The Stovebolt Site Forums The Shop Area Engine Shop Bypass oil filter connections

Hi All,

I searched this but came up with a goose egg, so here goes. I'm working on a '51 GMC with the 228 engine. I've pulled a bunch of the front end off in order to replace the radiator support and I was looking at the plumbing for the cannister oil filter. On this engine it's bolted to the passenger side of the engine at the front. The line that feeds to the side of the housing comes from the front of the engine. On my truck, this line has a piece of rubber line (fuel line? vacuum line?) that joins the two pieces of steel line that are attached at the front of the engine and at the filter.

This is a very original truck - 25,000 miles - radiator cap, fan belt and all hoses and clamps are original. My question is what type of rubber line is the short (about 4-5") piece of hose? On the GMC engine you've got a 60lb. pressure system. What's on there now is one of the few things that isn't original - looks like a piece of vacuum line held on by two small hose clamps. That seems like a recipe for disaster to me. I don't have flaring tools or I'd replace the 2 piece line with its rubber connector with a single run of line. Any suggestions?

Thanks,

David Bush

I would think a hydraulic repair shop or a truck repair shop (Catepillar dealer) should be able to make you one...

How are all of your trucks set up? Do you also have a short piece of flex hose joining the two steel tubing ends? I'm curious as to how it was originally set up leaving the factory.

I have an original one that looks it was all one piece from the factory. A steel line comes out of the T Block and over the timing cover. Then it looks like a flex line is factory crimped to the line. There is about 6" of flex line that ends in an EL fitting with a flare to go to the filter housing. When these lines were still available from GMC, I never remember replacing one because they never broke. I looked at a couple of my old GMC's and they seem to all have some kind of jerry rigged flex except for the one that I know to be original. I know there is a restricter in the line somewhere. I think it is at the end of the flex line which would put full pressure on the flex line. I'm not sure if anyone makes reproduction lines. I'm sure a NOS would be just as rotten as what I have one mine. Our Cummins Diesels use a stainless steel line for oil to the turbo. I think it could be adapted to work. It's not a fun thing to work on because the line is crammed in behind the filter and the lower radiator hose.