The Stovebolt Site Forums The Shop Area Engine Shop 261 oil lines.

Prepping my 261 for life again and have a question. The oil line holes in the block are quite small, 1/4" or so (guessing as I'm away from the shop), but I know I have another oil canister setup from a different 261 that runs 3/4 lines. Is it possible to use the 3/4 filter setup on the small line holes in this block? Will the pressure difference adversely affect it in any way?
Thanks.

What year 261 engine do you have?

1954-1957 261 engines were set up for by-pass oil filters (and have a smaller line, as used in all 235 and 216 engines).

The 1958-63 261s could be set three ways:
- no oil filter
- by-pass oil filter (smaller diameter lines)
- full-flow oil filter (1/2 NPT lines - the 3/4" lines you refer to).

The full-flow oil filter should only be used on a full-flow 261 block/engine.

It looks like your engine uses a by-pass oil filter. Do not try to use/adapt smaller lines with that full-flow 261 oil canister with large lines/ports.

Thanks Tim. It is a 62 261. But it did not come with an oil canister. It was removed. Will an oil canister off a 216 work on this? I have a couple parts trucks that have 216's with oil canisters on them.

Fox,

Yes - but, if you can, post a photo of where the hoses goes into the block (just to be sure about hoses/filters).

Fox, ditto everything Tom said. Here is a link to Deve's 261 website that explains this subject well.

http://devestechnet.com/Home/TheVenerable261

The oil flow 'dowel' (described in Deve's above article) sounds like it is positioned 'out' for bypass. It can be pushed 'in' if you want full flow.

I'll probably get some rocks thrown at me for the idea below, but here goes...

There is another option if you go full flow. You can easily plumb the system with both a full flow spin-on filter and your 216 canister bypass filter. All oil goes through the full flow filtered circuit all of the time, then a small percentage of the oil leaves the full flow filter and heads to the bypass filter before it gets returned to the crankcase.

Why? To quote Hotrod Lincoln, the spin-on filter "catches rocks and marbles" while the bypass filter removes the smaller particles. The filters have different size screens. The dual filter system should give your engine cleaner oil all of the time than either single filter system.

Your 216 bypass filter works for dual filter design because of the 1/16" restrictor orifice inside the canister.

Overkill? Maybe. But, hey, it's a hobby. Either single filter system will work fine and has been proven through the years. But the 261 is configured to easily combine the two to get the best of both.

I'm building a 261 and have plumbed it for the dual filters with Hotrod Lincoln's help. It is still in the build stage, so I can't provide any operating testimonial. Be happy to provide pictures of the set up if anyone is interested.

Matt

Matt,

I have a 235 that I've driven personally over 100k miles w/o a filter, I just change the oil every season (4x/year).

That said I have a '62 model 261 in the wings and I have pushed the dowel IN.

I am very interested in your combination full/bypass filtering and would appreciate pictures. I've been thinking of adding a Frantz tp filter as the bypass.

Here are pictures. I took them from different angles. The first ones don't have labels, the second ones do. I thought it might be easier to be able to match the labeled pictures to the unlabeled ones.

http://s844.photobucket.com/user/ma...2106_zpsvxikh3hh.jpg.html?sort=2&o=0

I used brass NPT fittings and copper tubing. I used hard lines because everything is attached to the block. 1/2" tubing is used for full flow and 1/4" tubing is used for bypass.

One thing might confuse folks. The feed line (the one for the oil pressure gauge tee) for a bypass engine become the return for a full flow. Pushing in the dowel changes the oil route. The feed line for the full flow is the 1/2" NPT fitting under the dowel.

The 1/8" NPT bung just to the left of the full flow feed (normally plugged for full flow) is the return for the bypass when using dual filters. It dumps directly into the crankcase.

The full flow return line has a tee that feeds the bypass filter. The bypass filter MUST have a 1/16" reducer orifice.

My bypass filter will be mounted on the manifold with one of the brackets that was available for the AD trucks that centers the canister on the manifolds instead of having it front or back.

Why did I use Fram decals on an AC canister? Because I had the decals. Why is the engine yellow? 261's were painted yellow (one year only) in 1957. The 261 came from a 1957 cement truck and will go into my 1957 3600. How can a '57 261 have a full flow dowel? The 261 had a 1964 replacement block. How can it be a 1964 block if production for 261's ended in 1962? GM made replacement blocks until 1964.

Matt

What is your:

1. Engine Serial Number
2. Head casting code
3. Head casting date
4. Block casting code
5. Block casting date

Here are locations for those codes.

Engine blocks and heads were cast after the 261 was last standard equipment/option in 1963.

