Tappet adjustment

Post Reply
Dfisher32
New poster
Posts: 9
Joined: Sat Sep 24, 2022 11:21 am
Location: Louisville, KY

Tappet adjustment

Post by Dfisher32 »

I read in Chrysler's service manual to do a tappet adjustment when the engine is warm. Why? I've always made these adjustments on other engines when they are cold. I'm currently struggling to get one of my 318s to run, and it sounds like the valves could be out of adjustment, so I'd have to check clearances while the engine is cold. The first issue I had was no spark, which was mainly a grounding issue--replaced all ground straps. I also installed a hard start relay. I have replaced the battery with a 4D size battery--plenty of cranking amperage. I've also replaced the starter solenoid, ignition coil, distributor cap, and electronic replacement for points. When the engine turns over now it is slow and uneven, as if it is under a load. I'm thinking I should pull the plugs out next and turn the engine over to see if the valve adjustment has anything to do with this. Does this make any sense?
BlueSkye
Aluminum Star
Posts: 102
Joined: Sun Jul 20, 2014 9:38 am

Re: Tappet adjustment

Post by BlueSkye »

What kind of engine do you have? There is no valve adjustment on the 318. It's unclear if this engine is new to you.

Another grounding vulnerability is the connection of the starter to the block. I have had trouble once with the red wire connections being dirty.
1971 32ft Express 2x318
Seneca Lake, Erie Canal, Lake Ontario, Rideau
User avatar
tundrarules
Aluminum Star
Posts: 145
Joined: Fri Jul 11, 2014 11:17 pm

Re: Tappet adjustment

Post by tundrarules »

Did you check your cylinder pressures? Pressure gauge can tell you lots of info.
1985 29 Sedan
Edelbrock 1409 carbs
Mallory distributors
Pertronix Flame-Thrower coil & wires
780 hrs/eng
TN River, MM 213.8

:mrgreen:
Dfisher32
New poster
Posts: 9
Joined: Sat Sep 24, 2022 11:21 am
Location: Louisville, KY

Re: Tappet adjustment

Post by Dfisher32 »

I’m not new to this engine, but it has been several years since I’ve fooled with one. I have considered doing a compression test. I think I’m going to check distributor adjustment next.
Fastjeff
Site Admin
Posts: 1522
Joined: Sat Jul 12, 2014 5:06 am
Location: Rock Halll, MD

Re: Tappet adjustment

Post by Fastjeff »

Check the advancement set up in the distributor. They are notorious for sticking and messing up the timing of the engine.

No valve adjustment on 318s and 360s.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
Dfisher32
New poster
Posts: 9
Joined: Sat Sep 24, 2022 11:21 am
Location: Louisville, KY

Re: Tappet adjustment

Post by Dfisher32 »

Fastjeff—when you say “sticking” what usually causes that—age, lack of lubrication?
Fastjeff
Site Admin
Posts: 1522
Joined: Sat Jul 12, 2014 5:06 am
Location: Rock Halll, MD

Re: Tappet adjustment

Post by Fastjeff »

The advance mechanism under the plate (where the hall effect sensor is attached) tends to hang up and not return all the way at idle speeds. When that happens, and you time the motor, it ends up a bit retarded.

To avoid that, I "exercise" the mechanism by flipping it to full advance, then letting it snap back, several dozen times. That cures it for a while.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
Post Reply