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Replace Distributor Cap and Rotor Advice - 1986 720


Seaway

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1986 720

 

I will be replacing plugs, wires, cap, rotor, air filter, oil and finishing up replacing all the vacuum lines in an attempt to have a baseline so I can get the engine running a bit better. I am looking for a bit of advice regarding installing the new distributor cap and rotor.  I assume I can remove the cap, remove the rotor and then reinstall the new rotor in the same orientation as the old one was, correct? There is nothing that will need to be set as far as ignition timing is concerned?

 

 

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Just replace the wires one at a time, there's 8, and easily mixed up. Cap and rotor can only go on in one position so you can't go wrong with these. The rotor has a screw that holds it on. Plugs are NGK BPR6ES (qty.4) on the intake side and BPR5ES (qty 4) on the exhaust. Use only NGK.

 

Set the valve lash to 0.012" intake and exhaust with the engine hot.

 

At some time it's a good idea to re-torque the head gasket. The Z24 has a tendency to blow the head gasket every 100K. The preventative is to re-torque the head bolts once a year. The procedure is to do this on a COLD engine and loosen and tighten ONE BOLT AT AT TIME only. Any order you like.

 

The ignition timing can be checked with a timing lamp. Unlikely it has moved but if it has, the distributor can be loosened at the adjustment screw and turned.

 

Confirm that both coils are firing while cranking the engine over by placing an old spark plug in the coil wire and laying it on a grounded surface. If the one side is not working replace the first fuse on the left in the fuse box.

 

Today's oil has reduced levels of ZDDP, an anti scuff additive used on flat tappet cams like out old Datsuns. Today's engines are all roller rocker and don't need it. I don't believe what they say about the newer oild still protecting out cams so I use a light diesel oil that still has a high concentration of it. Either 15w40 Shell Rotella T or Chevron Dello 400. Do NOT use Fram filters. NAPA Gold or WIX are still good.

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Great, thanks very much.  I replaced the plugs the other day as the auto-lites that were in it were all gapped incorrectly, and none were the same.  The color didn't look too bad though.  I used the NGK plugs you suggested and the plug wires I got are also NGK.  I have had good luck with both in other applications as well.

 

I will see if I can borrow a timing light and check to see if the timing is okay.  

 

I am eager to work on this truck again after the I was out of town and then we had temps in the 20's for a few days.  Every time I drive it I like it a little more.

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So I have read. That was what was on it when I picked it up. The filter is new and the oil looks clean, but it is on the list if things to do. I am headed to my garage in a few to do the plug wires and the rest of it. I will update after.

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Installed new cap, rotor and wires. The old distributor cap and rotor were shot. Got everything back together and it still idles like crap. I did manage to drive it home from my garage the mile or so to my condo without stalling, so that is progress.

 

Idle is still lumpy. I sprayed carb cleaner on everything with no change. I have replaced all the vacuum lines per the diagrams I have found. It seems to start easier, but once warm the idle fluctuates from about 900-1200 rpms.

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