilding my motor and put it in the boat. It started right away no problem after installing the distributor. I hooked up the timing light, put the dist in base mode by jumping the two white wires together and bypassing the shift interupt switch by hooking the two wires together. I was able to set the timing to 1* btc. it idled and reved pretty darn (i could tell it needed some advance as i reved it ).so i turned it off and removed the dist jumper wire . my problem is after taking it out of base time mode it didnt want to start. anyone ever had this problem? put the jumper wire back on and it fires right up and reves and idles darn good. is it advancing to much without the jumper wire connected? does the dist have a mechanical advance also? can my timing light be giving me problems? there is no advance knob on the gun so i know its not that.

motor is a 96 3.0lx mercruiser with est ignition firing order is correct 1342 and so is the rotation of the dist

 

[Bt Doctur]

Re: 3.0lx no start after base timing

Try this link , makes no mention of jumpimg the shift interuptor http://www.marinemechanic.com/site/page229.html

 

[fngboater]

Re: 3.0lx no start after base timing

so where can i get one of those adapters? I thought i only needed the jumper on the two white wires as per the downloaded service manual number 14

 

[Don S]

Re: 3.0lx no start after base timing

You don't need that adapter for the Mercruiser engines, and yes you bypass the shift interrupt switch on the 3.0L.

After you set the timing, with the engine off, you remove the jumper and reconnect the shift interrupt switch.

When you set the timing, was the engine running when your bypassed the shift interrupt switch and jumpered the 2 white wires?

Manual 14 is for the drive, and has nothing to do with setting the timing of your engine.
Here is a link to manual 13, which is for your engine http://www.4shared.com/document/B3wzU5Iz/Service_Manual_13.html

 

[Don S]

Re: 3.0lx no start after base timing

Here is some information from a newer manual with more details on timing the 3.0 engines. Just use your specs. http://www.4shared.com/office/7ubgWxzR/30_EST_timing.html

 

[fishrdan]

Re: 3.0lx no start after base timing

2

and bypassing the shift interupt switch by hooking the two wires together.

Did you reconnect the shift interrupt, undo the jumpering of the shift interrupt wires. If no, the dist sees the shift interrupt switch being tripped and kills the ignition.

 

[Don S]

Re: 3.0lx no start after base timing

2

Did you reconnect the shift interrupt, undo the jumpering of the shift interrupt wires. If no, the dist sees the shift interrupt switch being tripped and kills the ignition.

Not exactly on an EST. What it does do, is puts power to the distributor and locks the distributor into base timing mode. If the engine is not running, it could make it very hard to start.

 

[achris]

Re: 3.0lx no start after base timing

Did you reconnect the shift interrupt, undo the jumpering of the shift interrupt wires. If no, the dist sees the shift interrupt switch being tripped and kills the ignition.

That's what I was going to say.....

 

[fishrdan]

Re: 3.0lx no start after base timing

Not exactly on an EST. What it does do, is puts power to the distributor and locks the distributor into base timing mode. If the engine is not running, it could make it very hard to start.

I though he had it timed, turned the engine off, removed the dist (white wires) jumper, but forgot to un-jumper the shift interrupter switch wiring? Leaving the shift interrupt wires jumpered would kill the ignition.

 

[Don S]

Re: 3.0lx no start after base timing

Leaving the shift interrupt wires jumpered would kill the ignition.

It does not kill the ignition as it does in points or Thunderbolt ignitions, it just locks the timing. If it killed the ignition, it wouldn't keep running when you jumper it when the engine is running. If one was bypass the other ignitions like that, it would kill the spark by grounding out the ignitions. On the EST ignition especially the 3.0L engines, it would throw the timing off about 12? to 14? and make it very hard to start, but he would still have spark. On a V8 engine, there is very little difference in base timing and normal timing, and would probably start, just wouldn't advance.

 

[fngboater]

Re: 3.0lx no start after base timing

You don't need that adapter for the Mercruiser engines, and yes you bypass the shift interrupt switch on the 3.0L.

After you set the timing, with the engine off, you remove the jumper and reconnect the shift interrupt switch.

When you set the timing, was the engine running when your bypassed the shift interrupt switch and jumpered the 2 white wires?

Manual 14 is for the drive, and has nothing to do with setting the timing of your engine.
Here is a link to manual 13, which is for your engine http://www.4shared.com/document/B3wzU5Iz/Service_Manual_13.html

sorry for the delay...i said manual 14 but i really meant 13 ..my mistake
i already had the jumpers connected and shift interupt connected before i started it up. Will that effect it.

i figured the bypassing the shift interupt would be helpful to me since my shifter isnt adjusted corectly yet

also im sure it doesnt matter but the upper and lower unit of the drive are off the boat. Only the gimbal is there right now

 

[fishrdan]

Re: 3.0lx no start after base timing

It does not kill the ignition as it does in points or Thunderbolt ignitions, it just locks the timing. If it killed the ignition, it wouldn't keep running when you jumper it when the engine is running.

