what ignition system

wryork25

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Can someone help me with what ignition system I have based on my serial number, OF765981?

Part 2, is the Delco EST a good alternative? I am pretty sure my module is bad.
 

Bondo

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Can someone help me with what ignition system I have based on my serial number, OF765981?

Part 2, is the Delco EST a good alternative? I am pretty sure my module is bad.
Ayuh,..... Welcome Aboard,..... Yes, the Delco EST is a rock solid system,.....
 

Scott06

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Can someone help me with what ignition system I have based on my serial number, OF765981?

Part 2, is the Delco EST a good alternative? I am pretty sure my module is bad.
Hers a parts breakdown for your engine https://www.marineengine.com/parts/mercury_marine_parts/sn/OF765981


your original set up would have been a mercruiser thunderbolt V . This is a good system unless the ignition module die$… the delco est is a great system, OEM quality.will bolt in with minimal rewiring
 

wryork25

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Thanks for the info and opinions all! Everyone is always a help on here, very grateful for the assistance.
 

wryork25

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OK everyone, I am still trying to figure out this spark issue. per procedure about mid way down it states to disconnect the coil wire from top of the dizzy and connect a spark gap tester. then disconnect the white green wire from the dizzy and tap on ground. Look for spark at gap tester.

I dont have a gap tester, can I just use a spark plug with ground on the threads?
 

Bondo

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OK everyone, I am still trying to figure out this spark issue. per procedure about mid way down it states to disconnect the coil wire from top of the dizzy and connect a spark gap tester. then disconnect the white green wire from the dizzy and tap on ground. Look for spark at gap tester.

I dont have a gap tester, can I just use a spark plug with ground on the threads?
Ayuh,.... That should work,....
 

wryork25

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Does anyone have any recommendations on where to buy a Delco EST if my module is bad? I am not sure if this violates rule 8? I am just looking for a reputable source.
 
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Bondo

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Ayuh,..... The place you see in the rule 8 violation thread is a quality supplier,....
Btw, the violation was for asking posters if They had one to sell, as it appears to be a Nla part, not asking where to find one,....
Btw 2, the forum rules are posted at the top of the main forum,..... ;)
 

wryork25

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Hers a parts breakdown for your engine https://www.marineengine.com/parts/mercury_marine_parts/sn/OF765981


your original set up would have been a mercruiser thunderbolt V . This is a good system unless the ignition module die$… the delco est is a great system, OEM quality.will bolt in with minimal rewiring
This ma
Hers a parts breakdown for your engine https://www.marineengine.com/parts/mercury_marine_parts/sn/OF765981


your original set up would have been a mercruiser thunderbolt V . This is a good system unless the ignition module die$… the delco est is a great system, OEM quality.will bolt in with minimal rewiring
 

wryork25

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Scott, this may be a dumb question but could you tell me which manual is the correct one for this motor? Is it the Mercury Mercruiser #24 Service Manual - Marine Engines GM V-8 305 CID (5.0L) / 350 CID (5.7L) ?
Hers a parts breakdown for your engine https://www.marineengine.com/parts/mercury_marine_parts/sn/OF765981


your original set up would have been a mercruiser thunderbolt V . This is a good system unless the ignition module die$… the delco est is a great system, OEM quality.will bolt in with minimal rewiring
S
 

wryork25

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Could someone please tell me what the correct service manual is for my motor.

Mercruiser (5.7l / Lx 350 Mag Alpha serial number OF765981​

 

Scott06

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Scott, this may be a dumb question but could you tell me which manual is the correct one for this motor? Is it the Mercury Mercruiser #24 Service Manual - Marine Engines GM V-8 305 CID (5.0L) / 350 CID (5.7L) ?

S
I dont know - you may want to call merc tech support and give them your serial

Maybe @alldodge or @Bondo knows

serial number is OF765981
 

alldodge

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Serial number 0F765981 is manual 17 covering 305 and 350 1993-1997
Part number 8232251
 

wryork25

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I did go through the troubleshooting chart but I think I may have made a bad assumption. I got to the step of spark testing the coil and made the assumption it was good because I got spark. Now looking at it again it appears I need to revisit it because it says to replace the sensor. I will run through it again this weekend and let you know.
 

wryork25

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Serial number 0F765981 is manual 17 covering 305 and 350 1993-1997
Part number 8232251
Is this still available for download here in the forum, I saw some threads that said you posted it but I have yet to find it.
 
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