Thread: points to hei

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took that off jerry and still nothing.

he took the coil and disconnected it from everything. he then took the coil wire and put a spark plug in it. he put a wire to the - then another one to the + and put those wires to the - and + to the battery. he grounded the spark plug to the block. the wires sparked but the coil did not. I am taking the coil back to get my money but i really want to go back to hei.

Barb---you been jumping back and forth from the points to hei----do you know that the points plug gap is a lot less than the hei???if your gapped wide you might not get a spark--


ALSO----you are doing something very basic wrong---and from your replies I don't think you understand what we are trying to tell you--there are some very simple basic checks and if you think the coil is bad, why don't you try the original one???

i am gapped by the caddy book to coil specs. the old coil had a crack in it. that is why i replaced it. now i have another question. i have the hei distributo from my 350. the gear on the hei does not fit in my engine. can i change the top part of the hei by installing it into the points one. the lower unit is the same diamater.

Originally Posted by jyardgirl

i am gapped by the caddy book to coil specs. the old coil had a crack in it. that is why i replaced it. now i have another question. i have the hei distributo from my 350. the gear on the hei does not fit in my engine. can i change the top part of the hei by installing it into the points one. the lower unit is the same diamater.

The housings are different and I suspect the driveshaft is a different length. With enough time and patience, I suppose you could do it, but there is a better way. Call around to your local boneyards and find a HEI from a '75 or '76 500 CID motor. Same motor as yours, with a little longer stroke. Make a deal with the boneyard that the distributor is guaranteed to make fire or they will exchange it for another unit that will work or refund your money.

Begin with all spark plugs and the distributor removed from the motor. There seems to be some confusion as to what is #1 spark plug. I'm thinkin' that it is the front plug on the passenger side of the motor and that the firing order is 1-5-6-3-4-2-7-8 with the distributor rotor turning clockwise. 1-3-5-7 would be on the passenger side and 2-4-6-8 would be on the driver's side, just bass-ackwards from a Chevy. Is that what your service manual shows? We need to get this nailed down before going any further.

you are dead on tech with the firing order and odd on the passenger side. backwards from chevy. i will call around tomorrow to see if i can track down a distributor. the junk yards are closed here for the day. thanks tech.

Originally Posted by jyardgirl

you are dead on tech with the firing order and odd on the passenger side. backwards from chevy. i will call around tomorrow to see if i can track down a distributor. the junk yards are closed here for the day. thanks tech.

OK, put your order in at Summit for one of a Moroso 26140 HEI shim kit...
http://www.summitracing.com/parts/MOR-26140/
These are steel shims meant to be used at the bottom of the distributor between the gear and the housing to reduce shaft end play. They are not to be confused with nylon shims that are meant to be used where the distributor housing meets the intake manifold. Those nylon shims are used to restore the depth of the distributor gear into the cam gear following having material removed from the cylinder heads, block and/or intake manifold. Here is the blurb from Performance Distributors....
"The HEI does require some end play but nothing too excessive. We shim our distributors with 0.025" - 0.030" of end play. Any tighter than 0.025" can cause excessive gear wear and more than 0.030" can cause timing fluctuation."

Here's a piece I ran across on the net that shows the procedure for disassembly and assembly of an HEI. This guy sets the end play at 0.010". Performance Distributors says 0.025" to 0.030". I would listen to Performance Distributors, as they have done thousands of these. I would take your boneyard HEI apart according to your service manual and this tutorial and make sure it is a player before dropping it in the hole. Get some silicone oil to re-wet the felt that lubes the bushing.
http://www.rustpuppy.org/ignition2/Ignition%202b.htm
http://www.airsplat.com/Items/AC-TAG-SILICONE.htm

Crane makes an adjustable vacuum cannister and limiter plate that works well for dialing in the vacuum advance. The part number does not show working on a Caddy HEI, but I don't see how there could be that much difference in the upper end of the distributor.
http://www.summitracing.com/parts/CR...EVROLET&page=1

This will be a good time to verify the validity of your harmonic damper TDC mark on the inertia ring. The damper is made of 3 pieces, the inner hub which press-fits onto the end of the crankshaft snout, the black rubber-looking elastomeric material that allows the inertia ring to twist, and the inertia ring itself. Allowing for time and the harsh environment in which the damper must operate, the elastomeric material can break down, allowing the outer inertia ring to slip circumferentially in relation to the inner hub that presses onto the crank. If the inertia ring slips, you no longer have a reference to top dead center to ignition time the motor. Here is a company that will disassemble your damper and install new elastomeric material while clocking the inertia ring back to the hub properly.
http://www.damperdoctor.com/Merchant...egory_Code=CAD
And by the way, resist all temptation to purchase an aftermarket damper unless you need an SFI 18.1 damper to go class racing. The aftermarket damper units I have seen are bored incorrectly and are either too tight to press onto the crank snout or are too loose. The hub must be the correct press fit onto the crank in order to transfer vibrations (harmonics) to the inertia ring to be cancelled out. That's why they're called harmonic dampers. (They dampen harmonics if fitted correctly). When a piston fires, the force is transferred down the rod to the crankpin, which is offset from the centerline of the cylinder bore. This force twists the crank. The crank will only twist just so far until it meets resistance in the core of the crank. It then springs back the other way to its limit. Then back the other way, then back the other way. All of this bending back and forth happens very rapidly and can be likened to plucking a guitar string. If the back and forth harmonics are not cancelled with a damper unit or blower drive belt, they can crack the crankshaft. You know without a doubt that the OEM damper has the hub bored correctly or it would not be sitting on the end of the crank in the first place. It would have been scrapped at the factory. That's why I like to have Damper Doctor rebuild my stock, OEM damper. I know the hub is correct.

