Just got this 56 Olds about a month ago. Can't get the vacuum wipers to work so I decided to use an early Chevy electric motor that I understand fits perfectly. My question is what to do with the lines coming from the fuel pump? I would think that blocking the line to the wiper motor would be fine since it's normally closed anyway. The line to the carb base is what concerns me. I disconnected it, and although it's normally connected to vacuum it seems to be puffing. I don't want to screw up my fuel pump so I'm reluctant to block it off. Any advice?

 

I have a 57 tri power so I may be of no help, where there are 2 ports on top of the fuel/vacuum pump. One goes to the vacuum wiper and the other goes to the center carb base. There is another port on the center carb that goes to the vacuum brake booster check valve. Does your line just go right into the carb base and nowhere else? Why not buy a threaded plug to block off the one going to the vacuum wiper and leave the other one going to the carb?

I had a similar dilemma and ended up sending my vacuum motor to be rebuilt. It was ~$100 and works really well.


Good luck.

 

You should be able to just cap the line to the base of the carb and remove the line off the vacuum unit if you're switching to electric. The top portion of the fuel pump is a vacuum pump; it has a second diaphragm other than the fuel pump diaphragm, they're both hooked up to the same rod, but if the vacuum side isn't being used, just leave it open. As long as it isn't going to the carb, otherwise you'll have to cap the line headed to the wiper motor. It's just supposed to equalize vacuum so that the wipers don't either stall or take off when either accelerating or backing off the gas. It never worked excessively well. In fact, the car will develop a miss if there's a hole in that diaphragm that will be difficult to source,and it may consume oil as a result. So it bodes well to convert to electric wipers. All of the vacuum systems I've ever used never worked worth a tinker's cuss.

 

The early chevy wiper motor you speak of is not a direct bolt on. It can be made to work but the holes are not a direct match up .Been there done that. I believe I tried to use a 57 Chevy optional electrical wiper motor if memory is correct. But the easy way is to use the Newport Engineering unit . You might try a search on Newport wiper sometime in the past I had a thread on this conversion that will point out a few things that will save you a bunch of time and grief. I can't seem to find it tonight.

You won't be disappointed with this unit it's well made and reliable. About the extra vacuum lines just plug them off with a close fitting bolt. I hide them so it looks as though they still go too their appropriate places just for the judges to ponder...... Tedd

Found it! Man how time flies it was back in 2012.....https://classicoldsmobile.com/forums...oday-55-a.html

 

I followed Tedd's advise a few years ago and the conversion to Newport was relatively quick and flawless. I also plugged off the vacuum lines.

 

X3 on the Newport. It cost a little more but for the ease of installation and the reliability it is a bargain. You can put your original **** on the switch so it looks original.

 

Since the fuel pump is pulling vacuum, I wondered if plugging the hole from the carb wouldn't affect the diaphragm?

 

Not really, the wiper motor is technically deadheaded too. Besides, it's a different diaphragm that runs the vacuum. So if it develops a leak, ( a lot of them did) worst case is it just sucks in crankcase oil. What some people have done is just disconnect that diaphragm from the shaft and cut the stem so it doesn't come into contact with the diaphragm and click or just removed it entirely and put in a gasket to keep the oil out.

 

Thanks to Tedd's post I also went with the Newport.( Hard to believe it was seven years ago) Going by his directions a very easy install. Very happy with it and the bat wing air cleaner still fits.
Rick