Looking for oil cooler
Thu Jul 23, 2009 11:53 pm
made by UAP part no. U-3170-W-D5 for BT-13. The one I have on the plane will not let the throttle push rod clear the valve housing. In the photos you can see how close the push rod travels near the outlet fitting.
Mark D
Mark D
Fri Jul 24, 2009 12:00 am
Can't the oil cooler body be rotated out of the way in the frame? It looks like the cooler has an outer frame/support with upper & lower pieces clamped together with the side bolts, so it should be simple enough to loosen the side bolts, and work the outlet a little to the side- Or am I mistaken about the construction?
Robbie
(also an A&P)
Robbie
(also an A&P)
Fri Jul 24, 2009 1:24 am
Can you put a longer bolt with a spacer through the bolt to further offset the rod?
Fri Jul 24, 2009 1:57 am
Can't the oil cooler body be rotated out of the way in the frame? It looks like the cooler has an outer frame/support with upper & lower pieces clamped together with the side bolts, so it should be simple enough to loosen the side bolts, and work the outlet a little to the side- Or am I mistaken about the construction?
Robbie
(also an A&P)
I think you're mistaken. The inlet to the oil cooler has a eccentric shape, so if it were rotated the eccentric shape wouldn't line up with the flange.
Fri Jul 24, 2009 9:33 am
A2C wrote:Can't the oil cooler body be rotated out of the way in the frame? It looks like the cooler has an outer frame/support with upper & lower pieces clamped together with the side bolts, so it should be simple enough to loosen the side bolts, and work the outlet a little to the side- Or am I mistaken about the construction?
Robbie
(also an A&P)
I think you're mistaken. The inlet to the oil cooler has a eccentric shape, so if it were rotated the eccentric shape wouldn't line up with the flange.
I meant rotate the whole oil cooler a tad to one side- shouldn't take much... It is round, and in a round frame...And the lines are connected by hoses, so there is a bit of flexibility. Should only need about 1" or so of clearance.
Another thought might be to recheck the throttle linkage- perhaps the original was replaced? Maybe there had been a different one originally- one with an offset to pass around the oil cooler fitting- like a dogleg?
Robbie
Fri Jul 24, 2009 10:39 am
I think I agree with Robbie. You shouldn't need much rotation from the cooler to give plenty of clearance to the push rod, depending on the flexibility of the hose/aluminum tube piping.
Otherwise, I have done offset linkages (doglegged) on many occasions with much success. The only downside is setting length sometimes because of the rotation of the now "bent" rod using left and right hand rod ends. We used to lock one end and then just adjust the other independantly until the slip of the bolt through the rod end and the attach point was correct. But you guys all have those skill sets.
(not an A&P, just old race car mechanic)
Otherwise, I have done offset linkages (doglegged) on many occasions with much success. The only downside is setting length sometimes because of the rotation of the now "bent" rod using left and right hand rod ends. We used to lock one end and then just adjust the other independantly until the slip of the bolt through the rod end and the attach point was correct. But you guys all have those skill sets.
(not an A&P, just old race car mechanic)
Fri Jul 24, 2009 2:10 pm
The inlet has an eccentric shape, and it's a casting connected to the threaded rods. If you rotate the rods, you rotate the casting below the oil cooler. The inlet air box will then not line up with the eccentric shape at the bottom of the oil cooler.
Fri Jul 24, 2009 3:59 pm
Gotcha now. So the dog leg in the connecting rod could still be an option depending on the clearance required as the link swings through an arc at the attach point. 
Fri Jul 24, 2009 4:58 pm
A2C wrote:The inlet has an eccentric shape, and it's a casting connected to the threaded rods. If you rotate the rods, you rotate the casting below the oil cooler. The inlet air box will then not line up with the eccentric shape at the bottom of the oil cooler.
Losen the clamps on each end of the cooler, and rotate the circular cooler in the frame, not everything connected to the cooler. Leave the tie rods alone. This way you won't have to mis align the lower air deflector.
Sat Jul 25, 2009 6:55 pm
Mark,
Is the arm on the carb correct?
I know there are different lengths so a shorter arm will move the linkage up.
There are some with more of a offset or bend as well.
Also is it clocked with serrations? If so playing with a start point can help.
Rich
Is the arm on the carb correct?
I know there are different lengths so a shorter arm will move the linkage up.
There are some with more of a offset or bend as well.
Also is it clocked with serrations? If so playing with a start point can help.
Rich
Sat Jul 25, 2009 9:17 pm
Mark, I have pictures of an old bt project that hasn't flown in 30 years. I cant guarantee that it is the original engine but it has a spacer on the bolt at the throttle arm. I will email it if I had your address.
Tue Jul 28, 2009 10:08 pm
Hi Guys
We are in Osh right now and I have looked at 1 BT and the cooler is in the right position in the mount. The housing that I have on ours is for sure a larger one that I found on the one here. I think this is where the problem is.
Rich - good point about the throttle arm. I can check the one here again. I didn't take notice earlier.
Mark D
We are in Osh right now and I have looked at 1 BT and the cooler is in the right position in the mount. The housing that I have on ours is for sure a larger one that I found on the one here. I think this is where the problem is.
Rich - good point about the throttle arm. I can check the one here again. I didn't take notice earlier.
Mark D
Wed Jul 29, 2009 1:46 pm
If you deciede the cooler or valve is the problem, for me there is only one choice, Pacific Oil Coolers. Last time I used them I needed a oil cooler for a A-26, and they had one on the shelf, and I had it the next day.