Oil Cooler Info for 48 C-170

Jim Brann · Post by **Jim Brann** » Thu Dec 01, 2005 2:15 am

Hello, can anyone tell me how to go about intalling an oil cooler in a 1948 C-170 that I just put on floats? I need to know if there is an STC and what the part numbers are for the cooler and oil screen adaptor. Thanks Jim jabdjb@quixnet.net

Post by **GAHorn** » Thu Dec 01, 2005 2:56 am

You've got a ragwing on floats?

mit · Post by **mit** » Thu Dec 01, 2005 6:42 am

OH my god

Post by **GAHorn** » Thu Dec 01, 2005 7:06 am

There was a very small oil cooler available on the C-125 which involved an adaptor between the screen and the accy case, and to which bolted the small cooler. It was not approved for the C-145. There was also a Cessna Service Kit which applied to the 172 seaplane, but it's rare to find, and virtually impossible to locate a complete kit. (Although I did see one offered NOS about 3 years ago in an ad.) This might lead us to a salvage yard search, but when I return home from this trip, I'll look thru my references and see if I can find some more info on it.
Some Swift's have an oil cooler plumbed to the front oil galleries, but that requires the engine to be split to install a restrictor in the front of the case. It also had little effect according to one owner I talked to who had it on his Swift (an aircraft inspector and former RAM aircraft engines technician.)

I presume you're aware of the 240 -degree redline on our engines when used with SAE 50 wt oil? (See the engine type certificate Note 1.)

NOTE 1. Maximum permissible cylinder head, barrel and oil inlet temperatures, 525Â°F, 290Â°F, and 225Â°F, respectively.
Maximum oil inlet temperature limit is 240Â°F, when using Spec. MHS-24 oil SAE No. 50 above 40Â°F ambient and SAE No. 30 or 10W30 below 40Â°F ambient.

N2865C · Post by **N2865C** » Thu Dec 01, 2005 3:23 pm

You might also want to check your oil temp. gauge. The former owner of my plane spent a lot of time and money trying to get the oil temps down. I discovered that the gauge was reading about 30 degrees high, apparently not an uncommon way for the gauges to fail. I now spend my time trying to figure out how to get my oil temps up on cool days.

Jim Brann · Post by **Jim Brann** » Sat Dec 03, 2005 3:23 am

gahorn wrote:There was a very small oil cooler available on the C-125 which involved an adaptor between the screen and the accy case, and to which bolted the small cooler. It was not approved for the C-145. There was also a Cessna Service Kit which applied to the 172 seaplane, but it's rare to find, and virtually impossible to locate a complete kit. (Although I did see one offered NOS about 3 years ago in an ad.) This might lead us to a salvage yard search, but when I return home from this trip, I'll look thru my references and see if I can find some more info on it.
Some Swift's have an oil cooler plumbed to the front oil galleries, but that requires the engine to be split to install a restrictor in the front of the case. It also had little effect according to one owner I talked to who had it on his Swift (an aircraft inspector and former RAM aircraft engines technician.)

I presume you're aware of the 240 -degree redline on our engines when used with SAE 50 wt oil? (See the engine type certificate Note 1.)

NOTE 1. Maximum permissible cylinder head, barrel and oil inlet temperatures, 525Â°F, 290Â°F, and 225Â°F, respectively.
Maximum oil inlet temperature limit is 240Â°F, when using Spec. MHS-24 oil SAE No. 50 above 40Â°F ambient and SAE No. 30 or 10W30 below 40Â°F ambient.

Thanks for the Info George, I was not aware of the temp limits, and a matter of fact, without looking at my gage, I can't even remember if the scale was F or C I'm pretty sure my cylinder head temp gage is in centigrade, but I'm not sure about the oil temp gage. I do think it is original 1948 vintage though. Thanks again, Jim

zero.one.victor · Post by **zero.one.victor** » Sat Dec 03, 2005 7:13 am

I don't have it here, but if you look in the C-145 IPC there is an oil cooler set-up shown. I believe that it uses an adapter and/or fittings at the oil screen, kinda like Geoge describes, but I think the cooler was plumbed to a remote location. I think a guy I know with a C-145 powered Swift has that cooler set-up. You might check the swifter website(s) for info.
Interesting that you have a 48 model on floats, The TCDS is pretty specific that the floats listed as item 209 (Edo 89-2000) are approved only for the A or B model. What model floats are you running?

Eric

Post by **GAHorn** » Wed Dec 07, 2005 10:31 am

That's the one to which I was referring, Eric. It is not remotely located tho'. It's mounted directly to the adaptor and to my knowlege it's not applicable to the C-145/O-300. It's also not very effective and requires a dedicated blast tube.

cessna170bdriver · Post by **cessna170bdriver** » Wed Dec 07, 2005 3:43 pm

gahorn wrote:That's the one to which I was referring, Eric. It is not remotely located tho'. It's mounted directly to the adaptor and to my knowlege it's not applicable to the C-145/O-300. It's also not very effective and requires a dedicated blast tube.

I'm still compiling my list of parts for overhaul, so I have the Illustrated Parts List with me. There are two separate assemblies shown in "Figure 12 Oil Cooler Equipment". Items 1 -10 are parts for an oil cooler, one of which is an adapter that appears to require hoses for connections. The adapter also contains a bypass valve. There does not appear to be any means to attach directly to the engine. Nor is there a bracket that would allow for attachment anywhere else, for that matter. This assembly is listed as being applicable only to the C-125-2 engine (Code A).

