ignition not advancing - help!

[ECeptor]

The timing light just proved my 1989 330hp 454 with Thunderbolt IV (4) ignition is not advancing as the rpm's go up.
From what I've learned so far, my options are:
1) buy a new advance module - $320 from local dealer, week to get
2) hope to find a used module on ebay - $??? available ???
3) buy whole new system through Summitt - ~$250
4) hope my ***boat buddies can come through for me with a better option that the ones above!
So, am I right in thinking it's the advance module that has gone south? I've triple check all the wiring vs the manual and everything there is good. I have no idea how old the module is.
Advice, thoughts, opinions?

[Infomaniac]

Make sure the knock sensor is not keeping the timing from advancing.

[ECeptor]

Make sure the knock sensor is not keeping the timing from advancing.
Does the Thunderbolt IV have a knock sensor? I thought that feature was on the Tb V only.
I'll double check the manual...but when I checked wiring there was no knock sensor on the schematic.

[Infomaniac]

I don't know for sure man. I think my friend's Fountain HP 500's had a knock sensor and was IV.
Just throwin some stuff out to consider.

[Blown 472]

Speaking of timming, my buddy has a carbed 502 in his boat, bravo drive. What should the total timming be on that motor?

[ECeptor]

I don't know for sure man. I think my friend's Fountain HP 500's had a knock sensor and was IV.
Just throwin some stuff out to consider.
I appreciate all the advice I can get! I'll check the manual again tonight just to make sure.
BTW, I'll be down near your neck of the woods tomorrow - Kaw lake. Leaving my sick rig at home and going with some friends for a nice social day on the water.

[Infomaniac]

Mrs. Infomanic and I are going to the Boat races tomorrow. Get our fill of nitro boats. :smile:

[ECeptor]

Speaking of timming, my buddy has a carbed 502 in his boat, bravo drive. What should the total timming be on that motor?
1994 and older 502mag is 28° BTDC @ 5,000rpm according to my Merc manual. Not sure what the spec is on newer 502s.

[ECeptor]

Mrs. Infomanic and I are going to the Boat races tomorrow. Get our fill of nitro boats. :smile:
Which lake?

[Blown 472]

I think it is a 94, thanks. So if it doesn't advance it is not in the dist?

[Infomaniac]

Which lake?
Oklahoma City. Smack downtown. On I-35 just south of I 40 Sheridan exit. First one there. Big turn out. Been talking to a few guys that were there today testing and tuning.

[ECeptor]

I think it is a 94, thanks. So if it doesn't advance it is not in the dist?
Advance is controlled by a separte module they call the "ignition amplifier" in the manual.

[ECeptor]

Oklahoma City. Smack downtown. On I-35 just south of I 40 Sheridan exit. First one there. Big turn out. Been talking to a few guys that were there today testing and tuning.
Sounds like a good time...would be fun to check out. But tomorrow is a chill out, ski a little, socialize alot day on the water. No nitro involved!

[Blown 472]

Advance is controlled by a separte module they call the "ignition amplifier" in the manual.
Is that the mercathorp thing by the carb??

[ECeptor]

Is that the mercathorp thing by the carb??
Nope. It say's "Thunderbolt" on it and is bolted to the inside of the port exhaust riser (on my engine at least).

[ECeptor]

anyone know if this is a good price?
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4560865829&category=31284&sspagename=WDVW
I know my local dealer is a rip-off so what the quoted me isn't much help.

[BOBALOO]

See if you can borrow an advance module from somebody. there are no advance weights in the Thunderbolt 1V or V dist. The TB V has a knock sensor and was introduced in 1995/96. I have the TB V and it's on a 96 454 mag carbureted engine.
The 100$ one on ebay is about right and if you search OffshoreOnly.com you will find alot of info on them. You should be able to find one on OSO if you post a thread there with your question.
Oh yeah, the one on ebay is for a V8 and has 22* of advance built in. you will have to turn the dist to get the total you want.
**********IF you hurry there is a 24* one on ebay for 49.95 buy it now***** Great price if it works

[BOBALOO]

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=31284&item=4560931594&rd=1

[ECeptor]

**********IF you hurry there is a 24* one on ebay for 49.95 buy it now***** Great price if it works
On somethink like this, I'd pay the premium for a new part. Used, unless it's dirt cheap, isn't the way to go, imho. BUT, I appreciate the heads up!!!

[19cobaltcd]

Try giving JD a call at Kansas Marine Parts. His number is 540-9986. He used to be in Haysville but moved out to Mt Vernon just off 54 hwy past Cheney. He can order alot of aftermarket parts and can usually have them in a day or two. And his price is worth the trip out there normally. He can be hard to get ahold of but leave a message and he will get back to you. Tell him blondie sent you.

[ECeptor]

Try giving JD a call at Kansas Marine Parts. His number is 540-9986. He used to be in Haysville but moved out to Mt Vernon just off 54 hwy past Cheney. He can order alot of aftermarket parts and can usually have them in a day or two. And his price is worth the trip out there normally. He can be hard to get ahold of but leave a message and he will get back to you. Tell him blondie sent you.
Thanks for the contact! I'll call him first thing tomorrow.

[ECeptor]

After calling about 10 different places, I found 0 used modules and only 1 new one in stock and they were asking $337 for it.
So, I bought this one instead - http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4560865829&category=31284&sspagename=WDVW
I'm hoping it get's here in time for the weekend! Even if I lose a weekend, I saved $200 vs the best dealer price...