Installing a new TI board in the amp

[Lawrence S.]

I was on TI Specialty's site and noticed the upgraded circuit boards for the amp. I think my 69 L71 needs a new board. How difficult is this to install?

Thanks

Lawrence

[Mike M.]

Re: Installing a new TI board in the amp

very easy. mike

[Carl N.]

Re: Installing a new TI board in the amp

Takes longer to remove the module than to install the board.

[Richard M.]

Re: Installing a new TI board in the amp

Lawrence, Yes relatively easy.

I also recommend a new harness plug pigtail. I use the K&B module, as shown below. M&H makes one also. I get my K&B modules from Zip Corvette and sometimes from K&B directly from fellow member Ken Anderson. If I am not mistaken, Ken gives a lifetime warranty on his products.

Here are a few photos of the swap out process using the K&B Module.
(edit....sorry, I got a little carried away but I like doing this for those feeling electrically challenged. Don't be scared, it's easy, but a few precautions are described below to note)

I used several old file folders from different cars so the photos are of various pieces for several cars.

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Remove the module case from the car. Three 1/4-20 bolts/nuts/washers hold it there. This may vary based on year. This example is a 1967 model, left skirt in the headlight area. You must remove it from the open hood area if grille and bumpers are installed, so always use a prop bolt through the hood support pivot hole while your arms are in the nose hole between the hood and surround.


There is a Ground lug attached to the radiator support on this model. That can stay but best to remove, clean, and reinstall to ensure a good ground.


With the case on the bench, remove the 6 screws holding the rear cover. There will be a rubber seal between them.










The original Delco circuit board is wired to the pigtail at 3 terminals. Pry the terminals from the board. Mark the board with their colors for reference. Loosen the 3 screws holding the board to the case. Note the lower screw has no flat washer as it was the ground point with a toothed washer.






Carefully pry the board up a bit. There will be a small transistor appearing as still attached to the case. This is held in with a beryllium copper flat spring to act as a tensioner for the transistor heat sink position in the hole. Gently pry the transistor up and out of the hole using a small hook tool or pliers. Since I always save and sometimes repair the original boards I try to protect them.
















Lift the board out. Remove the copper piece and clean the hole of old silicone grease. Clean and refinish the case if desired.






If replacing the plug pigtail, remove the 2 screws holding it into the case and pry it out. Note the orientation of the plug with respect to it's singular facing terminal. This faces towards the module.



Here is the K&B circuit module. This is a older module from several years ago and the later versions may be slightly visually different.







Place the module int the case, circuit side up. Use the 3 screws to hold it in, but make sure you use additional toothed washers between the screw flat washers and the board. Tighten securely. The screws are important to ground the case to the board. If the screws tend to bottom out, cut some off or use shorter screws.


Attach the color coded wires to the board. Push the terminals down firmly but use caution not to break them. Note the Power connection(2nd photo) could be a Pink or a Brown wire in the Main TI harness based on year. The pigtail is always a Brown wire.






Check the 3 wire terminal clearances to the case cover. If it appears the terminals are too close to the cover, bend them slightly. You can add some insulation tape over the terminals if desired. It may be necessary to use a new cover rubber seal if the old one is deteriorated. It has also been discussed to add some silicone grease to the rubber lip to aid with internal moisture prevention.

Place the rubber seal on the case and install the cover using the 6 screws. Note the rear cover edge profiles can vary based on month/year of certain models.










Before returning the module to the car, clean any paint away from the module mount bolt boss which holds the MAIN TI Harness ground wire lug. This boss location can vary based on year. Ensure there is a clean bare metal area where it attaches with the 1/4-20 bolt. There is a integral ground lug which also attaches to the radiator support, screw assembly with toothed washer as shown again below. This Ground at the module is in the wrong location. After restoration, the Ground wire was located at the lower bolt below the rubber harness plug, for the 1967 application. This can be seen in the AIM UPC K66 Sheet A2.


One "non-typical" recommendation.... The C2 AIMs do NOT show a toothed lockwasher to be used at the grounded lug position of the module case where the mount bolt attaches it to the skirt. I use a toothed LW between the case boss, bolt and the Ground lug. This helps ensure a consistent ground. Different years may have varying ground lug locations. Your AIM will show it in the applicable K66 section.

Ground wire lugs shown(left side) on a 1967 TI Harness harness. Earlier and C3 similar. This Ground wire feeds the Ignition Coil- Negative terminal. Be cautious of earlier years(1964/1965) as the TI harness to Coil +/- color coding is different. It actually reverses the Black & White wiring to the coil. See your year AIM K66 for details.



Reinstall the completed module assembly to the car, noting the Ground information above, and reconnect the main TI harness to the module pigtail plug. Ensure this is a firm connection and that you have not pushed the pigtail female terminals into the plug. This has been a problem in some cases. It is recommended to add a little silicone grease to the inner rubber surface of the plug(not the terminals) to seal out moisture.



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[Joe R.]

Re: Installing a new TI board in the amp

Great job 'splainin' as always, Rich!!!

[Ken A.]

Re: Installing a new TI board in the amp

Rich, the original case was spotfaced on the front side where the mounting bolts go thru. This was done to ensure a good ground, which is critical to the TI system. The harness was grounded to the amp and to the radiator support.

[Richard M.]

Re: Installing a new TI board in the amp

Thanks Joe.

Ken, Yes I should have mentioned the importance of a clean ground at the bolt mount which attaches the ground wire. I'll edit my post to include that.

[Edward J.]

Re: Installing a new TI board in the amp

Larry, there is even a Newer design that K&B sells. the newer design is all enclosed and is a plug and play as the one Rich shows, and there's even a few tweak's installed on the new circuit board for quicker start's and can compensate for a weak magnet on the pole piece. I just put one on a friends 68 TI car. L.I. corvette sells the item 48-34b

[Lawrence S.]

Re: Installing a new TI board in the amp

Guys, thank you! That is super helpful. Will report back on my progress.

Lawrence

[Jim D.]

Re: Installing a new TI board in the amp

Larry, there is even a Newer design that K&B sells. the newer design is all enclosed and is a plug and play as the one Rich shows, and there's even a few tweak's installed on the new circuit board for quicker start's and can compensate for a weak magnet on the pole piece. I just put one on a friends 68 TI car. L.I. corvette sells the item 48-34b

I just installed one on my 65. It's a very nice product. Zip sells them for quite a bit less than LICS.

[Joe R.]

Re: Installing a new TI board in the amp

Just to help along. All vendors can supply the K&B amplifier. You can order it from your favorite vendor or on line.

JR

[Edward J.]

Re: Installing a new TI board in the amp

Rich, I think I may have mis-quoted on the module update, as Jim posted maybe it was made by M& H, not K&B,

[Jim D.]

Re: Installing a new TI board in the amp

I didn't pay attention to the pictures. The one I installed is from K&B like what Richard posted above.

[Richard M.]

Re: Installing a new TI board in the amp

The photo link to part# 48-34B on the LIC website has changed to reflect the K&B product. Before it showed both the M&H and K&B as the same part# on their link. I had that previous post deleted as it is now confusing since the LIC correction.

For reference, this is what the M&H product looks like. The 3 terminals have different wiring code connections based on other GM model/year applications.

For Corvette:
Term 1 Brown (Power)
Term 2 Gray (Distributor)
Term 3 Black (coil+) not Ground


Rich