Items 11 - 24 are part of an assembly called "Adapter Equipment, Oil Cooler", that appear to install in place of the pressure screen in the accessory cover. The adapter has a built-in oil pressure relief valve, as well as provisions for external hose connections and an oil screen similar to the original (but different part #). This assembly is listed as being applicable only to the C-145-2 (Code B).

It would appear that the two assemblies COULD be connected by hoses, but if that were the case, why the different application codes?

Miles

Jim Brann · Post by **Jim Brann** » Sun Dec 18, 2005 3:04 am

zero.one.victor wrote:I don't have it here, but if you look in the C-145 IPC there is an oil cooler set-up shown. I believe that it uses an adapter and/or fittings at the oil screen, kinda like Geoge describes, but I think the cooler was plumbed to a remote location. I think a guy I know with a C-145 powered Swift has that cooler set-up. You might check the swifter website(s) for info.
Interesting that you have a 48 model on floats, The TCDS is pretty specific that the floats listed as item 209 (Edo 89-2000) are approved only for the A or B model. What model floats are you running?

Eric

Hi Eric, I got my CD from the FAA today, I checked the 337 form dated 5/26/54 and it says the my straight 170 is approved and accepted for 89-2000 floats to Cessna drg. 0541125 my plane is 4138V and the other rag-wing that had CAA approval was N-3991V I don't know why the TCDS does not list the striaght 170 as well? Let me know what you think, Jim

zero.one.victor · Post by **zero.one.victor** » Mon Dec 19, 2005 6:03 am

Jim, on that 337, how is the installation approved? Who signed off the "Approval for return to service" in Box 6?
The way I understand it, an IA can sign off a change that is approved by TCDS, or a change approved by STC-- but a CAA rep had to sign off anything else, which would be a so-called field approval. Not sure just what a CRS can sign off on.
BTW, the "approval for return to service" on a modern form 337 is box 7. The current version of form 337 has been used since 11-88. The form 337 which should have been filed in 1954 was used starting 4-52. There you go, a fascinating bit of aviation trivia-- no extra charge.

Eric

Jim Brann · Post by **Jim Brann** » Tue Dec 20, 2005 1:52 am

Hi Eric, I'm not sure how it is approved? The form I am looking at from "52 " must be differant than what you are talking about now. The box I am looking at is under box 7 and says "To be completed by CAA representatives" There is a signature of the designee who is clearly Francis L. Gauthier and then under it, signature of inspector who is a F.W. Fala???? the handwriting is like a doctor's. but it was submitted on 5/24/54 the designee signed it 5/26/54 and the inspector signed it on 6/2/54. I did notice that the upper left hand corner on the form I am looking at says "Form ACA-337" Then under it in () it says (11-7-45) in very fine print. Hope this helps, Jim

zero.one.victor · Post by **zero.one.victor** » Tue Dec 20, 2005 5:56 am

Not that it matters at this late date, but I think they used an out-of-date 337. I have a 337 that sounds like the one you describe, it was filled out in 1952. The date under "Form ACAS-337" in the top LH corner is (11-48 ).
The next 337 in my file was filled out in 1955, the bottom RH corner sez Form ACA-337 (4-52).
The earlier form doesn't have the wording "approved for return to service" anywhere. The lowest box has 2 checkoff boxes, one sez approved and one sez rejected.
I see your 337 cites Cessna dwg 0541125. The TCDS approves the edo's using that install dwg for the 170A, the 170B is approved using dwg 0541125B. Float approval for the ragwing is clearly missing from the TCDS. I would say that yours would be considerd a field approval. Don't matter though- approved is approved!
How do you know that the other ragwing 3991V is also approved? Is it also listed on your 337?

Eric

Jim Brann · Post by **Jim Brann** » Tue Dec 20, 2005 10:18 pm

Hello again Eric, Yes the other installation is listed on the 337 form. It was done by Ron Twitchell in Turner Maine. He was killed in a 170 accident in 1970. My plane has a modified flight manual done by copying Ron's flight manual for N3991V. It says in a note in box 7, "Installation simular to Cessna N3991V approved District (1) July 22, 1950. So that's two rag-wings that I know of that had approved float installation. By the way, I got off the water this past summer with myself 230, my son 220, and a friend I estimate at least 220 and full fuel tanks. And I am running a C-145! (I did have 100 avgas though, not auto fuel like I run in the winter.) This float flying is new to me, but I am well pleased with the performance of my old airship. I hope I had mentioned that the wings on my plane were metalized in June of 1956. Best regards, Jim

mit · Post by **mit** » Wed Dec 21, 2005 6:47 am

Jim Brann wrote:Hello again Eric, Yes the other installation is listed on the 337 form. It was done by Ron Twitchell in Turner Maine. He was killed in a 170 accident in 1970. My plane has a modified flight manual done by copying Ron's flight manual for N3991V. It says in a note in box 7, "Installation simular to Cessna N3991V approved District (1) July 22, 1950. So that's two rag-wings that I know of that had approved float installation. By the way, I got off the water this past summer with myself 230, my son 220, and a friend I estimate at least 220 and full fuel tanks. And I am running a C-145! (I did have 100 avgas though, not auto fuel like I run in the winter.) This float flying is new to me, but I am well pleased with the performance of my old airship. I hope I had mentioned that the wings on my plane were metalized in June of 1956. Best regards, Jim

I had a copy of a 337 field approval for a 48. Now I can't find it. I had a 48 for 10 years and was going to do it, but never got around to it. Now I have a B on floats with a 145. If you got off the water with that load in your plane. Your a better pilot than me! Do you have the exta tank in the left wing?