The Stovebolt Site Forums The Shop Area Engine Shop spin-on filter for '60 261

Does anyone have any advice on installing a spin-on oil filter on a 1960 261 engine?
The lines to the stock oil filter are 3/4 inch.

Thanks, Tim

I've done this on my 261. FYI, The block fittings are for 1/2"NPT pipe. I used a "remote filter adapter kit". Jegs, Summit, etc... sell these kits for about $35 I think, comes with an aluminum spin-on plate assembly that can be mounted to the firewall, etc.... and a pair of hoses with fittings. They come in 2 styles, one with the hoses coming in from the top, the other with them from the sides.

:confused: Does the 261 have the same oil patterns as the 235's in other words do they filter 10 percent of the oil through the filter? Thanks Mick Inniss

Mick - The 261 oil galley is set up for a full flow filter, not a bypass like the 235 was.

261's 58 and newer have a full flow filter option.On my two 261's, a 59 and a 62, one has a filter kit mentioned above and the other uses the stock full flow filter which mounts on the intake and has the same filter cannister as the early Chevy V-8's. The earlier engines use a bypass like a 235.

Thank's guy's for the info!!! I will be looking for a 261 in the near future!!! I hope it will be a 58 or newer now!! like the idea of the full pressure system. Thanks again Mick Inniss

gearhead and others,

Thanks for the information. I have found that this site is frequented by people who have great knowledge, and they have great experience and sometimes wisdom, and the people on this site have refined senses of humor.

My 1960 is a full-flow oil system.

In case you are interested, gearhead refers to these companies:
http://www.jegs.com/ http://www.summitracing.com/

By the way, the holes in my block are 7/8" (NP-14 threads - or close to it). I also checked the male/female ends of the hoses with a tap and die. I assume I can use adapters to 1/2" NPT or to the other other threads on the various relocation adapters (3/4-16 and 13/16-16, for example). Does anyone have any comments on this (for example, does a reduction adapter block anything in the oil journals in the block)? I vaguely recall that the full-flow systems have some sort of valve at or near the hole for the line to the oil filter. If by any chance the line/filter gets plugged, the bypass diverts the oil-flow back through the block - does this sound familiar to anyone (I do not have an engine manual for the full-flow 261)?

I also assume that I could connect the oil pressure sender to a tee fitting on the "in" hose or to a threaded hole that is shown on the top of a few of the relocation adapters. Any comments on this?

Thanks, Tim

Mick - If you go to the tech tips page, there is an article on converting a 235 or early 261 to full pressure oiling. It's not that difficult if the engine is apart.

Please use -10 or larger hose!
Since you are going to this trouble you might consider a 'System one' oil filter also then you can clean it and never buy another filter
again

Tim: The by-pass/check valve is mounted in the stock cannister mount (top). In the aluminium block there is a fibre washer and spring. If your filter gets plugged it will by-pass there. If you do not use the stock by-pass mount set-up, and you have a line restriction, the pump will by-pass at the pressure regulator located in the oil pump. (The oil pump is a displacement pump, and may take out the cover gasket if the oil has no where to go.) There is a simple solution to this, just change your oil. (REGULARLY). Just kiddin, I know you will. You have got the one of the good years of 261's. In 59' the oil pump pick-up was improved and has a baffle installed to prevent pressure loss and pump cavitation from surges and sudden stops. Also in 59' and up you have full pressure oiling to the rocker shaft and arms because of the increase in size of the passages from the cam bearings. Also new on 59' and up 261's was a new style of thermostat/housing and water pump, said to be improved over earlier designs. After 4 years of use GM finally had most all the bugs out of the 261. I have two 261's, a 59' and a 61' and really like this engine. They both have the factory oil filter.

Both my 261's have 1/2 inch npt oil ports , which measure about 7/8 of an inch.There is also a dowel recessed into the block near one of the oil ports.In theory this dowel is set in one of two positions. One position allows normal oil flow out the port to the filter and back. In the other position is an internal bypass to allow engine operation without a filter .

Tony, what position is the dowel pin in. Mine is flush with the outside of the block,I was told it needed to be pushed in to use the filter.I have 40/45 lbs. of oil pressure like it is but would like to have a filter. Just a little nervous about trying to knock the pin in.

I am in need of one of these mentioned by-pass valves for my 283. Might anyone happen to have a spare they would be willing to part with?
Bruce

I am in the process of reinstalling the oil filter assembly that came off of my 216. I am putting the dual offy manifold on a 235 engine and I hope that the oil filter's original attachment works there. Has anybody done this? Also, it appears that this is an AC (dealer add-on) filter unit. What color blue is the bottom? I beleive that the top is Chevy Orange. I am inclined to use engine paint for the heat. I agree that this filter may only be marginally effective, but I will relish the excuse to change the oil often.

The pin should be "out" (flush) for full flow.

Pipe is not measured by the outside diameter, that's why its larger than 1/2". Take a caliper with you to the hardware store next time. You can get a chart that tells what the OD and wall thicknesses are for future reference if you want.
Tubing is measured by OD.

Yes the pin just above the lower oil port.On the 261 in my 51, the pin is flush. On the 261 in my 37 ,the Pin is in about 1/2 an inch.Interesting.I knew nothing about the pin position 6 years ago when I built the 37 engine.The 51 has the correct cannister filter. I know its filtering.I checked the pin position when I assembled the engine. Last time I changed the oil,the filter can seal was installed wrong. Oil went everywhere when the engine started. On the 37 truck with an aftermarket adapter that uses a screw on filter,I can squeeze the hoses when the engine is off, but once running I can't squeeze the hose, can feel the oil flowing through.Don't remember about the pin when I put the engine together.The oil filter is hot after the engine is warmed up.Whatever, no worries.

The pin has to be IN to fully filter the oil. The pin blocks the oil coming in from the oil pump. The oil must then flow out the 1/2" NPT port, through the filter, and back to the engine via the other 1/2" NPT port (rear). If the pin is out, any filtering will be bypass only, just like the 235. In Phat's article about converting a 235 to full filtering oil, he installs a plug in the galley coming from the oil pump. The pin in the IN position does the same thing as the pipe plug.

If the pin is in the IN position, YOU MUST RUN AN OIL FILTER!!!!

Yup Racecarl, the pin is in for filter use.When the 261 block in my 51 was sitting on the engine stand, I closely checked the pin and the oil ports.I remember looking in the hole that the tubing feed from the oil pump goes into . I could see the dowel blocking the passage, forcing the oil through the port and through the oil filter.But the pin is flush on the outside.This one is different for some reason.

OK, so now I'm corn-fused, my '60 261 has the pin flush to the outside, and 30psi at 650rpm fully warmed up. Not sure if the passage is blocked or not anymore. Seams to me that if the by-pass operates like the 235 does, then I wouldn't have any pressure with the 1/2" lines, as I tried this on a 235 back when I didn't know any better and only had 5psi when warm. With that assumption in mind, its either got an extra long pin like Tonys has, or the passage should be open for full flow??? Tony, what year is the block you have with the longer pin? Also, does anybody have a 58-62 repair manual handy that might shed some light on this area? I'm thinking maybe they made a slight change to this setup on the latter ones??

The 261 is a 1962 engine.I don't know if the pin is longer, but knew about the pin position , so I checked it out when this engine was rebuilt.The hoses and filter will show system pressure whether the pin is out or in.Back fed from the oil galley.