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 Cdi engines  
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Post Cdi engines
What's the difference between a cdi engine and a non cdi engine, and how do you tell?


Thu Feb 28, 2013 1:38 pm
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Post Re: Cdi engines
The charging system.

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Thu Feb 28, 2013 1:39 pm
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Post Re: Cdi engines
So the non cdi engines don't have a charging system?


Thu Feb 28, 2013 1:42 pm
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Post Re: Cdi engines
Visually on a CDI theres a sticker on the front that will say Marine. They have a larger rectifier and the fuel pump is mounted on the valve cover (vacuum), No ID tag riveted to the block, stainless exhaust.


Thu Feb 28, 2013 1:46 pm
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Thu Feb 28, 2013 1:49 pm
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Post Re: Cdi engines
A non cdi doesn't charge under 2500 Rpms either

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Thu Feb 28, 2013 1:52 pm
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Thu Feb 28, 2013 2:20 pm
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Post Re: Cdi engines
Whats the cost to convert the motors from non-CDI to CDI? Coils ect ect.


Thu Feb 28, 2013 3:01 pm
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Thu Feb 28, 2013 3:07 pm
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Thu Feb 28, 2013 4:49 pm
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Thu Feb 28, 2013 6:02 pm
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Post Re: Cdi engines
SO I need the charging box by the starter and the coils....thats all???

I'm confused.


Thu Feb 28, 2013 6:04 pm
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Post Re: Cdi engines
ive heard that this can be done by more then one person but
never get a straight answer on what all parts are needed and how much it would cost

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Thu Feb 28, 2013 6:34 pm
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Thu Feb 28, 2013 6:48 pm
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Thu Feb 28, 2013 6:50 pm
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Thu Feb 28, 2013 7:41 pm
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Post Re: Cdi engines
The old blocks don't have the bolt pattern to add the new rectifier. Since your all mighty know it what parts do you need than please share with me. Also, I wasnt telling him the parts cause they would work I was simply stating what would be needed of so

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Thu Feb 28, 2013 7:55 pm
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Post Re: Cdi engines
now im confused

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Thu Feb 28, 2013 7:57 pm
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Thu Feb 28, 2013 8:09 pm
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Post Re: Cdi engines
i think their were more then just the 2 of us wondering but thanks

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Thu Feb 28, 2013 8:14 pm
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Post Re: Cdi engines
The thread is kinda mixing up the standard features of different motor types. The different options that come standard in that motor type dictate the specific parts dependencies. The coil type triggers a string of dependencies depending on where you start from. First I will go over the motor types and standard features.

The horizontal motor type that has been out for years:
613477-0121 - It has stock coils w/o rev limit, cam operated fuel pump (in the valley of the motor between the heads), 20A stator and voltage regulator, standard wire harness (to match the stock coils- there are diodes on the harness on the ground wire for the coils and the 20A voltage regulator output goes through the key switch). The 20A stator is smaller and mounts to posts cast into the block under the flywheel. This type has a steel stock muffler and purple governor spring. I have seen newer model motors with stock coils but with vacuum fuel pumps too- not sure if this is a standard change or not.

The 'Marine Edition' motor:
613477-0194 - Has potted sealed CDI coils w/ 4300 RPM rev limit built into the coils, wire harness for those coils (no diodes at the coil ground wire) and Deutsch waterproof main electrical connector on the wiring harness, Stainless Steel Stock muffler. Since it has CDI coils, it has a flywheel with keyway cut in the position for those coils. The flywheel is embossed, about 5# lighter, and accomodates a 50A stator which is standard on this motor type. The 50A stator requires a matching 50A voltage regulator, the 50A voltage regulator output connects directly to the starter post rather than going through the key switch. The 50A stator is larger and mounts to different holes in the block, the block is modified slightly where the mounting posts for the 20A stator are cut down. As posted, the newer blocks are tapped for both stator mounting patterns. This motor type also comes standard with a vacuum operated higher volume fuel pump mounted on the valve cover which requires a different intake manifold where there is a fitting installed to operate the fuel pump. Finally it comes with a stainless steel stock style muffler and a longer reach Brown governor spring - all other parts are the same.



The High Rev Marine Edition
613477-0218 - same as the -0194 but the CDI coils have a built in 4700 rev limit with different valve springs (they have a different part number but may just have shims installed on the stock springs) and governor spring which accomodates the higher rev limit.

The coil type requires the flywheel key slot cut in different positions relative to the flyweel magnet- There are different flywheels for the stock coils and the CDI coils.

Flywheel key position comparison- CDI is on the left:


There are different flywheels to accomodate the different stator types - 20A and 50A. The flywheel for the 50A stator is embossed and lighter than the flywheel normally installed on the type -0121. Years ago there was a 50A conversion kit that BoatDr had which had a flywheel with the key slot cut in the position for the stock coils but accomodated the 50A stator. Not sure if they make this conversion kit any more. If you have a 50A stator you also need a 50A voltage regulator.

