Slant Six dies .... I should know this.....

[DianneB]

I have a '66 Lone Star with a Chrysler slant six that normally runs pretty well but every once in awhile when it has been running low RPM for awhile (like 1500 to 1800) it wants to die, particularly when I try to change the throttle setting. If it dies, it does NOT want to restart! (It did that to me today when I was trying to follow a friend's houseboat - bugger quit on me in the middle of ROUGH open water - GRRRR!)

My Dad was a mechanic and I should know the likely causes for this ... water in the gas? .... plugs, point, & condenser? ... needs a carb overhaul?

Any other old-timer engine people remember the most common causes of intermittent 'wanting to die' ?

 

[a70eliminator]

Re: Slant Six dies .... I should know this.....

Sounds like one or more plugs loaded up and fouled out, once that happens it's pretty tough to restart, then when it does restart you have to rev up to clear all the unburnt fuel out, complete tune up and carburetor rebuild.

 

[Bondo]

Re: Slant Six dies .... I should know this.....

Ayuh,... Atleast a complete Tune-up,+ Fuel Filters...

 

[DianneB]

Re: Slant Six dies .... I should know this.....

Thanks.

I have done all the fuel filters so I guess it is tune-up and carb rebuild next.

 

[Baysidejoe]

Re: Slant Six dies .... I should know this.....

The slant six was noted for eating up points and condensers. I had two slant six vehicle in my younger days and had to do this change about every six months. Motor will last forever.

 

[EddiePetty]

Re: Slant Six dies .... I should know this.....

....slant sixes never die!!!! They might hibernate for a while but never really die.
As previously mentioned, they were (and still are) rough on ignition parts, especially if they had the Chrysler cermanic in-line resistor. The resistor would either fail to 'open', or worse yet, the winding would rupture and re-weld itself to a lesser resistance location.
In addition to your fuel checkups, be sure to go through the distributor components and check your resistance voltage to the coil.
Speaking from the automotive side, over the years (last century!!) I must have replaced hundreds of slant six fuel pumps. They would rupture the diaphragm and puke fuel into the sump. In your application, the leaking fuel should be sent to the carb via a translucent tube ending at the carb's airhorn (may not have been USCG required in your year).

 

[Don S]

Re: Slant Six dies .... I should know this.....

....slant sixes never die!!!!

Hate to be the one to say this, but mine did. Took a trip from California to Ohio for Christmas one year, the old Dodge van went all the way there and back (seen -21?F on the trip) to within 100 miles of home and it threw a rod out the side of the block and pan. It obviously hated the trip to cold weather.

In your application, the leaking fuel should be sent to the carb via a translucent tube ending at the carb's airhorn (may not have been USCG required in your year).

In 66, that type fuel pump wasn't even invented. Fuel would go into the oil pan or in the bilge. Even the Chevy points distributors with the little window to adjust the dwell was used back then. It was the early to mid 70's that safety started showing up.

 

[NHGuy]

Re: Slant Six dies .... I should know this.....

If you suspect the fouled plug scenario you can do two things to verify.
One: do the 1500 rpms til you expect the problem. Then cause the problem intentionally. Put out your anchor & pull the spark plugs for a look. By the time you put em back in the engine will probably start. Plugs are cheap enough that you might as well bring some along all gapped & ready.

Two: do the 1500 rpms again til you get the problem. Then when you go to restart do so with a wide open throttle and a hand on the lever so you can keep the revs under control. Carburetor engines can be fed a lot of air this way and will sometimes restart and can be run until cleared.

I'd just do the points, condenser, cap, rotor, timing & wires if they aren't fresh. I bought the boat in my signature two years ago from a "mechanic" who said he did all the maintenance. I redid the cap & rotor year one. It wasn't satisfactory. Since it has no points I didn't do them. In year 2 I did the cap, rotor, plugs. No change. When I did the wires it was like I had turned a switch, what a difference. After that I checked the timing and found it 2 degrees retarded, so I set it up. The old wires on the boat looked good til I removed them, then they looked tired.
Coils don't go out very often, there are procedures to check them. But I wouldn't check the coil or timing advance til you do the "regular" ignition stuff first.

I'm not arguing with the carb rehab, it may be needed, but ignition is a more likely culprit and a better first place to look.