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oil pressure and more
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Author:  jibs1723 [ Tue Mar 11, 2008 8:30 am ]
Post subject:  oil pressure and more

I have a 225 slant in a 64' valiant. Whenever i come up to a stop and am a little hard on the brakes, the oil pressure light will come on for a few seconds. The car is not low on oil either. Is this just the design of the oil pump and pan or is it more serious. Also when i am passing someone in second gear around 4200 rpm it starts to sound like its detonating. It only does it in second and is this because of the increased load? As soon as it shifts it stops. Any ideas would be appreciated
Thanks

Author:  Aggressive Ted [ Tue Mar 11, 2008 9:45 am ]
Post subject: 

I have had both symptoms on old SL6's over the years, but not with my new engine.

First off, you should be running a full 5 quarts of oil. However, at low rpms from a nearly stalled engine it is possible to slow the oil pump enough to reduce pressure. Especially on a worn engine with 10-30 weight oil, the pressure can drop to about 5 pounds or less.

The detonation at high rpms is from too much timing. On a distributor with a 15R governor (long slots) the springs may not limit the weights enough to keep it from continuing to advance at rpms over 4000.

Some options are:
You can use a stiffer secondary spring, rotate the secondary pin for shorter (less) movement, or get a governor with a shorter slot, or unplug the vacuum can and plug the line when you want to wind it up that high.

Author:  DusterIdiot [ Tue Mar 11, 2008 10:24 am ]
Post subject:  Yipes...

Quote:
1964 Plymouth Valiant 4 door V200
Quote:
The detonation at high rpms is from too much timing. On a distributor with a 15R governor (long slots) the springs may not limit the weights enough to keep it from continuing to advance at rpms over 4000.
I would ask first, are you running the stock distributor for your car... if so, then you've got the old points distributor with whatever governor they offered that year... In the mean time, you needs some diagnostic tools... a hand vacc. pump, and a vacc. gauge and a dial back timing light...

If it's pinging up high like that, you'll need to determine where the distributor is set (when you get the #1 piston to TDC, is the distributor at TDC or is it set to something else... it can be bad if someone just threw in the distributor at 10BTDC and called it good)... second using the timing light and vacc. hand pump you'll need to determine where the vacc. pod comes in at, and take a test drive using the same parameters(4200, second gear... with vacc. gauge hooked up, to see what your engine is doing... possibility exists that the vacc. advance is still 'in' while you are passing giving you that extra timing you don't need...)

After getting that information, come back and we'll get you the next set of things to adjust...

-D.Idiot

Author:  SlantSixDan [ Tue Mar 11, 2008 1:38 pm ]
Post subject:  Re: oil pressure and more

Quote:
I have a 225 slant in a 64' valiant. Whenever i come up to a stop and am a little hard on the brakes, the oil pressure light will come on for a few seconds.
Check the location of your oil pressure sender. On some '63-'64 engines, it is screwed into a boss in the rear of the engine block's oil gallery. This location can tend to lose oil pressure under hard deceleration; a 1964 TSB advised moving the sender back to its pre-'63, post-'64 location (screwed directly into the rear of oil pump itself, below the filter mounting pad) to eliminate the red-light complaint. Sometimes the senders themselves, regardless of location, are a little touchy and tend to "cry wolf" when there's not actually a problem.
Quote:
when i am passing someone in second gear around 4200 rpm it starts to sound like its detonating. It only does it in second and is this because of the increased load?
Others have already answered this one well: too much spark advance at high RPM.

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