advance timing question

[cooter2506]

Im going thru Dons WOT list and eveythign looks good except I dont think im advancing enough. At 2400 rpms(for only a few seconds) advance is only 15 degrees. Also I have a vacuum reading of 15. Which I beleive is retarded timing. I changed timing to 10 BTC. Still ot advancing more than 15. What should the advance be at 2400 rpm. 1998 5.0 mercruiser 2 barrel mercarb. Thanks Dean

 

[Don S]

Re: advance timing question

This is in your post

1998 5.0 mercruiser 2 barrel mercarb.

This is in your signature

1988 Chaparral 198 XL 5.0L

What do you have.?

 

[cooter2506]

Re: advance timing question

it is a 1998 engine in a 1988 boat

 

[Don S]

Re: advance timing question

Do you have an 88 Thunderbolt IV ignition or a 98 Thunderbolt V ignition system?

 

[cooter2506]

Re: advance timing question

98 thunderbolt 5

 

[cooter2506]

Re: advance timing question

Is it that bad that your writing me a book? LOL

 

[Don S]

Re: advance timing question

Here is the link to the oem service manual for your engine.
http://www-alt.mercurymarine.com/mnetdata/SERVICE/CRUISER/Servmanl/24/24covr1.pdf

Go to section 4B page 13 and you can see the graph for your advance. Looks like you are right about where you should be.

 

[cooter2506]

Re: advance timing question

Ok then I guess the oly thing left is the carb, Thanks Don. Oh yeah does the vacuum reading im getting look ok too?

 

[cooter2506]

Re: advance timing question

anyone have any ideas what vacuum should be and I looked at the link Don gave me for the advance curve. Seems to be low to me but he said it is ok. Im very frustrated with this engine. I guess only thing left is the carb.

 

[cooter2506]

Re: advance timing question

*Bump*

 

[Don S]

Re: advance timing question

I just re-read your original post, and maybe I am reading it wrong. I read it to mean your advance was 15? over idle setting. Now if you have it set to 10? and it's only increasing 5 more degrees to the 15? mark, then yes that is a problem and could be the ignition module.

 

[cooter2506]

Re: advance timing question

wow brand new ignition module last year, could it be te sensor at bottom of distributor?

 

[cooter2506]

Re: advance timing question

Here is the numbers off the module 5.0 LG-Alpha *861459-1*

 

[cooter2506]

Re: advance timing question

I just checked the continuity of my sensor and it is 5.345. Book says if it lower than 100ohms it needs replaced, so im assuming it is bad? Sorry for the ignorance but I am at my wits end on this thing and have done so much to it and nothing is working.

 

[cooter2506]

Re: advance timing question

Any opinions on this I need to get boat running right for our weekend trip to Raystown to do some skiing, lol not me but wife will ski. I wanna go fast enough to get her up and dump her, LOL

 

[cooter2506]

Re: advance timing question

*bump*

 

[cooter2506]

Re: advance timing question

I think I hijacked my own thread, LOL I just oredered the sensor. Hope that is it. Don, if you have any other ideas since the module is new let me know either way. Thanks(desperate) Dean

 

[cooter2506]

Re: advance timing question

I was hoping one of you experts would reassure me on my findings. And tell me if im doing the wrong thing or te right thing.

 

[Uraijit]

Re: advance timing question

No expert, but good luck!