Lyc Intake pipe O ring issue

[cajunwings]

Opinions please: This is a new one for me. Installing a forward sump IO-360 on an 7 after a fresh Overhaul. Took a couple of intake pipes off to facilitate installing other things. When reinstalling these intake pipes the big red O ring ends up very deep inside the sump bore. The #2 intake pipe is almost impossible to install without the O ring going into the sump. It’s like the pipes are at least 1/4” too long or the O ring carrier/holder part is in the wrong spot. The machined bore in the sump where the O ring lives is a bit over 1” long. One would think this is to accommodate intake pipes of slightly different lengths and the O ring would live near the middle of this bore, but in this case it’s right on the inside edge. I sent this engine in and assume I got the same pipes back. Have calls into the shop and have not heard back yet.

Don Broussard
RV9 Rebuild in Progress (Painting now)
57 Pacer

 

[Full Throttle]

Opinions please: This is a new one for me. Installing a forward sump IO-360 on an 7 after a fresh Overhaul. Took a couple of intake pipes off to facilitate installing other things. When reinstalling these intake pipes the big red O ring ends up very deep inside the sump bore. The #2 intake pipe is almost impossible to install without the O ring going into the sump. It’s like the pipes are at least 1/4” too long or the O ring carrier/holder part is in the wrong spot. The machined bore in the sump where the O ring lives is a bit over 1” long. One would think this is to accommodate intake pipes of slightly different lengths and the O ring would live near the middle of this bore, but in this case it’s right on the inside edge. I sent this engine in and assume I got the same pipes back. Have calls into the shop and have not heard back yet.

Don Broussard
RV9 Rebuild in Progress (Painting now)
57 Pacer

Did you happen to notice if the tubes fit properly before you pulled them out. If not, there the Wrong intake tubes for that front facing sump. Check with the people that overhauled the engine. Maybe that's a Angle Valve engine 200 hp. sump. Angle valve cylinders are longer. Those tubes won't work with a parallel valve cylinder and Angle Valve sump.

 

[cajunwings]

Did you happen to notice if the tubes fit properly before you pulled them out. If not, there the Wrong intake tubes for that front facing sump. Check with the people that overhauled the engine. Maybe that's an Angle Valve engine 200 hp. sump. Angle valve cylinders are longer. Those tubes won't work with a PP valve cylinder and AV sump.

I didn’t need to remove the intake tubes before shipping the engine out for O/H so can’t say how they fit. If I got the same tubes back they have been flying on this engine/aircraft for 600 hrs. The same cylinders were reinstalled so that part of the height equation is unchanged. The crankcase was replaced and the oil sump and accy case and other pieces went to Divco for O/H. Maybe something is slightly different in the stackup? I would like these pipes to be 3/8 to 1/2” shorter, that would place the O ring in the middle of the bore. What is a AV sump? Thanks.

Don B

 

[Mikeyb]

Here’s a pic of an IO-360 M1B. It seems different. The bores seem shallower on mine. The O-rings do sit very close to the inside edge. I had to use a hose clamp to keep the tube/O-ring from going in too far and destroying the O-ring

 

[Ironflight]

I’d be checking part numbers (they are usually stamped on the intake tubes if genuine Lycoming - but you may have to blast the paint off to see them) against the parts catalog. I have played games with intake tubes and sumps before - had to go through a few sets to get it right on one engine. I was really surprised a week or so back when we changed all the top end seals on our IO-540 that all six tubes had the same part number and were interchangeable- some engineer at Lycoming clearly screwed up with this mechanic-friendly design, and I am guessing he was reprimanded for it….

 

[Full Throttle]

I didn’t need to remove the intake tubes before shipping the engine out for O/H so can’t say how they fit. If I got the same tubes back they have been flying on this engine/aircraft for 600 hrs. The same cylinders were reinstalled so that part of the height equation is unchanged. The crankcase was replaced and the oil sump and accy case and other pieces went to Divco for O/H. Maybe something is slightly different in the stackup? I would like these pipes to be 3/8 to 1/2” shorter, that would place the O ring in the middle of the bore. What is a AV sump? Thanks.