Hmm, I can tell we are disagreeing here (AKA locking horns), but the 3.0L EST will kill the ignition if the shift interrupt wires are shorted together... UNLESS, the white wires on the dist are shorted together first, then it will drop the EST dist into base timing mode.


I have first hand experience with this as my lower cable shift went bad and I couldn't get the drive into gear, every time I shifted into gear it killed the engine. I had to disconnect the shift interrupt wires, shift it into drive and get my butt back to the landing ASAP,,, shutting off the engine was the only was to get it out of gear, not fun. I replaced the lower shift cable and everything was A'OK.

FNG, either reconnect the shift interrupt wires or just leave them disconnected (tape them up, 12V is present) until you get the shift interrupt adjusted properly.

 

[Don S]

Re: 3.0lx no start after base timing

UNLESS, the white wires on the dist are shorted together first, then it will drop the EST dist into base timing mode.

I was wrong, my mind was not taking into account the white wires not being bypassed at the same time.. Sorry about that :redface:

 

[fishrdan]

Re: 3.0lx no start after base timing

Eh, no problem there Don. Happens to the best of us. 1 out of a million, we can live with that.

 

[fngboater]

Re: 3.0lx no start after base timing

FNG, either reconnect the shift interrupt wires or just leave them disconnected (tape them up, 12V is present) until you get the shift interrupt adjusted properly.

10-4 i will do both lol. so should i hook up the dist jumper wire while the engine is running? and then disconnect it after i set timing, while running?

another question... since there is no mechanical advance it wouldnt matter if it idles a little high while setting the timing right.

 

[achris]

Re: 3.0lx no start after base timing

...another question... since there is no mechanical advance it wouldnt matter if it idles a little high while setting the timing right.

Yes, it does matter.... The advance is done electronically, based on the engine speed. If the engine's running fast, the electronics will advance it... You need to set the timing at the specified idle speed.

 

[fngboater]

Re: 3.0lx no start after base timing

Yes, it does matter.... The advance is done electronically, based on the engine speed. If the engine's running fast, the electronics will advance it... You need to set the timing at the specified idle speed.

ok im not doubting you but i thought when you put it in base timing mode it locks the timing so to speak.


anyways an update to what i have done now. I started the engine normally. while running i connected the dist jumper to the two white wires. then i unhooked the shift interupt switch and left them hanging(like what fisherdan said i could do.) i adjusted my timing to 1* btdc. i then unhooked the jumper wire from the dist. nothing changed.(like on a car with a vacuum advance the rpms change when you attach and remove the vacuum line) the timing just stayed the same. even while reving it maybe went to about 3* btdc. no advance.
i tried again... started the engine...installed the jumper wire at the dist then tried to bypass the shift interupt switch and hook those two wires together it tried to stall the motor and had a slight carb pop(like maybe it was really retarding or advancing the timing).
it seems to me that i never got it into base timing mode and i set the timing with the advance enabled .so now when i try and put it into base timing mode it tries to retard it to far and stalls.


wow see what happens when i actually "think about it" lol. sounds like a good name for a boat.

 

[fishrdan]

Re: 3.0lx no start after base timing

it seems to me that i never got it into base timing mode and i set the timing with the advance enabled .so now when i try and put it into base timing mode it tries to retard it to far and stalls.

That sounds right, you'll need to advance the dist a bit so it doesn't die going into base timing mode. Try setting it to about 12* without the dist in base timing mode to get it ball parked, then time the engine per the manual, basically...

1- start engine and bring up to operating temp
2- jumper the 2 white dist wires together
3- jumper the shift interrupt wires (engine will drop timing and RPM when it goes into base timing mode)
4- set timing to spec and re-check after tightening dist clamp bolt
5- reconnect shift interrupt wires to the switch/harness
6- unjumper dist white wires
7- check for timing advance

I agree with achris, time the engine with the engine at idle RPM, something like 600-750RPM. It's the only way I've ever seen/read/done engine timing. The EST might (might)time the engine over idle (1000+RPM), but I've never seen reference to that. I wouldn't trust the timing unless it is set at idle. If you have to set timing at over idle RPM, go back after getting the engine idling at the proper RPM, and double check the timing.

 

[fngboater]

Re: 3.0lx no start after base timing

ok its official im an idiot. i was able to advance the timing to around 12* btdc before putting into base timing mode so it would stay running. adjusted back down to 1*btdc. lowered the idle to about 700-800 rpms and the timing still checked out. adjusted the carb some, adjusted the valve lash and now she's purrin better than before. even starts up first crank and goes straight to a smooth idle.

thanks guys \

now its time to align the motor and then start going through the outdrive

 

[RR24]

Re: 3.0lx no start after base timing

fngboater how did you keep it cool without the out drive installed? also could the timing be set to 12 deg. right off the bat to get the cam and lifter's broke in, then set the timing the way i should be after break in?

Thanks Wes