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Need help identifying which engine / oil tube

Fun Times said:
That ICM is a thunderbolt five from Merc that started in I believe it was in 1994.5… the year mentioned, Merc also had a kit that when the 4 went bad you upgraded to the 5 so anything is possible when using a ignition control module as a reference guide in situations like this….< plus, I could be wrong but the mounting hardware sort of looks different than what memory is trying to say in the moment.

An example,
www.ebay.com

Mercruiser 840130A4 THUNDERBOLT V Module 500 | eBay

840130 Thunderbolt V ignition module with knock module. No longer available from Mercruiser. I have two sets of these, this auction is for one set however.
www.ebay.com

To help maybe fine tune a search of the engine, if the numbers are available as mentioned/shown in either of the following guides, then it may help find a clue too…,
EN_08.PDF , mcsb02_08
Click to expand...
I have not seen that style TB module in use. Most from mid '90's were piggy backed on Dist. When a knoc module was used.
 
kghost said:
It looks like a inline 4 cylinder control module. Possibly a newer module used with a non efi engine.

But it ia NOT a Mercruiser Thunderbolt timing control module.

I will say, someone knew what they were doing, be it 100% not what should have been done. But they were smart enough to make it work.

In the pleasure boat world and especially when using a site like this to help with problems, Most if not all of us work with 99% OEM issues and what should be and how they work.

As seen we post links to the way the factory built it and use the SAME parts as listed to fix it.

You have a real bastard child...
Click to expand...
That is a TBV module for sure
kghost said:
Although I dont know 100% ,
I think, these ignition timing modules dont know or care if its a 4 cyl, 6 cyl or 8 cyl engine. Its the rpm and trigger (sensor and rotor assembly under dist cap) that pulse the timing module. The only other function of the module is the timing advance max amount and the rate at which it gets there.

Its common for boaters to use V6 TB modules for advance curve changes for V8 engines....(performance seekers)
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yes you can run a V6 module on a V8 , I did it on a test stand waiting on the correct module. At idle low rpm it ran fine, wasn’t sure if the rev limiter would get messed up with essentially having a different scale on the tach
 
kghost said:
I have not seen that style TB module in use. Most from mid '90's were piggy backed on Dist. When a knoc module was used.
Click to expand...
I think early 2000 s they went to this style module and mounted on elbow. This is exactly how my 2003 manufacture date engine is set up. Some have knock modules and some do not, depends on the engine. The base 2 bbl 4.3 and 5.0 did not use a knock module. Almost every 5.7 I have seen uses a knock module.
 
Dieter said:
I think early 2000 s they went to this style module and mounted on elbow. This is exactly how my 2003 manufacture date engine is set up. Some have knock modules and some do not, depends on the engine. The base 2 bbl 4.3 and 5.0 did not use a knock module. Almost every 5.7 I have seen uses a knock module.
Click to expand...
That may explain the non Merc part number on his. Merc simply went to a off the shelf Denso unit with programming for Merc Marine. They source them very low cost but sell at Mercs prices...lol
 
I think early 2000 s they went to this style module and mounted on elbow.
Click to expand...
Going of fading memory, I want to say they went from the distributor to elbow on probably either June or July 1 of 1995 as that was supposed to be generally when the next model year was supposed to come out/start.

The following is of the introduction of the five,
www.crowleymarine.com

THUNDERBOLT V IGNITION SYSTEM | Service Bulletin | Crowley Marine

15-MAY-1997 - Manufacturer Service Bulletin: THUNDERBOLT V IGNITION SYSTEM
www.crowleymarine.com www.crowleymarine.com

Then the parts breakdown with the mounting style mentioned,​

Find MerCruiser 5.7L GM 350 V-8 1988-1995 Engine & Stern Drive​

MerCruiser 5.7L (2 Barrel.) GM 350 V-8 1996 Wiring Harness & Electrical​

 
For myself, virtually all the boats I work on these days, about 15-20 annually are all pre 1995, most in the '80's. Lots and lots of 1980''s to mid 1990's in my area and most marine businesses wont work on the older stuff.
A few good fresh water lakes which are small as compaired to many. But because of this the older boats are affordable and easily repairable.
Mine is a 1987 Cobalt that I have had since 1995. Never seen salt water...it has the original style TB IV on the elbow. The large aluminum bodied one advance of 22*
 
Fun Times said:
Going of fading memory, I want to say they went from the distributor to elbow on probably either June or July 1 of 1995 as that was supposed to be generally when the next model year was supposed to come out/start.

The following is of the introduction of the five,
www.crowleymarine.com

THUNDERBOLT V IGNITION SYSTEM | Service Bulletin | Crowley Marine

15-MAY-1997 - Manufacturer Service Bulletin: THUNDERBOLT V IGNITION SYSTEM
www.crowleymarine.com www.crowleymarine.com

Then the parts breakdown with the mounting style mentioned,​

Find MerCruiser 5.7L GM 350 V-8 1988-1995 Engine & Stern Drive​

MerCruiser 5.7L (2 Barrel.) GM 350 V-8 1996 Wiring Harness & Electrical​

Click to expand...
Oh my, my apologies to everyone, I just noticed I made a mistake in my findings of timeframe above because in continues searching, the mounting hardware to the elbow was a bit later than my original thoughts. 😳

Parts for MerCruiser 5.7L (2 Barrel.) GM 350 V-8 1998-2001 Wiring Harness & Electrical Components​


Item 34 is of the different mounting design, https://www.marineengine.com/parts/...9999/wiring-harness-and-electrical-components
 
Fun Times said:
Oh my, my apologies to everyone, I just noticed I made a mistake in my findings of timeframe above because in continues searching, the mounting hardware to the elbow was a bit later than my original thoughts. 😳

Parts for MerCruiser 5.7L (2 Barrel.) GM 350 V-8 1998-2001 Wiring Harness & Electrical Components​


Item 34 is of the different mounting design, https://www.marineengine.com/parts/...9999/wiring-harness-and-electrical-components
Click to expand...
Thanks, That makes more sense as I worked in the business til 1996
Then went back to regular industry/corp job and did the boat work on the side. I wasnt seeing those in that time frame.

This further makes his current motor more of a bastard child. Late 70's to early 80's block, 87-95 heads and a 98-01 ignition....intake and carb most likely also 87-95 or at least intake.
 
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