When you say 1/2" tubing was used, were both the "full flow" fittings into the block 1/2" NPT?

Tim, the block doesn't have a serial number which is consistent with some replacement blocks. It had an 850 head which I gave away because I will be using an 848 head with the six steam holes added. I forget the block casting date, but it decoded as January, 1964.

Yes, the full flow fittings are 1/2" NPT. The engine had been set up for bypass. The 1/2" bypass feed (oil gauge) had a 1/2"NPT to 1/8"NPT reducer bushing.

The original color of everything on the engine (except for the block) was yellow underneath several layers of Chevy orange. I think the old cement truck had a tough life. The layers of paint indicated several rebuilds and even the non-original block had been bored .060 over and was worn enough that I had to have it bored .080 over.

Matt

Matt, that hard line looks like it's going to be really close to your exhaust, are you sure it's going to clear?

Cosmo, that's a great question.

It should be OK based on the measurements that I took off the 235 that is currently in my truck. The reason that the return line for the full flow (the one with the oil gauge tee) has the nipple installed to make it longer is for the exhaust clearance.

That side of the engine will be more crowded than stock. My A/C compressor is mounted high and my alternator is mounted low (reverse of most installations). Fortunately, these are on my existing 235 so I could get very accurate measurements. The spin-on filter will tuck behind the alternator and will be easy to get to from underneath. I'm mounting the bypass canister with the centering bracket off an AD series to push it toward the fender a bit to get it out of the way and to give me easy access to the spin-on filter.

I'll be installing a split manifold that I put together using the dump off a scrap 235 exhaust manifold welded toward the rear of a stock one. I used the stock 235 exhaust manifold in my truck to measure for clearance around everything for the front dump and taped on a mock-up to make clearance provisions for the rear dump.

Here is a picture of the split manifold.

http://s844.photobucket.com/user/ma...2042_zps2ufxktpq.jpg.html?sort=3&o=0

My plan is not only to make sure everything fits, but to also leave accessibility to have plenty of room to work on everything.

Fingers crossed that it all fits in as planned!

Matt

You might be OK relative to Cosmo's justified concern, Matt

The original "full-flow filter housing's plumbing" had thin metal tubing "standoffs" to clear the single exhaust pipes? I have used similar "stand offs" to clear dual exhaust Fenton manifolds/exhaust-pipes.

Tim, thanks. I've seen that picture before but never noticed the stand offs. Thanks for pointing them out.

Matt

So as I understand it, I have a 62 261 that is most likely in bypass mode. (I still need to check). Therefore, I drive the dowel in for full flow. Does switching to full flow allow the following...or is Tim still correct?
Because the line holes in the block are the "little guys", I assume I still can't use the "big line" oil filter assembly?

I don't believe any Canadian 261 was set up for full flow oil filter, if that happens to be what you have.

I looked closely at my block last night and it seems that there isn't a dowel there. What the? It is a 261 by the casting code, no dowel on the driver side, but there are two dowelish things on the passenger side by the distributor hole. Please educate me some more fellas.
My guess, as stated above, is that it is a 62 261 locked into bypass mode by means of not having the dowel to switch.

The engine is a 62
3769717
The head came with it and is a 848.
The lines in the block are the little guys.
The filter I wanted to use had the big lines (full flow).

But I think I will go with the bypass system for now as it will be easiest to do at this point.

Those are actually two smooth-headed bolts that hold the oil pump bracket to the block.

DO NOT REMOVE OR LOOSEN THEM!

That oil pump bracket is aligned at the factory with a special fixture, and if it gets out of alignment it can cause the distributor shaft to run in a bind and break the shaft or wear out the drive gear and/or the camshaft gear.

Can you post a link to a photo of the driver's side of your block? If so, maybe someone who is familiar with 261's can confirm whether of not there's a dowel.
Jerry

Well Fox, my 1961 Pontiac 261 came with 848 head and bypass oil filter also. I don't know if truck engines had full flow or not.

All the late (58-62) Canadian 261 blocks I have seen have the casting boss for the diverter pin but it is not machined see here. Personally I would never modify for a full flow filter... just not worth the effort as a high performance bypass will do a better job IMO. Amsoil's website has detailed information for dual filter setups if one feels that is the answer.

Curt, some great info on the Amsoil site...thanks for sharing.
_______
AMSOIL Ea Bypass Oil Filters provide maximum filtration protection against wear and oil degradation. Working in conjunction with the engine's full-flow oil filter, AMSOIL Ea Bypass Filters operate by filtering oil on a "partial-flow" basis.

