4.3 Mercrusier Timing Mark

[dcf1999]

I seen this posted in the past forum but it didn't quite answer my question. I have a 03 Fourwinns with a 4.3 mercruiser (thunderbolt ignition). I'm looking at timing the engine; however I cannot find the timing tab. I see the one line on the balancer but no "tab" on the engine. I could have sworn I've seen one there before (a tab). The only thing I see is a chuck of metal (looks like it's cast in) with a V cut into it, but no tab with different lines (or degrees) on it. Could the tab have fallen off? If so, is there something I can do to correctly time the engine. I attached some pictures.

Also the purple/white wire in the picture? is that the wire used to put it into base timing mode? The black ?spade? terminal next to it? could I use that as a ground to hook up the purple/white wire to.

I attached 4 pictures. One shows the general engine (for identification purposes), another one shows the wires in question, the third one shows what I think is the timing mark on the balancer (just making sure it is), the last shows the ?tab?.

Just a side note... I have never timed an engine before but understand the concept. I'm pretty mechanically inclined as I've rebuilt automotive engines and transmissions so I'm pretty sure I can tackle the whole timing thing. I do own the mercury factory service manual for that engine.

Thank You.

 

[Don S]

Re: 4.3 Mercrusier Timing Mark

There is only the notch in the timing cover and the line on the balancer. When lined up they are at 0? TDC.
Most people just use a variable timing light to get the proper degrees when timing.
Merc also makes a degree sticker for the pulley, so does speed shops, you just need to get one for the proper diameter of your balancer.

 

[dcf1999]

Re: 4.3 Mercrusier Timing Mark

ok.. sweet.. so my next question is that on the timing light (does allow for timing advance), there should be an adjustment to set it to 10 deg BTDC and when the light shines on those marks it's correctly set? I've never timed an engine before but understand the basic concept. All the engines I've worked on (mostly automotive) i've never needed to time.

 

[dcf1999]

Re: 4.3 Mercrusier Timing Mark

Now that you said something about the sticker, I do recall there being some sticker on the balancer where that timing mark is. Can't remember what it looked like. It's gone now and all you can see is the left over adheasive. Should I order a new one or just not worry about it.

 

[Don S]

Re: 4.3 Mercrusier Timing Mark

All the engines I've worked on (mostly automotive) i've never needed to time.

You shouldn't have to time this one either unless the distributor was removed, or loosened and turned.

You can get the timing decal if you want it, it's up to you. Get one from your local Merc dealer.

 

[dcf1999]

Re: 4.3 Mercrusier Timing Mark

I just want to check it. Last time it was at the marina was for warranty, they adjusted the timing and it just never ran as well as it did before I took it in. I've had problems with that marina before... like not installing the mount bolts after aligning the engine.... And after that instance, I've never took it back. I prefer to do everything (alignment, water pump, etc...) myself now... just don't trust other people with my stuff...

I understand that once the timing is set on it, it shouldn?t change unless the distributor was moved (which I guess it was when I took it in to the marina)... I just want to feel good that it was set right by the goofs at the marina in the first place. Plus the service manual (page 1B-4) says the timing should be checked every year. Basically I just finishing doing a bunch of work (alignment, water pump, and tune up) and the timing is last thing I want to check before summer.

That purple/white wire in the picture I uploaded? is that the wire to put it in base-timing mode?

 

[Eric 3.7LX Alpha 1]

Re: 4.3 Mercrusier Timing Mark

Here's a pic of a craftsman advanced timing light which is a dino. compared to the digital models today. Turn the dial until the marks line up and that's what the engine timing is.

If it's off, set the dial to what you want the timing to be, and rotate the distributor slightly one way or the other to get your marks to align at the new setting.