On the right side of my 1957 Cadillac engine low and to the rear of the block there is a fitting and a steel line that runs to the top rear of the engine. Please advise as to it's function. Regards, Ron
Exactly where on the "top rear" of the engine does this line run to? Cylinder head, back of block, intake manifold?
Vacuum line from trans to intake????? Kind of hard to tell you what it actually is with your description. Post some pics and we will let you know.
Low and to the rear of block is not the intake manifold. The oil filter lines attach to the front area of the block. The steel line terminates exactly at the top of the rear of the engine. Please no more guessing. Appreciate a knowledgeable answer. Regards, Ron
"No more guessing"? Well, guess I won't be able to assist then... I just happen to have a Cad in my roadster, so I'm somewhat familiar with them. Some Cads had a vacuum boost pump on the bottom of the oil pump that was plumbed to a fitting and line "low and to the rear of the block" . But I didn't say that as it would just be a guess... Jeeez
A picture is worth a thousand words. OK here is my guess...the line coming off the exhaust manifold to control the carburator choke.
Yup, what warbird said. It was to assist the vacuum wipers. Buicks and others used a double action fuel pump for vacuum assist but Caddy wanted something more complex and harder to work on I belive it was only used from '56-'58...but don't hold me to it.
Warbird said what I was gonna say. if you ever pull the pan you,ll see it they fail due to the casing wearing on the vacuum drive...
"Please no more guessing. Appreciate a knowledgeable answer." <!-- / message --><!-- sig -->haha.. dude wtf ?? You post a crappy description of a line that could be one of a few things, no picture, no other info and expect someone to tell you exactly what it is ?? OK.. how about this.. theres a bolt on the right side of my motor, low that screws in to the block. Please dont guess I want a knowledgeable answer. Thanks.,,
Hey, thanks, I knew it wouldn't be a difficult question or description for someone versed in this vintage Cadillac. As you are Cadillac knowledgeable, please advise, can I replace the oil pump with attached vacuum pump with an earlier or later oil pump without the extraneous vacuum pump? Regards, Ron
I disconnected the vacuum part of my oil pump in my 57 engine, with no problems down the road. You can use your oil pump without it hooked up. And while you have it out, SBC high pressure oil pump springs interchange with the later (56-62?) Cad oil pumps. -Torr
I'm not Cadillac knowledgeable really, you just caught me at the right time. My dad has a '58 Caddy and he just so happened to have his oil pump/vacuum pump torn all apart on the shop table less than a week ago. The motor was rebuilt and after running for a few hours a squeal developed, sounded like a dry bearing. Checked the bearings and they looked perfect, tore the oil pump/vacuum pump apart and the bottom of the vacuum pump was scarred up like it had been dragging. Since he has converted to electric wipers he decided to get rid of the vacuum pump portion. From what I remember of it there's a plate between the oil pump and vacuum pump, there was a hole/opening in it that he welded shut and left the vacuum pump off (it's still on the table acutally). If you want me to ask him exactly what was done and how it all works let me know, he spent the better part of a day studying the manual and pump diagram.
As '58 was the last year of vacuum wipers for Cadillac was the oil pump sans vacuum pump in '59? Is it a direct replacement for the earlier oil pump? Appreciate the information. Regards, Ron
I asked my dad yesterday about the pump, he confirmed that there's a steel plate between the oil pump and vacuum pump. He welded up the few small openings in the steel plate and left the vacuum pump off, it's working just fine. As far as the pump interchange, I'm not sure but somebody with a GM parts interchange book should be able to tell you quite easily. In '59 they did change to the 390ci. So obviously the bore/stroke are different. As far as the rest of the motor internals, I'm not 100% sure.