HOW TO INSTALL A TACH METER IN A 1986 K10 CHEVY TRUCK WITH 6,2 LT ENGINE

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MARKOSPBSA

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I own a 1986 k10 6,2 liter diesel engine chevy truck that has no tachometer. Please, could anyone guide me how can i install a free market tachometer on the dashboard and what kind?. Thank you very much.
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Vbb199

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I believe it wires in on the injection pump, but that's a question for our neighborhood diesel guy @Blue Ox
 

Blue Ox

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Those pumps don't have any provision on the injection pump. Your easiest option is an alternator driven tachometer that uses an AC tap on the alternator.

GM used a signal generator on the vacuum pump/oil pump drive on GMT400s, but no idea how the tach read that signal.

If I ever get around to doing it myself I'll let you know what I figure out.
 

RetroC10Sport

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Big trucks could have a factory tach and diesel. I believe they get a signal off the alternator.
 

MARKOSPBSA

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Τhanks a lot for your replies. To get a signal from the alternator, from which point of the alternator should I get that signal? My alternators look as at the attached photos. Thank you.
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Rickf

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The tach that I put on my 6.2 NA had a pick-up that clamped to the housing. I don't recall where I bought it or what brand, ask mr. google.
 

MARKOSPBSA

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From which point at the housing? From the positive output terminal, from the Terminal 1, or from the Terminal 2?
 

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It's usually an AC tap from one of the phases before the "triode." You'd be best off consulting and alternator rebuilder to see if they can add a terminal for you.
 

MARKOSPBSA

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I' ll do that. Thanks a lot.
 

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If you can physically fit a CS130 or an AD230 (CS144, AD237/AD244 if an HD charge with a larger spacing for the ears, but i dont think yours has that from the looks of it) which are common retrofits onto small blocks, big blocks, and I imagine wouldnt be too hard on a diesel(Im unfamiliar with the amount of room, bracketry). If you can put one of those on, you will increase your alternator output a good amount with a very good upgrade to the features including a built in tachometer signal on the 4 pin plug, the only other wires relevant also being on the same plug(one is a sense wire like yours has I think?) and one is to a charge light or resistor for turning on like yours would also have.

Im not sure how those signals work or what all goes into it, but i Believe its similar to a HEI tach signal unless IM mistaken.

Just a thought if you would like to upgrade your amps too. The cs130/ad230 alts also have built in delays that soften the sudden load on the belt as well which could reduce any possible slipping with large demand or wear on the belts, since the old ones are more ON/OFF and that can shorten a life of a belt especially when its not dampened with a tensioner like a serpentine setup. if you wanted another benefit :)
 

Rickf

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Buy an autometer diesel tach part #3788, clamp the pickup to the housing, follow the instructions and you are good to go. KISS, there is no need to re-invent the wheel.
 

MARKOSPBSA

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I thank very much both of you for your replies and suggestions.
 

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Duh, just hook it to the tach signal portion of the distributor. Then when it sends spark to the plug you'll get a pulse. :chair:

Joking aside, I've never thought about this and Rick's advice seems to be the easiest.
 

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