They draw approximately 10 percent of the oil sump's capacity at any one time and trap the extremely small, wear-causing contaminants that full-flow filters can’t remove. AMSOIL Ea Bypass Filters typically filter all of the oil in the system several times an hour, so the engine continuously receives analytically clean oil.
________

I think that we can conclude that all configurations...no filter, bypass or full flow... have all proven to be effective in these engines. Simply a matter of personal preference. I'll err toward more filtration, but that is a personal choice.

Fox, if you need a bypass canister for your installation because your full flow won't work, drop me a PM. I think I have an extra one or two laying around.

Matt

My block is like the photo Curt posted.

OK- - - -bypass filtering only, then. I'd suggest going with one of the ultra-fine mesh filter systems similar to Frantz or Amsoil so the oil that goes through the filter gets a thorough cleanup. That's probably a better situation than doing a mediocre job of filtering oil that has to flow fast enough to keep the bearings lubed.
Jerry

Sounds good!

I'm working on an idea to convert a standard-appearing Fram or AC filter canister to accept the Frantz-style toilet paper roll instead of an original-equipment filter cartridge. Those filters strain out much finer particles than the regular filter element.
Jerry

Resurrecting an old post just to show a picture of the final plumbing of the dual full flow and bypass filters on the 261 that I'm almost done with.

Per HRL's recommendation, I decided to use a Frantz toilet paper filter for the bypass instead of the AC canister. I got lucky and found one in the scrap pile of a salvage yard. I mounted it on the rear of the intake manifold to leave more room for my AC compressor which is mounted high on the same side. The plug in the gauge hole is temporary.

Everything fit fine even with the dual exhaust manifold.

http://s844.photobucket.com/user/ma...359_zpsbjeoqwg4.jpg.html?sort=2&o=10

Matt

Looks real nice, Matt

Nice dual exhaust manifold, too.

Was your 261 originally yellow, or did you prefer to use that 261 yellow color? It looks good.

That's a lot of filtration! Nice. I've heard all kinds of crazy stories about the Frantz filters extending oil change times.

Tim, it was originally yellow. The engine came from a '57 6400 cement truck. Everything but the block had the original yellow paint under several layers of Chevy orange. The block was replaced at some point in its life. It has a 1964 build date and no serial number. From the research I did, '57 was the one year the 261's were painted yellow. Since it started life yellow in a '57, and since it is going into a '57, I painted it yellow.

Thanks for the comment about the manifold. I got the ideal from this site--

http://www.restorodstogo.com/2011/01/235-261-chevrolet-split-dual-exhaust.html

HRL helped me with advice on welding cast iron and how to split the cylinder banks by milling a slot through the back side, then fitting and welding in a plug.

Matt

On the big rigs with the Frantz elements for the LuberFiner 750 filter housings, we were changing filters at 10K mile intervals, and never changing the crankcase oil. Some engines had 80K or more on the oil, and it was still passing a spectrometric sample test. Of course, the crankcase capacity was 10 gallons, and we added 1 1/2 gallons to top off after the filter change.
Jerry

Matt, thanks for posting those pics- I'm going to be starting on the plumbing for my 261 very soon and this is exactly how I want to do it... The PO of my truck had rebuilt the motor only 10k ago, but when I tore it down it had evidence of oil starvation at the rocker shafts and at the cam bearings. It's a full flow motor but someone had plumbed the filter with tiny bypass lines. I'm going to make sure it's done right this time.

How in the world did you replicate that exhaust manifold? It is beautiful...I don't understand how the second outlet was fabricated- can you elaborate?

Thanks, Dave.

What kind of vehicle is the 261 going in? I'm pretty sure in my AD truck that the Frantz in the rear position would have some issues with steering column

The engine is going into my '57 3600.

The manifold is made from two manifolds, a good one and a donor. It's a shadetree mechanic's way to replicate the '53-'54 Corvette manifold. The good manifold has a 1/4" slot cut into the back ahead of the #4 cylinder. A plug is carved with a die grinder to fit inside the slot to block off the front cylinder bank from the back bank. The plug is welded into place when the slot is welded shut.

The exhaust dump off the donor manifold is cut off using an angle grinder. The heat flapper box is cut off at an angle. Fabricate a piece and weld it to the exhaust dump where the heat flapper box was cut at an angle. The exhaust dump is then is carefully ground and shaped to fit over the 4-5-6 cylinder end of the manifold about where the part number is cast. Once the dump fits correctly, the outline is traced on to the good manifold. Move the lines in 1/4" and cut out the shape. Bevel the edges of the exhaust dump to accept weld, then weld into position.

All of the fabricated parts are made from metal from the donor manifold This avoids mixing metals which can create welding complications and expansion/contraction issues during operation.