Don B

PV is for Paralell Valve

I didn’t need to remove the intake tubes before shipping the engine out for O/H so can’t say how they fit. If I got the same tubes back they have been flying on this engine/aircraft for 600 hrs. The same cylinders were reinstalled so that part of the height equation is unchanged. The crankcase was replaced and the oil sump and accy case and other pieces went to Divco for O/H. Maybe something is slightly different in the stackup? I would like these pipes to be 3/8 to 1/2” shorter, that would place the O ring in the middle of the bore. What is a AV sump? Thanks.

Don B

Sorry...AV Angle Valve engine.

 

[chaskuss]

Did you happen to notice if the tubes fit properly before you pulled them out. If not, there the Wrong intake tubes for that front facing sump. Check with the people that overhauled the engine. Maybe that's a Angle Valve engine 200 hp. sump. Angle valve cylinders are longer. Those tubes won't work with a parallel valve cylinder and Angle Valve sump.

The IO-360-M1B [parallel valve] engines use the same part number [LW-13864] sump as the following other models. Only the intake tubes differ.

IO-360-A1D, IO-360-J1A6, IO-360-J1A6D, HIO-360-D1A, AEIO-360-A1E & AEIO-360-A1E6

Edit Also IO-360-A3B6

 

[cajunwings]

The IO-360-M1B [parallel valve] engines use the same part number [LW-13864] sump as the following other models. Only the intake tubes differ.

IO-360-A1D, IO-360-J1A6, IO-360-J1A6D, HIO-360-D1A, AEIO-360-A1E & AEIO-360-A1E6

This is a parallel valve IO-360. The data plate says B1E, that and the intake pipes being too long are the only things I can be certain of. I suspect this may be a mix and match Lyc. The easiest way to solve this problem may be to move the O ring holder 3/8” up the pipe. It appears to be silver soldered in place.

 

[chaskuss]

This is a parallel valve IO-360. The data plate says B1E, that and the intake pipes being too long are the only things I can be certain of. I suspect this may be a mix and match Lyc. The easiest way to solve this problem may be to move the O ring holder 3/8” up the pipe. It appears to be silver soldered in place.

Your IO-360=B1E originally came with sump P/N 78778, which is a bit of an oddball. It is a horizontal, rear facing servo sump and is not a "tuned induction" sump, as used on the IO-360-M1B and the angle valve IO-360-Axx variants. FYI, the angle valve 360 sumps will physically bolt up to the parallel valve 320, 340 & 360 crankcases. So odds are someone used one of the other angle valve "tuned intake" sumps to convert your engine to a forward facing setup. It is mostly likely a P/N 74384. Repositioning the O-ring sleeves will probably be your easiest cure. What exhaust system are you using? I ask, because I've been told [no firsthand experience] that if the angle valve IO-360-Axx variant intake tubes are used, you will have clearance issues with the "Vetterman 4 into 2" exhaust system meant for the IO-360-M1B. It is possible to use the angle valve intake tubes, but a 3/8" thick spacer must be fabricated to fit between the intake tubes and the exhaust port of each cylinder. This will also require replacement of the exhaust port studs with longer units. I "think" I have a photo of this setup somewhere on 1 of my many hard drives.

 

[chaskuss]

Your IO-360=B1E originally came with sump P/N 78778, which is a bit of an oddball. It is a horizontal, rear facing servo sump and is not a "tuned induction" sump, as used on the IO-360-M1B and the angle valve IO-360-Axx variants. FYI, the angle valve 360 sumps will physically bolt up to the parallel valve 320, 340 & 360 crankcases. So odds are someone used one of the other angle valve "tuned intake" sumps to convert your engine to a forward facing setup. It is mostly likely a P/N 74384. Repositioning the O-ring sleeves will probably be your easiest cure. What exhaust system are you using? I ask, because I've been told [no firsthand experience] that if the angle valve IO-360-Axx variant intake tubes are used, you will have clearance issues with the "Vetterman 4 into 2" exhaust system. It is possible to use the angle valve intake tubes, but a 3/8" thick spacer must be fabricated to fit between the intake tubes and the exhaust port of each cylinder. This will also require replacement of the exhaust port studs with longer units. I "think" I have a photo of this setup somewhere on 1 of my many hard drives.

Don,
I found the photos of the spacers mentioned above. I also have extracted the 3 pages of the Parts Catalog concerning the various IO-360 sumps with drawings of what they look like. If interested, PM me with your email address and I'll send them to youl