Inside of the flywheel -50A stator is on the left:


The mounting positions on the block are different for the different stators- the holes marked in blue are for the 50A stator. This block has the 20A mounting posts cut down (marked green) but the block is tapped for the bolts.


50A stator:


To convert from Stock coils to CDI coils you would need to have a flywheel with the keyway cut at the position required for the CDI coils, then modify the wire harness. The CDI coils have the diode included in the circuitry inside the coil. If the wire harness coil ground wires have diodes on them, the diodes would need to be cut out and a pig tail with female connector installed to connect to the CDI coil ground tab. The flywheel from Briggs that has the keyway cut for the CDI coils is intended for the 50A stator (this is where the string of dependencies starts). So to use this flywheel and have a charging system, you would also have to convert to the 50A stator. If you convert to a 50A stator, you also need the 50A voltage regulator. Depending on the age of your block, it may already have the holes tapped for the 50A stator mounting position (newer blocks already have both sets of holes as posted above), if not the block would need to be tapped and then the mounting posts for the 20A stator would need to be cut down~ 1/2". I have run CDI and Stock coils on the same blocks and have done this. Since there are so many dependencies (and $$) involved in this string of dependencies, it would be more cost effective to have the stock coil flywheel broached (new key slot added at the position required for the CDI coils) so you can keep your 20A stator etc.... I have not done this (yet) but one thing to consider is the embossed flywheel that comes on the CDI coils is lighter than the stock flywheel, but this may only be because of the 50A stator has such stronger magnets giving more resistance at start up. There is also an embossed lighter flywheel for the 20A stator as well (I have one). Note- I am not sure if the cam operated fuel pump gives the volume required for the CDI coils with electronic timing advance. If not, then either install an e-fuel pump or add the vacuum fuel pump which requires the intake manifold to be modified (nipple added). If the CDI coils installed are High Rev (4700 rev limit) you would also need to add shims to your valve springs and it would be a good idea to change out the governor spring to either the silver one for the -0218 or brown one with longer reach for the -194.

To add Stock Coils to a motor with CDI coils and 50A charging system, you would need the diodes added to the coil ground wires. Easiest way to do this is cut the end of the wires with diodes off a wire harness intended for stock coils, cut the female connector off the ground wires to the CDI coils and splice the diodes in. You will also need a flywheel with the key position cut for the Stock Coils. You could have a new key way broached into your existing flywheel or go through the string of dependencies to convert to a 20A stator. If replacing the flywheel with one for a 20A stator, you can add some 1/2" spacers on the mounting bolts behind the 20A stator to put the stator in the right position. After adding the 20A stator you also have to change out the voltage regulator. When I did this, I just cut the red wire at the 20A voltage regulator connector (leaving the two yellow wires that connect to the stator) and spliced on a wire with a ring connector on the end to mount directly to the starter post. That way I didn't have to mess with the rest of the wire harness.

Hope this explains it, I probably missed something but its involved either way you go.

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Fri Mar 01, 2013 6:34 am
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Post Re: Cdi engines
After the costs of the flywheel, stator, coils, box and your time a person is probably better off buying a new crate CDI stock motor when its all said and done and switching performance parts to it lol


Fri Mar 01, 2013 8:42 am
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Fri Mar 01, 2013 8:10 pm
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Fri Mar 01, 2013 8:14 pm
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Post Re: Cdi engines
Really? Not the motor pic because i have diodes off my coils. The non-CDI flywheel or something?


Fri Mar 01, 2013 8:25 pm
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Post Re: Cdi engines
Are the CDI engines slower / less hp than the non if so how much slower

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Fri Mar 01, 2013 8:49 pm
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Sat Mar 02, 2013 2:30 am
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Sat Mar 02, 2013 8:18 am
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Post Re: Cdi engines
X2...


Sat Mar 02, 2013 9:34 am
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Sat Mar 02, 2013 10:48 am
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Sun Mar 03, 2013 7:31 am
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Thu Mar 14, 2013 8:00 pm
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Thu Mar 14, 2013 8:55 pm
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Post Re: Cdi engines
Gary ~ I'ma 'bout to correct you ...... these ain't "Motors" .... thay are "Engines" .... :lol:

'Preciate yore input as always. Thanks fo bein' around.

Do ya'lls find the new CDI's bein' alot more cold nature than the old style ?

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Fri Mar 15, 2013 9:48 am
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Post Re: Cdi engines
Everyone I seen that didn't idle was due to leaking valves...after either heads or at least a valve job they idled good...


Fri Mar 15, 2013 10:21 am
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Post Re: Cdi engines
Gary I see the coat hanger and the flywheels, you been talkin to Cody? We done mine like that last year.

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Fri Mar 15, 2013 2:44 pm
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Post Re: Cdi engines
i have a cdi motor with the 4300 coils all i have to do is buy the 4700 coils and i will be good no other mods to turn that rpms???


Mon Apr 08, 2013 6:55 pm
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Post Re: Cdi engines
If you have a stock motor these will not give you any gains. You will need to mod motor to take advantage of the RPM range increase.

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