56 Buick

Excellent, thank you.

Thanks to you both. I will ditch the grease and go with the permatex.

Thanks John. Mating surfaces were clean. I can try the permatex. Was it the permatex blue or permatex ultra blue?

Hi all I recently replaced the water pump on the 56 Buick and also replaced all gaskets on the water manifold crossover. The issue is that bottom rubber seal between the crossover and the timing cover continues to weep. I can see coolant collecting on top of the timing cover. I have had 2 goes at pulling the crossover off again and attempting to stop the weep. What am I doing wrong? The only thing I can think is I have been putting rubber grease on the seal to assist with the crossover fitting into the timing cover and instead I should leave the rubber seal naked. Could I try adding the GM coolant system seal tablets? If anyone has some helpful ideas that would be much appreciated. Thanks Drew

Just asking: is it the mesh hood vent that was used in the early cars? I recall someone saying the hood vent was changed to solid fill to avoid rain and kicked up water on the road passing thtough the hood vent into the engine bay/oil bath air filter?

Thanks. I had heard it is often the fuel boiling away down near the mechanical fuel pump but I will give it a try and see if it starts.

Thanks, will try this.

So how do you get the car to start in this circumstance? After the car has been driven and the engine will not start again, I have always had to wait until the engine cools down after which it then will. But I have only ever assumed it was vapour lock and not tried much else.

Thanks. I will connect a vacuum pump and see if the distributor plates moves. Is the plate supposed to move and hold at the advanced position or will it rather be momentarily?

Hi all, I hear you re possible issues with the fuel delivery system and I will check as suggested. I have never continued to crank the engine for 30 seconds or more as I have been concerned with the battery and straining the starting circuit but I can also try and see. However, another reason for the priming pump was to counter the vapour lock that can occur. The car can be difficult to start again while hot after a drive. Gary's link above to his work and write up is really great and informative. Thanks to all.

Hi, I am looking at fitting a low pressure fuel pump to prime the fuel bowls. Unfortunately when the car has sat for over a week, it is impossible to start the engine. It appears the fuel evaporates and the mechanical pump just can't move the fuel. I am still going to use the mechanical pump to run the engine after it starts so this electric pump will just run for a few seconds to prime the carb. The electric pump will need to be a pump where the mechanical pump can pull fuel through even when the electric pump is not running. Also, it will only need to be a low 2-3 psi pump, that way no regulator should be needed. I am interested to see if anyone has dome something similar? If so then what parts did you use and were there any issues encountered? Thanks Drew

I am certainly carrying a spare now. I did end up removing the carbon rod from the distributor rotor given its resistance was extreme and replaced it with a length of aluminium rod that I set in place with a small amount of epoxy.

Hi all, just an update. Turns out it was the coil. Using a replacement the car runs fine. It was correct that despite the coil measuring to spec, the coil was faulty and not providing regular/strong spark. Thanks to all for your assistance.

True but I recall that when I removed the crash pad on my car, I did require a 2nd person to assist in getting the crash pad away. It required some flexing and manipulation by someone as the other pulled. But certainly does make things easier to work on.

Yes, that is the ballast resistor in the primary ignition circuit. I have never noticed it to be hot though. As you suggest it may be due to the battery charging but I have no idea why that would occur. Perhaps others will have a more informed view than me.

Also I think you are saying the glass bottle is a reservoir but it is not really, albeit it does hold the washer fluid. A vacuum line will feed a small vacuum operated pump inside the bottle. That pump pumping washer fluid to the washer jets to spray washer fluid on the windscreen.

Just my 2 cents but I would proceed to see what the idle / stall issue is before being overly concerned about the routing of the vacuum lines to the wiper and washer bottle, etc. That is certainly relatively complicated and includes properly routing the lines into the car under dash. The only vacuum line you need be concerned with initially is that line travelling between the inlet manifold and the back side of the vacuum pump (bottom section of double action fuel/vacuum pump). The line coming from the front side of the vacuum pump can be blocked off for now - hopefully that is the line going to your wiper motor. It would be helpful if you had more photos but I can see from the top photo that the larger diameter hose seems correctly routed to the wiper motor but then the smaller diameter hose that breaks away from the Y Junction should not also be feeding into the wiper motor. There is a good routing diagram in the workshop manual from memory. That diagram also available at the Hometown Buick website. Further, a search on this site should find it possibly searching under 'wiper vacuum routing' or similar. But I would if possible just block off that line going to the wiper motor for now and concentrate on the idle/stall issue.

I looked at the spark coming from the coil again and that didn't look that hot and energetic. We will see what happens with another coil.

Not having much luck in locating the gremlin. Next step will be to use a friend's coil to see if that makes a difference. But that won't be until next weekend.

Voltage check of primary circuit of coil when engine running shows 12.6 volts. The plug wires all have resistance between 12000 and 18000 ohms. In the dark I can see no flashing at spark plug boots to suggest spark leakage to the engine block. I can't see any cracks or damage to the distributor cap. I suppose that despite the coil being in spec there still could be an output problem...what colour should the spark be coming from the coil lead...I assume blue-white rather than red-orange?

Alas, I am going to have to keep looking. So far, the coil measures resistance to spec but I will look at all the other aspects.

I believe you are all correct in that the resistance of the carbon rod in the rotor is for protection against interference. I think the carbon rod in mine has been fried or something else. I also removed it and attempted to clean it up with sandpaper and that just made it worse with the resistance now some 70,000 ohms. I suspect the initial 11,000 ohms reading was not as it should be either but I can't be sure without measuring a replacement. Anyway, thanks to all for the considered thoughts and information. New rotor on the way.

Having a quick look at part listings on the Net, the rotor with the rod is described as a resistor coil. It is listed as applicable to all early-mid 50s GM cars. Still no idea why you need the resistance as it will only serve to cause a voltage drop. Maybe there was a need to reduce the current, I don't know.

I still ponder why that carbon rod is being used in the rotor at all rather than just a strip of metal. Willie, I hazard a guess the engine backfired given that the rod had become slightly displaced. This displaced rod was interrupting the voltage flow, which was exaggerated at higher rpms with resulting irregular spark at the plugs. And eventually the rod popped out altogether with that gap then causing the voltage to arc or jump from the centre of the rotor and that large arc or spark melting the rotor. The carbon rod is certainly not used with many rotors. However, certainly I see rotors being used for Buick and Cadillac in the mid 50s do use this setup. I an not sure what other manufacturers were using.

Googling some more on the Internet it appears that carbon rod in the rotor is supposed to have resistance but not sure how much. Wish I had a spare sitting around to do a check. Anyway I have no idea why Buick/GM would want to have resistance across the rotor. I did see some write ups where people had ditched that carbon rod and epoxied in a nail cut to length or similar.