Welding cast can be tricky to prevent cracking and warping. I used a #6 rosebud torch to preheat. I mig welded with Crown Alloys Royal 44-30 .35 wire which is a nickel manganese blend designed for cast iron. I welded in short stitches of about 1" and used the pointed end of a slag hammer to relax the weld after each stitch with about a minute of steady, firm tapping. The first pass was for penetration. Additional passes were made to fill. Once finished, the weld was buried in sand overnight to cool slowly. It was ground down after it cooled off.

Here are a few more pix including a couple that I pulled off eBay about a year ago showing the front and back of the Corvette manifold. Note that the Corvette manifold is cast so that they cylinder banks are separated.

http://s844.photobucket.com/user/ma...2040_zpsghebo01x.jpg.html?sort=3&o=2

I bolted the intake and exhaust manifolds together and had the machine shop mill the flanges perfectly flat while they were joined together to get a good seal just in case there was any warping caused by the welding. That cost $35, but it was well worth it.

I went with this design to get the benefit of the split exhaust and still retain the factory heat exchanger system.

Matt

Matt's 261 with Frantz filter
1960 standard location of full-flow filter

I do not think that the Frantz filter is located closer to the firewall than the original full-flow oil filter is located?

Once again, that is a beautiful set-up, Matt
Please post a picture when/if you get it in place in your truck.

Thanks Matt. [EDIT] Okay, I see now how you did the manifold.. that is a lot of additional welding compared to doing a simple split- I am amazed that you were able to keep the manifold from cracking. Great work.

I currently have a split manifold, but the added rear flange has only a 1 1/2" ID and I am having trouble believing that it will be worth putting in the truck with such a small diameter outlet. It looks like it was made from one of those exhaust splitting kits that they used have back in the day.

I'm actually in complete agreement. It looks really sharp. I was just trying to picture it in my truck (an AD). I don't think firewall is an issue, but steering column and/or fender brace might be. I'm not as familiar with the clearance issues in a task force or 60s truck.

Without extensive modification by block (a 235) wouldn't have the full flow piece of that system anyway. Speaking of which, will the Frantz work with the "standard" bypass plumbing of a 216/235? As in, would it get the appropriate amount of flow?

The Frantz will flow oil somewhat more slowly than a regular bypass filter due to the much more dense filtering media. No problem, as a bypass filter doesn't have to flow enough oil to keep the engine lubricated- - - -it just strains out contaminants, period. Early Frantz filters didn't have a proprietary housing- - - -they were conversions of standard Fram and AC housings. I'm working on making a set of adapter plates to use rolls of cheap toilet paper in a regular Fram-type housing. All it takes is a couple of 1/4" aluminum plates machined to accept an O ring seal to direct the oil flow through the roll of paper.
Jerry

Is there a "spec" on the type of TP that needs to be used? Seems like I read somewhere that it takes a different diameter of cardboard tube than is common today.

That's the purpose of the aluminum plates top and bottom- - - -they seal the ends of the roll and force the oil to soak through the sides. A spacer can be fabricated to accommodate any center tube size desired. I'll probably use a piece of aluminum conduit with a bunch of holes drilled in it as a centering sleeve. I think I'm going to use John Wayne style CHEAP paper (80 rolls/$56.00 with free shipping)- - - -I don't really care what bears do in the woods with the expensive stuff!
Jerry

From what I have read, the filters worked best with the old Scottissue single ply 1000 count toilet paper. It used to be sold in single rolls and was advertised as septic tank friendly. It is still sold, but in multipacks and the rolls are 4" wide instead of 4.5" wide.

The filters supposedly work best with single ply instead of double ply because of the layers of filtration. And adding quilting might be better on you bottom, but is detrimental to filtering.

The cheap, single ply rolls found in public restrooms are supposed to work very good in the filters, but I had trouble finding any without having to buy it by the jumbo case from a restaurant supply company.

I bought some 1000 count single ply in a 4 pack at Walmart over the weekend for about $2.50. It is about 4.25" wide. It fit into the canister very well...nice and tight, packed it in with the bottom of a one pound coffee can, core stayed round and did not lose its shape, exactly how I wanted it...super snug.

OK, enough about my toilet paper research!

Ed Greany now owns the Frantz company that was started by John Frantz. His website is--

www.toiletpaperoilfilter.com

Ed sells a newer version called "The Refiner", but he also carries the parts for the vintage one like I have. Great guy to work with. He sells the gaskets for the old ones. Not listed on his website, but he also has the decals for the old ones. The one in my picture has one of his replacement decals on it.

Matt