Now, if the inertia ring has slipped and you don't want to spend the money for a rebuilt damper right now, here's what I would do. Remove all the spark plugs. Turn the crank with a socket and bar on the damper retaining bolt in the end of the crank. Have a friend hold his/her thumb over the #1 spark plug hole while you turn the crank clockwise. When your friend begins to feel compression being built in the cylinder, have him/her shine a very strong flashlight into the cylinder through the spark plug hole and watch as you slowly bring the piston up to top dead center. This won't be scientific, but it will get you close enough to fire the motor. A mechanic's mirror may be helpful. It's about the size of a quarter and is on a telescoping stick, sold at Checker Auto. When you get the piston to what you think is top dead center, you can install the distributor with the rotor pointing in the direction shown in your service manual and re-install all the spark plugs (AC #44). Gap them to 0.042"-0.045" for the HEI. Some folks will recommend a wider gap, but try them at this first. We're not fine tuning right now, we're just getting the motor running. Using a bright color of paint and a toothpick, make a mark on the timing tab that is attached to the front cover and also on the inertia ring of the damper so that the two marks coincide to mark TDC.

Just for the benefit of those of you who have never done this, there are 720 degrees of crankshaft rotation to make a complete 4-stroke cycle. In other words, the crankshaft rotates two complete turns to fire all 8 spark plugs. If you are attempting to find TDC on the firing cycle, you will need to do the thumb over the spark plug hole trick to feel for compression if you don't have the valve cover off the motor. If you have the valve cover off, you can see when both valves are on their seats and the piston is coming to the top.

There is another time that the piston comes up to the top on the other cycle, but it is with the exhaust valve open (on the exhaust stroke). If you ignition-time the motor off this exhaust cycle, the motor will not run. Both valves must be closed and the motor must be on the compression/firing cycle with the piston coming up in the bore to make compression. I see this happen every day on one forum or another, where the OP has stabbed the distributor into place and has run the wiring with the piston at TDC on the exhaust stroke.

thanks tech. i ordered the summit shims and will go over thoroughly all the info you gave me. found a distributor for a 75 caddy at a local yard for $100.00 with a 60 day warranty. hubby going to pick it up saturday for me. thatnks again for all of your help with this.

Originally Posted by jyardgirl

thanks tech. i ordered the summit shims and will go over thoroughly all the info you gave me. found a distributor for a 75 caddy at a local yard for $100.00 with a 60 day warranty. hubby going to pick it up saturday for me. thatnks again for all of your help with this.

In the meantime, chase down the hot wire that used to power the coil. Run it back to the starter switch and remove it. Replace it with a 12/10 ga wire that connects to the start/run terminal of the switch and goes directly to the plus terminal on the HEI. If you have to run the wire from the fuse block because you cannot get to the switch, make REAAAAL sure that the wire from the switch to the fuse block is not a ballast wire (a resistance wire that will cut voltage to the HEI when the wire heats up). Eliminate all other ignition wiring that is in the car.

If you have to order an original Service Manual for the Monte Carlo in order to get this whole mess sorted out, then go for it. Faxon Auto Literature.

i have all that wiring in place as my old engine was hei.

Originally Posted by jyardgirl

i have all that wiring in place as my old engine was hei.

Oh yeah, it would have been HEI stock. Cool. It'll be that much less work then.

if it aint running in three weeks i`m coming up there .. i`m off two weeks for thanksgiving as well as christmas ..

Originally Posted by HOSS429

if it aint running in three weeks i`m coming up there .. i`m off two weeks for thanksgiving as well as christmas ..

Meet me at the Richmond airport and we'll share a rental car....

thanks you two. you can still come even if it is running and take her out and let her rip.

Barb, I just noticed that the Monte is a '71. That would have come originally with a points ignition. Just because you were running an HEI on the motor does not mean that there is not a resistor wire coming off the switch, unless you or someone before you removed the wire and ran a genuine 12 ga or 10 ga wire. Be careful here please and double check the wire from the switch. Thanks. I don't want to see this boneyard HEI lay down on you as a result of insufficient voltage.