help. Installed MSD distributor now oil light is on and loud knock

Here is a great link on what to look for when using a vacume guage

http://www.secondchancegarage.com/public/186.cfm

 

OK, here's an update.

I tested the vacuum on the car and it was pulling a steady 18" at idle. Needle did not show any signs of bouncing at all.

I checked for any vacuum leaks by spraying carburetor cleaner around the carb, intake manifold, brake booster and all the hose connections and the idle did not change one bit. My conclusion is that there is no leak anywhere.

I reset the idle and set the timing again to 10* and I'm using both blue springs for the centrifugal advance. I also put the black stop bushing back in there as well because the blue bushing gave me pinging at full throttle.

On to the puff puff sound from the exhaust. I examined all the spark plugs and all were carbon fouled. I was using the AC 44S plug and they still fouled and that's what was the cause of the exhaust noise. It also was sending unburnt gas out the tail pipes because of the black smoke at idle. I went ahead and replaced them with the Bosch platinums and the noise and smoke is now gone and the car runs noticeably smoother.

I also played around with the carburetor idle screws and have them about two turns out from stop. Is that too much?

Any help or suggestions is appreciated.

 

you'll want to turn the idle mixture screws evenly to where you get the highest idle speed which incidentally will be the highest vacuum. Then set your idle speed with the idle speed adjustment.

 

Thankyou very much for that bit of advice and it works. I just adjusted the idle screws til I could stall the engine by putting my hand over the air inlet on the cleaner.

Thanks. :TU:

 

That 10* of vacuum advance is in distributor degrees. In actuality engine degrees are 20. On an otherwise good product MSD has left the adjustability , totally, out of the vacuum advance. 52* of total timing cruising is TO MUCH!!!. This total consists of initial, mechanical & vacuum advances. You need to make a small metal piece to limit the total amount of vacuum advance to 10*-12*. This piece of metal will push against the vacuum advance arm/rod to limit it's backwards movement. Tony (Yacster) has just done this with my guidance. Ask & I'm sure he can provide a pic.

 

Jim- Tom and I just did that this weekend. His little sheetmetal "shim" worked perfect. It is a pain in the ass to do with the Distributor in the car, so I would take the distributo out. What we did is cut a piece of thin sheet metal about 1" long by 1/2" wide. At 1 end we put a 3/16" hole for the screw at the other end we made a "V" about 3/8 deep. Take the alan screw out of the vacuum advance arm just behind the advance rod that moves foward. Pull that little rod foward with some needle nose pliers and slide the shim in to keep the rod a little foward thus reducing your initial timing by 7-10*. Replace the screw through the 3/16" home to secure and you're done.:TU:
Tip- If you do it in the car- Remove the rotor it will make it sooooo much easier ou:

 

Thanks for the tip. I'll definitely work on it but instead of having to go into the distributor, wouldn't it be a lot easier to put a restrictor in the hose that goes to the canister limiting the amount of vacuum it gets?

For the time being, I've been playing with the advance curve some more and the engine seems to like the light silver springs the best with the distributor set at 9* of initial. I get no pinging at all and the car feels strong. This is running 93 octane gas with no booster additives.

So the black bushing limiting it to 18* plus my initial setting of 9* is giving me 27* total advance. The springs I have in it now bring in the total advance around 1700 rpms.

Is that giving me the total advance too quick? The car feels strong and no pinging is present so I'm thinking of leaving it as is. What should I do?

Thanks for any advice.

 

Read my timing specs in post above. You want 32* total mechanical, no vacuum. Since you only have 9* with the bushing in distributor degrees, 18* at engine, for a total of 32* you will need 14* initial, give or take. 1700RPM's is really too soon. It should be closer to 22-2500RPM's.

 

Go with what Tom and Yaccy are saying. Also my 2 cents worth. ck out the timing mark on the harmonic balancer to make sure it is at ''true'' top dead center.....I have seen them be off as much as a qtr. inch......

 

It is. I know just by having to hand turn the crank and getting the mark to line up on the 12 when I installed the distributor.

It all lined up just like the manual showed. The rotor was pointing to #1, both valves were closed and the mark was directly on the 12.

I still want to know about putting a vacuum restrictor in the hose instead of having to go back into the distributor. Won't that accomplish the same thing as what was described in the other post?

 

Sorry, but in one word NO!!!! Restricting the amount of vacuum will have NO effect on total vacuum other than it will come in later, even 52* later is TOO MUCH!!!!!

 

Jim, pard, the only way to determine actual top dead center is to make a stop that will stop the crank before it reaches tdc. I use an old spark plug that has a rod welded into the center of it..... i install the stop device and then by hand rotate the engine untill it comes against the stop.... then i rotate the other way by hand untill it comes up against the stop again.... then measure between the two points and divide by 2. That is the actual tdc. Mark actual tdc.
I have seen them be off by as much as a quarter inch on a new harmonic balancer..... naturally there is always the ones that the ring has come unvulcanized....

 

I set up my 425 using a 2 4 bbl distributor at the recommended 12 degrees advanced, NO vacuum. total came in around 34-35, ran great. Then I tried bringing in the advance sooner, pinged awful:error: . Went back to stock springsp .
I will be going to the same MSD in the near future, so this is all good stuff.
My Question:
I keep reading about using a 455 Harmonic balancer, "with modifications" what exactly needs to be done?
Thanks
Roger

 

The balancer has a slot cut into it. No ring to speak of.

 

OK, tomorrow I'm going to do the vacuum advance trick and then put the blue and silver springs in and time it up to about 14* initial.

You all are right. There's too much vacuum advance at full throttle and it's causing it to ping.

I want to know if keeping the vacuum advance arm from going back to it's original stop will necessitate me having to take it out of the mechanical. I intend to do it in the car so how far off will my initial be from the 9* I have it set to now?

Thanks.

 

Well.... he he.... that part that the slot is cut into is the ring.... the ring is vulcanized to the hub. Some times the ring will come unvulcanized from the hub and then the ring will rotate from actual tdc and the mark then is useless for timing the engine. but..... I had one that the factory had mis marked and the timing mark was a qtr. in. off from actual tdc.......

 

Been following along and I'm confused. If you're running the vacuum advance on manifold vacuum, it will not contribute to total advance at wide-open-throttle (WOT).

At WOT, manifold vacuum is near zero and the vac advance canister is relaxed. If this is really how you're running it, at WOT the only contributors are initial advance + mechanical advance = total advance.

If you're running the vac advance on ported vacuum, that's a whole different story, and it may indeed be one more contributor to total advance.

Devon

 

It's in the transition from cruise to WOT that the pinging occurs. I've tried to time it out with the springs and initial and it's not working. At cruise it runs fine but once I lay on the throttle, the marbles in a can sound starts to happen.

I got the initial set at a low 9* and I'm using the 18* stop bushing and still getting pinging at WOT. It's getting way too much vacuum advance.